SumDoku | HTML5 Game

SumDoku takes the logic puzzle you already know and adds one new rule: every row and column must not only avoid repeating numbers — it must also add up to the exact same total. Simple to learn, satisfying to master, and built as a single self-contained HTML5 file with zero build tools and zero dependencies.

✨ Key Features

• 3 difficulty levels — Easy (4×4), Medium (5×5), Hard (6×6)
• Separate screens — Start Menu, How to Play, Settings, and Game, each with its own clean layout
• In-game pause menu — Resume, Restart Level, Sound toggle, Home
• Hint system — 3 free hints per round reveal hidden row/column sums, plus a rewarded-ad flow to earn more (simulated ad included, real ad SDK integration documented in one line)
• Web Audio sound effects — every tap, placement, mistake, and win is a synthesized tone; no audio files to load
• Win celebration — confetti animation and an animated win modal
• One-tap social sharing — native mobile share sheet, X/Twitter, WhatsApp, Facebook, and copy-to-clipboard
• Fully responsive — mobile-first layout that scales cleanly from small phones to desktop
• Bold neobrutalist visual style — thick borders, offset shadows, bright accent colors, easy to re-theme via CSS variables
• Single HTML5 file — drop it on any host, wrap it in Cordova/Capacitor, or embed it anywhere

Built For Developers

• Clean, commented vanilla JavaScript — no framework, no build step
• Full documentation included: customizing colors, fonts, difficulty curve, hints/ads, sounds, and sharing text
• One clearly marked function for plugging in a real rewarded-ad SDK (AdMob, Unity Ads, IronSource, etc.)

Compatibility

Chrome, Firefox, Safari, Edge, Opera, and their mobile equivalents (iOS Safari, Chrome for Android, Samsung Internet). Built with HTML5, CSS3, and ES6 JavaScript.