*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{font-size:16px;-webkit-font-smoothing:antialiased}
body{font-family:'Inter',-apple-system,system-ui,sans-serif;background:#0A0A1A;color:#E2E8F0;min-height:100vh;overflow:hidden}
#app{width:100vw;height:100vh;position:relative}
.screen{position:absolute;inset:0;display:none;flex-direction:column;align-items:center;justify-content:center;padding:20px}
.screen.active{display:flex}

/* Menu */
.title{font-size:2.2rem;font-weight:700;text-align:center;background:linear-gradient(135deg,#8B5CF6,#06B6D4);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:4px}
.subtitle{font-size:.9rem;color:#64748B;margin-bottom:24px}
.menu-options{display:flex;flex-direction:column;gap:10px;width:260px}
.btn-menu{padding:12px 24px;border:1px solid rgba(139,92,246,0.2);border-radius:10px;background:rgba(139,92,246,0.08);color:#C4B5FD;font-family:inherit;font-size:.9rem;font-weight:600;cursor:pointer;transition:all .25s ease}
.btn-menu:hover{background:rgba(139,92,246,0.2);border-color:rgba(139,92,246,0.4);transform:translateY(-2px);box-shadow:0 4px 16px rgba(139,92,246,0.15)}
.btn-menu.secondary{background:rgba(100,116,139,0.1);color:#94A3B8;border-color:rgba(100,116,139,0.2)}
.high-score-mini{margin-top:20px;font-size:.72rem;color:#64748B;font-family:'JetBrains Mono',monospace}

/* HUD */
.hud{display:flex;gap:16px;width:100%;max-width:800px;padding:12px 16px;justify-content:space-between;align-items:center}
.hud-item{display:flex;flex-direction:column;align-items:center;gap:2px}
.hud-label{font-size:.6rem;text-transform:uppercase;color:#64748B;letter-spacing:.06em}
.hud-value{font-family:'JetBrains Mono',monospace;font-weight:700;font-size:1.1rem;color:#C4B5FD}
.algo-name{font-size:.85rem;font-weight:700;color:#06B6D4}

/* Canvas */
canvas{display:block;width:100%;max-width:800px;border-radius:10px;border:1px solid rgba(139,92,246,0.12);margin:8px 0}

/* Question */
.question-panel{width:100%;max-width:800px;padding:12px 16px;text-align:center}
.question-text{font-size:.92rem;color:#C4B5FD;margin-bottom:10px;font-weight:600}
.answer-btns{display:flex;gap:8px;justify-content:center;flex-wrap:wrap}
.answer-btn{padding:8px 20px;border:1px solid rgba(139,92,246,0.2);border-radius:8px;background:rgba(139,92,246,0.06);color:#E2E8F0;font-family:'JetBrains Mono',monospace;font-size:.85rem;cursor:pointer;transition:all .2s ease;min-width:60px}
.answer-btn:hover{background:rgba(139,92,246,0.15);border-color:#8B5CF6;transform:scale(1.05)}
.answer-btn.correct{background:rgba(16,185,129,0.2);border-color:#10B981;color:#34D399}
.answer-btn.wrong{background:rgba(239,68,68,0.2);border-color:#EF4444;color:#EF4444}

/* Feedback */
.feedback{font-size:1.6rem;font-weight:700;height:36px;line-height:36px;transition:all .3s ease}
.feedback.correct{color:#10B981}
.feedback.wrong{color:#EF4444}

.explanation{font-size:.78rem;color:#94A3B8;max-width:700px;text-align:center;min-height:20px;padding:0 16px}

/* Game Over */
.over-title{font-size:1.8rem;color:#C4B5FD;margin-bottom:8px}
.final-score{font-family:'JetBrains Mono',monospace;font-size:2.4rem;font-weight:700;color:#06B6D4;margin-bottom:4px}
.final-stats{font-size:.78rem;color:#64748B;margin-bottom:20px;font-family:'JetBrains Mono',monospace}
.hs-title{color:#F59E0B;font-size:.9rem;margin:20px 0 8px}
.hs-list{font-family:'JetBrains Mono',monospace;font-size:.72rem;color:#94A3B8;line-height:1.8}

/* Shake */
@keyframes shake{0%,100%{transform:translateX(0)}25%{transform:translateX(-4px)}50%{transform:translateX(4px)}75%{transform:translateX(-2px)}}
.shake{animation:shake .3s ease}

/* Floating score */
.float-score{position:fixed;font-family:'JetBrains Mono',monospace;font-weight:700;font-size:1.1rem;pointer-events:none;z-index:100;animation:floatUp .8s ease-out forwards}
@keyframes floatUp{0%{opacity:1;transform:translateY(0)}100%{opacity:0;transform:translateY(-60px)}}

@media(max-width:640px){.title{font-size:1.5rem}.hud{flex-wrap:wrap;gap:8px}canvas{height:auto;max-height:260px}}