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A bioluminescent deep-sea simulator that teaches CSS @keyframes, animation timing, and easing functions through environmental survival.

Find and fix accessibility (a11y) issues in broken HTML snippets.

A lightweight Git quest (Easy) to learn checkout basics by navigating a commit graph with `git log`, `git branch`, and `git checkout`.

Escape puzzle rooms by solving JavaScript closure, lexical scope, callback, and private state challenges.

Master CSS Grid through interactive layout challenges.

A heist caper where every vault lock is a Flexbox puzzle — write real CSS to slide gold bars onto their targets, judged live by the browser's own layout engine, scored on how few properties you use.

Interactive memory profiling and garbage collection diagnostic simulator for learning JavaScript memory management and leak prevention.

A heist-themed JavaScript quest where you orchestrate Promise chains and queueMicrotask calls to produce an exact execution order.

Master CSS selectors through interactive golf-style challenges by writing the shortest valid selector to match target elements.

Learn and practice SQL queries in the browser with an interactive SQLite WASM database across progressive levels.

A field excavation of version history; an interactive Git rebase simulator that turns commit history cleanup into an archaeological dig.

A fast-paced CLI speed run challenge where you execute common terminal commands against the clock.

A Git survival horror arcade game where stale branches spawn, rot, and threaten to consume main—merge, rebase, or delete them before decay reaches 100%.

A horror-themed terminal escape room that teaches real Git commands — staging, detached HEAD, conflict resolution, and force pushing — under a draining sanity meter.

Interactive web security quest game teaching Cross-Site Scripting (XSS) prevention, HTML sanitization, and Content Security Policy (CSP) headers.

A circular rhythm studio using the Euclidean algorithm across concentric glowing rings to create complex polyrhythms.

A dual-oscillator browser synthesizer featuring custom waveform drawing on frosted glass, dynamic ADSR envelopes, and lush reverb.

A skeuomorphic guitar neck to explore chord voicings and fingerings, featuring physical-modeling acoustic strumming via mouse swipes.

A real-time bridge between standard musical notation and a visual piano keyboard for interactive theory and harmony learning.

An 8x8 neon neumorphic performance grid synthesizer mapped to a Pentatonic scale with real-time audio and dynamic ripple animations.

A sleek neumorphic 808-style drum machine and step sequencer powered by the Web Audio API with real-time controls.

Master JavaScript closures by solving interactive puzzles across 10 levels covering scope, lexical bindings, private variables, and the module pattern.

A 10-level quiz with a retro terminal theme to test your command-line knowledge.

Learn CSS Grid through 6 interactive challenges.

Escape themed programming rooms by solving interactive puzzles covering HTML, CSS, JavaScript, Git, APIs, and JSON while unlocking new challenges.

A 10-level quiz with a retro terminal theme to test your Git command knowledge.

Guess the right status code for a scenario in this interactive quiz.

Test your understanding of JavaScript type coercion through interactive multiple-choice challenges.

Master Git branching through 8 interactive challenges covering create, list, switch, delete, merge, fast-forward, conflicts, and rebase.