:root{--bg-deep: #0B0F19;--bg-surface: #121826;--bg-card: #182032;--bg-card-hover: #1E2942;--bg-input: #0F1422;--gradient-primary: linear-gradient(135deg, #8B5CF6 0%, #3B82F6 100%);--gradient-success: linear-gradient(135deg, #10B981 0%, #059669 100%);--gradient-error: linear-gradient(135deg, #EF4444 0%, #DC2626 100%);--gradient-text: linear-gradient(135deg, #FFFFFF 20%, #A5B4FC 100%);--primary: #3B82F6;--primary-soft: rgba(59, 130, 246, .1);--primary-border: rgba(59, 130, 246, .2);--accent: #8B5CF6;--accent-soft: rgba(139, 92, 246, .1);--success: #10B981;--success-soft: rgba(16, 185, 129, .1);--success-border: rgba(16, 185, 129, .3);--error: #EF4444;--error-soft: rgba(239, 68, 68, .1);--error-border: rgba(239, 68, 68, .3);--warning: #F59E0B;--warning-soft: rgba(245, 158, 11, .1);--text-white: #FFFFFF;--text-primary: #E2E8F0;--text-secondary: #94A3B8;--text-muted: #64748B;--border: rgba(255, 255, 255, .06);--border-hover: rgba(255, 255, 255, .12);--border-focus: rgba(139, 92, 246, .4);--radius-sm: 8px;--radius-md: 12px;--radius-lg: 16px;--radius-xl: 24px;--radius-full: 9999px;--transition: all .25s cubic-bezier(.4, 0, .2, 1);--font-sans: "Inter", system-ui, -apple-system, sans-serif;--font-display: "Outfit", sans-serif;--font-mono: "Fira Code", monospace;--shadow-sm: 0 2px 8px rgba(0, 0, 0, .2);--shadow-md: 0 8px 24px rgba(0, 0, 0, .3);--shadow-lg: 0 16px 48px rgba(0, 0, 0, .4)}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth}body{font-family:var(--font-sans);background-color:var(--bg-deep);color:var(--text-primary);line-height:1.6;min-height:100vh;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background-image:radial-gradient(ellipse 50% 30% at 20% 0%,rgba(139,92,246,.08),transparent 70%),radial-gradient(ellipse 40% 40% at 80% 90%,rgba(59,130,246,.06),transparent 70%);background-attachment:fixed}a{color:inherit;text-decoration:none}button,input,select,textarea{font-family:inherit;font-size:inherit;color:inherit}button{cursor:pointer;border:none;background:none}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:var(--bg-deep)}::-webkit-scrollbar-thumb{background:var(--border-hover);border-radius:4px}::-webkit-scrollbar-thumb:hover{background:var(--text-muted)}.container{width:100%;max-width:1200px;margin:0 auto;padding:0 24px}.navbar{position:sticky;top:0;z-index:100;height:72px;background:#121826cc;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border-bottom:1px solid var(--border);display:flex;align-items:center;transition:var(--transition)}.nav-inner{display:flex;align-items:center;justify-content:space-between;width:100%}.nav-logo{display:flex;align-items:center;gap:12px;font-family:var(--font-display);font-size:1.3rem;font-weight:800;letter-spacing:-.02em}.nav-logo span{font-weight:500;background:var(--gradient-primary);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}.nav-links{display:flex;align-items:center;gap:8px}.nav-link{padding:8px 16px;border-radius:var(--radius-sm);font-size:.9rem;font-weight:600;color:var(--text-secondary);transition:var(--transition)}.nav-link:hover,.nav-link.active{color:var(--text-white);background:var(--primary-soft)}.nav-user{display:flex;align-items:center;gap:16px}.user-email-badge{font-size:.8rem;color:var(--text-secondary);background:var(--bg-card);padding:4px 12px;border-radius:var(--radius-full);border:1px solid var(--border)}h1,h2,h3,h4,h5,h6{font-family:var(--font-display);color:var(--text-white);font-weight:700}.gradient-text{background:var(--gradient-text);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}.hero{padding:60px 0 40px;text-align:center}.hero-badge{display:inline-flex;align-items:center;gap:8px;padding:6px 16px;border-radius:var(--radius-full);background:var(--accent-soft);border:1px solid rgba(139,92,246,.2);color:#a78bfa;font-size:.8rem;font-weight:700;margin-bottom:24px}.hero h1{font-size:clamp(2rem,5vw,3.5rem);font-weight:900;line-height:1.15;margin-bottom:16px;letter-spacing:-.01em}.hero p{color:var(--text-secondary);font-size:1.1rem;max-width:600px;margin:0 auto}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:10px 20px;border-radius:var(--radius-sm);font-size:.9rem;font-weight:600;transition:var(--transition);text-align:center}.btn-primary{background:var(--gradient-primary);color:var(--text-white);box-shadow:0 4px 12px #8b5cf640}.btn-primary:hover{transform:translateY(-2px);box-shadow:0 6px 20px #8b5cf666}.btn-secondary{background:var(--bg-card);border:1px solid var(--border);color:var(--text-primary)}.btn-secondary:hover{background:var(--bg-card-hover);border-color:var(--border-hover)}.btn-success{background:var(--gradient-success);color:var(--text-white)}.btn-success:hover{transform:translateY(-2px);box-shadow:0 4px 12px #10b9814d}.btn-sm{padding:6px 12px;font-size:.8rem}.btn-block{width:100%}.category-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:24px;margin-bottom:48px}.mcq-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(340px,1fr));gap:20px;margin-bottom:60px}.card{background-color:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:28px;transition:var(--transition);position:relative;overflow:hidden}.card:hover{transform:translateY(-4px);border-color:var(--primary-border);box-shadow:var(--shadow-md),0 0 20px #3b82f60d}.card-icon-box{width:48px;height:48px;border-radius:var(--radius-md);background:var(--bg-input);display:flex;align-items:center;justify-content:center;color:var(--primary);margin-bottom:20px;border:1px solid var(--border)}.card-title{font-size:1.25rem;font-weight:700;margin-bottom:8px}.card-desc{font-size:.9rem;color:var(--text-secondary);margin-bottom:20px;min-height:44px}.card-footer{display:flex;align-items:center;justify-content:space-between;border-top:1px solid var(--border);padding-top:16px;font-size:.8rem;color:var(--text-muted)}.search-container{max-width:600px;margin:32px auto 48px;position:relative}.search-input-box{position:relative;display:flex;align-items:center}.search-icon{position:absolute;left:16px;color:var(--text-muted)}.search-input{width:100%;padding:14px 16px 14px 48px;background:var(--bg-surface);border:1px solid var(--border);border-radius:var(--radius-full);outline:none;transition:var(--transition);font-size:.95rem}.search-input:focus{border-color:var(--primary);box-shadow:0 0 0 4px var(--primary-soft);background:var(--bg-card)}.exam-header-card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:32px;margin-bottom:32px}.exam-meta{display:flex;gap:16px;margin-top:16px;flex-wrap:wrap}.exam-badge{font-size:.75rem;font-weight:600;padding:4px 12px;border-radius:var(--radius-full);background:var(--bg-input);border:1px solid var(--border);color:var(--text-secondary)}.exam-badge.active{background:var(--primary-soft);border-color:var(--primary-border);color:var(--primary)}.mcq-question-card{background:var(--bg-card);border:1px solid 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var(--border);color:var(--text-primary);text-align:left;transition:var(--transition);font-size:.95rem}.option-btn:hover{background:var(--bg-card-hover);border-color:var(--border-hover)}.option-btn.selected{border-color:var(--primary);background:var(--primary-soft);color:var(--text-white)}.option-btn.correct{border-color:var(--success);background:var(--success-soft);color:var(--success)}.option-btn.incorrect{border-color:var(--error);background:var(--error-soft);color:var(--error)}.option-prefix{width:28px;height:28px;border-radius:50%;background:#ffffff0a;display:flex;align-items:center;justify-content:center;font-size:.8rem;font-weight:700;margin-right:12px;flex-shrink:0;border:1px solid var(--border)}.option-btn.selected .option-prefix{background:var(--primary);border-color:var(--primary);color:#fff}.option-btn.correct .option-prefix{background:var(--success);border-color:var(--success);color:#fff}.option-btn.incorrect 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var(--success-border);color:var(--success);padding:12px;border-radius:var(--radius-sm);font-size:.85rem;margin-bottom:20px}.dashboard-title-row{display:flex;justify-content:space-between;align-items:center;margin-bottom:32px;flex-wrap:wrap;gap:16px}.history-table-box{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);overflow-x:auto}.history-table{width:100%;border-collapse:collapse;text-align:left}.history-table th,.history-table td{padding:16px 24px;border-bottom:1px solid var(--border)}.history-table th{font-family:var(--font-display);font-weight:700;text-transform:uppercase;font-size:.75rem;color:var(--text-secondary);background:#0000001a;letter-spacing:.05em}.history-table tr:last-child td{border-bottom:none}.score-badge{display:inline-flex;align-items:center;padding:4px 10px;border-radius:var(--radius-full);font-size:.8rem;font-weight:700}.score-badge.high{background:var(--success-soft);color:var(--success);border:1px solid var(--success-border)}.score-badge.low{background:var(--error-soft);color:var(--error);border:1px solid var(--error-border)}.footer{border-top:1px solid var(--border);padding:40px 0;margin-top:80px;text-align:center;color:var(--text-muted);font-size:.85rem}.hamburger{display:none}@media (max-width: 768px){.hamburger{display:block}.nav-links{display:none}.category-grid,.mcq-grid{grid-template-columns:1fr}.floating-inner{flex-direction:column;gap:12px;text-align:center}}.chart-bar{transition:all .2s ease}.chart-bar:hover{background:linear-gradient(to top,var(--primary-light),#c084fc)!important;box-shadow:0 0 12px #8b5cf666}.chart-bar:hover .chart-tooltip{opacity:1!important;bottom:115%!important}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.spin{animation:spin 1s linear infinite}