:root{--bg:#f5f7fb;--card:#fff;--text:#182235;--muted:#65708a;--line:#e4e8f2;--accent:#355cff;--accent-soft:#e9edff;--success:#178b57;--success-soft:#e9f7ef;--danger:#c73636;--danger-soft:#fdecec;--shadow:0 24px 70px #1822351f;--radius:28px}*{box-sizing:border-box}body{background:radial-gradient(circle at top left, #355cff24, transparent 32rem), radial-gradient(circle at bottom right, #178b571f, transparent 28rem), var(--bg);min-height:100vh;color:var(--text);margin:0;font-family:Inter,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}button{font:inherit}.app{place-items:center;width:min(980px,94vw);min-height:100vh;margin:0 auto;padding:32px 0;display:grid}.screen{width:100%;animation:.22s ease-out fadeIn;display:none}.screen.active{display:block}.hero-card,.quiz-card,.result-card{border-radius:var(--radius);box-shadow:var(--shadow);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);background:#ffffffe0;border:1px solid #e4e8f2e6}.hero-card{text-align:center;padding:clamp(28px,5vw,56px)}.badge,.eyebrow{background:var(--accent-soft);width:fit-content;color:var(--accent);letter-spacing:.04em;text-transform:uppercase;border-radius:999px;align-items:center;gap:8px;padding:8px 12px;font-size:.78rem;font-weight:800;display:inline-flex}h1,h2,h3,p{margin-top:0}h1{max-width:780px;margin:24px auto 18px;font-size:clamp(2.3rem,7vw,4.8rem);line-height:.96}.hero-card p,.result-card p{max-width:680px;color:var(--muted);margin:0 auto 28px;font-size:1.08rem;line-height:1.65}.topics-preview{grid-template-columns:repeat(4,1fr);gap:14px;margin:34px 0;display:grid}.topics-preview div{text-align:left;border:1px solid var(--line);background:#f8faff;border-radius:22px;flex-direction:column;justify-content:space-between;min-height:112px;padding:18px;display:flex}.topics-preview strong{color:var(--accent);font-size:.94rem}.topics-preview span{font-weight:800;line-height:1.25}.primary-btn,.secondary-btn{cursor:pointer;border:0;border-radius:18px;padding:15px 22px;font-weight:850;transition:transform .16s,box-shadow .16s,background .16s}.primary-btn{background:var(--accent);color:#fff;box-shadow:0 14px 26px #355cff38}.secondary-btn{color:var(--text);background:#eef2f8}.primary-btn:hover,.secondary-btn:hover{transform:translateY(-2px)}.quiz-card{padding:clamp(22px,4vw,42px)}.quiz-header{justify-content:space-between;align-items:flex-start;gap:18px;margin-bottom:28px;display:flex}.quiz-header h2{margin:14px 0 0;font-size:clamp(1.5rem,4vw,2.5rem);line-height:1.1}.score-pill{border:1px solid var(--line);color:var(--muted);background:#f8faff;border-radius:999px;flex:none;padding:12px 16px}.score-pill strong{color:var(--text)}.progress-area{margin-bottom:28px}.progress-info{color:var(--muted);justify-content:space-between;margin-bottom:10px;font-size:.95rem;display:flex}.progress-bar{background:#e8ecf6;border-radius:999px;height:12px;overflow:hidden}#progress-fill{border-radius:inherit;background:var(--accent);width:0%;height:100%;transition:width .24s}.question-area{border:1px solid var(--line);background:#fbfcff;border-radius:24px;padding:clamp(18px,3vw,28px)}.question-area h3{margin-bottom:22px;font-size:clamp(1.25rem,3vw,1.85rem);line-height:1.25}.options-grid{grid-template-columns:repeat(2,1fr);gap:14px;display:grid}.option-btn{border:1px solid var(--line);width:100%;min-height:84px;color:var(--text);text-align:left;cursor:pointer;background:#fff;border-radius:20px;padding:18px;transition:transform .15s,border-color .15s,background .15s}.option-btn:hover:not(:disabled){background:#f8faff;border-color:#355cff73;transform:translateY(-2px)}.option-btn:disabled{cursor:not-allowed}.option-prefix{background:var(--accent-soft);width:30px;height:30px;color:var(--accent);border-radius:10px;place-items:center;margin-right:10px;font-weight:900;display:inline-grid}.option-btn.correct{background:var(--success-soft);border-color:#178b5773}.option-btn.correct .option-prefix{background:var(--success);color:#fff}.option-btn.wrong{background:var(--danger-soft);border-color:#c736366b}.option-btn.wrong .option-prefix{background:var(--danger);color:#fff}.feedback{border-radius:20px;margin-top:18px;padding:16px 18px;font-weight:650;line-height:1.55}.feedback.success{background:var(--success-soft);color:var(--success)}.feedback.danger{background:var(--danger-soft);color:var(--danger)}.quiz-footer{justify-content:flex-end;margin-top:22px;display:flex}.hidden{display:none!important}.result-card{text-align:center;padding:clamp(26px,5vw,48px)}.result-card.small{max-width:680px;margin:0 auto}.result-card h2{margin:18px 0 12px;font-size:clamp(2rem,5vw,3.2rem)}.final-message{margin-bottom:18px!important}.final-score{border:1px solid var(--line);background:#f8faff;border-radius:26px;width:min(420px,100%);margin:20px auto 28px;padding:28px}.final-score span{letter-spacing:-.05em;font-size:clamp(2.5rem,8vw,4.8rem);font-weight:950;display:block}.final-score small{color:var(--muted);font-size:1.1rem;font-weight:850}.topic-breakdown{grid-template-columns:repeat(4,1fr);gap:12px;margin:26px 0 30px;display:grid}.topic-result-item{border:1px solid var(--line);text-align:left;background:#fbfcff;border-radius:18px;padding:16px}.topic-result-item strong{margin-bottom:8px;display:block}.topic-result-item span{color:var(--muted);font-weight:800}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}@media (width<=760px){.topics-preview,.topic-breakdown{grid-template-columns:1fr 1fr}.quiz-header{flex-direction:column}.score-pill{text-align:center;width:100%}.options-grid{grid-template-columns:1fr}}@media (width<=460px){.topics-preview,.topic-breakdown{grid-template-columns:1fr}.hero-card,.quiz-card,.result-card{border-radius:22px}.primary-btn,.secondary-btn{width:100%}}