:root{--bg: #f4f5fb;--surface: #ffffff;--fg: #1b1b2f;--muted: #6b7280;--border: #e5e7eb;--primary: #4f46e5;--primary-fg: #ffffff;--ok: #16a34a;--ok-bg: #dcfce7;--bad: #dc2626;--bad-bg: #fee2e2;--radius: 14px;--gap: 16px;--shadow: 0 6px 24px rgba(20, 20, 50, .08);--maxw: 640px}[data-theme=dark]{--bg: #0f1020;--surface: #1a1b34;--fg: #ececf5;--muted: #9aa0b4;--border: #2a2c4a;--primary: #818cf8;--primary-fg: #0f1020;--ok: #4ade80;--ok-bg: #14321f;--bad: #f87171;--bad-bg: #3a1414;--shadow: 0 6px 24px rgba(0, 0, 0, .4)}*{box-sizing:border-box}body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;background:var(--bg);color:var(--fg);line-height:1.5}.app-header{display:flex;align-items:center;justify-content:space-between;padding:12px 16px;max-width:var(--maxw);margin:0 auto}.app-header__title{font-weight:700;letter-spacing:.02em}.theme-toggle{border:1px solid var(--border);background:var(--surface);border-radius:999px;width:40px;height:40px;cursor:pointer;font-size:18px}.app{max-width:var(--maxw);margin:0 auto;padding:8px 16px 48px}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:24px;display:flex;flex-direction:column;gap:var(--gap)}h1,h2{margin:0}.muted{color:var(--muted)}.greeting{color:var(--muted);margin:0}.error{color:var(--bad);margin:0}.form{display:flex;flex-direction:column;gap:12px}.label{font-weight:600}.input{padding:12px 14px;border:1px solid var(--border);border-radius:10px;font-size:16px;background:var(--bg);color:var(--fg)}.input:focus-visible{outline:3px solid var(--primary);outline-offset:1px}.btn{font:inherit;padding:12px 16px;border-radius:10px;border:1px solid var(--border);background:var(--surface);color:var(--fg);cursor:pointer;transition:transform .05s ease,filter .15s ease}.btn:hover{filter:brightness(.98)}.btn:active{transform:translateY(1px)}.btn:focus-visible{outline:3px solid var(--primary);outline-offset:2px}.btn:disabled{opacity:.5;cursor:not-allowed}.btn--primary{background:var(--primary);color:var(--primary-fg);border-color:var(--primary)}.btn--ghost{background:transparent}.btn--card{display:flex;justify-content:space-between;align-items:center;gap:8px;text-align:left;padding:16px;font-weight:600}.grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}.list{display:flex;flex-direction:column;gap:10px}.quiz__top{display:flex;justify-content:space-between;align-items:center}.timer{font-variant-numeric:tabular-nums;font-weight:700}.progress{height:8px;background:var(--border);border-radius:999px;overflow:hidden}.progress__bar{height:100%;background:var(--primary);transition:width .2s ease}.quiz__question{font-size:1.15rem}.options{border:0;padding:0;margin:0;display:flex;flex-direction:column;gap:10px}.option{display:flex;align-items:center;gap:12px;padding:14px;border:1px solid var(--border);border-radius:10px;cursor:pointer}.option:focus-within{outline:3px solid var(--primary);outline-offset:1px}.option--selected{border-color:var(--primary);background:color-mix(in srgb,var(--primary) 10%,transparent)}.option input{width:20px;height:20px}.quiz__nav{display:flex;justify-content:space-between;gap:12px}.quiz__nav .btn{flex:1}.results__score{font-size:2rem;font-weight:800;margin:0}.results__grade{margin:0;font-size:1.1rem}.summary{list-style:none;padding:0;margin:0;display:flex;flex-direction:column;gap:12px}.summary__item{border:1px solid var(--border);border-left-width:5px;border-radius:10px;padding:12px 14px}.summary__item--ok{border-left-color:var(--ok);background:var(--ok-bg)}.summary__item--bad{border-left-color:var(--bad);background:var(--bad-bg)}.summary__q{font-weight:600;margin:0 0 6px}.summary__mark{margin:0 0 6px;font-weight:700}.summary__line{margin:2px 0}.results__actions{display:flex;flex-direction:column;gap:10px}@media (min-width: 560px){.results__actions{flex-direction:row}.results__actions .btn{flex:1}}