:root{--bg: #fafafa;--bg-raised: #ffffff;--bg-card: #ffffff;--fg: #0b1411;--fg-muted: #4b5b56;--fg-subtle: #8a9893;--border: #d8e3df;--accent: #14b8a6;--accent-hover: #0d9488;--accent-bg: #ccfbf1;--accent-fg: #0b3a36;--on-accent: #ffffff;--correct: #16a34a;--wrong: #dc2626;--warn: #d97706;--tap: 44px;--radius: 12px;--font-display: "Cal Sans", system-ui, sans-serif;--font-body: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;--font-mono: "JetBrains Mono", ui-monospace, monospace;--shadow-sm: 0 1px 2px 0 rgba(15, 23, 42, .06);--shadow-md: 0 4px 12px -2px rgba(15, 23, 42, .1);--shadow-lg: 0 12px 28px -8px rgba(15, 23, 42, .18);color-scheme:light}[data-theme=dark]{--bg: #07100e;--bg-raised: #0e1b18;--bg-card: #112623;--fg: #ecfdf5;--fg-muted: #99b6ad;--fg-subtle: #648078;--border: #1f3530;--accent: #2dd4bf;--accent-hover: #14b8a6;--accent-bg: #134e4a;--accent-fg: #ecfdf5;--on-accent: #07100e;--correct: #22c55e;--wrong: #ef4444;--warn: #f59e0b;--shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, .32);--shadow-md: 0 4px 14px -2px rgba(0, 0, 0, .42);--shadow-lg: 0 14px 32px -10px rgba(0, 0, 0, .55);color-scheme:dark}*,*:before,*:after{box-sizing:border-box}html,body{margin:0;padding:0;min-height:100dvh;background:var(--bg);color:var(--fg);font-family:var(--font-body);-webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent}body{padding-top:env(safe-area-inset-top);padding-bottom:env(safe-area-inset-bottom)}a{color:var(--accent);text-decoration:none;font-weight:500}a:hover{color:var(--accent-hover);text-decoration:underline}button{font-family:inherit;cursor:pointer;touch-action:manipulation}input,button,select,textarea{font-family:inherit;font-size:16px;color:inherit}input,textarea,select{background:var(--bg-raised);border:1px solid var(--border);border-radius:var(--radius);padding:.625rem .875rem;min-height:var(--tap);width:100%;transition:border-color .12s ease,box-shadow .12s ease}input:focus,textarea:focus,select:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-bg)}::placeholder{color:var(--fg-subtle);opacity:1}h1,h2,h3,h4{font-family:var(--font-display);font-weight:700;letter-spacing:-.01em;margin:0 0 .75rem}main,.page{max-width:720px;margin:0 auto;padding:1rem}@media (min-width: 768px){main,.page{padding:2rem 1.5rem}}