:root{--bg-primary: #0a0a0a;--bg-secondary: #111111;--bg-card: #161616;--bg-elevated: #1c1c1c;--bg-hover: #222222;--bg-active: #2a2a2a;--bg-input: #141414;--border-subtle: #1f1f1f;--border-default: #2a2a2a;--border-strong: #3a3a3a;--border-focus: #555555;--text-primary: #f0f0f0;--text-secondary: #a0a0a0;--text-muted: #606060;--text-disabled: #404040;--accent: #ffffff;--accent-dim: rgba(255,255,255,.08);--accent-hover: rgba(255,255,255,.12);--success: #4ade80;--success-bg: rgba(74, 222, 128, .08);--warning: #fbbf24;--warning-bg: rgba(251, 191, 36, .08);--danger: #f87171;--danger-bg: rgba(248, 113, 113, .08);--info: #60a5fa;--info-bg: rgba(96, 165, 250, .08);--verified: #4ade80;--shadow-sm: 0 1px 3px rgba(0,0,0,.6);--shadow-md: 0 4px 12px rgba(0,0,0,.7);--shadow-lg: 0 8px 32px rgba(0,0,0,.8);--gradient-accent: linear-gradient(135deg, #6366f1, #8b5cf6, #a78bfa);--gradient-warm: linear-gradient(135deg, #f59e0b, #ef4444);--gradient-cool: linear-gradient(135deg, #06b6d4, #3b82f6);--gradient-success: linear-gradient(135deg, #10b981, #34d399);--radius-sm: 6px;--radius-md: 10px;--radius-lg: 16px;--radius-xl: 24px;--radius-full: 9999px;--transition: all .2s cubic-bezier(.4, 0, .2, 1);--transition-slow: all .35s cubic-bezier(.4, 0, .2, 1);--font-body: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;--font-heading: "Space Grotesk", "Inter", sans-serif}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:16px;scroll-behavior:smooth}body{font-family:var(--font-body);background-color:var(--bg-primary);color:var(--text-primary);line-height:1.6;min-height:100vh;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}button{cursor:pointer;font-family:inherit}input,textarea,select{font-family:inherit}img{max-width:100%;display:block}ul{list-style:none}::-webkit-scrollbar{width:6px;height:6px}::-webkit-scrollbar-track{background:var(--bg-secondary)}::-webkit-scrollbar-thumb{background:var(--border-strong);border-radius:8px}::-webkit-scrollbar-thumb:hover{background:var(--text-muted)}h1,h2,h3,h4,h5,h6{font-family:var(--font-heading);font-weight:700;line-height:1.2;color:var(--text-primary)}h1{font-size:2.25rem}h2{font-size:1.75rem}h3{font-size:1.375rem}h4{font-size:1.125rem}p{color:var(--text-secondary)}.container{max-width:1280px;margin:0 auto;padding:0 24px}.page{min-height:calc(100vh - 72px);padding:40px 24px;max-width:1280px;margin:0 auto}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:10px 20px;border-radius:var(--radius-md);font-size:.875rem;font-weight:600;border:1px solid transparent;transition:var(--transition);white-space:nowrap;outline:none}.btn:disabled{opacity:.4;cursor:not-allowed}.btn-primary{background:var(--accent);color:#000;border-color:var(--accent)}.btn-primary:hover:not(:disabled){background:#e0e0e0;transform:translateY(-1px);box-shadow:0 4px 16px #fff3}.btn-secondary{background:transparent;color:var(--text-primary);border-color:var(--border-strong)}.btn-secondary:hover:not(:disabled){background:var(--bg-hover);border-color:var(--border-focus)}.btn-ghost{background:transparent;color:var(--text-secondary);border-color:transparent}.btn-ghost:hover:not(:disabled){background:var(--bg-hover);color:var(--text-primary)}.btn-danger{background:var(--danger-bg);color:var(--danger);border-color:#f8717133}.btn-danger:hover:not(:disabled){background:#f8717126}.btn-success{background:var(--success-bg);color:var(--success);border-color:#4ade8033}.btn-success:hover:not(:disabled){background:#4ade8026}.btn-sm{padding:6px 14px;font-size:.8rem}.btn-lg{padding:14px 28px;font-size:1rem}.btn-full{width:100%}.btn-icon{padding:8px;border-radius:var(--radius-sm)}.card{background:var(--bg-card);border:1px solid var(--border-subtle);border-radius:var(--radius-lg);padding:24px;transition:var(--transition-slow);position:relative}.card:hover{border-color:var(--border-strong);box-shadow:var(--shadow-md);transform:translateY(-2px)}.card-elevated{background:var(--bg-elevated);border-color:var(--border-default)}.form-group{display:flex;flex-direction:column;gap:6px;margin-bottom:20px}.form-label{font-size:.8rem;font-weight:600;color:var(--text-secondary);text-transform:uppercase;letter-spacing:.05em}.form-input,.form-select,.form-textarea{background:var(--bg-input);border:1px solid var(--border-default);border-radius:var(--radius-md);color:var(--text-primary);font-size:.9rem;padding:12px 16px;transition:var(--transition);outline:none;width:100%}.form-input::placeholder,.form-textarea::placeholder{color:var(--text-muted)}.form-input:focus,.form-select:focus,.form-textarea:focus{border-color:var(--border-focus);background:var(--bg-secondary);box-shadow:0 0 0 3px #ffffff0a}.form-select option{background:var(--bg-card)}.form-textarea{resize:vertical;min-height:100px}.form-error{font-size:.8rem;color:var(--danger);margin-top:4px}.badge{display:inline-flex;align-items:center;gap:4px;padding:3px 10px;border-radius:var(--radius-full);font-size:.72rem;font-weight:600;text-transform:uppercase;letter-spacing:.04em}.badge-verified{background:#4ade801a;color:var(--verified);border:1px solid rgba(74,222,128,.2)}.badge-pending{background:var(--warning-bg);color:var(--warning);border:1px solid rgba(251,191,36,.2)}.badge-success{background:var(--success-bg);color:var(--success);border:1px solid rgba(74,222,128,.2)}.badge-danger{background:var(--danger-bg);color:var(--danger);border:1px solid rgba(248,113,113,.2)}.badge-info{background:var(--info-bg);color:var(--info);border:1px solid rgba(96,165,250,.2)}.badge-grey{background:var(--bg-elevated);color:var(--text-secondary);border:1px solid var(--border-default)}.badge-warning{background:var(--warning-bg);color:var(--warning);border:1px solid rgba(251,191,36,.2)}.navbar{position:sticky;top:0;z-index:100;background:#0a0a0ad9;-webkit-backdrop-filter:blur(24px) saturate(180%);backdrop-filter:blur(24px) saturate(180%);border-bottom:1px solid rgba(255,255,255,.06);height:72px;display:flex;align-items:center}.navbar-inner{width:100%;max-width:1280px;margin:0 auto;padding:0 24px;display:flex;align-items:center;gap:16px}.navbar-logo{font-family:var(--font-heading);font-size:1.25rem;font-weight:800;color:var(--text-primary);display:flex;align-items:center;gap:8px;margin-right:16px;letter-spacing:-.02em}.navbar-logo-dot{width:8px;height:8px;background:var(--accent);border-radius:50%;animation:pulse 2s infinite}.navbar-nav{display:flex;align-items:center;gap:4px;flex:1}.navbar-link{padding:8px 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transparent}.alert-success{background:var(--success-bg);border-color:#4ade8033;color:var(--success)}.alert-danger{background:var(--danger-bg);border-color:#f8717133;color:var(--danger)}.alert-warning{background:var(--warning-bg);border-color:#fbbf2433;color:var(--warning)}.alert-info{background:var(--info-bg);border-color:#60a5fa33;color:var(--info)}.tabs{display:flex;background:var(--bg-secondary);border:1px solid var(--border-default);border-radius:var(--radius-lg);padding:4px;gap:4px;overflow-x:auto}.tab-btn{flex:1;padding:10px 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var(--border-subtle);overflow:hidden}.chat-messages{flex:1;overflow-y:auto;padding:20px;display:flex;flex-direction:column;gap:12px;min-height:0}.chat-message{display:flex;gap:10px;max-width:80%;animation:fadeIn .2s ease}.chat-message.own{margin-left:auto;flex-direction:row-reverse}.message-bubble{padding:10px 14px;border-radius:18px;font-size:.875rem;line-height:1.5;word-break:break-word;border:1px solid transparent}.chat-message.other .message-bubble{background:var(--bg-elevated);border-color:var(--border-subtle);color:var(--text-primary);border-top-left-radius:4px}.chat-message.own .message-bubble{background:var(--bg-active);border-color:var(--border-default);color:var(--text-primary);border-top-right-radius:4px}.chat-message.flagged .message-bubble{background:var(--warning-bg);border-color:#fbbf2433}.message-meta{font-size:.7rem;color:var(--text-muted);margin-top:4px;text-align:right}.chat-input-area{padding:16px 20px;border-top:1px solid 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var(--border-default);border-radius:var(--radius-lg);padding:24px;margin-bottom:16px}.question-number{font-size:.75rem;font-weight:700;color:var(--text-muted);text-transform:uppercase;letter-spacing:.08em;margin-bottom:10px}.question-text{font-size:1rem;font-weight:600;color:var(--text-primary);margin-bottom:18px;line-height:1.5}.options-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}.option-btn{padding:12px 16px;background:var(--bg-secondary);border:1px solid var(--border-default);border-radius:var(--radius-md);color:var(--text-primary);font-size:.875rem;text-align:left;transition:var(--transition);cursor:pointer;display:flex;align-items:center;gap:10px}.option-btn:hover:not(:disabled){border-color:var(--border-focus);background:var(--bg-hover)}.option-btn.selected{border-color:var(--text-primary);background:var(--accent-dim)}.option-key{width:24px;height:24px;border-radius:50%;background:var(--bg-elevated);border:1px solid 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cubic-bezier(.4,0,.2,1);position:relative;z-index:1;box-shadow:0 16px 64px #00000080}.auth-logo{text-align:center;font-family:var(--font-heading);font-size:1.75rem;font-weight:800;margin-bottom:8px;letter-spacing:-.02em}.auth-subtitle{text-align:center;color:var(--text-muted);font-size:.875rem;margin-bottom:32px}.auth-link{text-align:center;font-size:.875rem;color:var(--text-muted);margin-top:24px}.auth-link a{color:var(--text-primary);font-weight:600;text-decoration:underline;text-underline-offset:3px}.stat-card{background:var(--bg-card);border:1px solid var(--border-subtle);border-radius:var(--radius-lg);padding:20px 24px;display:flex;align-items:center;gap:16px;transition:var(--transition-slow);border-top-width:3px;border-top-style:solid}.stat-card:hover{border-color:var(--border-default);transform:translateY(-4px);box-shadow:0 8px 24px #0009}.stat-icon{width:44px;height:44px;border-radius:var(--radius-md);background:var(--bg-elevated);display:flex;align-items:center;justify-content:center;font-size:1.25rem;flex-shrink:0}.stat-value{font-family:var(--font-heading);font-size:1.75rem;font-weight:700;color:var(--text-primary);line-height:1}.stat-label{font-size:.78rem;color:var(--text-muted);margin-top:4px;text-transform:uppercase;letter-spacing:.04em}.teacher-card{background:var(--bg-card);border:1px solid var(--border-subtle);border-radius:var(--radius-lg);padding:20px;display:flex;flex-direction:column;gap:14px;transition:var(--transition-slow);cursor:pointer}.teacher-card:hover{border-color:var(--border-strong);box-shadow:var(--shadow-md);transform:translateY(-2px)}.request-card{background:var(--bg-card);border:1px solid var(--border-subtle);border-radius:var(--radius-lg);padding:20px;display:flex;align-items:flex-start;gap:16px;transition:var(--transition)}.request-card:hover{border-color:var(--border-default)}.flex{display:flex}.flex-col{flex-direction:column}.items-center{align-items:center}.justify-between{justify-content:space-between}.gap-2{gap:8px}.gap-3{gap:12px}.gap-4{gap:16px}.mt-2{margin-top:8px}.mt-4{margin-top:16px}.mb-2{margin-bottom:8px}.mb-4{margin-bottom:16px}.text-sm{font-size:.875rem}.text-xs{font-size:.75rem}.text-muted{color:var(--text-muted)}.font-bold{font-weight:700}.truncate{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}@keyframes spin{to{transform:rotate(360deg)}}@keyframes pulse{0%,to{opacity:1}50%{opacity:.4}}@keyframes bounce{0%,80%,to{transform:translateY(0)}40%{transform:translateY(-4px)}}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideUp{0%{transform:translateY(20px);opacity:0}to{transform:translateY(0);opacity:1}}@keyframes authOrb1{0%{transform:translate(0) scale(1)}to{transform:translate(10%,15%) scale(1.1)}}@keyframes authOrb2{0%{transform:translate(0) scale(1)}to{transform:translate(-8%,-10%) scale(1.15)}}@keyframes timerPulse{0%{opacity:1}to{opacity:.5}}@keyframes splashEntrance{0%{transform:scale(.8) translateY(20px);opacity:0}to{transform:scale(1) translateY(0);opacity:1}}@media(max-width:768px){h1{font-size:1.625rem}.page{padding:24px 16px}.grid-2,.grid-3,.grid-4,.options-grid{grid-template-columns:1fr}.modal{padding:24px}.navbar-nav{display:none}.auth-card{padding:28px 24px}}