.quiz-card{position:relative;padding-top:.5rem}.progress-bar{height:6px;background:#e5e7eb;border-radius:999px;margin-bottom:1.25rem;overflow:hidden}.progress-fill{height:100%;background:linear-gradient(90deg,#667eea,#764ba2);border-radius:999px;transition:width .4s ease}.question-count{font-size:.85rem;color:#888;font-weight:500}.question-text{font-size:1.3rem;color:#1a1a2e;margin:.75rem 0 1.5rem;line-height:1.5}.options-list{list-style:none;display:flex;flex-direction:column;gap:.75rem}.option-btn{width:100%;display:flex;align-items:center;gap:.75rem;padding:.85rem 1rem;border:2px solid #e5e7eb;border-radius:.75rem;background:#fafafa;font-size:1rem;color:#2d2d2d;cursor:pointer;text-align:left;transition:border-color .15s,background .15s,transform .1s}.option-btn:hover:not(:disabled){border-color:#667eea;background:#f0f0ff;transform:translate(4px)}.option-btn:disabled{cursor:default}.option-btn.correct{border-color:#22c55e;background:#f0fdf4;color:#15803d;font-weight:600}.option-btn.wrong{border-color:#ef4444;background:#fef2f2;color:#b91c1c}.option-letter{display:inline-flex;align-items:center;justify-content:center;width:2rem;height:2rem;border-radius:50%;background:#e5e7eb;font-weight:700;font-size:.85rem;flex-shrink:0;color:#555}.option-btn.correct .option-letter{background:#22c55e;color:#fff}.option-btn.wrong .option-letter{background:#ef4444;color:#fff}.result-card{text-align:center}.result-card h2{font-size:1.75rem;color:#1a1a2e;margin-bottom:.25rem}.result-message{font-size:1.1rem;color:#555;margin-bottom:1.5rem}.score-circle{display:inline-flex;align-items:baseline;justify-content:center;gap:.25rem;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border-radius:50%;width:130px;height:130px;margin:0 auto .75rem}.score-number{font-size:3rem;font-weight:700}.score-divider{font-size:1.25rem;opacity:.8}.score-percentage{font-size:1rem;color:#888;margin-bottom:1.75rem}.stats-card{padding:30px;max-width:600px}.stats-table{margin-top:20px;border-collapse:collapse}.stats-header{display:grid;grid-template-columns:1fr 1fr 1fr 1fr;gap:10px;padding:15px;background:#f0f0f0;border-radius:4px;font-weight:700;margin-bottom:10px}.stats-row{display:grid;grid-template-columns:1fr 1fr 1fr 1fr;gap:10px;padding:15px;border-bottom:1px solid #eee}.stats-row:hover{background:#f9f9f9}.stat-col{text-align:center}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}body{font-family:Segoe UI,system-ui,sans-serif;background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);min-height:100vh;display:flex;align-items:center;justify-content:center}.app{width:100%;display:flex;justify-content:center;align-items:center;min-height:100vh;padding:1rem}.card{background:#fff;border-radius:1.25rem;padding:2rem;width:100%;max-width:560px;box-shadow:0 20px 60px #0003}.btn{display:inline-block;padding:.75rem 2rem;border:none;border-radius:.75rem;font-size:1rem;font-weight:600;cursor:pointer;transition:transform .1s,opacity .2s}.btn:active{transform:scale(.97)}.btn-primary{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;width:100%}.btn-primary:hover{opacity:.9}.start-card{text-align:center}.start-card h1{font-size:1.75rem;color:#2d2d2d;margin-bottom:.5rem}.start-card p{color:#666;margin-bottom:1.5rem}.card.start-card{max-width:560px}@media (min-width: 640px){.card.start-card{max-width:760px}}@media (min-width: 1024px){.card.start-card{max-width:1080px}}.category-header{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:.5rem;margin-bottom:.5rem}.category-header-actions{display:flex;flex-wrap:wrap;gap:.5rem}.category-grid{margin-top:20px;display:grid;gap:10px;grid-template-columns:1fr}@media (min-width: 500px){.category-grid{grid-template-columns:repeat(2,1fr)}}@media (min-width: 900px){.category-grid{grid-template-columns:repeat(3,1fr)}}@media (min-width: 1200px){.category-grid{grid-template-columns:repeat(4,1fr)}}