:root{--bg: #0f172a;--bg-accent: #1e293b;--card: #ffffff;--text: #0f172a;--muted: #64748b;--primary: #6366f1;--primary-dark: #4f46e5;--correct: #16a34a;--wrong: #dc2626;--border: #e2e8f0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif}*{box-sizing:border-box}body{margin:0;min-height:100vh;background:radial-gradient(1200px 600px at 50% -10%,#312e81 0%,var(--bg) 55%);color:var(--text);display:flex;align-items:center;justify-content:center}.app{width:100%;max-width:640px;padding:24px;display:flex;flex-direction:column;gap:16px}.card{background:var(--card);border-radius:20px;padding:32px;box-shadow:0 24px 60px #00000059}.header{display:flex;align-items:center;gap:12px;margin-bottom:20px}.brand{display:flex;align-items:center;gap:12px;padding:0;border:none;background:transparent;cursor:pointer;color:inherit}.header h1{margin:0;font-size:1.6rem}.logo{font-size:2rem}.section-title{margin:0 0 6px;font-size:1.25rem}.row{display:flex;gap:12px;align-items:flex-start}.row.between{justify-content:space-between;align-items:flex-start}.grow{flex:1}.field{display:flex;flex-direction:column;gap:6px;font-weight:600;font-size:.95rem}.field input,.field textarea{font:inherit;font-weight:400;padding:12px 14px;border:2px solid var(--border);border-radius:12px;resize:vertical}.field input:focus,.field textarea:focus{outline:none;border-color:var(--primary)}.quiz-list{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:12px}.quiz-row{display:flex;justify-content:space-between;gap:12px;align-items:center;padding:14px 16px;border:2px solid var(--border);border-radius:12px}.quiz-meta{display:flex;flex-direction:column;gap:4px}.quiz-actions{display:flex;gap:8px;flex-shrink:0}.empty{margin:0;padding:16px;border:2px dashed var(--border);border-radius:12px;color:var(--muted)}.inline-error{margin:0 0 12px}.tight{margin:0}.btn.danger{border-color:#fecaca;color:var(--wrong)}.btn.danger:hover:not(:disabled){border-color:var(--wrong);background:#fef2f2}.btn.linkish{border:none;padding:4px 8px;color:var(--muted);font-weight:600}.btn.linkish:hover:not(:disabled){color:var(--primary);border:none}@media(max-width:560px){.row.between,.quiz-row{flex-direction:column;align-items:stretch}.quiz-actions{width:100%}.quiz-actions .btn{flex:1}}.stack{display:flex;flex-direction:column;gap:20px}.lead{font-size:1.05rem;line-height:1.5;margin:0}.muted{color:var(--muted);margin:0}.error{color:var(--wrong);font-weight:600}.prompt{font-size:1.3rem;margin:0}.choices{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:12px}.choice{width:100%;text-align:left;padding:14px 16px;border:2px solid var(--border);border-radius:12px;background:#fff;font-size:1rem;cursor:pointer;display:flex;align-items:center;gap:12px;transition:border-color .15s,background .15s,transform .05s}.choice:hover{border-color:var(--primary)}.choice:active{transform:scale(.99)}.choice.selected{border-color:var(--primary);background:#eef2ff}.choice-marker{display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;border-radius:8px;background:var(--bg-accent);color:#fff;font-weight:700;flex-shrink:0}.choice.selected .choice-marker{background:var(--primary)}.btn{padding:12px 20px;border-radius:12px;border:2px solid var(--border);background:#fff;font-size:1rem;font-weight:600;cursor:pointer;transition:background .15s,border-color .15s,opacity .15s}.btn:hover:not(:disabled){border-color:var(--primary)}.btn:disabled{opacity:.5;cursor:not-allowed}.btn.primary{background:var(--primary);border-color:var(--primary);color:#fff}.btn.primary:hover:not(:disabled){background:var(--primary-dark);border-color:var(--primary-dark)}.nav{display:flex;justify-content:space-between;gap:12px}.progress{width:100%;height:8px;background:var(--border);border-radius:999px;overflow:hidden}.progress-bar{height:100%;background:var(--primary);transition:width .25s ease}.score{display:flex;flex-direction:column;align-items:center;gap:12px}.score-circle{width:120px;height:120px;border-radius:50%;background:conic-gradient(var(--primary) var(--pct, 0),var(--border) 0);display:flex;align-items:center;justify-content:center;background:#eef2ff;border:4px solid var(--primary)}.score-pct{font-size:2rem;font-weight:800;color:var(--primary-dark)}.review{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:12px}.review li{border:2px solid var(--border);border-radius:12px;padding:14px 16px}.review li.correct{border-color:var(--correct);background:#f0fdf4}.review li.wrong{border-color:var(--wrong);background:#fef2f2}.review-prompt{font-weight:700;display:flex;gap:8px;align-items:flex-start}.review-mark{font-weight:800}.review li.correct .review-mark{color:var(--correct)}.review li.wrong .review-mark{color:var(--wrong)}.review-detail{margin-top:6px;font-size:.95rem}.your-answer{color:var(--wrong)}.explanation{margin-top:6px;font-size:.9rem;color:var(--muted)}.footnote{text-align:center;color:#fff9;font-size:.85rem}