:root{--primary: #1677FF;--primary-dark: #0B1F3A;--primary-light:#E5F0FF;--accent: #22C55E;--accent-dark: #16A34A;--success: #28a745;--danger: #dc3545;--warning: #fd7e14;--text: #333333;--text-muted: #6c757d;--light: #F1F5F9;--white: #ffffff;--border: #dee2e6;--shadow: 0 4px 12px rgba(22,119,255,.12);--shadow-sm: 0 2px 6px rgba(0,0,0,.08);--gradient: linear-gradient(135deg,#1677FF 0%,#0B1F3A 100%);--radius: 12px;--radius-sm: 8px;--radius-lg: 16px;--sidebar-w: 240px}*{box-sizing:border-box;margin:0;padding:0}body{font-family:Segoe UI,system-ui,-apple-system,sans-serif;color:var(--text);background:var(--light);min-height:100vh}#root{min-height:100vh}h1{font-size:1.75rem;font-weight:700;color:var(--primary-dark)}h2{font-size:1.375rem;font-weight:600;color:var(--primary-dark)}h3{font-size:1.125rem;font-weight:600;color:var(--text)}p{line-height:1.6;color:var(--text)}.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;cursor:pointer;border:none;transition:all .2s;text-decoration:none;font-family:inherit;white-space:nowrap}.btn-primary{background:var(--gradient);color:#fff}.btn-primary:hover{opacity:.92;transform:translateY(-1px);box-shadow:var(--shadow)}.btn-accent{background:var(--accent);color:#1a1d27}.btn-accent:hover{background:var(--accent-dark);transform:translateY(-1px)}.btn-outline{background:transparent;color:var(--primary);border:2px solid var(--primary)}.btn-outline:hover{background:var(--primary);color:#fff}.btn-danger{background:#c0392b;color:#fff}.btn-success{background:#1e7e34;color:#fff}.btn-ghost{background:transparent;color:var(--text-muted)}.btn-ghost:hover{background:var(--light)}.btn-sm{padding:6px 14px;font-size:.8rem}.btn-lg{padding:14px 28px;font-size:1rem}.btn-full{width:100%}.btn:disabled{opacity:.5;cursor:not-allowed;transform:none!important}.card{background:var(--white);border-radius:var(--radius);box-shadow:var(--shadow-sm);padding:20px;border:1px solid var(--border)}.card-header{padding:16px 20px;border-bottom:1px solid var(--border);font-weight:600;color:var(--primary-dark)}.input-group{display:flex;flex-direction:column;gap:6px;margin-bottom:16px}.input-group label{font-size:.85rem;font-weight:600;color:var(--text)}.input-field{padding:11px 14px;border:1.5px solid var(--border);border-radius:var(--radius-sm);font-size:.95rem;font-family:inherit;color:var(--text);transition:border .2s;background:var(--white);width:100%}.input-field:focus{outline:none;border-color:var(--primary)}.input-field::placeholder{color:#9ca3af}select.input-field{cursor:pointer;appearance:none;-webkit-appearance:none;-moz-appearance:none;padding-right:38px;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 12px center;background-size:16px}textarea.input-field{resize:vertical;min-height:80px}.badge{display:inline-flex;align-items:center;padding:3px 10px;border-radius:20px;font-size:.75rem;font-weight:600}.badge-primary{background:var(--primary-light);color:var(--primary)}.badge-accent{background:#fff8e1;color:#664d03}.badge-success{background:#e8f5e9;color:#1b6b2c}.badge-danger{background:#fdecea;color:#b71c1c}.badge-muted{background:#f0f0f0;color:var(--text-muted)}.table{width:100%;border-collapse:collapse;font-size:.85rem}.table th,.table td{padding:8px 10px;border-bottom:1px solid var(--border);text-align:left}.table th{font-weight:600;color:var(--text-muted);font-size:.72rem;text-transform:uppercase;letter-spacing:.04em;background:var(--light);white-space:nowrap}.table tbody tr:hover{background:var(--light)}.progress-bar{height:6px;background:var(--border);border-radius:3px;overflow:hidden}.progress-fill{height:100%;background:var(--gradient);border-radius:3px;transition:width .5s ease}.progress-fill.accent{background:var(--accent)}.progress-fill.success{background:var(--success)}.app-shell{min-height:100vh;background:var(--white)}.page-wrapper{min-height:100vh;display:flex;flex-direction:column}.page-content{flex:1;padding:16px 16px 80px;max-width:100%}.top-header{background:var(--gradient);padding:14px 16px;display:flex;align-items:center;justify-content:space-between;position:sticky;top:0;z-index:20;box-shadow:0 2px 8px #1677ff33;flex-shrink:0}.top-header .logo{display:flex;align-items:center;gap:10px}.logo-badge{width:64px;height:64px;border-radius:12px;object-fit:cover;flex-shrink:0}.logo-text{color:#fff;font-weight:700;font-size:1rem;line-height:1.2}.logo-sub{color:#ffffffd9;font-size:.7rem}.bottom-nav{position:fixed;bottom:0;left:0;right:0;background:var(--white);border-top:1px solid var(--border);display:flex;padding:6px 0 10px;z-index:100;box-shadow:0 -2px 12px #00000014}.bottom-nav-item{flex:1;display:flex;flex-direction:column;align-items:center;gap:3px;cursor:pointer;padding:4px;color:var(--text-muted);transition:color .2s;background:none;border:none;font-family:inherit}.bottom-nav-item.active{color:var(--primary)}.bottom-nav-item span{font-size:9px;font-weight:500}.bottom-nav-icon{font-size:20px;line-height:1}.bottom-nav-dot{width:4px;height:4px;border-radius:50%;background:var(--primary)}@media (min-width: 768px){.page-content{padding:24px 24px 90px;max-width:100%;margin:0;width:100%}.stats-grid{grid-template-columns:repeat(4,1fr)!important}.top-header{padding:16px 24px}.top-header .logo-text{font-size:1.1rem}}@media (min-width: 1024px){.app-shell{display:flex;min-height:100vh}.sidebar{width:var(--sidebar-w);min-height:100vh;background:var(--white);border-right:1px solid var(--border);display:flex;flex-direction:column;position:fixed;left:0;top:0;bottom:0;z-index:50;box-shadow:2px 0 8px #0000000f;overflow-y:auto}.sidebar-logo{padding:20px 18px 16px;border-bottom:1px solid var(--border);display:flex;align-items:center;gap:10px;background:var(--gradient)}.sidebar-nav{flex:1;padding:12px 10px;display:flex;flex-direction:column;gap:2px}.sidebar-item{display:flex;align-items:center;gap:10px;padding:10px 12px;border-radius:var(--radius-sm);cursor:pointer;color:var(--text-muted);font-size:.9rem;font-weight:500;transition:all .15s;border:none;background:none;font-family:inherit;text-decoration:none;width:100%;text-align:left}.sidebar-item:hover{background:var(--light);color:var(--text)}.sidebar-item.active{background:var(--primary-light);color:var(--primary);font-weight:600}.sidebar-item .s-icon{font-size:18px;width:22px;text-align:center;flex-shrink:0}.sidebar-item .s-dot{width:6px;height:6px;border-radius:50%;background:var(--primary);margin-left:auto}.s-badge{margin-left:auto;background:#dc2626;color:#fff;font-size:.65rem;font-weight:700;line-height:1;padding:2px 6px;border-radius:999px;min-width:16px;text-align:center}.sidebar-footer{padding:12px 10px 20px;border-top:1px solid var(--border)}.bottom-nav{display:none!important}.page-wrapper{margin-left:var(--sidebar-w);min-height:100vh;flex:1;min-width:0;width:calc(100% - var(--sidebar-w))}.top-header{padding:14px 32px;position:sticky;top:0;z-index:30}.page-content{padding:28px 32px 40px;max-width:100%;margin:0}.stats-grid{grid-template-columns:repeat(4,1fr)!important}.desktop-grid{display:grid;grid-template-columns:1fr 340px;gap:24px;align-items:start}.desktop-grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.auth-card form,.profile-form form{max-width:560px}.auth-page{min-height:100vh;display:flex;align-items:center;justify-content:center;background:var(--light);padding:40px 20px}.auth-card{max-width:440px;width:100%}}@media (min-width: 1280px){.page-content{max-width:100%}:root{--sidebar-w: 260px}}.stats-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-bottom:16px}.stat-card{background:var(--white);border-radius:var(--radius);padding:14px;border:1px solid var(--border);text-align:center}.stat-value{font-size:1.5rem;font-weight:700;color:var(--primary)}.stat-label{font-size:.75rem;color:var(--text-muted);margin-top:2px}.track-card{background:var(--white);border-radius:var(--radius);border:1.5px solid var(--border);padding:16px;cursor:pointer;transition:all .2s;margin-bottom:12px;display:flex;align-items:center;gap:14px}.track-card:hover{border-color:var(--primary);transform:translateY(-1px);box-shadow:var(--shadow)}.track-icon{width:48px;height:48px;border-radius:14px;display:flex;align-items:center;justify-content:center;font-size:22px;flex-shrink:0}.module-card{background:var(--white);border-radius:var(--radius);border:1px solid var(--border);margin-bottom:10px;overflow:hidden;cursor:pointer;transition:all .2s}.module-card:hover{border-color:var(--primary);box-shadow:var(--shadow-sm)}.module-header{padding:14px 16px;display:flex;align-items:center;justify-content:space-between}.lesson-row{padding:12px 16px;display:flex;align-items:center;gap:12px;border-bottom:1px solid var(--border);cursor:pointer;transition:background .15s}.lesson-row:last-child{border-bottom:none}.lesson-row:hover{background:var(--light)}.lesson-row.locked{opacity:.5;cursor:not-allowed}.lesson-row.current{background:var(--primary-light)}.video-wrapper{position:relative;background:#000;border-radius:var(--radius);overflow:hidden;aspect-ratio:16/9}.video-wrapper video,.video-wrapper iframe{width:100%;height:100%}.study-buddy-btn{position:absolute;bottom:12px;right:12px;background:var(--accent);border:none;border-radius:50%;width:44px;height:44px;font-size:22px;cursor:pointer;display:flex;align-items:center;justify-content:center;box-shadow:0 2px 8px #0000004d;transition:transform .2s;z-index:5}.study-buddy-btn:hover{transform:scale(1.1)}.study-buddy-btn.active{background:var(--primary);animation:pulse 1s infinite}@keyframes pulse{0%,to{box-shadow:0 0 #1677ff66}50%{box-shadow:0 0 0 8px #1677ff00}}.study-buddy-panel{background:var(--white);border-radius:var(--radius);border:1.5px solid var(--primary-light);margin-top:10px;overflow:hidden}.study-buddy-panel-header{background:var(--primary-light);padding:10px 14px;display:flex;align-items:center;gap:8px;font-weight:600;font-size:.85rem;color:var(--primary)}.chat-messages{max-height:220px;overflow-y:auto;padding:12px;display:flex;flex-direction:column;gap:8px}.chat-msg{display:flex;gap:8px}.chat-msg.user{flex-direction:row-reverse}.chat-bubble{max-width:80%;padding:8px 12px;border-radius:12px;font-size:.85rem;line-height:1.5;white-space:pre-wrap}.chat-msg.ai .chat-bubble{background:var(--primary-light);color:var(--primary-dark);border-radius:4px 12px 12px}.chat-msg.user .chat-bubble{background:var(--primary);color:#fff;border-radius:12px 4px 12px 12px}.chat-input-row{display:flex;gap:8px;padding:10px 12px;border-top:1px solid var(--border)}.chat-input{flex:1;padding:8px 12px;border:1.5px solid var(--border);border-radius:20px;font-size:.85rem;font-family:inherit;background:var(--light)}.chat-input:focus{outline:none;border-color:var(--primary)}.chat-markdown{white-space:normal}.chat-markdown p{margin:0 0 6px}.chat-markdown p:last-child{margin-bottom:0}.chat-markdown h1,.chat-markdown h2,.chat-markdown h3,.chat-markdown h4,.chat-markdown h5,.chat-markdown h6{margin:8px 0 4px;font-size:.95em;font-weight:700}.chat-markdown h1:first-child,.chat-markdown h2:first-child,.chat-markdown h3:first-child{margin-top:0}.chat-markdown ul,.chat-markdown ol{margin:4px 0 6px;padding-left:20px}.chat-markdown li{margin-bottom:2px}.chat-markdown code{background:#0000000f;border-radius:4px;padding:1px 4px;font-size:.9em;font-family:SFMono-Regular,Consolas,monospace}.chat-markdown pre{background:#0000000f;border-radius:6px;padding:8px;overflow-x:auto;margin:6px 0}.chat-markdown pre code{background:none;padding:0}.chat-markdown table{border-collapse:collapse;width:100%;margin:6px 0;font-size:.92em}.chat-markdown th,.chat-markdown td{border:1px solid rgba(0,0,0,.12);padding:4px 6px;text-align:left}.chat-markdown th{background:#0000000a;font-weight:700}.chat-markdown blockquote{border-left:3px solid rgba(0,0,0,.15);margin:6px 0;padding-left:10px;opacity:.85}.chat-markdown a{color:inherit;text-decoration:underline}[data-theme=dark] .chat-markdown code,[data-theme=dark] .chat-markdown pre{background:#ffffff1a}[data-theme=dark] .chat-markdown th,[data-theme=dark] .chat-markdown td{border-color:#ffffff2e}[data-theme=dark] .chat-markdown th{background:#ffffff0f}[data-theme=dark] .chat-markdown blockquote{border-left-color:#ffffff40}.question-card{background:var(--white);border-radius:var(--radius);border:1px solid var(--border);padding:20px;margin-bottom:16px}.option-btn{width:100%;text-align:left;padding:12px 14px;margin-bottom:8px;border:1.5px solid var(--border);border-radius:var(--radius-sm);background:var(--white);cursor:pointer;font-family:inherit;font-size:.9rem;transition:all .15s}.option-btn:hover{border-color:var(--primary);background:var(--primary-light)}.option-btn.selected{border-color:var(--primary);background:var(--primary-light);color:var(--primary);font-weight:600}.option-btn.correct{border-color:var(--success);background:#e8f5e9;color:#1b6b2c}.option-btn.wrong{border-color:var(--danger);background:#fdecea;color:#b71c1c}.structural-answer{width:100%;padding:12px 14px;border:1.5px solid var(--border);border-radius:var(--radius-sm);font-family:Courier New,monospace;font-size:.9rem;resize:vertical;min-height:100px}.structural-answer:focus{outline:none;border-color:var(--primary)}.timer-bar{height:5px;background:var(--border);border-radius:3px;overflow:hidden;margin-bottom:16px}.timer-fill{height:100%;background:var(--success);border-radius:3px;transition:width 1s linear}.timer-fill.warning{background:var(--warning)}.timer-fill.danger{background:var(--danger)}.announcement-card{background:var(--white);border-radius:var(--radius);border-left:4px solid var(--primary);padding:14px 16px;margin-bottom:12px;box-shadow:var(--shadow-sm)}.announcement-card.urgent{border-left-color:var(--danger)}.announcement-card.event{border-left-color:var(--success)}.announcement-card.result{border-left-color:var(--accent)}.session-card{background:var(--white);border-radius:var(--radius);border:1px solid var(--border);padding:14px 16px;margin-bottom:10px;display:flex;align-items:center;gap:12px}.teacher-avatar{width:44px;height:44px;border-radius:50%;background:var(--gradient);display:flex;align-items:center;justify-content:center;font-weight:700;color:#fff;font-size:1.1rem;flex-shrink:0}.alert{padding:12px 14px;border-radius:var(--radius-sm);margin-bottom:14px;font-size:.9rem;font-weight:500}.alert-error{background:#fdecea;color:#b71c1c;border:1px solid #f5c6cb}.alert-success{background:#e8f5e9;color:#1b6b2c;border:1px solid #c3e6cb}.alert-info{background:var(--primary-light);color:var(--primary-dark);border:1px solid #b8d4f0}.section-title{font-size:.75rem;font-weight:700;color:var(--text-muted);text-transform:uppercase;letter-spacing:.8px;margin-bottom:10px}.text-primary{color:var(--primary)}.text-accent{color:var(--accent-dark)}.text-muted{color:var(--text-muted)}.text-success{color:var(--success)}.text-danger{color:var(--danger)}.text-sm{font-size:.85rem}.text-xs{font-size:.75rem}.fw-600{font-weight:600}.fw-700{font-weight:700}.mt-8{margin-top:8px}.mt-12{margin-top:12px}.mt-16{margin-top:16px}.mt-24{margin-top:24px}.mb-8{margin-bottom:8px}.mb-12{margin-bottom:12px}.mb-16{margin-bottom:16px}.gap-8{gap:8px}.gap-12{gap:12px}.flex{display:flex}.flex-col{flex-direction:column}.items-center{align-items:center}.justify-between{justify-content:space-between}.flex-1{flex:1}.w-full{width:100%}.divider{height:1px;background:var(--border);margin:16px 0}.loading{display:flex;align-items:center;justify-content:center;padding:40px}.spinner{width:32px;height:32px;border:3px solid var(--border);border-top-color:var(--primary);border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.empty-state{text-align:center;padding:40px 20px;color:var(--text-muted)}.empty-state .empty-icon{font-size:3rem;margin-bottom:12px}.nav-pills{display:flex;gap:6px;overflow-x:auto;margin-bottom:12px}.nav-pills::-webkit-scrollbar{height:0}.npill{padding:5px 12px;border-radius:16px;border:1px solid var(--border);background:var(--white);color:var(--text-muted);font-size:.72rem;font-weight:500;cursor:pointer;white-space:nowrap;flex-shrink:0;font-family:inherit;transition:all .15s}.npill.on{background:var(--primary-light);border-color:var(--primary);color:var(--primary);font-weight:600}::-webkit-scrollbar{width:4px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:2px}@media (min-width: 1024px){.mobile-logo-badge,.mobile-logout-btn{display:none!important}}@media (max-width: 1023px){.sidebar{display:none!important}.page-wrapper{margin-left:0!important}}[data-theme=dark]{--primary: #4D8FFF;--primary-dark: #1677FF;--primary-light: #16233D;--accent: #22C55E;--accent-dark: #16A34A;--success: #4ade80;--danger: #f87171;--warning: #fb923c;--text: #e2e8f0;--text-muted: #94a3b8;--light: #0f1117;--white: #1a1d27;--border: #2a2d3e;--shadow: 0 4px 12px rgba(0,0,0,.4);--shadow-sm: 0 2px 6px rgba(0,0,0,.3);--gradient: linear-gradient(135deg,#1E3A5F 0%,#0B1F3A 100%)}[data-theme=dark] body{background:#0f1117;color:#e2e8f0}[data-theme=dark] .card{background:#1a1d27;border-color:#2a2d3e}[data-theme=dark] .app-shell{background:#0f1117}[data-theme=dark] .bottom-nav{background:#1a1d27;border-color:#2a2d3e}[data-theme=dark] .sidebar{background:#13151f;border-color:#2a2d3e}[data-theme=dark] .top-header{background:linear-gradient(135deg,#1e3a5f,#0d2137)}[data-theme=dark] .input-field{background:#252838;border-color:#2a2d3e;color:#e2e8f0}[data-theme=dark] .input-field:focus{border-color:#4d9de0}[data-theme=dark] .input-field::placeholder{color:#4a5568}[data-theme=dark] .track-card,[data-theme=dark] .module-card,[data-theme=dark] .lesson-row,[data-theme=dark] .session-card,[data-theme=dark] .announcement-card{background:#1a1d27;border-color:#2a2d3e}[data-theme=dark] .lesson-row:hover,[data-theme=dark] .track-card:hover{background:#252838}[data-theme=dark] .lesson-row.current{background:#1a2744}[data-theme=dark] .stat-card{background:#1a1d27;border-color:#2a2d3e}[data-theme=dark] .option-btn{background:#1a1d27;border-color:#2a2d3e;color:#e2e8f0}[data-theme=dark] .option-btn:hover,[data-theme=dark] .option-btn.selected{background:#1a2744;border-color:#4d9de0;color:#4d9de0}[data-theme=dark] .structural-answer,[data-theme=dark] .chat-input{background:#252838;border-color:#2a2d3e;color:#e2e8f0}[data-theme=dark] .npill{background:#1a1d27;border-color:#2a2d3e;color:#94a3b8}[data-theme=dark] .npill.on{background:#1a2744;border-color:#4d9de0;color:#4d9de0}[data-theme=dark] .study-buddy-panel{background:#1a1d27;border-color:#2a2d3e}[data-theme=dark] .study-buddy-panel-header{background:#1a2744}[data-theme=dark] .chat-msg.ai .chat-bubble{background:#1a2744;color:#93c5fd}[data-theme=dark] .page-wrapper{background:#0f1117}[data-theme=dark] .alert-info{background:#1a2744;border-color:#2a4a7f;color:#93c5fd}[data-theme=dark] .alert-success{background:#14291a;border-color:#166534;color:#4ade80}[data-theme=dark] .alert-error{background:#2a1515;border-color:#7f1d1d;color:#f87171}[data-theme=dark] .sidebar-item:hover{background:#252838}[data-theme=dark] .sidebar-item.active{background:#1a2744;color:#4d9de0}[data-theme=dark] .progress-bar{background:#2a2d3e}[data-theme=dark] h1,[data-theme=dark] h2{color:#e2e8f0}[data-theme=dark] h3{color:#cbd5e1}[data-theme=dark] .btn-success{background:#166534}[data-theme=dark] .btn-danger{background:#b91c1c}[data-theme=dark] .badge-muted{background:#2a2d3e;color:#94a3b8}[data-theme=dark] .badge-accent{background:#10291a;color:#22c55e}[data-theme=dark] p{color:#94a3b8}.auth-right{background:#f8fafc;color:#1e293b}.auth-right .input-field{color:#111827;font-weight:500}[data-theme=dark] .auth-right{background:#f8fafc;color:#1e293b}[data-theme=dark] .auth-right .input-field{background:#fff!important;color:#111827!important;border-color:#e2e8f0;font-weight:500}[data-theme=dark] .auth-right .input-field::placeholder{color:#94a3b8!important}[data-theme=dark] .auth-right .card{background:#fff;border-color:#e2e8f0;color:#1e293b}[data-theme=dark] .auth-right .alert-info,[data-theme=dark] .auth-right .alert-error,[data-theme=dark] .auth-right .alert-success{background:revert;border-color:revert;color:revert}html,body,.card,.sidebar,.bottom-nav,.top-header,.stat-card,.track-card,.lesson-row,.input-field{transition:background-color .2s ease,border-color .2s ease,color .2s ease}
