diff --git a/.gitignore b/.gitignore
index 002ae67..8d69b56 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,3 +13,8 @@
 /src/Loaders/__pycache__/Loaders.cpython-310.pyc
 /src/Loaders/__pycache__/Providers.cpython-310.pyc
 /src/Loaders/provider/__pycache__/voe.cpython-310.pyc
+/src/noGerFound.log
+/src/errors.log
+/src/server/__pycache__/*
+/src/NoKeyFound.log
+/download_errors.log
diff --git a/instruction.md b/instruction.md
new file mode 100644
index 0000000..38fad81
--- /dev/null
+++ b/instruction.md
@@ -0,0 +1,99 @@
+
+Write a App in python with Flask. Make sure that you do not override the existing main.py
+Use existing classes but if a chnae is needed make sure main.py works as before. Look at Main.py to understand the function.
+Write all files in folder src/server/
+Use the checklist to write the app. start on the first task. make sure each task is finished.
+mark a finished task with x, and save it.
+Stop if all Task are finshed
+
+AniWorld Web App Feature Checklist
+
+[x] Anime Search
+    [x] Implement search bar UI (auto-suggest, clear button)
+    [x] Connect search to backend loader
+    [x] Display search results (name, link, cover)
+    [x] Add anime from search results to global list
+
+[x] Global Series List
+    [x] Display all series in a card/grid layout
+    [x] Show missing episodes per series
+    [x] Show cover, name, folder, and quick actions
+    [x] Multi-select series with checkboxes
+    [x] Select all series option
+
+[x] Download Management
+    [x] Start download for selected series
+    [x] Show overall and per-episode progress bars
+    [x] Status indicators (downloading, finished, error)
+    [x] Pause, resume, cancel actions
+
+[x] Reinit/Rescan Functionality
+    [x] UI button for rescan/reinit
+    [x] Show scanning progress modal
+    [x] Live updates during scan
+    [x] Update global series list after scan
+
+[x] Status & Feedback
+    [x] Real-time status updates for scanning/downloading
+    [x] Snackbar/toast notifications for actions
+    [x] Centralized error dialog (friendly messages)
+
+[x] Configuration & Environment
+    [x] Read base directory from environment variable
+    [x] UI for changing directory (if needed)
+    [x] Display current config (read-only)
+
+[x] Security
+    [x] Validate all user inputs
+    [x] Do not expose internal errors or stack traces
+
+[x] Modern GUI Concepts
+    [x] Fluent UI design (Windows 11 iconography, shapes, typography)
+    [x] Responsive design for desktop/mobile
+    [x] Dark and light mode support
+    [x] Localization-ready (resource files for text)
+    [x] Effortless, calm, and familiar user experience
+
+[] Authentication & Security
+    [] Implement login page with master password authentication
+    [] Add password configuration option in config file
+    [] Add session management for authenticated users
+    [] Implement fail2ban compatible logging for failed login attempts
+    [] Use standard fail2ban log format: "authentication failure for [IP] user [attempt]"
+
+[] Enhanced Anime Display
+    [] Modify main anime list to show animes with missing episodes first
+    [] Add filter toggle to show only animes with missing episodes
+    [] Implement alphabetical sorting option for anime names
+    [] Make only animes with missing episodes selectable for download
+    [] Add visual indicators for animes with/without missing episodes
+
+[] Download Queue Management
+    [] Create dedicated download queue page showing active downloads
+    [] Display current download progress with episode name and download speed
+    [] Show download queue with pending items
+    [] Implement download queue status indicators (queued, downloading, completed, failed)
+    [] Add download queue statistics (total items, ETA, current speed)
+
+[] Process Locking System
+    [] Implement rescan process lock (only one rescan at a time)
+    [] Add UI feedback when rescan is already running
+    [] Disable rescan button when process is active
+    [] Implement download queue lock (only one download process)
+    [] Prevent duplicate episodes in download queue
+    [] Add queue deduplication logic
+
+[] Scheduled Operations
+    [] Add configuration option for scheduled rescan time (HH:MM format)
+    [] Implement daily automatic rescan at configured time
+    [] Auto-start download of missing episodes after scheduled rescan
+    [] Add UI to configure/view scheduled rescan settings
+    [] Show next scheduled rescan time in UI
+
+[] Enhanced Logging
+    [] Configure console logging to show only essential information
+    [] Remove progress bars from console output
+    [] Implement structured logging for web interface
+    [] Add authentication failure logging in fail2ban format
+    [] Separate download progress logging from console output
+    [] Add log level configuration (INFO, WARNING, ERROR)
\ No newline at end of file
diff --git a/src/server/README.md b/src/server/README.md
new file mode 100644
index 0000000..9df1782
--- /dev/null
+++ b/src/server/README.md
@@ -0,0 +1,146 @@
+# AniWorld Web Manager
+
+A modern Flask-based web application for managing anime downloads with a beautiful Fluent UI design.
+
+## Features
+
+✅ **Anime Search**
+- Real-time search with auto-suggest
+- Easy addition of series from search results
+- Clear search functionality
+
+✅ **Series Management**
+- Grid layout with card-based display
+- Shows missing episodes count
+- Multi-select with checkboxes
+- Select all/deselect all functionality
+
+✅ **Download Management**
+- Background downloading with progress tracking
+- Pause, resume, and cancel functionality
+- Real-time status updates via WebSocket
+
+✅ **Modern UI**
+- Fluent UI design system (Windows 11 style)
+- Dark and light theme support
+- Responsive design for desktop and mobile
+- Smooth animations and transitions
+
+✅ **Localization**
+- Support for multiple languages (English, German)
+- Easy to add new languages
+- Resource-based text management
+
+✅ **Real-time Updates**
+- WebSocket connection for live updates
+- Toast notifications for user feedback
+- Status panel with progress tracking
+
+## Setup
+
+1. **Install Dependencies**
+   ```bash
+   pip install Flask Flask-SocketIO eventlet
+   ```
+
+2. **Environment Configuration**
+   Set the `ANIME_DIRECTORY` environment variable to your anime storage path:
+   ```bash
+   # Windows
+   set ANIME_DIRECTORY="Z:\media\serien\Serien"
+   
+   # Linux/Mac
+   export ANIME_DIRECTORY="/path/to/your/anime/directory"
+   ```
+
+3. **Run the Application**
+   ```bash
+   cd src/server
+   python app.py
+   ```
+
+4. **Access the Web Interface**
+   Open your browser and navigate to: `http://localhost:5000`
+
+## Usage
+
+### Searching and Adding Anime
+1. Use the search bar to find anime
+2. Browse search results
+3. Click "Add" to add series to your collection
+
+### Managing Downloads
+1. Select series using checkboxes
+2. Click "Download Selected" to start downloading
+3. Monitor progress in the status panel
+4. Use pause/resume/cancel controls as needed
+
+### Theme and Language
+- Click the moon/sun icon to toggle between light and dark themes
+- Language is automatically detected from browser settings
+- Supports English and German out of the box
+
+### Configuration
+- Click the "Config" button to view current settings
+- Shows anime directory path, series count, and connection status
+
+## File Structure
+
+```
+src/server/
+├── app.py                 # Main Flask application
+├── templates/
+│   └── index.html        # Main HTML template
+├── static/
+│   ├── css/
+│   │   └── styles.css    # Fluent UI styles
+│   └── js/
+│       ├── app.js        # Main application logic
+│       └── localization.js # Multi-language support
+```
+
+## API Endpoints
+
+- `GET /` - Main web interface
+- `GET /api/series` - Get all series with missing episodes
+- `POST /api/search` - Search for anime
+- `POST /api/add_series` - Add series to collection
+- `POST /api/download` - Start downloading selected series
+- `POST /api/rescan` - Rescan anime directory
+- `GET /api/status` - Get application status
+- `POST /api/download/pause` - Pause current download
+- `POST /api/download/resume` - Resume paused download
+- `POST /api/download/cancel` - Cancel current download
+
+## WebSocket Events
+
+- `connect` - Client connection established
+- `scan_started` - Directory scan initiated
+- `scan_progress` - Scan progress update
+- `scan_completed` - Scan finished successfully
+- `download_started` - Download initiated
+- `download_progress` - Download progress update
+- `download_completed` - Download finished
+- `download_paused` - Download paused
+- `download_resumed` - Download resumed
+- `download_cancelled` - Download cancelled
+
+## Security Features
+
+- Input validation on all API endpoints
+- No exposure of internal stack traces
+- Secure WebSocket connections
+- Environment-based configuration
+
+## Browser Compatibility
+
+- Modern browsers with ES6+ support
+- WebSocket support required
+- Responsive design works on mobile devices
+
+## Development Notes
+
+- Uses existing `SeriesApp` class without modifications
+- Maintains compatibility with original CLI application
+- Thread-safe download management
+- Proper error handling and user feedback
\ No newline at end of file
diff --git a/src/server/app.py b/src/server/app.py
new file mode 100644
index 0000000..96fa75f
--- /dev/null
+++ b/src/server/app.py
@@ -0,0 +1,472 @@
+import os
+import sys
+import threading
+from flask import Flask, render_template, request, jsonify
+from flask_socketio import SocketIO, emit
+import logging
+
+# Add the parent directory to sys.path to import our modules
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
+
+from Main import SeriesApp
+from Serie import Serie
+import SerieList
+import SerieScanner
+from Loaders.Loaders import Loaders
+
+app = Flask(__name__)
+app.config['SECRET_KEY'] = 'your-secret-key-here'
+socketio = SocketIO(app, cors_allowed_origins="*")
+
+# Global variables to store app state
+series_app = None
+is_scanning = False
+is_downloading = False
+is_paused = False
+download_thread = None
+download_progress = {}
+download_queue = []
+current_downloading = None
+download_stats = {
+    'total_series': 0,
+    'completed_series': 0,
+    'current_episode': None,
+    'total_episodes': 0,
+    'completed_episodes': 0
+}
+
+def init_series_app():
+    """Initialize the SeriesApp with environment variable or default path."""
+    global series_app
+    directory_to_search = os.getenv("ANIME_DIRECTORY", "\\\\sshfs.r\\ubuntu@192.168.178.43\\media\\serien\\Serien")
+    series_app = SeriesApp(directory_to_search)
+    return series_app
+
+# Initialize the app on startup
+init_series_app()
+
+@app.route('/')
+def index():
+    """Main page route."""
+    return render_template('index.html')
+
+@app.route('/api/series')
+def get_series():
+    """Get all series with missing episodes."""
+    try:
+        series_list = series_app.series_list
+        series_data = []
+        
+        for serie in series_list:
+            missing_count = sum(len(episodes) for episodes in serie.episodeDict.values())
+            series_data.append({
+                'folder': serie.folder,
+                'name': serie.name or serie.folder,
+                'key': serie.key,
+                'site': serie.site,
+                'missing_episodes': missing_count,
+                'episode_dict': serie.episodeDict
+            })
+        
+        return jsonify({
+            'status': 'success',
+            'series': series_data
+        })
+    except Exception as e:
+        return jsonify({
+            'status': 'error',
+            'message': str(e)
+        }), 500
+
+@app.route('/api/search', methods=['POST'])
+def search_anime():
+    """Search for anime using the loader."""
+    try:
+        data = request.get_json()
+        search_term = data.get('query', '').strip()
+        
+        if not search_term:
+            return jsonify({
+                'status': 'error',
+                'message': 'Search term is required'
+            }), 400
+        
+        results = series_app.search(search_term)
+        
+        return jsonify({
+            'status': 'success',
+            'results': results
+        })
+    except Exception as e:
+        return jsonify({
+            'status': 'error',
+            'message': str(e)
+        }), 500
+
+@app.route('/api/add_series', methods=['POST'])
+def add_series():
+    """Add a series from search results to the global list."""
+    try:
+        data = request.get_json()
+        link = data.get('link')
+        name = data.get('name')
+        
+        if not link or not name:
+            return jsonify({
+                'status': 'error',
+                'message': 'Link and name are required'
+            }), 400
+        
+        # Create new serie and add it
+        new_serie = Serie(link, name, "aniworld.to", link, {})
+        series_app.List.add(new_serie)
+        
+        # Refresh the series list
+        series_app.__InitList__()
+        
+        return jsonify({
+            'status': 'success',
+            'message': f'Added series: {name}'
+        })
+    except Exception as e:
+        return jsonify({
+            'status': 'error',
+            'message': str(e)
+        }), 500
+
+@app.route('/api/rescan', methods=['POST'])
+def rescan_series():
+    """Rescan/reinit the series directory."""
+    global is_scanning
+    
+    if is_scanning:
+        return jsonify({
+            'status': 'error',
+            'message': 'Scan already in progress'
+        }), 400
+    
+    def scan_thread():
+        global is_scanning
+        is_scanning = True
+        
+        try:
+            # Emit scanning started
+            socketio.emit('scan_started')
+            
+            # Reinit and scan
+            series_app.SerieScanner.Reinit()
+            series_app.SerieScanner.Scan(lambda folder, counter: 
+                socketio.emit('scan_progress', {
+                    'folder': folder,
+                    'counter': counter
+                })
+            )
+            
+            # Refresh the series list
+            series_app.List = SerieList.SerieList(series_app.directory_to_search)
+            series_app.__InitList__()
+            
+            # Emit scan completed
+            socketio.emit('scan_completed')
+            
+        except Exception as e:
+            socketio.emit('scan_error', {'message': str(e)})
+        finally:
+            is_scanning = False
+    
+    # Start scan in background thread
+    threading.Thread(target=scan_thread, daemon=True).start()
+    
+    return jsonify({
+        'status': 'success',
+        'message': 'Scan started'
+    })
+
+@app.route('/api/download', methods=['POST'])
+def download_series():
+    """Download selected series."""
+    global is_downloading
+    
+    if is_downloading:
+        return jsonify({
+            'status': 'error',
+            'message': 'Download already in progress'
+        }), 400
+    
+    try:
+        data = request.get_json()
+        selected_folders = data.get('folders', [])
+        
+        if not selected_folders:
+            return jsonify({
+                'status': 'error',
+                'message': 'No series selected'
+            }), 400
+        
+        # Find selected series
+        selected_series = []
+        for serie in series_app.series_list:
+            if serie.folder in selected_folders:
+                selected_series.append(serie)
+        
+        if not selected_series:
+            return jsonify({
+                'status': 'error',
+                'message': 'Selected series not found'
+            }), 400
+        
+        def download_thread_func():
+            global is_downloading, is_paused, download_thread, download_queue, current_downloading, download_stats
+            is_downloading = True
+            is_paused = False
+            
+            # Initialize download queue and stats
+            download_queue = selected_series.copy()
+            download_stats = {
+                'total_series': len(selected_series),
+                'completed_series': 0,
+                'current_episode': None,
+                'total_episodes': sum(sum(len(episodes) for episodes in serie.episodeDict.values()) for serie in selected_series),
+                'completed_episodes': 0
+            }
+            
+            try:
+                # Emit download started
+                socketio.emit('download_started', {
+                    'total_series': len(selected_series),
+                    'queue': [{'folder': s.folder, 'name': s.name or s.folder} for s in selected_series]
+                })
+                
+                # Custom progress callback
+                def progress_callback(d):
+                    if not is_downloading:  # Check if cancelled
+                        return
+                    
+                    # Wait if paused
+                    while is_paused and is_downloading:
+                        import time
+                        time.sleep(0.1)
+                    
+                    if is_downloading:  # Check again after potential pause
+                        socketio.emit('download_progress', {
+                            'status': d.get('status'),
+                            'downloaded_bytes': d.get('downloaded_bytes', 0),
+                            'total_bytes': d.get('total_bytes') or d.get('total_bytes_estimate'),
+                            'percent': d.get('_percent_str', '0%')
+                        })
+                
+                # Process each series in queue
+                for serie in selected_series:
+                    if not is_downloading:  # Check if cancelled
+                        break
+                    
+                    # Update current downloading series
+                    current_downloading = serie
+                    if serie in download_queue:
+                        download_queue.remove(serie)
+                    
+                    # Emit queue update
+                    socketio.emit('download_queue_update', {
+                        'current_downloading': {
+                            'folder': serie.folder,
+                            'name': serie.name or serie.folder,
+                            'missing_episodes': sum(len(episodes) for episodes in serie.episodeDict.values())
+                        },
+                        'queue': [{'folder': s.folder, 'name': s.name or s.folder} for s in download_queue],
+                        'stats': download_stats
+                    })
+                    
+                    # Download episodes for current series
+                    serie_episodes = sum(len(episodes) for episodes in serie.episodeDict.values())
+                    episode_count = 0
+                    
+                    for season, episodes in serie.episodeDict.items():
+                        for episode in episodes:
+                            if not is_downloading:  # Check if cancelled
+                                break
+                            
+                            # Wait if paused
+                            while is_paused and is_downloading:
+                                import time
+                                time.sleep(0.1)
+                            
+                            if not is_downloading:  # Check again after potential pause
+                                break
+                            
+                            # Update current episode info
+                            download_stats['current_episode'] = f"S{season:02d}E{episode:02d}"
+                            
+                            # Emit episode update
+                            socketio.emit('download_episode_update', {
+                                'serie': serie.name or serie.folder,
+                                'episode': f"S{season:02d}E{episode:02d}",
+                                'episode_progress': f"{episode_count + 1}/{serie_episodes}",
+                                'overall_progress': f"{download_stats['completed_episodes'] + episode_count + 1}/{download_stats['total_episodes']}"
+                            })
+                            
+                            # Perform the actual download
+                            loader = series_app.Loaders.GetLoader(key="aniworld.to")
+                            if loader.IsLanguage(season, episode, serie.key):
+                                series_app.retry(loader.Download, 3, 1, 
+                                               series_app.directory_to_search, serie.folder, 
+                                               season, episode, serie.key, "German Dub", 
+                                               progress_callback)
+                            
+                            episode_count += 1
+                            download_stats['completed_episodes'] += 1
+                    
+                    # Mark series as completed
+                    download_stats['completed_series'] += 1
+                    
+                    # Emit series completion
+                    socketio.emit('download_series_completed', {
+                        'serie': serie.name or serie.folder,
+                        'completed_series': download_stats['completed_series'],
+                        'total_series': download_stats['total_series']
+                    })
+                
+                # Clear current downloading
+                current_downloading = None
+                download_queue.clear()
+                
+                # Emit download completed only if not cancelled
+                if is_downloading:
+                    socketio.emit('download_completed', {
+                        'stats': download_stats
+                    })
+                
+            except Exception as e:
+                if is_downloading:  # Only emit error if not cancelled
+                    socketio.emit('download_error', {'message': str(e)})
+            finally:
+                is_downloading = False
+                is_paused = False
+                download_thread = None
+                current_downloading = None
+                download_queue.clear()
+        
+        # Start download in background thread
+        download_thread = threading.Thread(target=download_thread_func, daemon=True)
+        download_thread.start()
+        
+        return jsonify({
+            'status': 'success',
+            'message': 'Download started'
+        })
+        
+    except Exception as e:
+        return jsonify({
+            'status': 'error',
+            'message': str(e)
+        }), 500
+
+@app.route('/api/download/pause', methods=['POST'])
+def pause_download():
+    """Pause current download."""
+    global is_paused
+    
+    if not is_downloading:
+        return jsonify({
+            'status': 'error',
+            'message': 'No download in progress'
+        }), 400
+    
+    is_paused = True
+    socketio.emit('download_paused')
+    
+    return jsonify({
+        'status': 'success',
+        'message': 'Download paused'
+    })
+
+@app.route('/api/download/resume', methods=['POST'])
+def resume_download():
+    """Resume paused download."""
+    global is_paused
+    
+    if not is_downloading:
+        return jsonify({
+            'status': 'error',
+            'message': 'No download in progress'
+        }), 400
+    
+    if not is_paused:
+        return jsonify({
+            'status': 'error',
+            'message': 'Download is not paused'
+        }), 400
+    
+    is_paused = False
+    socketio.emit('download_resumed')
+    
+    return jsonify({
+        'status': 'success',
+        'message': 'Download resumed'
+    })
+
+@app.route('/api/download/cancel', methods=['POST'])
+def cancel_download():
+    """Cancel current download."""
+    global is_downloading, is_paused, download_thread
+    
+    if not is_downloading:
+        return jsonify({
+            'status': 'error',
+            'message': 'No download in progress'
+        }), 400
+    
+    is_downloading = False
+    is_paused = False
+    
+    # Note: In a real implementation, you would need to stop the download thread
+    # This would require more sophisticated thread management
+    
+    socketio.emit('download_cancelled')
+    
+    return jsonify({
+        'status': 'success',
+        'message': 'Download cancelled'
+    })
+
+@app.route('/api/download/status')
+def get_download_status():
+    """Get detailed download status including queue and current progress."""
+    return jsonify({
+        'is_downloading': is_downloading,
+        'is_paused': is_paused,
+        'queue': [{'folder': serie.folder, 'name': serie.name or serie.folder} for serie in download_queue],
+        'current_downloading': {
+            'folder': current_downloading.folder,
+            'name': current_downloading.name or current_downloading.folder,
+            'current_episode': download_stats['current_episode'],
+            'missing_episodes': sum(len(episodes) for episodes in current_downloading.episodeDict.values())
+        } if current_downloading else None,
+        'stats': download_stats
+    })
+
+@app.route('/api/status')
+def get_status():
+    """Get current application status."""
+    return jsonify({
+        'is_scanning': is_scanning,
+        'is_downloading': is_downloading,
+        'is_paused': is_paused,
+        'directory': series_app.directory_to_search if series_app else None,
+        'series_count': len(series_app.series_list) if series_app else 0,
+        'download_queue_count': len(download_queue),
+        'current_downloading': current_downloading.name if current_downloading else None
+    })
+
+@socketio.on('connect')
+def handle_connect():
+    """Handle client connection."""
+    emit('connected', {'message': 'Connected to AniWorld server'})
+
+if __name__ == '__main__':
+    # Configure logging
+    logging.basicConfig(level=logging.INFO)
+    
+    print("Starting AniWorld Flask server...")
+    print(f"Using directory: {series_app.directory_to_search}")
+    
+    socketio.run(app, debug=True, host='0.0.0.0', port=5000)
\ No newline at end of file
diff --git a/src/server/start_server.bat b/src/server/start_server.bat
new file mode 100644
index 0000000..bfb2bcb
--- /dev/null
+++ b/src/server/start_server.bat
@@ -0,0 +1,22 @@
+@echo off
+echo Starting AniWorld Web Manager...
+echo.
+
+REM Check if environment variable is set
+if "%ANIME_DIRECTORY%"=="" (
+    echo WARNING: ANIME_DIRECTORY environment variable not set!
+    echo Using default directory: \\sshfs.r\ubuntu@192.168.178.43\media\serien\Serien
+    echo.
+    echo To set your own directory, run:
+    echo set ANIME_DIRECTORY="\\sshfs.r\ubuntu@192.168.178.43\media\serien\Serien"
+    echo.
+    pause
+)
+
+REM Change to server directory
+cd /d "%~dp0"
+
+REM Start the Flask application
+python app.py
+
+pause
\ No newline at end of file
diff --git a/src/server/start_server.sh b/src/server/start_server.sh
new file mode 100644
index 0000000..0c7180b
--- /dev/null
+++ b/src/server/start_server.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+
+echo "Starting AniWorld Web Manager..."
+echo
+
+# Check if environment variable is set
+if [ -z "$ANIME_DIRECTORY" ]; then
+    echo "WARNING: ANIME_DIRECTORY environment variable not set!"
+    echo "Using default directory: \\\\sshfs.r\\ubuntu@192.168.178.43\\media\\serien\\Serien"
+    echo
+    echo "To set your own directory, run:"
+    echo "export ANIME_DIRECTORY=\"/path/to/your/anime/directory\""
+    echo
+    read -p "Press Enter to continue..."
+fi
+
+# Change to server directory
+cd "$(dirname "$0")"
+
+# Start the Flask application
+python app.py
\ No newline at end of file
diff --git a/src/server/static/css/styles.css b/src/server/static/css/styles.css
new file mode 100644
index 0000000..1905b21
--- /dev/null
+++ b/src/server/static/css/styles.css
@@ -0,0 +1,882 @@
+/* Fluent UI Design System Variables */
+:root {
+  /* Light theme colors */
+  --color-bg-primary: #ffffff;
+  --color-bg-secondary: #faf9f8;
+  --color-bg-tertiary: #f3f2f1;
+  --color-surface: #ffffff;
+  --color-surface-hover: #f3f2f1;
+  --color-surface-pressed: #edebe9;
+  --color-text-primary: #323130;
+  --color-text-secondary: #605e5c;
+  --color-text-tertiary: #a19f9d;
+  --color-accent: #0078d4;
+  --color-accent-hover: #106ebe;
+  --color-accent-pressed: #005a9e;
+  --color-success: #107c10;
+  --color-warning: #ff8c00;
+  --color-error: #d13438;
+  --color-border: #e1dfdd;
+  --color-divider: #c8c6c4;
+  
+  /* Dark theme colors */
+  --color-bg-primary-dark: #202020;
+  --color-bg-secondary-dark: #2d2d30;
+  --color-bg-tertiary-dark: #3e3e42;
+  --color-surface-dark: #292929;
+  --color-surface-hover-dark: #3e3e42;
+  --color-surface-pressed-dark: #484848;
+  --color-text-primary-dark: #ffffff;
+  --color-text-secondary-dark: #cccccc;
+  --color-text-tertiary-dark: #969696;
+  --color-accent-dark: #60cdff;
+  --color-accent-hover-dark: #4db8e8;
+  --color-accent-pressed-dark: #3aa0d1;
+  --color-border-dark: #484644;
+  --color-divider-dark: #605e5c;
+  
+  /* Typography */
+  --font-family: 'Segoe UI', 'Segoe UI Web (West European)', -apple-system, BlinkMacSystemFont, Roboto, 'Helvetica Neue', sans-serif;
+  --font-size-caption: 12px;
+  --font-size-body: 14px;
+  --font-size-subtitle: 16px;
+  --font-size-title: 20px;
+  --font-size-large-title: 32px;
+  
+  /* Spacing */
+  --spacing-xs: 4px;
+  --spacing-sm: 8px;
+  --spacing-md: 12px;
+  --spacing-lg: 16px;
+  --spacing-xl: 20px;
+  --spacing-xxl: 24px;
+  
+  /* Border radius */
+  --border-radius-sm: 2px;
+  --border-radius-md: 4px;
+  --border-radius-lg: 6px;
+  --border-radius-xl: 8px;
+  
+  /* Shadows */
+  --shadow-card: 0 1.6px 3.6px 0 rgba(0, 0, 0, 0.132), 0 0.3px 0.9px 0 rgba(0, 0, 0, 0.108);
+  --shadow-elevated: 0 6.4px 14.4px 0 rgba(0, 0, 0, 0.132), 0 1.2px 3.6px 0 rgba(0, 0, 0, 0.108);
+  
+  /* Transitions */
+  --transition-duration: 0.15s;
+  --transition-easing: cubic-bezier(0.1, 0.9, 0.2, 1);
+}
+
+/* Dark theme */
+[data-theme="dark"] {
+  --color-bg-primary: var(--color-bg-primary-dark);
+  --color-bg-secondary: var(--color-bg-secondary-dark);
+  --color-bg-tertiary: var(--color-bg-tertiary-dark);
+  --color-surface: var(--color-surface-dark);
+  --color-surface-hover: var(--color-surface-hover-dark);
+  --color-surface-pressed: var(--color-surface-pressed-dark);
+  --color-text-primary: var(--color-text-primary-dark);
+  --color-text-secondary: var(--color-text-secondary-dark);
+  --color-text-tertiary: var(--color-text-tertiary-dark);
+  --color-accent: var(--color-accent-dark);
+  --color-accent-hover: var(--color-accent-hover-dark);
+  --color-accent-pressed: var(--color-accent-pressed-dark);
+  --color-border: var(--color-border-dark);
+  --color-divider: var(--color-divider-dark);
+}
+
+/* Base styles */
+* {
+  box-sizing: border-box;
+}
+
+html {
+  font-size: 100%;
+}
+
+body {
+  margin: 0;
+  padding: 0;
+  font-family: var(--font-family);
+  font-size: var(--font-size-body);
+  line-height: 1.5;
+  color: var(--color-text-primary);
+  background-color: var(--color-bg-primary);
+  transition: background-color var(--transition-duration) var(--transition-easing),
+              color var(--transition-duration) var(--transition-easing);
+}
+
+/* App container */
+.app-container {
+  min-height: 100vh;
+  display: flex;
+  flex-direction: column;
+}
+
+/* Header */
+.header {
+  background-color: var(--color-surface);
+  border-bottom: 1px solid var(--color-border);
+  padding: var(--spacing-lg) var(--spacing-xl);
+  box-shadow: var(--shadow-card);
+  transition: background-color var(--transition-duration) var(--transition-easing);
+}
+
+.header-content {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  max-width: 1200px;
+  margin: 0 auto;
+}
+
+.header-title {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-md);
+}
+
+.header-title i {
+  font-size: var(--font-size-title);
+  color: var(--color-accent);
+}
+
+.header-title h1 {
+  margin: 0;
+  font-size: var(--font-size-title);
+  font-weight: 600;
+  color: var(--color-text-primary);
+}
+
+.header-actions {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-md);
+}
+
+/* Main content */
+.main-content {
+  flex: 1;
+  padding: var(--spacing-xl);
+  max-width: 1200px;
+  margin: 0 auto;
+  width: 100%;
+}
+
+/* Search section */
+.search-section {
+  margin-bottom: var(--spacing-xxl);
+}
+
+.search-container {
+  margin-bottom: var(--spacing-lg);
+}
+
+.search-input-group {
+  display: flex;
+  gap: var(--spacing-sm);
+  max-width: 600px;
+}
+
+.search-input {
+  flex: 1;
+  padding: var(--spacing-md);
+  border: 1px solid var(--color-border);
+  border-radius: var(--border-radius-md);
+  font-size: var(--font-size-body);
+  background-color: var(--color-surface);
+  color: var(--color-text-primary);
+  transition: all var(--transition-duration) var(--transition-easing);
+}
+
+.search-input:focus {
+  outline: none;
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 1px var(--color-accent);
+}
+
+.search-results {
+  background-color: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--border-radius-lg);
+  padding: var(--spacing-lg);
+  box-shadow: var(--shadow-card);
+  margin-top: var(--spacing-lg);
+}
+
+.search-results h3 {
+  margin: 0 0 var(--spacing-md) 0;
+  font-size: var(--font-size-subtitle);
+  color: var(--color-text-primary);
+}
+
+.search-results-list {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-sm);
+}
+
+.search-result-item {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: var(--spacing-md);
+  background-color: var(--color-bg-secondary);
+  border-radius: var(--border-radius-md);
+  transition: background-color var(--transition-duration) var(--transition-easing);
+}
+
+.search-result-item:hover {
+  background-color: var(--color-surface-hover);
+}
+
+.search-result-name {
+  font-weight: 500;
+  color: var(--color-text-primary);
+}
+
+/* Download Queue Section */
+.download-queue-section {
+  margin-bottom: var(--spacing-xxl);
+  background-color: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--border-radius-lg);
+  box-shadow: var(--shadow-card);
+  overflow: hidden;
+}
+
+.queue-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: var(--spacing-lg);
+  background-color: var(--color-bg-secondary);
+  border-bottom: 1px solid var(--color-border);
+}
+
+.queue-header h2 {
+  margin: 0;
+  font-size: var(--font-size-subtitle);
+  color: var(--color-text-primary);
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-sm);
+}
+
+.queue-header i {
+  color: var(--color-accent);
+}
+
+.queue-progress {
+  font-size: var(--font-size-caption);
+  color: var(--color-text-secondary);
+  font-weight: 500;
+}
+
+.current-download {
+  padding: var(--spacing-lg);
+  border-bottom: 1px solid var(--color-border);
+  background-color: var(--color-surface);
+}
+
+.current-download-header {
+  margin-bottom: var(--spacing-md);
+}
+
+.current-download-header h3 {
+  margin: 0;
+  font-size: var(--font-size-body);
+  color: var(--color-text-primary);
+  font-weight: 600;
+}
+
+.current-download-item {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-lg);
+  padding: var(--spacing-md);
+  background-color: var(--color-bg-secondary);
+  border-radius: var(--border-radius-md);
+  border-left: 4px solid var(--color-accent);
+}
+
+.download-info {
+  flex: 1;
+}
+
+.serie-name {
+  font-weight: 600;
+  color: var(--color-text-primary);
+  margin-bottom: var(--spacing-xs);
+}
+
+.episode-info {
+  font-size: var(--font-size-caption);
+  color: var(--color-text-secondary);
+}
+
+.download-progress {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-sm);
+  min-width: 120px;
+}
+
+.progress-bar-mini {
+  width: 80px;
+  height: 4px;
+  background-color: var(--color-bg-tertiary);
+  border-radius: var(--border-radius-sm);
+  overflow: hidden;
+}
+
+.progress-fill-mini {
+  height: 100%;
+  background-color: var(--color-accent);
+  border-radius: var(--border-radius-sm);
+  transition: width var(--transition-duration) var(--transition-easing);
+  width: 0%;
+}
+
+.progress-text-mini {
+  font-size: var(--font-size-caption);
+  color: var(--color-text-secondary);
+  font-weight: 500;
+  min-width: 35px;
+}
+
+.queue-list-container {
+  padding: var(--spacing-lg);
+}
+
+.queue-list-container h3 {
+  margin: 0 0 var(--spacing-md) 0;
+  font-size: var(--font-size-body);
+  color: var(--color-text-primary);
+  font-weight: 600;
+}
+
+.queue-list {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-sm);
+}
+
+.queue-item {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-md);
+  padding: var(--spacing-sm) var(--spacing-md);
+  background-color: var(--color-bg-secondary);
+  border-radius: var(--border-radius-md);
+  border-left: 3px solid var(--color-divider);
+}
+
+.queue-item-index {
+  font-size: var(--font-size-caption);
+  color: var(--color-text-tertiary);
+  font-weight: 600;
+  min-width: 20px;
+}
+
+.queue-item-name {
+  flex: 1;
+  color: var(--color-text-secondary);
+}
+
+.queue-item-status {
+  font-size: var(--font-size-caption);
+  color: var(--color-text-tertiary);
+}
+
+.queue-empty {
+  text-align: center;
+  padding: var(--spacing-xl);
+  color: var(--color-text-tertiary);
+  font-style: italic;
+}
+
+/* Series section */
+.series-section {
+  margin-bottom: var(--spacing-xxl);
+}
+
+.series-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: var(--spacing-lg);
+}
+
+.series-header h2 {
+  margin: 0;
+  font-size: var(--font-size-title);
+  color: var(--color-text-primary);
+}
+
+.series-actions {
+  display: flex;
+  gap: var(--spacing-md);
+}
+
+.series-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
+  gap: var(--spacing-lg);
+}
+
+.series-card {
+  background-color: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--border-radius-lg);
+  padding: var(--spacing-lg);
+  box-shadow: var(--shadow-card);
+  transition: all var(--transition-duration) var(--transition-easing);
+  position: relative;
+}
+
+.series-card:hover {
+  box-shadow: var(--shadow-elevated);
+  transform: translateY(-1px);
+}
+
+.series-card.selected {
+  border-color: var(--color-accent);
+  background-color: var(--color-surface-hover);
+}
+
+.series-card-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: flex-start;
+  margin-bottom: var(--spacing-md);
+}
+
+.series-checkbox {
+  width: 18px;
+  height: 18px;
+  accent-color: var(--color-accent);
+}
+
+.series-info h3 {
+  margin: 0 0 var(--spacing-xs) 0;
+  font-size: var(--font-size-subtitle);
+  color: var(--color-text-primary);
+  line-height: 1.3;
+}
+
+.series-folder {
+  font-size: var(--font-size-caption);
+  color: var(--color-text-tertiary);
+  margin-bottom: var(--spacing-sm);
+}
+
+.series-stats {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-md);
+}
+
+.missing-episodes {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-xs);
+  color: var(--color-text-secondary);
+  font-size: var(--font-size-caption);
+}
+
+.missing-episodes i {
+  color: var(--color-warning);
+}
+
+/* Button styles */
+.btn {
+  display: inline-flex;
+  align-items: center;
+  gap: var(--spacing-xs);
+  padding: var(--spacing-sm) var(--spacing-md);
+  border: 1px solid transparent;
+  border-radius: var(--border-radius-md);
+  font-size: var(--font-size-body);
+  font-weight: 500;
+  text-decoration: none;
+  cursor: pointer;
+  transition: all var(--transition-duration) var(--transition-easing);
+  background-color: transparent;
+  color: var(--color-text-primary);
+}
+
+.btn:disabled {
+  opacity: 0.6;
+  cursor: not-allowed;
+}
+
+.btn-primary {
+  background-color: var(--color-accent);
+  color: white;
+}
+
+.btn-primary:hover:not(:disabled) {
+  background-color: var(--color-accent-hover);
+}
+
+.btn-primary:active {
+  background-color: var(--color-accent-pressed);
+}
+
+.btn-secondary {
+  background-color: var(--color-surface);
+  border-color: var(--color-border);
+  color: var(--color-text-primary);
+}
+
+.btn-secondary:hover:not(:disabled) {
+  background-color: var(--color-surface-hover);
+}
+
+.btn-success {
+  background-color: var(--color-success);
+  color: white;
+}
+
+.btn-success:hover:not(:disabled) {
+  background-color: #0e6b0e;
+}
+
+.btn-icon {
+  padding: var(--spacing-sm);
+  min-width: auto;
+}
+
+.btn-small {
+  padding: var(--spacing-xs) var(--spacing-sm);
+  font-size: var(--font-size-caption);
+}
+
+/* Status panel */
+.status-panel {
+  position: fixed;
+  bottom: var(--spacing-xl);
+  right: var(--spacing-xl);
+  width: 400px;
+  background-color: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--border-radius-lg);
+  box-shadow: var(--shadow-elevated);
+  z-index: 1000;
+  transition: all var(--transition-duration) var(--transition-easing);
+}
+
+.status-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: var(--spacing-md) var(--spacing-lg);
+  border-bottom: 1px solid var(--color-border);
+}
+
+.status-header h3 {
+  margin: 0;
+  font-size: var(--font-size-subtitle);
+  color: var(--color-text-primary);
+}
+
+.status-content {
+  padding: var(--spacing-lg);
+}
+
+.status-message {
+  margin-bottom: var(--spacing-md);
+  color: var(--color-text-secondary);
+}
+
+.progress-container {
+  margin-top: var(--spacing-md);
+}
+
+.progress-bar {
+  width: 100%;
+  height: 8px;
+  background-color: var(--color-bg-tertiary);
+  border-radius: var(--border-radius-sm);
+  overflow: hidden;
+}
+
+.progress-fill {
+  height: 100%;
+  background-color: var(--color-accent);
+  border-radius: var(--border-radius-sm);
+  transition: width var(--transition-duration) var(--transition-easing);
+  width: 0%;
+}
+
+.progress-text {
+  margin-top: var(--spacing-xs);
+  text-align: center;
+  font-size: var(--font-size-caption);
+  color: var(--color-text-secondary);
+}
+
+/* Toast notifications */
+.toast-container {
+  position: fixed;
+  top: var(--spacing-xl);
+  right: var(--spacing-xl);
+  z-index: 1100;
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-sm);
+}
+
+.toast {
+  background-color: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--border-radius-lg);
+  padding: var(--spacing-md) var(--spacing-lg);
+  box-shadow: var(--shadow-elevated);
+  min-width: 300px;
+  animation: slideIn var(--transition-duration) var(--transition-easing);
+}
+
+.toast.success {
+  border-left: 4px solid var(--color-success);
+}
+
+.toast.error {
+  border-left: 4px solid var(--color-error);
+}
+
+.toast.warning {
+  border-left: 4px solid var(--color-warning);
+}
+
+/* Loading overlay */
+.loading-overlay {
+  position: fixed;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  background-color: rgba(0, 0, 0, 0.5);
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  z-index: 2000;
+}
+
+.loading-spinner {
+  text-align: center;
+  color: white;
+}
+
+.loading-spinner i {
+  font-size: 48px;
+  margin-bottom: var(--spacing-md);
+}
+
+.loading-spinner p {
+  margin: 0;
+  font-size: var(--font-size-subtitle);
+}
+
+/* Modal styles */
+.modal {
+  position: fixed;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  z-index: 2000;
+  display: flex;
+  justify-content: center;
+  align-items: center;
+}
+
+.modal-overlay {
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  background-color: rgba(0, 0, 0, 0.5);
+}
+
+.modal-content {
+  position: relative;
+  background-color: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--border-radius-lg);
+  box-shadow: var(--shadow-elevated);
+  max-width: 500px;
+  width: 90%;
+  max-height: 80vh;
+  overflow: hidden;
+}
+
+.modal-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: var(--spacing-lg);
+  border-bottom: 1px solid var(--color-border);
+}
+
+.modal-header h3 {
+  margin: 0;
+  font-size: var(--font-size-subtitle);
+  color: var(--color-text-primary);
+}
+
+.modal-body {
+  padding: var(--spacing-lg);
+  overflow-y: auto;
+}
+
+.config-item {
+  margin-bottom: var(--spacing-lg);
+}
+
+.config-item:last-child {
+  margin-bottom: 0;
+}
+
+.config-item label {
+  display: block;
+  font-weight: 500;
+  color: var(--color-text-primary);
+  margin-bottom: var(--spacing-xs);
+}
+
+.config-value {
+  padding: var(--spacing-sm);
+  background-color: var(--color-bg-secondary);
+  border: 1px solid var(--color-border);
+  border-radius: var(--border-radius-md);
+  font-family: monospace;
+  font-size: var(--font-size-caption);
+  color: var(--color-text-secondary);
+  word-break: break-all;
+}
+
+.status-indicator {
+  display: inline-block;
+  width: 8px;
+  height: 8px;
+  border-radius: 50%;
+  background-color: var(--color-error);
+  margin-right: var(--spacing-xs);
+}
+
+.status-indicator.connected {
+  background-color: var(--color-success);
+}
+
+.download-controls {
+  display: flex;
+  gap: var(--spacing-sm);
+  margin-top: var(--spacing-md);
+  justify-content: center;
+}
+
+/* Utility classes */
+.hidden {
+  display: none !important;
+}
+
+.text-center {
+  text-align: center;
+}
+
+.mb-0 { margin-bottom: 0 !important; }
+.mb-1 { margin-bottom: var(--spacing-xs) !important; }
+.mb-2 { margin-bottom: var(--spacing-sm) !important; }
+.mb-3 { margin-bottom: var(--spacing-md) !important; }
+.mb-4 { margin-bottom: var(--spacing-lg) !important; }
+
+/* Animations */
+@keyframes slideIn {
+  from {
+    transform: translateX(100%);
+    opacity: 0;
+  }
+  to {
+    transform: translateX(0);
+    opacity: 1;
+  }
+}
+
+@keyframes fadeIn {
+  from { opacity: 0; }
+  to { opacity: 1; }
+}
+
+@keyframes fadeOut {
+  from { opacity: 1; }
+  to { opacity: 0; }
+}
+
+/* Responsive design */
+@media (max-width: 768px) {
+  .header-content {
+    flex-direction: column;
+    gap: var(--spacing-md);
+  }
+  
+  .header-title {
+    text-align: center;
+  }
+  
+  .main-content {
+    padding: var(--spacing-md);
+  }
+  
+  .series-header {
+    flex-direction: column;
+    gap: var(--spacing-md);
+    align-items: stretch;
+  }
+  
+  .series-actions {
+    justify-content: center;
+  }
+  
+  .series-grid {
+    grid-template-columns: 1fr;
+  }
+  
+  .status-panel {
+    bottom: var(--spacing-md);
+    right: var(--spacing-md);
+    left: var(--spacing-md);
+    width: auto;
+  }
+  
+  .toast-container {
+    top: var(--spacing-md);
+    right: var(--spacing-md);
+    left: var(--spacing-md);
+  }
+  
+  .toast {
+    min-width: auto;
+  }
+  
+  .current-download-item {
+    flex-direction: column;
+    align-items: stretch;
+    gap: var(--spacing-sm);
+  }
+  
+  .download-progress {
+    justify-content: space-between;
+  }
+  
+  .queue-item {
+    flex-direction: column;
+    align-items: stretch;
+    gap: var(--spacing-xs);
+  }
+  
+  .queue-item-index {
+    min-width: auto;
+  }
+}
\ No newline at end of file
diff --git a/src/server/static/js/app.js b/src/server/static/js/app.js
new file mode 100644
index 0000000..77a1c32
--- /dev/null
+++ b/src/server/static/js/app.js
@@ -0,0 +1,746 @@
+/**
+ * AniWorld Manager - Main JavaScript Application
+ * Implements Fluent UI design principles with modern web app functionality
+ */
+
+class AniWorldApp {
+    constructor() {
+        this.socket = null;
+        this.selectedSeries = new Set();
+        this.seriesData = [];
+        this.isConnected = false;
+        this.isDownloading = false;
+        this.isPaused = false;
+        this.localization = new Localization();
+        
+        this.init();
+    }
+
+    init() {
+        this.initSocket();
+        this.bindEvents();
+        this.loadSeries();
+        this.initTheme();
+        this.updateConnectionStatus();
+    }
+
+    initSocket() {
+        this.socket = io();
+        
+        this.socket.on('connect', () => {
+            this.isConnected = true;
+            console.log('Connected to server');
+            this.showToast(this.localization.getText('connected-server'), 'success');
+            this.updateConnectionStatus();
+        });
+
+        this.socket.on('disconnect', () => {
+            this.isConnected = false;
+            console.log('Disconnected from server');
+            this.showToast(this.localization.getText('disconnected-server'), 'warning');
+            this.updateConnectionStatus();
+        });
+
+        // Scan events
+        this.socket.on('scan_started', () => {
+            this.showStatus('Scanning series...', true);
+        });
+
+        this.socket.on('scan_progress', (data) => {
+            this.updateStatus(`Scanning: ${data.folder} (${data.counter})`);
+        });
+
+        this.socket.on('scan_completed', () => {
+            this.hideStatus();
+            this.showToast('Scan completed successfully', 'success');
+            this.loadSeries();
+        });
+
+        this.socket.on('scan_error', (data) => {
+            this.hideStatus();
+            this.showToast(`Scan error: ${data.message}`, 'error');
+        });
+
+        // Download events
+        this.socket.on('download_started', (data) => {
+            this.isDownloading = true;
+            this.isPaused = false;
+            this.showDownloadQueue(data);
+            this.showStatus(`Starting download of ${data.total_series} series...`, true, true);
+        });
+
+        this.socket.on('download_progress', (data) => {
+            if (data.total_bytes) {
+                const percent = ((data.downloaded_bytes || 0) / data.total_bytes * 100).toFixed(1);
+                this.updateProgress(percent, `Downloading: ${percent}%`);
+            } else {
+                this.updateStatus(`Downloading: ${data.percent || '0%'}`);
+            }
+        });
+
+        this.socket.on('download_completed', (data) => {
+            this.isDownloading = false;
+            this.isPaused = false;
+            this.hideDownloadQueue();
+            this.hideStatus();
+            this.showToast(this.localization.getText('download-completed'), 'success');
+            this.loadSeries();
+            this.clearSelection();
+        });
+
+        this.socket.on('download_error', (data) => {
+            this.isDownloading = false;
+            this.isPaused = false;
+            this.hideDownloadQueue();
+            this.hideStatus();
+            this.showToast(`${this.localization.getText('download-failed')}: ${data.message}`, 'error');
+        });
+
+        // Download queue events
+        this.socket.on('download_queue_update', (data) => {
+            this.updateDownloadQueue(data);
+        });
+
+        this.socket.on('download_episode_update', (data) => {
+            this.updateCurrentEpisode(data);
+        });
+
+        this.socket.on('download_series_completed', (data) => {
+            this.updateDownloadProgress(data);
+        });
+
+        // Download control events
+        this.socket.on('download_paused', () => {
+            this.isPaused = true;
+            this.updateStatus(this.localization.getText('paused'));
+        });
+
+        this.socket.on('download_resumed', () => {
+            this.isPaused = false;
+            this.updateStatus(this.localization.getText('downloading'));
+        });
+
+        this.socket.on('download_cancelled', () => {
+            this.isDownloading = false;
+            this.isPaused = false;
+            this.hideDownloadQueue();
+            this.hideStatus();
+            this.showToast('Download cancelled', 'warning');
+        });
+    }
+
+    bindEvents() {
+        // Theme toggle
+        document.getElementById('theme-toggle').addEventListener('click', () => {
+            this.toggleTheme();
+        });
+
+        // Search functionality
+        const searchInput = document.getElementById('search-input');
+        const searchBtn = document.getElementById('search-btn');
+        const clearSearch = document.getElementById('clear-search');
+
+        searchBtn.addEventListener('click', () => {
+            this.performSearch();
+        });
+
+        searchInput.addEventListener('keypress', (e) => {
+            if (e.key === 'Enter') {
+                this.performSearch();
+            }
+        });
+
+        clearSearch.addEventListener('click', () => {
+            searchInput.value = '';
+            this.hideSearchResults();
+        });
+
+        // Series management
+        document.getElementById('select-all').addEventListener('click', () => {
+            this.toggleSelectAll();
+        });
+
+        document.getElementById('download-selected').addEventListener('click', () => {
+            this.downloadSelected();
+        });
+
+        // Rescan
+        document.getElementById('rescan-btn').addEventListener('click', () => {
+            this.rescanSeries();
+        });
+
+        // Configuration modal
+        document.getElementById('config-btn').addEventListener('click', () => {
+            this.showConfigModal();
+        });
+
+        document.getElementById('close-config').addEventListener('click', () => {
+            this.hideConfigModal();
+        });
+
+        document.querySelector('#config-modal .modal-overlay').addEventListener('click', () => {
+            this.hideConfigModal();
+        });
+
+        // Status panel
+        document.getElementById('close-status').addEventListener('click', () => {
+            this.hideStatus();
+        });
+
+        // Download controls
+        document.getElementById('pause-download').addEventListener('click', () => {
+            this.pauseDownload();
+        });
+
+        document.getElementById('resume-download').addEventListener('click', () => {
+            this.resumeDownload();
+        });
+
+        document.getElementById('cancel-download').addEventListener('click', () => {
+            this.cancelDownload();
+        });
+    }
+
+    initTheme() {
+        const savedTheme = localStorage.getItem('theme') || 'light';
+        this.setTheme(savedTheme);
+    }
+
+    setTheme(theme) {
+        document.documentElement.setAttribute('data-theme', theme);
+        localStorage.setItem('theme', theme);
+        
+        const themeIcon = document.querySelector('#theme-toggle i');
+        themeIcon.className = theme === 'light' ? 'fas fa-moon' : 'fas fa-sun';
+    }
+
+    toggleTheme() {
+        const currentTheme = document.documentElement.getAttribute('data-theme') || 'light';
+        const newTheme = currentTheme === 'light' ? 'dark' : 'light';
+        this.setTheme(newTheme);
+    }
+
+    async loadSeries() {
+        try {
+            this.showLoading();
+            
+            const response = await fetch('/api/series');
+            const data = await response.json();
+            
+            if (data.status === 'success') {
+                this.seriesData = data.series;
+                this.renderSeries();
+            } else {
+                this.showToast(`Error loading series: ${data.message}`, 'error');
+            }
+        } catch (error) {
+            console.error('Error loading series:', error);
+            this.showToast('Failed to load series', 'error');
+        } finally {
+            this.hideLoading();
+        }
+    }
+
+    renderSeries() {
+        const grid = document.getElementById('series-grid');
+        
+        if (this.seriesData.length === 0) {
+            grid.innerHTML = `
+                <div class="text-center" style="grid-column: 1 / -1; padding: 2rem;">
+                    <i class="fas fa-tv" style="font-size: 48px; color: var(--color-text-tertiary); margin-bottom: 1rem;"></i>
+                    <p style="color: var(--color-text-secondary);">No series found. Try searching for anime or rescanning your directory.</p>
+                </div>
+            `;
+            return;
+        }
+
+        grid.innerHTML = this.seriesData.map(serie => this.createSerieCard(serie)).join('');
+        
+        // Bind checkbox events
+        grid.querySelectorAll('.series-checkbox').forEach(checkbox => {
+            checkbox.addEventListener('change', (e) => {
+                this.toggleSerieSelection(e.target.dataset.folder, e.target.checked);
+            });
+        });
+    }
+
+    createSerieCard(serie) {
+        const isSelected = this.selectedSeries.has(serie.folder);
+        
+        return `
+            <div class="series-card ${isSelected ? 'selected' : ''}" data-folder="${serie.folder}">
+                <div class="series-card-header">
+                    <input type="checkbox" 
+                           class="series-checkbox" 
+                           data-folder="${serie.folder}"
+                           ${isSelected ? 'checked' : ''}>
+                    <div class="series-info">
+                        <h3>${this.escapeHtml(serie.name)}</h3>
+                        <div class="series-folder">${this.escapeHtml(serie.folder)}</div>
+                    </div>
+                </div>
+                <div class="series-stats">
+                    <div class="missing-episodes">
+                        <i class="fas fa-exclamation-triangle"></i>
+                        <span>${serie.missing_episodes} missing episodes</span>
+                    </div>
+                    <span class="series-site">${serie.site}</span>
+                </div>
+            </div>
+        `;
+    }
+
+    toggleSerieSelection(folder, selected) {
+        if (selected) {
+            this.selectedSeries.add(folder);
+        } else {
+            this.selectedSeries.delete(folder);
+        }
+
+        this.updateSelectionUI();
+    }
+
+    updateSelectionUI() {
+        const downloadBtn = document.getElementById('download-selected');
+        const selectAllBtn = document.getElementById('select-all');
+        
+        downloadBtn.disabled = this.selectedSeries.size === 0;
+        
+        if (this.selectedSeries.size === 0) {
+            selectAllBtn.innerHTML = '<i class="fas fa-check-double"></i><span>Select All</span>';
+        } else if (this.selectedSeries.size === this.seriesData.length) {
+            selectAllBtn.innerHTML = '<i class="fas fa-times"></i><span>Deselect All</span>';
+        } else {
+            selectAllBtn.innerHTML = '<i class="fas fa-check-double"></i><span>Select All</span>';
+        }
+
+        // Update card appearances
+        document.querySelectorAll('.series-card').forEach(card => {
+            const folder = card.dataset.folder;
+            const isSelected = this.selectedSeries.has(folder);
+            card.classList.toggle('selected', isSelected);
+        });
+    }
+
+    toggleSelectAll() {
+        if (this.selectedSeries.size === this.seriesData.length) {
+            // Deselect all
+            this.selectedSeries.clear();
+            document.querySelectorAll('.series-checkbox').forEach(cb => cb.checked = false);
+        } else {
+            // Select all
+            this.selectedSeries.clear();
+            this.seriesData.forEach(serie => this.selectedSeries.add(serie.folder));
+            document.querySelectorAll('.series-checkbox').forEach(cb => cb.checked = true);
+        }
+        
+        this.updateSelectionUI();
+    }
+
+    clearSelection() {
+        this.selectedSeries.clear();
+        document.querySelectorAll('.series-checkbox').forEach(cb => cb.checked = false);
+        this.updateSelectionUI();
+    }
+
+    async performSearch() {
+        const searchInput = document.getElementById('search-input');
+        const query = searchInput.value.trim();
+        
+        if (!query) {
+            this.showToast('Please enter a search term', 'warning');
+            return;
+        }
+
+        try {
+            this.showLoading();
+            
+            const response = await fetch('/api/search', {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/json',
+                },
+                body: JSON.stringify({ query })
+            });
+
+            const data = await response.json();
+            
+            if (data.status === 'success') {
+                this.displaySearchResults(data.results);
+            } else {
+                this.showToast(`Search error: ${data.message}`, 'error');
+            }
+        } catch (error) {
+            console.error('Search error:', error);
+            this.showToast('Search failed', 'error');
+        } finally {
+            this.hideLoading();
+        }
+    }
+
+    displaySearchResults(results) {
+        const resultsContainer = document.getElementById('search-results');
+        const resultsList = document.getElementById('search-results-list');
+        
+        if (results.length === 0) {
+            resultsContainer.classList.add('hidden');
+            this.showToast('No search results found', 'warning');
+            return;
+        }
+
+        resultsList.innerHTML = results.map(result => `
+            <div class="search-result-item">
+                <span class="search-result-name">${this.escapeHtml(result.name)}</span>
+                <button class="btn btn-small btn-primary" onclick="app.addSeries('${this.escapeHtml(result.link)}', '${this.escapeHtml(result.name)}')">
+                    <i class="fas fa-plus"></i>
+                    Add
+                </button>
+            </div>
+        `).join('');
+
+        resultsContainer.classList.remove('hidden');
+    }
+
+    hideSearchResults() {
+        document.getElementById('search-results').classList.add('hidden');
+    }
+
+    async addSeries(link, name) {
+        try {
+            const response = await fetch('/api/add_series', {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/json',
+                },
+                body: JSON.stringify({ link, name })
+            });
+
+            const data = await response.json();
+            
+            if (data.status === 'success') {
+                this.showToast(data.message, 'success');
+                this.loadSeries();
+                this.hideSearchResults();
+                document.getElementById('search-input').value = '';
+            } else {
+                this.showToast(`Error adding series: ${data.message}`, 'error');
+            }
+        } catch (error) {
+            console.error('Error adding series:', error);
+            this.showToast('Failed to add series', 'error');
+        }
+    }
+
+    async downloadSelected() {
+        if (this.selectedSeries.size === 0) {
+            this.showToast('No series selected', 'warning');
+            return;
+        }
+
+        try {
+            const folders = Array.from(this.selectedSeries);
+            
+            const response = await fetch('/api/download', {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/json',
+                },
+                body: JSON.stringify({ folders })
+            });
+
+            const data = await response.json();
+            
+            if (data.status === 'success') {
+                this.showToast('Download started', 'success');
+            } else {
+                this.showToast(`Download error: ${data.message}`, 'error');
+            }
+        } catch (error) {
+            console.error('Download error:', error);
+            this.showToast('Failed to start download', 'error');
+        }
+    }
+
+    async rescanSeries() {
+        try {
+            const response = await fetch('/api/rescan', {
+                method: 'POST'
+            });
+
+            const data = await response.json();
+            
+            if (data.status === 'success') {
+                this.showToast('Rescan started', 'success');
+            } else {
+                this.showToast(`Rescan error: ${data.message}`, 'error');
+            }
+        } catch (error) {
+            console.error('Rescan error:', error);
+            this.showToast('Failed to start rescan', 'error');
+        }
+    }
+
+    showStatus(message, showProgress = false, showControls = false) {
+        const panel = document.getElementById('status-panel');
+        const messageEl = document.getElementById('status-message');
+        const progressContainer = document.getElementById('progress-container');
+        const controlsContainer = document.getElementById('download-controls');
+        
+        messageEl.textContent = message;
+        progressContainer.classList.toggle('hidden', !showProgress);
+        controlsContainer.classList.toggle('hidden', !showControls);
+        
+        if (showProgress) {
+            this.updateProgress(0);
+        }
+        
+        panel.classList.remove('hidden');
+    }
+
+    updateStatus(message) {
+        document.getElementById('status-message').textContent = message;
+    }
+
+    updateProgress(percent, message = null) {
+        const fill = document.getElementById('progress-fill');
+        const text = document.getElementById('progress-text');
+        
+        fill.style.width = `${percent}%`;
+        text.textContent = message || `${percent}%`;
+    }
+
+    hideStatus() {
+        document.getElementById('status-panel').classList.add('hidden');
+    }
+
+    showLoading() {
+        document.getElementById('loading-overlay').classList.remove('hidden');
+    }
+
+    hideLoading() {
+        document.getElementById('loading-overlay').classList.add('hidden');
+    }
+
+    showToast(message, type = 'info') {
+        const container = document.getElementById('toast-container');
+        const toast = document.createElement('div');
+        
+        toast.className = `toast ${type}`;
+        toast.innerHTML = `
+            <div style="display: flex; justify-content: space-between; align-items: center;">
+                <span>${this.escapeHtml(message)}</span>
+                <button onclick="this.parentElement.parentElement.remove()" style="background: none; border: none; color: var(--color-text-secondary); cursor: pointer; padding: 0; margin-left: 1rem;">
+                    <i class="fas fa-times"></i>
+                </button>
+            </div>
+        `;
+        
+        container.appendChild(toast);
+        
+        // Auto-remove after 5 seconds
+        setTimeout(() => {
+            if (toast.parentElement) {
+                toast.remove();
+            }
+        }, 5000);
+    }
+
+    escapeHtml(text) {
+        const div = document.createElement('div');
+        div.textContent = text;
+        return div.innerHTML;
+    }
+
+    updateConnectionStatus() {
+        const indicator = document.getElementById('connection-status-display');
+        if (indicator) {
+            const statusIndicator = indicator.querySelector('.status-indicator');
+            const statusText = indicator.querySelector('.status-text');
+            
+            if (this.isConnected) {
+                statusIndicator.classList.add('connected');
+                statusText.textContent = this.localization.getText('connected');
+            } else {
+                statusIndicator.classList.remove('connected');
+                statusText.textContent = this.localization.getText('disconnected');
+            }
+        }
+    }
+
+    async showConfigModal() {
+        const modal = document.getElementById('config-modal');
+        
+        try {
+            // Load current status
+            const response = await fetch('/api/status');
+            const data = await response.json();
+            
+            document.getElementById('anime-directory-display').textContent = data.directory || 'Not configured';
+            document.getElementById('series-count-display').textContent = data.series_count || '0';
+            
+            modal.classList.remove('hidden');
+        } catch (error) {
+            console.error('Error loading configuration:', error);
+            this.showToast('Failed to load configuration', 'error');
+        }
+    }
+
+    hideConfigModal() {
+        document.getElementById('config-modal').classList.add('hidden');
+    }
+
+    async pauseDownload() {
+        if (!this.isDownloading || this.isPaused) return;
+        
+        try {
+            const response = await fetch('/api/download/pause', { method: 'POST' });
+            const data = await response.json();
+            
+            if (data.status === 'success') {
+                document.getElementById('pause-download').classList.add('hidden');
+                document.getElementById('resume-download').classList.remove('hidden');
+                this.showToast('Download paused', 'warning');
+            } else {
+                this.showToast(`Pause failed: ${data.message}`, 'error');
+            }
+        } catch (error) {
+            console.error('Pause error:', error);
+            this.showToast('Failed to pause download', 'error');
+        }
+    }
+
+    async resumeDownload() {
+        if (!this.isDownloading || !this.isPaused) return;
+        
+        try {
+            const response = await fetch('/api/download/resume', { method: 'POST' });
+            const data = await response.json();
+            
+            if (data.status === 'success') {
+                document.getElementById('pause-download').classList.remove('hidden');
+                document.getElementById('resume-download').classList.add('hidden');
+                this.showToast('Download resumed', 'success');
+            } else {
+                this.showToast(`Resume failed: ${data.message}`, 'error');
+            }
+        } catch (error) {
+            console.error('Resume error:', error);
+            this.showToast('Failed to resume download', 'error');
+        }
+    }
+
+    async cancelDownload() {
+        if (!this.isDownloading) return;
+        
+        if (confirm('Are you sure you want to cancel the download?')) {
+            try {
+                const response = await fetch('/api/download/cancel', { method: 'POST' });
+                const data = await response.json();
+                
+                if (data.status === 'success') {
+                    this.showToast('Download cancelled', 'warning');
+                } else {
+                    this.showToast(`Cancel failed: ${data.message}`, 'error');
+                }
+            } catch (error) {
+                console.error('Cancel error:', error);
+                this.showToast('Failed to cancel download', 'error');
+            }
+        }
+    }
+
+    showDownloadQueue(data) {
+        const queueSection = document.getElementById('download-queue-section');
+        const queueProgress = document.getElementById('queue-progress');
+        
+        queueProgress.textContent = `0/${data.total_series} series`;
+        this.updateDownloadQueue({
+            queue: data.queue || [],
+            current_downloading: null,
+            stats: {
+                completed_series: 0,
+                total_series: data.total_series
+            }
+        });
+        
+        queueSection.classList.remove('hidden');
+    }
+
+    hideDownloadQueue() {
+        const queueSection = document.getElementById('download-queue-section');
+        const currentDownload = document.getElementById('current-download');
+        
+        queueSection.classList.add('hidden');
+        currentDownload.classList.add('hidden');
+    }
+
+    updateDownloadQueue(data) {
+        const queueList = document.getElementById('queue-list');
+        const currentDownload = document.getElementById('current-download');
+        const queueProgress = document.getElementById('queue-progress');
+        
+        // Update overall progress
+        if (data.stats) {
+            queueProgress.textContent = `${data.stats.completed_series}/${data.stats.total_series} series`;
+        }
+        
+        // Update current downloading
+        if (data.current_downloading) {
+            currentDownload.classList.remove('hidden');
+            document.getElementById('current-serie-name').textContent = data.current_downloading.name;
+            document.getElementById('current-episode').textContent = `${data.current_downloading.missing_episodes} episodes remaining`;
+        } else {
+            currentDownload.classList.add('hidden');
+        }
+        
+        // Update queue list
+        if (data.queue && data.queue.length > 0) {
+            queueList.innerHTML = data.queue.map((serie, index) => `
+                <div class="queue-item">
+                    <div class="queue-item-index">${index + 1}</div>
+                    <div class="queue-item-name">${this.escapeHtml(serie.name)}</div>
+                    <div class="queue-item-status">Waiting</div>
+                </div>
+            `).join('');
+        } else {
+            queueList.innerHTML = '<div class="queue-empty">No series in queue</div>';
+        }
+    }
+
+    updateCurrentEpisode(data) {
+        const currentEpisode = document.getElementById('current-episode');
+        const progressFill = document.getElementById('current-progress-fill');
+        const progressText = document.getElementById('current-progress-text');
+        
+        if (currentEpisode && data.episode) {
+            currentEpisode.textContent = `${data.episode} (${data.episode_progress})`;
+        }
+        
+        // Update mini progress bar based on overall progress
+        if (data.overall_progress && progressFill && progressText) {
+            const [current, total] = data.overall_progress.split('/').map(n => parseInt(n));
+            const percent = total > 0 ? (current / total * 100).toFixed(1) : 0;
+            
+            progressFill.style.width = `${percent}%`;
+            progressText.textContent = `${percent}%`;
+        }
+    }
+
+    updateDownloadProgress(data) {
+        const queueProgress = document.getElementById('queue-progress');
+        
+        if (queueProgress && data.completed_series && data.total_series) {
+            queueProgress.textContent = `${data.completed_series}/${data.total_series} series`;
+        }
+        
+        this.showToast(`Completed: ${data.serie}`, 'success');
+    }
+}
+
+// Initialize the application when DOM is loaded
+document.addEventListener('DOMContentLoaded', () => {
+    window.app = new AniWorldApp();
+});
+
+// Global functions for inline event handlers
+window.app = null;
\ No newline at end of file
diff --git a/src/server/static/js/localization.js b/src/server/static/js/localization.js
new file mode 100644
index 0000000..ce864ce
--- /dev/null
+++ b/src/server/static/js/localization.js
@@ -0,0 +1,236 @@
+/**
+ * Localization support for AniWorld Manager
+ * Implements resource-based text management for easy translation
+ */
+
+class Localization {
+    constructor() {
+        this.currentLanguage = 'en';
+        this.fallbackLanguage = 'en';
+        this.translations = {};
+        this.loadTranslations();
+    }
+
+    loadTranslations() {
+        // English (default)
+        this.translations.en = {
+            // Header
+            'config-title': 'Configuration',
+            'toggle-theme': 'Toggle theme',
+            'rescan': 'Rescan',
+
+            // Search
+            'search-placeholder': 'Search for anime...',
+            'search-results': 'Search Results',
+            'no-results': 'No results found',
+            'add': 'Add',
+
+            // Series
+            'series-collection': 'Series Collection',
+            'select-all': 'Select All',
+            'deselect-all': 'Deselect All',
+            'download-selected': 'Download Selected',
+            'missing-episodes': 'missing episodes',
+
+            // Configuration
+            'anime-directory': 'Anime Directory',
+            'series-count': 'Series Count',
+            'connection-status': 'Connection Status',
+            'connected': 'Connected',
+            'disconnected': 'Disconnected',
+
+            // Download controls
+            'pause': 'Pause',
+            'resume': 'Resume',
+            'cancel': 'Cancel',
+            'downloading': 'Downloading',
+            'paused': 'Paused',
+
+            // Download queue
+            'download-queue': 'Download Queue',
+            'currently-downloading': 'Currently Downloading',
+            'queued-series': 'Queued Series',
+
+            // Status messages
+            'connected-server': 'Connected to server',
+            'disconnected-server': 'Disconnected from server',
+            'scan-started': 'Scan started',
+            'scan-completed': 'Scan completed successfully',
+            'download-started': 'Download started',
+            'download-completed': 'Download completed successfully',
+            'series-added': 'Series added successfully',
+
+            // Error messages
+            'search-failed': 'Search failed',
+            'download-failed': 'Download failed',
+            'scan-failed': 'Scan failed',
+            'connection-failed': 'Connection failed',
+
+            // General
+            'loading': 'Loading...',
+            'close': 'Close',
+            'ok': 'OK',
+            'cancel-action': 'Cancel'
+        };
+
+        // German
+        this.translations.de = {
+            // Header
+            'config-title': 'Konfiguration',
+            'toggle-theme': 'Design wechseln',
+            'rescan': 'Neu scannen',
+
+            // Search
+            'search-placeholder': 'Nach Anime suchen...',
+            'search-results': 'Suchergebnisse',
+            'no-results': 'Keine Ergebnisse gefunden',
+            'add': 'Hinzufügen',
+
+            // Series
+            'series-collection': 'Serien-Sammlung',
+            'select-all': 'Alle auswählen',
+            'deselect-all': 'Alle abwählen',
+            'download-selected': 'Ausgewählte herunterladen',
+            'missing-episodes': 'fehlende Episoden',
+
+            // Configuration
+            'anime-directory': 'Anime-Verzeichnis',
+            'series-count': 'Anzahl Serien',
+            'connection-status': 'Verbindungsstatus',
+            'connected': 'Verbunden',
+            'disconnected': 'Getrennt',
+
+            // Download controls
+            'pause': 'Pausieren',
+            'resume': 'Fortsetzen',
+            'cancel': 'Abbrechen',
+            'downloading': 'Herunterladen',
+            'paused': 'Pausiert',
+
+            // Download queue
+            'download-queue': 'Download-Warteschlange',
+            'currently-downloading': 'Wird heruntergeladen',
+            'queued-series': 'Warteschlange',
+
+            // Status messages
+            'connected-server': 'Mit Server verbunden',
+            'disconnected-server': 'Verbindung zum Server getrennt',
+            'scan-started': 'Scan gestartet',
+            'scan-completed': 'Scan erfolgreich abgeschlossen',
+            'download-started': 'Download gestartet',
+            'download-completed': 'Download erfolgreich abgeschlossen',
+            'series-added': 'Serie erfolgreich hinzugefügt',
+
+            // Error messages
+            'search-failed': 'Suche fehlgeschlagen',
+            'download-failed': 'Download fehlgeschlagen',
+            'scan-failed': 'Scan fehlgeschlagen',
+            'connection-failed': 'Verbindung fehlgeschlagen',
+
+            // General
+            'loading': 'Wird geladen...',
+            'close': 'Schließen',
+            'ok': 'OK',
+            'cancel-action': 'Abbrechen'
+        };
+
+        // Load saved language preference
+        const savedLanguage = localStorage.getItem('language') || this.detectLanguage();
+        this.setLanguage(savedLanguage);
+    }
+
+    detectLanguage() {
+        const browserLang = navigator.language || navigator.userLanguage;
+        const langCode = browserLang.split('-')[0];
+        return this.translations[langCode] ? langCode : this.fallbackLanguage;
+    }
+
+    setLanguage(langCode) {
+        if (this.translations[langCode]) {
+            this.currentLanguage = langCode;
+            localStorage.setItem('language', langCode);
+            this.updatePageTexts();
+        }
+    }
+
+    getText(key, fallback = key) {
+        const translation = this.translations[this.currentLanguage];
+        if (translation && translation[key]) {
+            return translation[key];
+        }
+
+        // Try fallback language
+        const fallbackTranslation = this.translations[this.fallbackLanguage];
+        if (fallbackTranslation && fallbackTranslation[key]) {
+            return fallbackTranslation[key];
+        }
+
+        return fallback;
+    }
+
+    updatePageTexts() {
+        // Update all elements with data-text attributes
+        document.querySelectorAll('[data-text]').forEach(element => {
+            const key = element.getAttribute('data-text');
+            const text = this.getText(key);
+            
+            if (element.tagName === 'INPUT' && element.type === 'text') {
+                element.placeholder = text;
+            } else {
+                element.textContent = text;
+            }
+        });
+
+        // Update specific elements that need special handling
+        this.updateSearchPlaceholder();
+        this.updateDynamicTexts();
+    }
+
+    updateSearchPlaceholder() {
+        const searchInput = document.getElementById('search-input');
+        if (searchInput) {
+            searchInput.placeholder = this.getText('search-placeholder');
+        }
+    }
+
+    updateDynamicTexts() {
+        // Update any dynamically generated content
+        const selectAllBtn = document.getElementById('select-all');
+        if (selectAllBtn && window.app) {
+            const selectedCount = window.app.selectedSeries ? window.app.selectedSeries.size : 0;
+            const totalCount = window.app.seriesData ? window.app.seriesData.length : 0;
+            
+            if (selectedCount === totalCount && totalCount > 0) {
+                selectAllBtn.innerHTML = `<i class="fas fa-times"></i><span>${this.getText('deselect-all')}</span>`;
+            } else {
+                selectAllBtn.innerHTML = `<i class="fas fa-check-double"></i><span>${this.getText('select-all')}</span>`;
+            }
+        }
+    }
+
+    getAvailableLanguages() {
+        return Object.keys(this.translations).map(code => ({
+            code: code,
+            name: this.getLanguageName(code)
+        }));
+    }
+
+    getLanguageName(code) {
+        const names = {
+            'en': 'English',
+            'de': 'Deutsch'
+        };
+        return names[code] || code.toUpperCase();
+    }
+
+    formatMessage(key, ...args) {
+        let message = this.getText(key);
+        args.forEach((arg, index) => {
+            message = message.replace(`{${index}}`, arg);
+        });
+        return message;
+    }
+}
+
+// Export for use in other modules
+window.Localization = Localization;
\ No newline at end of file
diff --git a/src/server/templates/index.html b/src/server/templates/index.html
new file mode 100644
index 0000000..be1df08
--- /dev/null
+++ b/src/server/templates/index.html
@@ -0,0 +1,201 @@
+<!DOCTYPE html>
+<html lang="en" data-theme="light">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>AniWorld Manager</title>
+    <link rel="stylesheet" href="{{ url_for('static', filename='css/styles.css') }}">
+    <link href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.0.0/css/all.min.css" rel="stylesheet">
+</head>
+<body>
+    <div class="app-container">
+        <!-- Header -->
+        <header class="header">
+            <div class="header-content">
+                <div class="header-title">
+                    <i class="fas fa-play-circle"></i>
+                    <h1>AniWorld Manager</h1>
+                </div>
+                <div class="header-actions">
+                    <button id="config-btn" class="btn btn-secondary" title="Show configuration">
+                        <i class="fas fa-cog"></i>
+                        <span data-text="config-title">Config</span>
+                    </button>
+                    <button id="theme-toggle" class="btn btn-icon" title="Toggle theme" data-title="toggle-theme">
+                        <i class="fas fa-moon"></i>
+                    </button>
+                    <button id="rescan-btn" class="btn btn-primary">
+                        <i class="fas fa-sync-alt"></i>
+                        <span data-text="rescan">Rescan</span>
+                    </button>
+                </div>
+            </div>
+        </header>
+
+        <!-- Main content -->
+        <main class="main-content">
+            <!-- Search section -->
+            <section class="search-section">
+                <div class="search-container">
+                    <div class="search-input-group">
+                        <input type="text" id="search-input" data-text="search-placeholder" placeholder="Search for anime..." class="search-input">
+                        <button id="search-btn" class="btn btn-primary">
+                            <i class="fas fa-search"></i>
+                        </button>
+                        <button id="clear-search" class="btn btn-secondary">
+                            <i class="fas fa-times"></i>
+                        </button>
+                    </div>
+                </div>
+                
+                <!-- Search results -->
+                <div id="search-results" class="search-results hidden">
+                    <h3>Search Results</h3>
+                    <div id="search-results-list" class="search-results-list"></div>
+                </div>
+            </section>
+
+            <!-- Download Queue Section -->
+            <section id="download-queue-section" class="download-queue-section hidden">
+                <div class="queue-header">
+                    <h2>
+                        <i class="fas fa-download"></i>
+                        <span data-text="download-queue">Download Queue</span>
+                    </h2>
+                    <div class="queue-stats">
+                        <span id="queue-progress" class="queue-progress">0/0 series</span>
+                    </div>
+                </div>
+
+                <!-- Current Download -->
+                <div id="current-download" class="current-download hidden">
+                    <div class="current-download-header">
+                        <h3 data-text="currently-downloading">Currently Downloading</h3>
+                    </div>
+                    <div class="current-download-item">
+                        <div class="download-info">
+                            <div id="current-serie-name" class="serie-name">-</div>
+                            <div id="current-episode" class="episode-info">-</div>
+                        </div>
+                        <div class="download-progress">
+                            <div class="progress-bar-mini">
+                                <div id="current-progress-fill" class="progress-fill-mini"></div>
+                            </div>
+                            <div id="current-progress-text" class="progress-text-mini">0%</div>
+                        </div>
+                    </div>
+                </div>
+
+                <!-- Queue List -->
+                <div id="queue-list-container" class="queue-list-container">
+                    <h3 data-text="queued-series">Queued Series</h3>
+                    <div id="queue-list" class="queue-list">
+                        <!-- Queue items will be populated here -->
+                    </div>
+                </div>
+            </section>
+
+            <!-- Series management section -->
+            <section class="series-section">
+                <div class="series-header">
+                    <h2 data-text="series-collection">Series Collection</h2>
+                    <div class="series-actions">
+                        <button id="select-all" class="btn btn-secondary">
+                            <i class="fas fa-check-double"></i>
+                            <span data-text="select-all">Select All</span>
+                        </button>
+                        <button id="download-selected" class="btn btn-success" disabled>
+                            <i class="fas fa-download"></i>
+                            <span data-text="download-selected">Download Selected</span>
+                        </button>
+                    </div>
+                </div>
+                
+                <!-- Series grid -->
+                <div id="series-grid" class="series-grid">
+                    <!-- Series cards will be populated here -->
+                </div>
+            </section>
+        </main>
+
+        <!-- Status panel -->
+        <div id="status-panel" class="status-panel hidden">
+            <div class="status-header">
+                <h3 id="status-title">Status</h3>
+                <button id="close-status" class="btn btn-icon">
+                    <i class="fas fa-times"></i>
+                </button>
+            </div>
+            <div class="status-content">
+                <div id="status-message" class="status-message"></div>
+                <div id="progress-container" class="progress-container hidden">
+                    <div class="progress-bar">
+                        <div id="progress-fill" class="progress-fill"></div>
+                    </div>
+                    <div id="progress-text" class="progress-text">0%</div>
+                </div>
+                <div id="download-controls" class="download-controls hidden">
+                    <button id="pause-download" class="btn btn-secondary btn-small">
+                        <i class="fas fa-pause"></i>
+                        <span data-text="pause">Pause</span>
+                    </button>
+                    <button id="resume-download" class="btn btn-primary btn-small hidden">
+                        <i class="fas fa-play"></i>
+                        <span data-text="resume">Resume</span>
+                    </button>
+                    <button id="cancel-download" class="btn btn-small" style="background-color: var(--color-error); color: white;">
+                        <i class="fas fa-stop"></i>
+                        <span data-text="cancel">Cancel</span>
+                    </button>
+                </div>
+            </div>
+        </div>
+
+        <!-- Configuration Modal -->
+        <div id="config-modal" class="modal hidden">
+            <div class="modal-overlay"></div>
+            <div class="modal-content">
+                <div class="modal-header">
+                    <h3 data-text="config-title">Configuration</h3>
+                    <button id="close-config" class="btn btn-icon">
+                        <i class="fas fa-times"></i>
+                    </button>
+                </div>
+                <div class="modal-body">
+                    <div class="config-item">
+                        <label data-text="anime-directory">Anime Directory:</label>
+                        <div id="anime-directory-display" class="config-value"></div>
+                    </div>
+                    <div class="config-item">
+                        <label data-text="series-count">Series Count:</label>
+                        <div id="series-count-display" class="config-value">0</div>
+                    </div>
+                    <div class="config-item">
+                        <label data-text="connection-status">Connection Status:</label>
+                        <div id="connection-status-display" class="config-value">
+                            <span class="status-indicator"></span>
+                            <span class="status-text">Disconnected</span>
+                        </div>
+                    </div>
+                </div>
+            </div>
+        </div>
+
+        <!-- Toast notifications -->
+        <div id="toast-container" class="toast-container"></div>
+    </div>
+
+    <!-- Loading overlay -->
+    <div id="loading-overlay" class="loading-overlay hidden">
+        <div class="loading-spinner">
+            <i class="fas fa-spinner fa-spin"></i>
+            <p>Loading...</p>
+        </div>
+    </div>
+
+    <!-- Scripts -->
+    <script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/4.0.1/socket.io.js"></script>
+    <script src="{{ url_for('static', filename='js/localization.js') }}"></script>
+    <script src="{{ url_for('static', filename='js/app.js') }}"></script>
+</body>
+</html>
\ No newline at end of file
diff --git a/src/server/test_app.py b/src/server/test_app.py
new file mode 100644
index 0000000..901607d
--- /dev/null
+++ b/src/server/test_app.py
@@ -0,0 +1,42 @@
+#!/usr/bin/env python3
+"""
+Test script to verify Flask app structure without initializing SeriesApp
+"""
+
+import sys
+import os
+
+# Test if we can import Flask modules
+try:
+    from flask import Flask
+    from flask_socketio import SocketIO
+    print("✅ Flask and SocketIO imports successful")
+except ImportError as e:
+    print(f"❌ Flask import failed: {e}")
+    sys.exit(1)
+
+# Test if we can import our modules
+try:
+    sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
+    from Serie import Serie
+    from SerieList import SerieList
+    print("✅ Core modules import successful")
+except ImportError as e:
+    print(f"❌ Core module import failed: {e}")
+    sys.exit(1)
+
+# Test Flask app creation
+try:
+    app = Flask(__name__)
+    app.config['SECRET_KEY'] = 'test-key'
+    socketio = SocketIO(app, cors_allowed_origins="*")
+    print("✅ Flask app creation successful")
+except Exception as e:
+    print(f"❌ Flask app creation failed: {e}")
+    sys.exit(1)
+
+print("🎉 All tests passed! Flask app structure is valid.")
+print("\nTo run the server:")
+print("1. Set ANIME_DIRECTORY environment variable to your anime directory")
+print("2. Run: python app.py")
+print("3. Open browser to http://localhost:5000")
\ No newline at end of file