:root{--bg: #0a0b10;--bg-elevated: #12131a;--surface: #1a1c25;--surface-hover: #22252f;--border: #2a2d3a;--border-light: #353849;--text: #e8eaf0;--text-secondary: #9ca0b4;--text-muted: #6b6f85;--accent: #6366f1;--accent-hover: #818cf8;--accent-dim: rgba(99, 102, 241, .15);--success: #22c55e;--success-dim: rgba(34, 197, 94, .15);--warning: #f59e0b;--warning-dim: rgba(245, 158, 11, .15);--danger: #ef4444;--danger-dim: rgba(239, 68, 68, .12);--radius: 12px;--radius-sm: 8px;--radius-xs: 6px;--radius-lg: 16px;--shadow-sm: 0 2px 8px rgba(0, 0, 0, .2);--shadow-md: 0 8px 24px rgba(0, 0, 0, .3);--shadow-lg: 0 12px 40px rgba(0, 0, 0, .4);--shadow-xl: 0 20px 60px rgba(0, 0, 0, .5);--shadow-accent: 0 4px 20px rgba(99, 102, 241, .2);--accent-gradient: linear-gradient(135deg, #6366f1, #8b5cf6, #a78bfa);--glass-bg: rgba(18, 19, 26, .7);--glass-border: rgba(255, 255, 255, .06);--transition-fast: .15s ease;--transition-normal: .25s ease;--transition-slow: .4s ease}[data-theme=light]{--bg: #f8f9fc;--bg-elevated: #ffffff;--surface: #ffffff;--surface-hover: #f3f4f6;--border: #e5e7eb;--border-light: #d1d5db;--text: #111827;--text-secondary: #4b5563;--text-muted: #9ca3af;--accent: #4f46e5;--accent-hover: #6366f1;--accent-dim: rgba(79, 70, 229, .1);--success: #16a34a;--success-dim: rgba(22, 163, 74, .1);--warning: #d97706;--warning-dim: rgba(217, 119, 6, .1);--danger: #dc2626;--danger-dim: rgba(220, 38, 38, .08);--shadow-sm: 0 1px 3px rgba(0, 0, 0, .08);--shadow-md: 0 4px 16px rgba(0, 0, 0, .08);--shadow-lg: 0 8px 30px rgba(0, 0, 0, .1);--shadow-xl: 0 16px 50px rgba(0, 0, 0, .12);--shadow-accent: 0 4px 20px rgba(79, 70, 229, .15);--accent-gradient: linear-gradient(135deg, #4f46e5, #7c3aed, #8b5cf6);--glass-bg: rgba(255, 255, 255, .7);--glass-border: rgba(0, 0, 0, .06)}[data-theme=light] .gradient-text,[data-theme=light] .catalog-hero h1{background:linear-gradient(135deg,#1e1b4b,#4f46e5,#7c3aed);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}[data-theme=light] .course-card-gradient{background:linear-gradient(135deg,#c7d2fe,#a5b4fc,#818cf8)}[data-theme=light] ::-webkit-scrollbar-thumb{background:#d1d5db}[data-theme=light] ::-webkit-scrollbar-thumb:hover{background:#9ca3af}*{margin:0;padding:0;box-sizing:border-box}body{font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:var(--bg);color:var(--text);line-height:1.6;min-height:100vh;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;transition:background-color .3s ease,color .3s ease}button,a,input,select,textarea,.nav-link,.card,.btn,[class*=toggle],[class*=badge],[class*=tab]{transition:background-color .3s ease,border-color .3s ease,box-shadow .3s ease,color .1s ease}a{color:inherit;text-decoration:none}button{font-family:inherit}::-webkit-scrollbar{width:6px;height:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:3px}::-webkit-scrollbar-thumb:hover{background:var(--border-light)}.gradient-text{background:linear-gradient(135deg,#fff 0%,var(--accent-hover) 50%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.btn-primary{display:inline-flex;align-items:center;gap:8px;padding:10px 22px;background:var(--accent);border:none;border-radius:24px;color:#fff;font-size:.9rem;font-weight:600;cursor:pointer;transition:all var(--transition-fast);font-family:inherit}.btn-primary:hover:not(:disabled){background:var(--accent-hover);transform:translateY(-1px);box-shadow:var(--shadow-accent)}.btn-primary:disabled{opacity:.4;cursor:not-allowed}.btn-primary.btn-sm{padding:7px 16px;font-size:.82rem}.btn-primary.btn-lg{padding:14px 30px;font-size:1rem}.btn-ghost{display:inline-flex;align-items:center;gap:8px;padding:10px 22px;background:transparent;border:1px solid var(--border);border-radius:24px;color:var(--text-secondary);font-size:.9rem;font-weight:500;cursor:pointer;transition:all var(--transition-fast);font-family:inherit}.btn-ghost:hover{background:var(--surface);color:var(--text);border-color:var(--border-light)}.loading-spinner{width:32px;height:32px;border:3px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin .8s linear infinite}.navbar{display:flex;align-items:center;justify-content:space-between;padding:16px 32px;background:var(--bg-elevated);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:100;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px)}.navbar-brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:1.1rem;color:var(--text)}.navbar-brand svg{color:var(--accent)}.navbar-nav{display:flex;align-items:center;gap:6px}.navbar-link{padding:7px 16px;border-radius:20px;font-size:.85rem;font-weight:500;color:var(--text-secondary);transition:all var(--transition-fast);border:1px solid transparent}.navbar-link:hover{color:var(--text);background:var(--surface)}.navbar-link.active{color:var(--accent-hover);background:var(--accent-dim);border-color:#6366f133}.navbar-back{font-size:.85rem;color:var(--text-secondary);padding:6px 16px;border-radius:var(--radius-xs);border:1px solid var(--border);transition:all var(--transition-fast)}.navbar-back:hover{background:var(--surface);color:var(--text);border-color:var(--accent)}.page-container{max-width:1200px;margin:0 auto;padding:40px 32px}.catalog-hero{text-align:center;margin-bottom:48px;padding:48px 0}.catalog-hero p{font-size:1.1rem;color:var(--text-secondary);max-width:600px;margin:0 auto;line-height:1.7}.course-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(380px,1fr));gap:24px}.course-card{position:relative;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;transition:all var(--transition-normal);cursor:pointer}.course-card:hover{border-color:var(--accent);transform:translateY(-4px);box-shadow:0 12px 40px #6366f126}.course-card-gradient{height:140px;background:linear-gradient(135deg,#1e1b4b,#312e81,#4338ca);position:relative}.course-card-gradient:after{content:"";position:absolute;top:0;right:0;bottom:0;left:0;background:linear-gradient(to bottom,transparent 40%,var(--surface))}.course-card-content{padding:0 24px 24px;margin-top:-32px;position:relative}.course-card-badge{display:inline-block;background:var(--accent);color:#fff;font-size:.72rem;font-weight:700;padding:4px 12px;border-radius:20px;letter-spacing:.5px;margin-bottom:12px}.course-card-content h2{font-size:1.4rem;font-weight:700;margin-bottom:4px}.course-card-institution{font-size:.82rem;color:var(--text-muted);margin-bottom:12px}.course-card-desc{font-size:.88rem;color:var(--text-secondary);line-height:1.6;margin-bottom:16px;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}.course-card-meta{display:flex;gap:16px;font-size:.78rem;color:var(--text-muted)}.course-card-meta span{display:flex;align-items:center;gap:5px}.course-header{margin-bottom:40px;padding-bottom:32px;border-bottom:1px solid var(--border)}.course-header-badge{display:inline-block;background:var(--accent-dim);color:var(--accent-hover);font-size:.78rem;font-weight:700;padding:6px 16px;border-radius:20px;margin-bottom:16px}.course-header h1{font-size:2.2rem;font-weight:800;margin-bottom:12px}.course-header-meta{display:flex;gap:24px;margin-bottom:16px;font-size:.88rem;color:var(--text-secondary)}.course-header-meta span{display:flex;align-items:center;gap:6px}.course-header-desc{font-size:1rem;color:var(--text-secondary);max-width:700px;line-height:1.7}.section-title{font-size:1.2rem;font-weight:700;margin-bottom:20px;color:var(--text)}.lecture-list{display:flex;flex-direction:column;gap:12px}.lecture-card{display:flex;align-items:center;gap:20px;padding:20px 24px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);transition:all .2s ease;cursor:pointer}.lecture-card:hover{background:var(--surface-hover);border-color:var(--accent)}.lecture-number{width:48px;height:48px;border-radius:12px;background:var(--accent-dim);display:flex;align-items:center;justify-content:center;flex-shrink:0}.lecture-number span{font-size:1.1rem;font-weight:800;color:var(--accent-hover)}.lecture-info{flex:1;min-width:0}.lecture-info h3{font-size:1rem;font-weight:600;margin-bottom:4px}.lecture-info p{font-size:.82rem;color:var(--text-secondary);line-height:1.5;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.lecture-concepts{display:flex;flex-wrap:wrap;gap:6px;margin-top:8px}.concept-tag{font-size:.7rem;padding:2px 8px;border-radius:12px;background:var(--bg);color:var(--text-muted);border:1px solid var(--border)}.concept-more{color:var(--accent-hover);border-color:var(--accent-dim)}.lecture-action{display:flex;align-items:center;gap:8px;flex-shrink:0}.lecture-play-btn{width:40px;height:40px;border-radius:50%;background:var(--accent);display:flex;align-items:center;justify-content:center;color:#fff;transition:all .2s}.lecture-card:hover .lecture-play-btn{background:var(--accent-hover);transform:scale(1.1)}.lecture-chevron{color:var(--text-muted)}.dashboard-page{max-width:1200px;margin:0 auto;padding:32px 32px 100px;position:relative}.dashboard-hero{display:flex;align-items:center;justify-content:space-between;gap:40px;padding:40px 0 48px}.dashboard-hero-content{flex:1}.dashboard-greeting{font-size:2.4rem;font-weight:800;line-height:1.2;margin-bottom:10px}.dashboard-subtitle{font-size:1.05rem;color:var(--text-secondary);line-height:1.7;max-width:500px;margin-bottom:28px}.dashboard-quick-stats{display:flex;gap:20px}.quick-stat{display:flex;align-items:center;gap:10px;padding:10px 18px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);transition:all var(--transition-fast)}.quick-stat:hover{border-color:var(--border-light);background:var(--surface-hover)}.quick-stat-icon{width:36px;height:36px;border-radius:10px;display:flex;align-items:center;justify-content:center;flex-shrink:0}.quick-stat-icon.independence{background:var(--accent-dim);color:var(--accent-hover)}.quick-stat-icon.mastery{background:var(--success-dim);color:var(--success)}.quick-stat-icon.reviews{background:var(--warning-dim);color:var(--warning)}.quick-stat-info{display:flex;flex-direction:column}.quick-stat-value{font-size:1.1rem;font-weight:700;line-height:1.2}.quick-stat-label{font-size:.72rem;color:var(--text-muted);font-weight:500}.dashboard-mastery-ring{flex-shrink:0}.mastery-ring{position:relative;width:140px;height:140px}.mastery-ring-svg{width:100%;height:100%;transform:rotate(0)}.mastery-ring-progress{transition:stroke-dashoffset 1s ease}.mastery-ring-label{position:absolute;top:0;right:0;bottom:0;left:0;display:flex;flex-direction:column;align-items:center;justify-content:center}.mastery-ring-value{font-size:1.5rem;font-weight:800;line-height:1}.mastery-ring-text{font-size:.72rem;color:var(--text-muted);font-weight:500;margin-top:2px}.dashboard-section{margin-bottom:40px}.dashboard-independence{margin-bottom:32px}.section-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:18px}.section-title-v2{display:flex;align-items:center;gap:10px;font-size:1.15rem;font-weight:700;color:var(--text)}.section-title-v2 svg{color:var(--accent)}.section-action{display:flex;align-items:center;gap:6px;font-size:.82rem;font-weight:500;color:var(--accent-hover);transition:all var(--transition-fast)}.section-action:hover{color:#fff}.continue-card{display:flex;gap:20px;padding:20px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;transition:all 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h3{font-size:1.05rem;font-weight:600}.continue-meta{font-size:.82rem;color:var(--text-secondary)}.review-due-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:10px}.review-due-card{display:flex;align-items:center;gap:12px;padding:12px 16px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-sm);transition:all var(--transition-fast)}.review-due-card:hover{background:var(--surface-hover);border-color:var(--border-light)}.review-due-icon{width:32px;height:32px;border-radius:8px;background:var(--warning-dim);color:var(--warning);display:flex;align-items:center;justify-content:center;flex-shrink:0}.review-due-info{flex:1;min-width:0}.review-due-concept{display:block;font-size:.88rem;font-weight:600;line-height:1.3}.review-due-source{display:block;font-size:.72rem;color:var(--text-muted);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.review-due-strength{font-size:.68rem;font-weight:700;padding:3px 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p{font-size:.9rem;color:var(--text-secondary);margin-bottom:24px;max-width:400px;margin-left:auto;margin-right:auto}.library-grid-preview{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:16px}.upload-fab{position:fixed;bottom:32px;right:32px;width:56px;height:56px;border-radius:50%;background:var(--accent);border:none;color:#fff;display:flex;align-items:center;justify-content:center;cursor:pointer;box-shadow:0 4px 20px #6366f166;transition:all var(--transition-fast);z-index:50}.upload-fab:hover{background:var(--accent-hover);transform:scale(1.1);box-shadow:0 6px 28px #6366f180}.video-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;transition:all var(--transition-normal);cursor:pointer;display:block}.video-card:hover{border-color:var(--accent);transform:translateY(-3px);box-shadow:0 8px 30px #6366f11f}.video-card-thumb{position:relative;width:100%;aspect-ratio:16 / 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10px;border-radius:12px;font-size:.68rem;font-weight:700;background:#f59e0be6;color:#fff}.video-card-body{padding:14px 16px}.video-card-body h3{font-size:.92rem;font-weight:600;line-height:1.3;margin-bottom:8px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.video-card-meta{display:flex;gap:14px;font-size:.72rem;color:var(--text-muted)}.video-card-meta span{display:flex;align-items:center;gap:4px}.video-card-mastery-bar{height:3px;background:var(--border);border-radius:2px;margin-top:10px;overflow:hidden}.video-card-mastery-fill{height:100%;border-radius:2px;background:linear-gradient(90deg,var(--accent),var(--success));transition:width .4s ease}.upload-page{max-width:700px;margin:0 auto;padding:60px 32px 80px;min-height:calc(100vh - 61px);display:flex;flex-direction:column;justify-content:center}.upload-container{text-align:center}.upload-heading{font-size:2rem;font-weight:800;margin-bottom:10px;background:linear-gradient(135deg,#fff,var(--accent-hover));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.upload-subheading{font-size:1rem;color:var(--text-secondary);line-height:1.7;margin-bottom:36px;max-width:500px;margin-left:auto;margin-right:auto}.upload-error{display:flex;align-items:center;gap:10px;padding:12px 16px;background:var(--danger-dim);border:1px solid rgba(239,68,68,.3);border-radius:var(--radius-sm);color:var(--danger);font-size:.88rem;margin-bottom:20px;text-align:left}.upload-error-dismiss{margin-left:auto;background:none;border:none;color:var(--danger);cursor:pointer;padding:2px;flex-shrink:0}.upload-dropzone{padding:60px 40px;border:2px dashed var(--border);border-radius:var(--radius-lg);background:var(--surface);cursor:pointer;transition:all var(--transition-normal);text-align:center}.upload-dropzone:hover{border-color:var(--accent);background:#6366f10a}.upload-dropzone.drag-over{border-color:var(--accent);background:#6366f114;transform:scale(1.02);box-shadow:0 0 40px #6366f126}.dropzone-icon{width:64px;height:64px;margin:0 auto 16px;border-radius:16px;background:var(--accent-dim);color:var(--accent-hover);display:flex;align-items:center;justify-content:center;transition:all var(--transition-normal)}.upload-dropzone:hover .dropzone-icon,.upload-dropzone.drag-over .dropzone-icon{background:#6366f140;transform:scale(1.1)}.upload-dropzone h3{font-size:1.1rem;font-weight:600;margin-bottom:4px}.upload-dropzone p{font-size:.88rem;color:var(--text-secondary);margin-bottom:8px}.dropzone-formats{font-size:.75rem;color:var(--text-muted)}.upload-divider{display:flex;align-items:center;gap:16px;margin:28px 0;color:var(--text-muted);font-size:.82rem;font-weight:500}.upload-divider:before,.upload-divider:after{content:"";flex:1;height:1px;background:var(--border)}.upload-url-form{display:flex;gap:10px;align-items:center}.upload-url-input-wrap{flex:1;position:relative}.upload-url-icon{position:absolute;left:16px;top:50%;transform:translateY(-50%);color:var(--text-muted)}.upload-url-input{width:100%;padding:12px 16px 12px 44px;background:var(--surface);border:1px solid var(--border);border-radius:24px;color:var(--text);font-size:.9rem;font-family:inherit;outline:none;transition:border-color var(--transition-fast)}.upload-url-input:focus{border-color:var(--accent)}.upload-url-input::placeholder{color:var(--text-muted)}.upload-processing{text-align:center}.upload-processing h2{font-size:1.5rem;font-weight:700;margin-bottom:8px}.upload-processing-sub{font-size:.92rem;color:var(--text-secondary);margin-bottom:40px}.upload-stages{display:flex;flex-direction:column;gap:0;max-width:320px;margin:0 auto;text-align:left}.upload-stage{display:flex;align-items:center;gap:14px;padding:14px 0;position:relative}.upload-stage-icon{width:40px;height:40px;border-radius:50%;display:flex;align-items:center;justify-content:center;flex-shrink:0;border:2px solid var(--border);background:var(--surface);color:var(--text-muted);transition:all .3s ease}.upload-stage.done .upload-stage-icon{background:var(--success-dim);border-color:var(--success);color:var(--success)}.upload-stage.active .upload-stage-icon{background:var(--accent-dim);border-color:var(--accent);color:var(--accent-hover);box-shadow:0 0 20px #6366f14d}.upload-stage-label{font-size:.92rem;font-weight:500;color:var(--text-muted);transition:color .3s ease}.upload-stage.done .upload-stage-label{color:var(--success)}.upload-stage.active .upload-stage-label{color:var(--text);font-weight:600}.upload-stage-connector{position:absolute;left:19px;top:54px;width:2px;height:28px;background:var(--border);transition:background .3s 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60%);border-radius:50%}.auth-branding-content{position:relative;z-index:1}.auth-logo{display:flex;align-items:center;justify-content:center;width:64px;height:64px;background:#ffffff1a;border-radius:var(--radius);margin-bottom:32px;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border:1px solid rgba(255,255,255,.1);color:#fff}.auth-branding-title{font-size:2rem;font-weight:800;color:#fff;line-height:1.2;margin-bottom:16px}.auth-branding-title .gradient-text{background:linear-gradient(135deg,#c7d2fe,#a5b4fc,#818cf8);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.auth-branding-subtitle{color:#ffffffb3;font-size:1rem;line-height:1.7;margin-bottom:40px}.auth-branding-features{display:flex;flex-direction:column;gap:14px}.auth-feature{display:flex;align-items:center;gap:12px;color:#ffffffd9;font-size:.92rem}.auth-feature-dot{width:8px;height:8px;border-radius:50%;background:var(--accent-hover);flex-shrink:0}.auth-branding-stats{display:flex;gap:32px;margin-top:40px}.auth-stat{display:flex;flex-direction:column;gap:4px}.auth-stat-value{font-size:1.6rem;font-weight:800;color:#fff}.auth-stat-label{font-size:.82rem;color:#fff9}.auth-branding-footer{position:relative;z-index:1;font-size:.8rem;color:#fff6}.auth-form-panel{display:flex;align-items:center;justify-content:center;padding:48px 40px;overflow-y:auto}.auth-form-wrapper{width:100%;max-width:380px}.auth-form-header{margin-bottom:32px}.auth-form-header h2{font-size:1.6rem;font-weight:800;margin-bottom:8px;line-height:1.2}.auth-form-header p{color:var(--text-secondary);font-size:.95rem}.auth-error{display:flex;align-items:center;gap:10px;padding:12px 16px;background:var(--danger-dim);border:1px solid rgba(239,68,68,.2);border-radius:var(--radius-sm);color:var(--danger);font-size:.87rem;margin-bottom:20px;animation:scaleIn .2s ease}.auth-form{display:flex;flex-direction:column;gap:20px}.auth-field{display:flex;flex-direction:column;gap:6px}.auth-field label{font-size:.85rem;font-weight:600;color:var(--text-secondary)}.auth-input-wrapper{display:flex;align-items:center;gap:10px;padding:0 14px;background:var(--surface);border:1.5px solid var(--border);border-radius:var(--radius-sm);transition:all var(--transition-fast)}.auth-input-wrapper:focus-within{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-dim)}.auth-input-icon{color:var(--text-muted);flex-shrink:0}.auth-input-wrapper input,.auth-input-wrapper select{flex:1;padding:12px 0;background:none;border:none;outline:none;color:var(--text);font-size:.92rem;font-family:inherit}.auth-input-wrapper input::placeholder{color:var(--text-muted)}.auth-input-wrapper select{cursor:pointer;-webkit-appearance:auto;-moz-appearance:auto;appearance:auto}.auth-textarea-wrapper{align-items:flex-start;padding:14px}.auth-textarea-wrapper textarea{flex:1;width:100%;background:none;border:none;outline:none;color:var(--text);font-size:.92rem;font-family:inherit;resize:vertical;min-height:80px}.auth-textarea-wrapper textarea::placeholder{color:var(--text-muted)}.auth-input-toggle{display:flex;align-items:center;justify-content:center;background:none;border:none;color:var(--text-muted);cursor:pointer;padding:4px;border-radius:4px;transition:color var(--transition-fast)}.auth-input-toggle:hover{color:var(--text)}.auth-match-indicator{display:flex;align-items:center;padding:4px}.auth-match-indicator.match{color:var(--success)}.auth-match-indicator.no-match{color:var(--danger)}.auth-options{display:flex;align-items:center;justify-content:space-between;font-size:.85rem}.auth-checkbox-label{display:flex;align-items:flex-start;gap:8px;font-size:.85rem;color:var(--text-secondary);cursor:pointer}.auth-checkbox{width:16px;height:16px;border-radius:4px;accent-color:var(--accent);cursor:pointer;flex-shrink:0;margin-top:2px}.auth-terms{margin-top:4px}.auth-link{color:var(--text-muted);font-size:.85rem;transition:color var(--transition-fast)}.auth-link:hover{color:var(--text)}.auth-link-primary{color:var(--accent);font-weight:600;transition:color var(--transition-fast)}.auth-link-primary:hover{color:var(--accent-hover)}.auth-submit-btn{display:flex;align-items:center;justify-content:center;gap:10px;padding:13px 24px;background:var(--accent-gradient);border:none;border-radius:var(--radius-sm);color:#fff;font-size:.95rem;font-weight:700;cursor:pointer;transition:all var(--transition-fast);font-family:inherit;margin-top:4px}.auth-submit-btn:hover:not(:disabled){transform:translateY(-1px);box-shadow:var(--shadow-accent),0 4px 16px #6366f14d}.auth-submit-btn:active:not(:disabled){transform:translateY(0)}.auth-submit-btn:disabled{opacity:.7;cursor:not-allowed}.auth-divider{display:flex;align-items:center;gap:16px;margin:24px 0}.auth-divider:before,.auth-divider:after{content:"";flex:1;height:1px;background:var(--border)}.auth-divider span{font-size:.82rem;color:var(--text-muted);white-space:nowrap}.auth-demo-buttons{display:flex;gap:10px;margin-bottom:24px}.auth-demo-btn{flex:1;display:flex;align-items:center;justify-content:center;gap:8px;padding:11px 16px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--text-secondary);font-size:.87rem;font-weight:600;cursor:pointer;transition:all var(--transition-fast);font-family:inherit}.auth-demo-btn:hover{background:var(--surface-hover);color:var(--text);border-color:var(--border-light)}.auth-demo-btn-admin{border-color:#6366f133;color:var(--accent)}.auth-demo-btn-admin:hover{background:var(--accent-dim);border-color:#6366f14d}.auth-demo-btn-full{width:100%;margin-bottom:24px}.auth-footer-text{text-align:center;font-size:.9rem;color:var(--text-secondary)}.password-strength{display:flex;align-items:center;gap:10px;margin-top:6px}.password-strength-bar{flex:1;height:4px;background:var(--border);border-radius:2px;overflow:hidden}.password-strength-fill{height:100%;border-radius:2px;transition:all .3s ease}.password-strength-label{font-size:.78rem;font-weight:600;white-space:nowrap}.password-requirements{display:flex;flex-direction:column;gap:4px;margin-top:8px}.password-req{display:flex;align-items:center;gap:6px;font-size:.78rem;color:var(--text-muted);transition:color var(--transition-fast)}.password-req.met{color:var(--success)}@media (max-width: 768px){.auth-container{grid-template-columns:1fr;max-width:480px;min-height:unset}.auth-branding{display:none}.auth-form-panel{padding:40px 24px}}.profile-page{animation:pageSlideUp .35s ease}.profile-header{position:relative;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-lg);overflow:hidden;margin-bottom:32px}.profile-header-bg{height:120px;background:linear-gradient(135deg,#1e1b4b,#312e81,#4338ca,#6366f1);position:relative}.profile-header-bg:after{content:"";position:absolute;top:0;right:0;bottom:0;left:0;background:linear-gradient(to bottom,transparent 40%,var(--surface))}.profile-header-content{display:flex;align-items:flex-start;gap:24px;padding:0 32px 32px;margin-top:-48px;position:relative}.profile-avatar-large{width:96px;height:96px;border-radius:50%;background:var(--accent-gradient);display:flex;align-items:center;justify-content:center;font-size:1.8rem;font-weight:800;color:#fff;border:4px solid var(--surface);flex-shrink:0}.profile-header-info{flex:1;padding-top:20px}.profile-header-info h1{font-size:1.8rem;font-weight:800;line-height:1.2;margin-bottom:8px}.profile-email,.profile-member-since{display:flex;align-items:center;gap:8px;font-size:.87rem;color:var(--text-secondary);margin-bottom:4px}.profile-bio{font-size:.92rem;color:var(--text-secondary);margin-top:8px;line-height:1.6}.profile-header-actions{display:flex;align-items:center;gap:8px;padding-top:24px}.profile-theme-toggle{display:flex;align-items:center;justify-content:center;width:40px;height:40px;border-radius:50%;background:var(--surface-hover);border:1px solid var(--border);color:var(--text-secondary);cursor:pointer;transition:all var(--transition-fast)}.profile-theme-toggle:hover{color:var(--warning);border-color:var(--warning)}.profile-edit-section{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:32px;margin-bottom:32px;animation:scaleIn .2s ease}.profile-edit-section h3{font-size:1.2rem;font-weight:700;margin-bottom:24px}.profile-edit-form{display:flex;flex-direction:column;gap:20px;max-width:500px}.profile-edit-theme{display:flex;flex-direction:column;gap:8px}.profile-edit-theme label{font-size:.85rem;font-weight:600;color:var(--text-secondary)}.profile-theme-switcher{display:flex;gap:8px}.profile-theme-option{display:flex;align-items:center;gap:8px;padding:10px 20px;background:var(--bg);border:1.5px solid var(--border);border-radius:var(--radius-sm);color:var(--text-secondary);font-size:.87rem;font-weight:500;cursor:pointer;transition:all var(--transition-fast);font-family:inherit}.profile-theme-option.active{border-color:var(--accent);background:var(--accent-dim);color:var(--accent)}.profile-section{margin-bottom:32px}.profile-section-title{font-size:1.25rem;font-weight:700;margin-bottom:20px;display:flex;align-items:center;gap:10px}.profile-stats-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:16px}.profile-stat-card{display:flex;align-items:center;gap:16px;padding:20px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);transition:all var(--transition-fast)}.profile-stat-card:hover{border-color:var(--border-light);transform:translateY(-2px);box-shadow:var(--shadow-md)}.profile-stat-icon{width:48px;height:48px;border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center;flex-shrink:0}.profile-stat-info{display:flex;flex-direction:column}.profile-stat-value{font-size:1.4rem;font-weight:800;line-height:1.2}.profile-stat-label{font-size:.8rem;color:var(--text-muted);font-weight:500}.profile-streak-cards{display:grid;grid-template-columns:1fr 1fr;gap:16px}.profile-streak-card{display:flex;align-items:center;gap:20px;padding:28px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);position:relative;overflow:hidden;transition:all var(--transition-fast)}.profile-streak-card:hover{transform:translateY(-2px);box-shadow:var(--shadow-md)}.profile-streak-current{border-color:#f59e0b4d;background:linear-gradient(135deg,var(--surface),rgba(245,158,11,.05))}.profile-streak-longest{border-color:#a855f74d;background:linear-gradient(135deg,var(--surface),rgba(168,85,247,.05))}.profile-streak-flame{color:#f59e0b;animation:pulse 2s ease-in-out infinite}.profile-streak-trophy{color:#a855f7}.profile-streak-info{flex:1}.profile-streak-value{font-size:2.4rem;font-weight:900;line-height:1;display:block}.profile-streak-label{font-size:.85rem;color:var(--text-secondary);margin-top:4px;display:block}.profile-streak-badge{position:absolute;top:12px;right:12px;font-size:.72rem;font-weight:700;padding:3px 10px;border-radius:20px;background:var(--accent-dim);color:var(--accent);text-transform:uppercase;letter-spacing:.5px}.profile-streak-current 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p{font-size:.78rem;color:var(--text-secondary);line-height:1.4}.profile-achievement-date{font-size:.72rem;color:var(--text-muted)}.profile-subscription-card{display:flex;align-items:center;justify-content:space-between;padding:28px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);gap:24px}.profile-subscription-info{flex:1}.profile-subscription-plan{display:flex;align-items:center;gap:16px;margin-bottom:16px}.profile-subscription-plan svg{color:#f59e0b}.profile-subscription-plan h3{font-size:1.2rem;font-weight:700}.profile-subscription-plan p{font-size:.85rem;color:var(--text-secondary)}.profile-subscription-features{display:flex;flex-wrap:wrap;gap:12px}.profile-subscription-features span{font-size:.82rem;padding:4px 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ease;opacity:.7}.admin-bar:hover{opacity:1}.admin-bar-label{position:absolute;bottom:-20px;font-size:.65rem;color:var(--text-muted);white-space:nowrap}.admin-horizontal-chart{display:flex;flex-direction:column;gap:10px}.admin-h-bar-row{display:flex;align-items:center;gap:12px}.admin-h-bar-label{width:160px;font-size:.82rem;color:var(--text-secondary);flex-shrink:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.admin-h-bar-track{flex:1;height:20px;background:var(--bg);border-radius:4px;overflow:hidden}.admin-h-bar{height:100%;background:var(--accent-gradient);border-radius:4px;transition:width .5s ease;opacity:.8}.admin-h-bar-value{font-size:.8rem;font-weight:700;color:var(--text-secondary);min-width:40px;text-align:right}.admin-line-chart{position:relative}.admin-line-svg{width:100%;height:200px}.admin-line-labels{display:flex;justify-content:space-between;margin-top:8px}.admin-line-labels 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var(--border);border-radius:var(--radius);padding:24px}.admin-quick-links-card h3{font-size:1rem;font-weight:700;margin-bottom:16px}.admin-quick-links{display:flex;flex-direction:column;gap:4px}.admin-quick-link{display:flex;align-items:center;gap:12px;padding:14px 16px;border-radius:var(--radius-sm);color:var(--text-secondary);transition:all var(--transition-fast)}.admin-quick-link:hover{background:var(--surface-hover);color:var(--text)}.admin-quick-link span{flex:1;font-size:.9rem;font-weight:500}.admin-quick-link svg:last-child{color:var(--text-muted)}.admin-users-filters{display:flex;align-items:center;gap:12px;margin-bottom:20px}.admin-search-wrapper{flex:1;display:flex;align-items:center;gap:10px;padding:0 14px;background:var(--surface);border:1.5px solid var(--border);border-radius:var(--radius-sm);max-width:400px}.admin-search-wrapper:focus-within{border-color:var(--accent);box-shadow:0 0 0 3px 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