Sudoku Mobile

A colorful, kid-friendly 9x9 Sudoku game built with HTML, CSS, and vanilla JavaScript. Three difficulty levels, countdown timer, and click-to-play number pad.

Live demo →  ·  View on GitHub →  ·  Get a quote →

▶ Open live demo — https://alfredang.github.io/sudoku/

About the project

A colorful, kid-friendly 9×9 Sudoku game built with plain HTML, CSS, and JavaScript. No frameworks, no dependencies — just open and play!

Tech stack

JavaScript   browser-game   css   game   github-pages   html   javascript   kids   puzzle   sudoku   vanilla-js

Key features

• 3 Difficulty Levels — Easy (15 min), Medium (10 min), Hard (5 min)
• Countdown Timer — Pulses red when under 30 seconds
• Click-to-Play — Tap cells and number buttons (no keyboard needed)
• Rule Validation — Highlights conflicts in red with friendly messages
• Win Detection — Celebration animation when you solve the puzzle
• Give Up — Reveals the full solution with color-coded answers
• Solution Reveal Colors:
• ⬛ Black — Original given numbers

Project details

Repository	sudoku
Live demo	https://alfredang.github.io/sudoku/
Primary language	JavaScript
Last update	13 Feb 2026

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