:root{--bg-primary: #0a0e1a;--bg-secondary: #111827;--bg-card: rgba(17, 24, 39, .7);--bg-glass: rgba(255, 255, 255, .05);--border-glass: rgba(255, 255, 255, .1);--text-primary: #f1f5f9;--text-secondary: #94a3b8;--text-muted: #64748b;--accent-blue: #3b82f6;--accent-blue-glow: rgba(59, 130, 246, .3);--accent-emerald: #10b981;--accent-emerald-glow: rgba(16, 185, 129, .3);--accent-purple: #8b5cf6;--accent-amber: #f59e0b;--accent-red: #ef4444;--accent-red-glow: rgba(239, 68, 68, .3);--gradient-primary: linear-gradient(135deg, #3b82f6, #8b5cf6);--gradient-success: linear-gradient(135deg, #10b981, #3b82f6);--gradient-danger: linear-gradient(135deg, #ef4444, #f59e0b);--gradient-bg: radial-gradient(ellipse at top, #1e1b4b 0%, #0a0e1a 50%);--space-xs: .25rem;--space-sm: .5rem;--space-md: 1rem;--space-lg: 1.5rem;--space-xl: 2rem;--space-2xl: 3rem;--radius-sm: .5rem;--radius-md: .75rem;--radius-lg: 1rem;--radius-xl: 1.5rem;--radius-full: 9999px;--shadow-sm: 0 1px 3px rgba(0,0,0,.3);--shadow-md: 0 4px 12px rgba(0,0,0,.4);--shadow-lg: 0 8px 32px rgba(0,0,0,.5);--shadow-glow-blue: 0 0 20px var(--accent-blue-glow);--shadow-glow-emerald: 0 0 20px var(--accent-emerald-glow);--shadow-glow-red: 0 0 20px var(--accent-red-glow);--transition-fast: .15s cubic-bezier(.4, 0, .2, 1);--transition-base: .25s cubic-bezier(.4, 0, .2, 1);--transition-slow: .4s cubic-bezier(.4, 0, .2, 1);--font-sans: "Inter", system-ui, -apple-system, sans-serif;--font-display: "Outfit", "Inter", system-ui, sans-serif}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}*:focus-visible{outline:2px solid var(--accent-blue);outline-offset:2px}input:focus-visible,button:focus-visible,select:focus-visible{outline-offset:4px}html{font-size:16px;scroll-behavior:smooth;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}body{font-family:var(--font-sans);background:var(--gradient-bg);background-attachment:fixed;color:var(--text-primary);min-height:100vh;line-height:1.6}a{color:var(--accent-blue);text-decoration:none}a:hover{text-decoration:underline}h1,h2,h3,h4,h5,h6{font-family:var(--font-display);font-weight:700;line-height:1.2}.container{width:100%;max-width:1200px;margin:0 auto;padding:0 var(--space-lg)}.flex{display:flex}.flex-col{flex-direction:column}.items-center{align-items:center}.justify-center{justify-content:center}.justify-between{justify-content:space-between}.gap-sm{gap:var(--space-sm)}.gap-md{gap:var(--space-md)}.gap-lg{gap:var(--space-lg)}.text-center{text-align:center}.w-full{width:100%}.glass-card{background:var(--bg-glass);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);border:1px solid var(--border-glass);border-radius:var(--radius-lg);padding:var(--space-xl);box-shadow:var(--shadow-md);transition:transform var(--transition-base),box-shadow var(--transition-base)}.glass-card:hover{transform:translateY(-2px);box-shadow:var(--shadow-lg)}.btn{display:inline-flex;align-items:center;justify-content:center;gap:var(--space-sm);padding:.75rem 1.5rem;font-family:var(--font-sans);font-size:.9rem;font-weight:600;border:none;border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast);position:relative;overflow:hidden;text-decoration:none}.btn:disabled{opacity:.5;cursor:not-allowed}.btn:after{content:"";position:absolute;inset:0;background:linear-gradient(rgba(255,255,255,.15),transparent);opacity:0;transition:opacity var(--transition-fast)}.btn:before{content:"";position:absolute;top:0;left:-100%;width:50%;height:100%;background:linear-gradient(to right,transparent,rgba(255,255,255,.2),transparent);transform:skew(-20deg);transition:left .5s ease-out}.btn:hover:before{left:150%}.btn:hover:after{opacity:1}.btn-primary{background:var(--gradient-primary);color:#fff;box-shadow:var(--shadow-glow-blue)}.btn-primary:hover{box-shadow:0 0 30px var(--accent-blue-glow)}.btn-success{background:var(--gradient-success);color:#fff;box-shadow:var(--shadow-glow-emerald)}.btn-danger{background:var(--gradient-danger);color:#fff;box-shadow:var(--shadow-glow-red)}.btn-ghost{background:transparent;color:var(--text-secondary);border:1px solid var(--border-glass)}.btn-ghost:hover{background:var(--bg-glass);color:var(--text-primary)}.btn-sm{padding:.5rem 1rem;font-size:.8rem}.btn-lg{padding:1rem 2rem;font-size:1rem}.input-group{display:flex;flex-direction:column;gap:var(--space-xs)}.input-group label{font-size:.85rem;font-weight:500;color:var(--text-secondary)}.input{padding:.75rem 1rem;background:#0000004d;border:1px solid var(--border-glass);border-radius:var(--radius-md);color:var(--text-primary);font-family:var(--font-sans);font-size:.95rem;transition:border-color var(--transition-fast),box-shadow var(--transition-fast);outline:none}.input:focus{border-color:var(--accent-blue);box-shadow:0 0 0 3px var(--accent-blue-glow)}.input::placeholder{color:var(--text-muted)}select.input{appearance:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 1rem center;padding-right:2.5rem}.badge{display:inline-flex;align-items:center;padding:.25rem .75rem;font-size:.75rem;font-weight:600;border-radius:var(--radius-full);text-transform:uppercase;letter-spacing:.05em}.badge-blue{background:#3b82f626;color:var(--accent-blue)}.badge-green{background:#10b98126;color:var(--accent-emerald)}.badge-red{background:#ef444426;color:var(--accent-red)}.badge-amber{background:#f59e0b26;color:var(--accent-amber)}.badge-purple{background:#8b5cf626;color:var(--accent-purple)}.timer-ring{position:relative;display:inline-flex;align-items:center;justify-content:center}.timer-ring svg{transform:rotate(-90deg)}.timer-ring .timer-text{position:absolute;font-family:var(--font-display);font-weight:700;font-size:1.5rem}.timer-ring.warning .timer-text{color:var(--accent-amber)}.timer-ring.critical .timer-text{color:var(--accent-red)}.modal-overlay{position:fixed;inset:0;background:#000000b3;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);display:flex;align-items:center;justify-content:center;z-index:1000;animation:fadeIn var(--transition-fast) ease-out}.modal-content{background:var(--bg-secondary);border:1px solid var(--border-glass);border-radius:var(--radius-xl);padding:var(--space-2xl);max-width:500px;width:90%;box-shadow:var(--shadow-lg);animation:slideUp var(--transition-base) ease-out}.modal-title{font-size:1.25rem;margin-bottom:var(--space-md)}.spinner{width:40px;height:40px;border:3px solid var(--border-glass);border-top-color:var(--accent-blue);border-radius:50%;animation:spin .8s linear infinite}.spinner-sm{width:20px;height:20px;border-width:2px}.violation-banner{position:fixed;top:0;left:0;right:0;padding:var(--space-md) var(--space-lg);background:#ef4444f2;color:#fff;font-weight:600;text-align:center;z-index:9999;animation:slideDown var(--transition-fast) ease-out;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px)}.leaderboard-row{display:flex;align-items:center;gap:var(--space-md);padding:var(--space-md) var(--space-lg);border-bottom:1px solid var(--border-glass);transition:background var(--transition-fast)}.leaderboard-row:hover{background:var(--bg-glass)}.leaderboard-rank{width:2.5rem;height:2.5rem;border-radius:50%;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:.9rem}.leaderboard-rank.gold{background:linear-gradient(135deg,#f59e0b,#eab308);color:#1a1a1a}.leaderboard-rank.silver{background:linear-gradient(135deg,#94a3b8,#cbd5e1);color:#1a1a1a}.leaderboard-rank.bronze{background:linear-gradient(135deg,#b45309,#d97706);color:#fff}.exam-container{min-height:100vh;display:flex;flex-direction:column;background:var(--bg-primary);user-select:none;-webkit-user-select:none}.exam-header{display:flex;align-items:center;justify-content:space-between;padding:var(--space-md) var(--space-xl);border-bottom:1px solid var(--border-glass);background:var(--bg-glass)}.exam-body{flex:1;display:flex;align-items:center;justify-content:center;padding:var(--space-2xl)}.question-card{width:100%;max-width:700px}.question-text{font-size:1.2rem;font-weight:500;margin-bottom:var(--space-xl);line-height:1.7}.option-btn{display:block;width:100%;padding:var(--space-md) var(--space-lg);margin-bottom:var(--space-sm);background:#0003;border:2px solid var(--border-glass);border-radius:var(--radius-md);color:var(--text-primary);font-size:1rem;text-align:left;cursor:pointer;transition:all var(--transition-fast);animation:slideUp .3s ease-out backwards}.option-btn:nth-child(1){animation-delay:.1s}.option-btn:nth-child(2){animation-delay:.2s}.option-btn:nth-child(3){animation-delay:.3s}.option-btn:nth-child(4){animation-delay:.4s}.option-btn:hover{border-color:var(--accent-blue);background:#3b82f61a}.option-btn.selected{border-color:var(--accent-blue);background:#3b82f626;box-shadow:var(--shadow-glow-blue)}.option-btn.correct{border-color:var(--accent-emerald);background:#10b98126}.option-btn.incorrect{border-color:var(--accent-red);background:#ef444426}.progress-bar{width:100%;height:4px;background:#ffffff1a;border-radius:var(--radius-full);overflow:hidden}.progress-fill{height:100%;background:var(--gradient-primary);border-radius:var(--radius-full);transition:width var(--transition-base)}.stat-card{text-align:center;padding:var(--space-lg)}.stat-value{font-family:var(--font-display);font-size:2rem;font-weight:800;background:var(--gradient-primary);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.stat-label{font-size:.8rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.1em;margin-top:var(--space-xs)}.auth-page{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:var(--space-xl)}.auth-card{width:100%;max-width:420px}.auth-card .logo{font-family:var(--font-display);font-size:2rem;font-weight:800;background:var(--gradient-primary);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;text-align:center;margin-bottom:var(--space-xs)}.auth-card .subtitle{text-align:center;color:var(--text-muted);font-size:.9rem;margin-bottom:var(--space-xl)}.auth-form{display:flex;flex-direction:column;gap:var(--space-md)}.auth-footer{text-align:center;margin-top:var(--space-lg);font-size:.85rem;color:var(--text-muted)}.dashboard{display:flex;min-height:100vh}.sidebar{width:260px;background:var(--bg-glass);border-right:1px solid var(--border-glass);padding:var(--space-lg);display:flex;flex-direction:column;-webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px)}.sidebar-logo{font-family:var(--font-display);font-size:1.4rem;font-weight:800;background:var(--gradient-primary);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;padding:var(--space-md) 0;border-bottom:1px solid var(--border-glass);margin-bottom:var(--space-lg)}.sidebar-nav{display:flex;flex-direction:column;gap:var(--space-xs);flex:1}.sidebar-link{display:flex;align-items:center;gap:var(--space-sm);padding:.6rem var(--space-md);border-radius:var(--radius-md);color:var(--text-secondary);font-size:.9rem;font-weight:500;transition:all var(--transition-fast);cursor:pointer;border:none;background:none;text-align:left;width:100%}.sidebar-link:hover,.sidebar-link.active{background:var(--bg-glass);color:var(--text-primary);text-decoration:none}.sidebar-link.active{border-left:3px solid var(--accent-blue)}.main-content{flex:1;padding:var(--space-xl) var(--space-2xl);overflow-y:auto}.page-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:var(--space-xl)}.page-title{font-size:1.75rem;font-weight:700}.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:var(--space-lg)}.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:var(--space-lg)}.grid-4{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--space-lg)}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes slideDown{0%{transform:translateY(-100%)}to{transform:translateY(0)}}@keyframes spin{to{transform:rotate(360deg)}}@keyframes pulse{0%,to{opacity:1}50%{opacity:.5}}@keyframes glow{0%,to{box-shadow:0 0 5px var(--accent-blue-glow)}50%{box-shadow:0 0 25px var(--accent-blue-glow)}}.animate-fade-in{animation:fadeIn var(--transition-base) ease-out}.animate-slide-up{animation:slideUp var(--transition-base) ease-out}.animate-pulse{animation:pulse 2s ease-in-out infinite}@media(max-width:1024px){.grid-4{grid-template-columns:repeat(2,1fr)}}@media(max-width:768px){.sidebar{position:fixed;bottom:0;left:0;width:100%;height:60px;flex-direction:row;padding:0 var(--space-md);z-index:100;border-right:none;border-top:1px solid var(--border-color)}.sidebar-nav{flex-direction:row;justify-content:space-around;width:100%}.sidebar-link{padding:var(--space-sm);flex-direction:column;font-size:.75rem;gap:4px}.sidebar-link i{font-size:1.25rem}.sidebar-footer{display:none}.layout-container{display:block;padding-bottom:60px}.main-content{padding:var(--space-md);margin-left:0}.grid-2,.grid-3,.grid-4{grid-template-columns:1fr}.page-header{flex-direction:column;gap:var(--space-md);align-items:flex-start}.card{padding:var(--space-md)}.quiz-option{padding:var(--space-md);font-size:.9rem}.btn{width:100%;justify-content:center}}@media(max-width:480px){:root{--space-xl: 1.5rem;--space-2xl: 2rem}.page-title{font-size:1.5rem}.card-title{font-size:1.1rem}}.student-stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:var(--space-md);margin-bottom:var(--space-xl)}.stat-box{background:var(--glass-bg);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);padding:var(--space-lg);border-radius:var(--radius-lg);border:1px solid var(--border-glass);display:flex;flex-direction:column;gap:var(--space-xs);transition:transform .2s ease}.stat-box:hover{transform:translateY(-4px);border-color:var(--accent-blue)}.stat-box .label{font-size:.85rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.05em}.stat-box .value{font-size:2rem;font-weight:800;font-family:var(--font-display)}.join-section{background:linear-gradient(135deg,#3b82f61a,#8b5cf61a);border:2px dashed rgba(59,130,246,.3);padding:var(--space-xl);border-radius:var(--radius-xl);margin-bottom:var(--space-2xl);text-align:center}.join-input{max-width:400px;margin:var(--space-lg) auto;position:relative}.join-input input{width:100%;padding:var(--space-lg);font-size:1.5rem;text-align:center;letter-spacing:.2em;font-family:var(--font-mono);background:#0000004d;border:2px solid var(--border-glass);border-radius:var(--radius-md);color:var(--accent-blue);text-transform:uppercase}.join-input input:focus{border-color:var(--accent-blue);outline:none;box-shadow:0 0 20px #3b82f633}.past-quiz-card{display:flex;align-items:center;gap:var(--space-lg);padding:var(--space-lg);background:var(--glass-bg);border:1px solid var(--border-glass);border-radius:var(--radius-lg);margin-bottom:var(--space-md);transition:all .2s ease}.past-quiz-card:hover{background:#ffffff0d;transform:translate(4px)}.quiz-icon{width:48px;height:48px;background:#3b82f61a;border-radius:var(--radius-md);display:flex;align-items:center;justify-content:center;font-size:1.5rem}