:root{--primary: #6366f1;--primary-dark: #4f46e5;--primary-neo-dark: #2b24b1;--secondary: #10b981;--danger: #ef4444;--dark: #1e293b;--gray: #64748b;--light: #f8fafc;--white: #ffffff;--shadow: 0 4px 6px -1px rgba(0, 0, 0, .1), 0 2px 4px -2px rgba(0, 0, 0, .1);--shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, .1), 0 4px 6px -4px rgba(0, 0, 0, .1);--radius: 12px;--transition: all .3s ease}*{margin:0;padding:0;box-sizing:border-box}body{font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:radial-gradient(circle at 20% 20%,rgba(99,102,241,.16),transparent 24%),radial-gradient(circle at 85% 12%,rgba(16,185,129,.12),transparent 18%),linear-gradient(135deg,#020617,#111827);min-height:100vh;display:flex;align-items:center;justify-content:center;padding:24px;color:#e2e8f0}#root{width:100%;max-width:880px}.card{background:#fffffffa;border:1px solid rgba(148,163,184,.16);border-radius:var(--radius);box-shadow:0 35px 80px #0f172a2e;padding:40px;animation:slideUp .45s ease}@keyframes slideUp{0%{opacity:0;transform:translateY(30px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes scaleIn{0%{opacity:0;transform:scale(.9)}to{opacity:1;transform:scale(1)}}.start-screen{text-align:center}.logo-cont{width:80px;height:80px;background:linear-gradient(135deg,var(--primary),var(--primary-dark));border-radius:20px;display:flex;align-items:center;justify-content:center;margin:0 auto 24px;font-size:36px;color:#fff;animation:pulse 2s infinite}.logo{width:60px}@keyframes pulse{0%,to{transform:scale(1)}50%{transform:scale(1.05)}}.start-screen h1{font-size:28px;color:var(--dark);margin-bottom:12px}.start-screen p{color:var(--gray);margin-bottom:24px;font-size:16px}.hero{display:grid;gap:24px;margin-bottom:32px}.hero h2{color:var(--dark)}.hero-badge{display:inline-flex;align-items:center;justify-content:center;background:#6366f124;color:var(--primary);padding:10px 18px;border-radius:999px;font-weight:700;letter-spacing:.02em;width:fit-content}.hero-title{display:flex;align-items:center;gap:18px}.screen-header{display:flex;gap:18px;align-items:flex-start;margin-bottom:32px}.summary-grid,.stats-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-bottom:28px}.stat-card{background:var(--light);border-radius:var(--radius);padding:18px 20px;border:1px solid rgba(99,102,241,.12)}.stat-card strong{display:block;margin-top:8px;font-size:22px;color:var(--dark)}.stat-label{font-size:13px;color:var(--gray)}.screen-header .logo{width:76px;height:76px;margin:0}.level-screen{display:flex;flex-direction:column;gap:1rem}.meta-group{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.answered-pill{background:#6366f11f;color:var(--primary);padding:6px 12px;border-radius:999px;font-size:13px;font-weight:600}.difficulty-legend{display:flex;justify-content:center;gap:16px;margin-bottom:32px;font-size:14px;font-weight:500}.level-options{display:flex;flex-direction:column;gap:12px;margin-bottom:24px}.level-btn{background:var(--light);border:2px solid transparent;padding:20px;border-radius:var(--radius);cursor:pointer;transition:var(--transition);display:flex;flex-direction:column;align-items:center;gap:4px}.level-btn:hover{background:#e0e7ff;border-color:var(--primary)}.level-title{font-size:18px;font-weight:600;color:var(--dark)}.level-desc{font-size:14px;color:var(--gray)}.btn{background:var(--primary);color:#fff;border:none;padding:14px 32px;font-size:16px;font-weight:600;border-radius:var(--radius);cursor:pointer;transition:var(--transition);display:inline-flex;align-items:center;gap:8px}.btn:hover{background:var(--primary-dark);transform:translateY(-2px);box-shadow:var(--shadow)}.btn:active{transform:translateY(0)}.btn-secondary{background:var(--light);color:var(--dark)}.btn-secondary:hover{background:#e2e8f0}.progress-bar{width:100%;height:6px;background:#e2e8f0;border-radius:3px;margin-bottom:32px;overflow:hidden}.progress-fill{height:100%;background:linear-gradient(90deg,var(--primary),var(--primary-dark));border-radius:3px;transition:width .5s ease}.question-screen h2{font-size:20px;color:var(--dark);margin-bottom:4px}.category-text{font-size:13px;color:var(--gray);margin-bottom:20px}.question-meta{display:flex;justify-content:space-between;align-items:center;margin-bottom:24px;font-size:14px;color:var(--gray)}.question-number{background:#e0e7ff;color:var(--primary);padding:4px 12px;border-radius:12px;font-weight:500}.timer{display:flex;align-items:center;gap:6px;font-weight:600;font-size:15px;padding:4px 12px;border-radius:12px;background:#f1f5f9;transition:color .3s ease}.timer-icon{font-size:16px}.timer-value{min-width:32px;text-align:center}.difficulty-badge{color:#fff;padding:4px 12px;border-radius:12px;font-size:12px;font-weight:600}.options{display:flex;flex-direction:column;gap:12px;margin-bottom:32px}.option{background:var(--light);border:2px solid transparent;padding:16px 20px;border-radius:var(--radius);cursor:pointer;transition:var(--transition);display:flex;align-items:center;gap:12px;animation:scaleIn .3s ease;animation-fill-mode:both}.option:nth-child(1){animation-delay:.05s}.option:nth-child(2){animation-delay:.1s}.option:nth-child(3){animation-delay:.15s}.option:nth-child(4){animation-delay:.2s}.option:hover{background:#e0e7ff;border-color:var(--primary)}.option.selected{background:#eef2ff;border-color:var(--primary)}.option-icon{width:28px;height:28px;border-radius:50%;border:2px solid #cbd5e1;display:flex;align-items:center;justify-content:center;font-size:12px;color:var(--gray);transition:var(--transition);flex-shrink:0}.option.selected .option-icon{background:var(--primary);border-color:var(--primary);color:#fff}.option.correct{background:#dcfce7;border-color:var(--secondary)}.option.correct .option-icon{background:var(--secondary);border-color:var(--secondary);color:#fff}.option.incorrect{background:#fee2e2;border-color:var(--danger)}.option.incorrect .option-icon{background:var(--danger);border-color:var(--danger);color:#fff}.feedback{margin-top:16px;padding:16px;border-radius:var(--radius);animation:fadeIn .3s ease}.feedback.correct{background:#dcfce7;border:1px solid var(--secondary)}.feedback.incorrect{background:#fee2e2;border:1px solid var(--danger)}.feedback-icon{font-size:20px;margin-right:8px}.feedback-text{color:var(--dark);font-size:14px;font-weight:500}.navigation{display:flex;gap:12px;justify-content:flex-end}.nav-btn{padding:12px 24px;max-width:max-content;font-size:15px;background-color:var(--primary)}.nav-btn:hover{color:var(--light);background-color:var(--primary-neo-dark)}.result-screen{text-align:center}.result-icon{width:100px;height:100px;border-radius:50%;display:flex;align-items:center;justify-content:center;margin:0 auto 24px;font-size:48px}.result-icon.excellent{background:linear-gradient(135deg,#10b981,#059669)}.result-icon.good{background:linear-gradient(135deg,#f59e0b,#d97706)}.result-icon.needs-practice{background:linear-gradient(135deg,#ef4444,#dc2626)}.result-screen h1{font-size:28px;margin-bottom:8px}.result-message{color:var(--gray);margin-bottom:24px;font-size:16px}.score-display{background:var(--light);border-radius:var(--radius);padding:24px;margin-bottom:24px}.score-value{font-size:48px;font-weight:700;color:var(--dark);display:block}.stats-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin-top:20px;padding-top:16px;border-top:1px solid #e2e8f0}.stats-grid .stat{background:#fff;border-radius:16px;padding:16px}.score-label{color:var(--gray);font-size:14px;text-transform:uppercase;letter-spacing:1px}.stats{display:flex;justify-content:center;gap:32px;margin-top:16px;padding-top:16px;border-top:1px solid #e2e8f0}.stat{text-align:center}.stat-value{display:block;font-size:24px;font-weight:600;color:var(--dark)}.stat-label{font-size:12px;color:var(--gray)}.result-actions{display:flex;gap:12px;justify-content:center}@media (max-width: 480px){.card{padding:24px}.start-screen h1{font-size:24px}.question-text{font-size:16px}.result-actions{flex-direction:column}.difficulty-legend{flex-direction:column;gap:8px}}