CSS

Build an immersive 3D space exploration game using Three.js and JavaScript. Create a vast universe with procedurally generated planets, stars, and nebulae. Implement realistic spacecraft controls with Newtonian physics. Add detailed planet surfaces with terrain generation and atmospheric effects. Create space stations and outposts for trading and missions. Implement resource collection and cargo management systems. Add alien species with unique behaviors and interactions. Create wormhole travel effects between star systems. Include detailed ship customization and upgrade system. Implement mining and combat mechanics with weapon effects. Add mission system with story elements and objectives.

Create an interactive drawing application using HTML5 Canvas, CSS3, and JavaScript. Build a clean interface with intuitive tool selection. Implement multiple drawing tools including brush, pencil, shapes, text, and eraser. Add color selection with recent colors, color picker, and palettes. Include layer support with opacity and blend mode options. Implement undo/redo functionality with history states. Add image import and export in multiple formats (PNG, JPG, SVG). Support canvas resizing and rotation. Implement zoom and pan navigation. Add selection tools with move, resize, and transform capabilities. Include keyboard shortcuts for common actions.

Create a web-based PDF viewer using HTML5, CSS3, JavaScript and PDF.js. Build a clean interface with intuitive navigation controls. Implement page navigation with thumbnails and outline view. Add text search with result highlighting. Include zoom and fit-to-width/height controls. Implement text selection and copying. Add annotation tools including highlights, notes, and drawing. Support document rotation and presentation mode. Include print functionality with options. Create a responsive design that works on all devices. Add document properties and metadata display.

Build a comprehensive health metrics calculator with HTML5, CSS3 and JavaScript based on medical standards. Create a clean, accessible interface with step-by-step input forms. Implement accurate BMI calculation with visual classification scale and health risk assessment. Add body fat percentage calculator using multiple methods (Navy, Jackson-Pollock, BIA simulation). Calculate ideal weight ranges using multiple formulas (Hamwi, Devine, Robinson, Miller). Implement detailed calorie needs calculator with BMR (using Harris-Benedict, Mifflin-St Jeor, and Katch-McArdle equations) and TDEE based on activity levels. Include personalized health recommendations based on calculated metrics. Support both metric and imperial units with seamless conversion. Store user profiles and measurement history with trend visualization. Generate interactive progress charts showing changes over time. Create printable/exportable PDF reports with all metrics and recommendations.

Develop a comprehensive currency converter using HTML5, CSS3, JavaScript and a reliable Exchange Rate API. Create a clean, intuitive interface with prominent input fields and currency selectors. Implement real-time exchange rates with timestamp indicators showing data freshness. Support 170+ global currencies including crypto with appropriate symbols and formatting. Maintain a conversion history log with timestamps and rate information. Allow users to bookmark favorite currency pairs for quick access. Generate interactive historical rate charts with customizable date ranges. Implement offline functionality using cached exchange rates with clear staleness indicators. Add a built-in calculator for complex conversions and arithmetic operations. Create rate alerts for target exchange rates with optional notifications. Include side-by-side comparison of different provider rates when available. Support printing and exporting conversion results in multiple formats (PDF, CSV, JSON).

Develop a web-based music player using HTML5, CSS3, and JavaScript with the Web Audio API. Create a modern interface with album art display and visualizations. Implement playlist management with drag-and-drop reordering. Add audio controls including play/pause, skip, seek, volume, and playback speed. Include shuffle and repeat modes with visual indicators. Support multiple audio formats with fallbacks. Implement a 10-band equalizer with presets. Add metadata extraction and display from audio files. Create a responsive design that works on all devices. Include keyboard shortcuts for playback control. Support background playback with media session API integration.

Build an interactive typing speed test using HTML5, CSS3, and JavaScript. Create a clean interface with text display and input area. Implement WPM and accuracy calculation in real-time. Add difficulty levels with appropriate text selection. Include error highlighting and correction tracking. Implement test history with performance graphs. Add custom test creation with text import. Include virtual keyboard display showing keypresses. Support multiple languages and keyboard layouts. Create a responsive design for all devices. Add competition mode with leaderboards.

Create a habit tracking application using HTML5, CSS3, and JavaScript. Build a clean interface showing daily, weekly, and monthly views. Implement habit creation with frequency, reminders, and goals. Add streak tracking with visual indicators and milestone celebrations. Include detailed statistics and progress graphs. Support habit categories and tags for organization. Implement calendar integration for scheduling. Add data visualization showing patterns and trends. Create a responsive design for all devices. Include data export and backup functionality. Add gamification elements with achievements and rewards.

Create a client-side file encryption tool using HTML5, CSS3, and JavaScript with the Web Crypto API. Build a drag-and-drop interface for file selection with progress indicators. Implement AES-256-GCM encryption with secure key derivation from passwords (PBKDF2). Add support for encrypting multiple files simultaneously with batch processing. Include password strength enforcement with entropy calculation. Generate downloadable encrypted files with custom file extension. Create a decryption interface with password verification. Implement secure memory handling with automatic clearing of sensitive data. Add detailed logs of encryption operations without storing sensitive information. Include export/import of encryption keys with proper security warnings. Support for large files using streaming encryption and chunked processing.

Develop a first-person shooter game using Three.js and JavaScript. Create detailed weapon models with realistic animations and effects. Implement precise hit detection and damage systems. Design multiple game levels with various environments and objectives. Add AI enemies with pathfinding and combat behaviors. Create particle effects for muzzle flashes, impacts, and explosions. Implement multiplayer mode with team-based objectives. Include weapon pickup and inventory system. Add sound effects for weapons, footsteps, and environment. Create detailed scoring and statistics tracking. Implement replay system for kill cams and match highlights.

Develop a comprehensive interactive quiz application with HTML5, CSS3 and JavaScript. Create an engaging UI with smooth transitions between questions. Support multiple question types including multiple choice, true/false, matching, and short answer with automatic grading. Implement configurable timers per question with visual countdown. Add detailed score tracking with points based on difficulty and response time. Show a dynamic progress bar indicating completion percentage. Include a review mode to see correct/incorrect answers with explanations after quiz completion. Implement a persistent leaderboard using localStorage. Organize questions into categories with custom icons and descriptions. Support multiple difficulty levels affecting scoring and time limits. Generate a detailed results summary with performance analytics and improvement suggestions. Add social sharing functionality for results with customizable messages.

Create an exciting 3D racing game using Three.js and JavaScript. Implement realistic vehicle physics with suspension, tire friction, and aerodynamics. Create detailed car models with customizable paint and upgrades. Design multiple race tracks with varying terrain and obstacles. Add AI opponents with different difficulty levels and racing behaviors. Implement a split-screen multiplayer mode for local racing. Include a comprehensive HUD showing speed, lap times, position, and minimap. Create particle effects for tire smoke, engine effects, and weather. Add dynamic day/night cycle with realistic lighting. Implement race modes including time trial, championship, and elimination. Include replay system with multiple camera angles.