:root{--color-primary: #1B3A5C;--color-primary-hover: #244E78;--color-primary-active: #132940;--color-primary-light: #E8F0FE;--color-primary-dark: #0F1F33;--color-accent: #4ECDC4;--color-accent-hover: #3DBDB5;--color-accent-light: #E6F9F7;--color-warm: #FFB347;--color-warm-hover: #F5A233;--color-warm-light: #FFF3E0;--color-success: #10B981;--color-success-light: #ECFDF5;--color-warning: #F59E0B;--color-warning-light: #FFFBEB;--color-danger: #EF4444;--color-danger-light: #FEF2F2;--color-info: #3B82F6;--color-text-primary: #1E293B;--color-text-secondary: #475569;--color-text-tertiary: #94A3B8;--color-text-disabled: #CBD5E1;--color-border: #E2E8F0;--color-border-light: #F1F5F9;--color-background: #F8FAFC;--color-surface: #FFFFFF;--color-overlay: rgba(0, 0, 0, .5);--font-family: "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;--font-family-mono: "JetBrains Mono", "SF Mono", "Fira Code", monospace;--font-size-h1: 28px;--font-size-h2: 22px;--font-size-h3: 18px;--font-size-h4: 16px;--font-size-body1: 16px;--font-size-body2: 14px;--font-size-body3: 13px;--font-size-caption: 12px;--font-size-small: 11px;--font-size-button: 15px;--font-size-input: 15px;--line-height-h1: 40px;--line-height-h2: 32px;--line-height-h3: 26px;--line-height-h4: 24px;--line-height-body1: 24px;--line-height-body2: 22px;--line-height-body3: 20px;--line-height-caption: 18px;--spacing-1: 4px;--spacing-2: 8px;--spacing-3: 12px;--spacing-4: 16px;--spacing-5: 20px;--spacing-6: 24px;--spacing-7: 32px;--spacing-8: 40px;--spacing-9: 48px;--spacing-10: 64px;--radius-sm: 4px;--radius-md: 8px;--radius-lg: 12px;--radius-xl: 16px;--radius-full: 9999px;--shadow-sm: 0 1px 2px rgba(0, 0, 0, .05);--shadow-md: 0 4px 6px -1px rgba(0, 0, 0, .07);--shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, .08);--shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, .1);--shadow-inner: inset 0 2px 4px rgba(0, 0, 0, .05);--icon-xs: 16px;--icon-sm: 20px;--icon-md: 24px;--icon-lg: 32px;--sidebar-width: 240px;--sidebar-collapsed: 64px;--header-height: 56px;--page-padding: 32px;--page-padding-tablet: 24px;--content-max-width: 1200px;--transition-fast: .15s ease;--transition-normal: .2s ease;--transition-slow: .3s ease}.subject-math{--subject-color: #EF4444}.subject-chinese{--subject-color: #8B5CF6}.subject-english{--subject-color: #3B82F6}.subject-physics{--subject-color: #F59E0B}.subject-chemistry{--subject-color: #10B981}.subject-biology{--subject-color: #06B6D4}.subject-politics{--subject-color: #EC4899}.subject-history{--subject-color: #F97316}.subject-geography{--subject-color: #14B8A6}.h1{font-size:var(--font-size-h1);line-height:var(--line-height-h1);font-weight:700}.h2{font-size:var(--font-size-h2);line-height:var(--line-height-h2);font-weight:600}.h3{font-size:var(--font-size-h3);line-height:var(--line-height-h3);font-weight:600}.h4{font-size:var(--font-size-h4);line-height:var(--line-height-h4);font-weight:600}.body1{font-size:var(--font-size-body1);line-height:var(--line-height-body1);font-weight:400}.body2{font-size:var(--font-size-body2);line-height:var(--line-height-body2);font-weight:400}.caption{font-size:var(--font-size-caption);line-height:var(--line-height-caption);color:var(--color-text-tertiary)}.small{font-size:var(--font-size-small)}.text-secondary{color:var(--color-text-secondary)}.text-tertiary{color:var(--color-text-tertiary)}.text-primary{color:var(--color-text-primary)}.btn{display:inline-flex;align-items:center;justify-content:center;gap:var(--spacing-2);font-family:var(--font-family);font-size:var(--font-size-button);font-weight:500;border:none;border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast);white-space:nowrap;line-height:1}.btn:disabled{opacity:.45;cursor:not-allowed}.btn-lg{height:48px;padding:0 24px;font-size:16px}.btn-md{height:40px;padding:0 20px}.btn-sm{height:32px;padding:0 14px;font-size:13px}.btn-primary{background-color:var(--color-primary);color:#fff}.btn-primary:hover:not(:disabled){background-color:var(--color-primary-hover)}.btn-primary:active:not(:disabled){background-color:var(--color-primary-active)}.btn-secondary{background-color:transparent;color:var(--color-primary);border:1.5px solid var(--color-primary)}.btn-secondary:hover:not(:disabled){background-color:var(--color-primary-light)}.btn-secondary:active:not(:disabled){background-color:#d1e3f8}.btn-text{background-color:transparent;color:var(--color-primary);padding:0 8px}.btn-text:hover:not(:disabled){background-color:var(--color-primary-light)}.btn-icon{background-color:transparent;color:var(--color-text-secondary);padding:0;width:36px;height:36px;border-radius:var(--radius-md)}.btn-icon:hover:not(:disabled){background-color:var(--color-border-light)}.btn-warm{background-color:var(--color-warm);color:#fff}.btn-warm:hover:not(:disabled){background-color:var(--color-warm-hover)}.btn-success{background-color:var(--color-success);color:#fff}.btn-danger{background-color:var(--color-danger);color:#fff}.btn-block{width:100%}.input-wrapper{display:flex;flex-direction:column;gap:var(--spacing-1)}.input-label{font-size:var(--font-size-body3);font-weight:500;color:var(--color-text-secondary)}.input-field{height:42px;padding:0 12px;font-family:var(--font-family);font-size:var(--font-size-input);color:var(--color-text-primary);background-color:var(--color-surface);border:1.5px solid var(--color-border);border-radius:var(--radius-md);outline:none;transition:all var(--transition-fast)}.input-field::placeholder{color:var(--color-text-tertiary)}.input-field:focus{border-color:var(--color-primary);box-shadow:var(--shadow-inner)}.input-field.error{border-color:var(--color-danger)}.input-field.error:focus{box-shadow:0 0 0 3px #ef44441a}.input-field:disabled{background-color:var(--color-border-light);color:var(--color-text-disabled);cursor:not-allowed}.input-error-text{font-size:var(--font-size-caption);color:var(--color-danger)}textarea.input-field{height:auto;padding:12px;min-height:120px;resize:vertical}.card{background-color:var(--color-surface);border-radius:var(--radius-md);box-shadow:var(--shadow-sm);padding:var(--spacing-4);transition:all var(--transition-fast)}.card-hover:hover{box-shadow:var(--shadow-md);transform:translateY(-2px)}.card-clickable{cursor:pointer}.card-subject{border-left:4px solid var(--subject-color, var(--color-primary))}.card-stat{text-align:center;padding:var(--spacing-5)}.card-stat .stat-number{font-size:32px;font-weight:700;color:var(--color-primary)}.card-stat .stat-label{font-size:var(--font-size-caption);color:var(--color-text-tertiary);margin-top:var(--spacing-1)}.tag{display:inline-flex;align-items:center;padding:2px 10px;font-size:var(--font-size-caption);border-radius:var(--radius-sm);background-color:var(--color-primary-light);color:var(--color-primary);height:22px;white-space:nowrap}.tag-success{background-color:var(--color-success-light);color:#065f46}.tag-warning{background-color:var(--color-warning-light);color:#92400e}.tag-danger{background-color:var(--color-danger-light);color:#991b1b}.tag-outline{background:transparent;border:1px solid var(--color-border);color:var(--color-text-secondary)}@keyframes shimmer{0%{background-position:-200% 0}to{background-position:200% 0}}.skeleton{background:linear-gradient(90deg,#e2e8f0 25%,#f8fafc,#e2e8f0 75%);background-size:200% 100%;animation:shimmer 1.5s ease-in-out infinite;border-radius:var(--radius-sm)}.skeleton-text{height:14px;width:100%;margin-bottom:8px}.skeleton-title{height:22px;width:60%;margin-bottom:12px}.skeleton-card{height:100px;border-radius:var(--radius-md)}.skeleton-circle{width:40px;height:40px;border-radius:50%}.skeleton-list-item{height:72px;border-radius:var(--radius-md);margin-bottom:8px}.empty-state{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:var(--spacing-9) var(--spacing-4);text-align:center}.empty-state-icon{font-size:64px;margin-bottom:var(--spacing-4);opacity:.5}.empty-state-title{font-size:var(--font-size-h4);font-weight:600;color:var(--color-text-primary);margin-bottom:var(--spacing-2)}.empty-state-desc{font-size:var(--font-size-body2);color:var(--color-text-tertiary);margin-bottom:var(--spacing-6)}.toast{position:fixed;top:80px;left:50%;transform:translate(-50%);display:inline-flex;align-items:center;gap:var(--spacing-2);padding:12px 20px;background-color:var(--color-text-primary);color:#fff;font-size:var(--font-size-body2);border-radius:var(--radius-md);box-shadow:var(--shadow-lg);z-index:9999;animation:toastIn .3s ease,toastOut .3s ease 2.7s forwards}@keyframes toastIn{0%{opacity:0;transform:translate(-50%) translateY(-20px)}to{opacity:1;transform:translate(-50%) translateY(0)}}@keyframes toastOut{0%{opacity:1}to{opacity:0;transform:translate(-50%) translateY(-20px)}}.toast-success{border-left:4px solid var(--color-success)}.toast-error{border-left:4px solid var(--color-danger)}.toast-warning{border-left:4px solid var(--color-warning)}.toast-info{border-left:4px solid var(--color-info)}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background-color:var(--color-overlay);display:flex;align-items:center;justify-content:center;z-index:8000;animation:fadeIn .2s ease}.modal-content{background:var(--color-surface);border-radius:var(--radius-lg);width:480px;max-width:90vw;max-height:85vh;overflow-y:auto;box-shadow:var(--shadow-xl);animation:scaleIn .2s ease}.modal-header{display:flex;align-items:center;justify-content:space-between;padding:24px 24px 0}.modal-title{font-size:var(--font-size-h3);font-weight:600}.modal-body{padding:20px 24px}.modal-footer{display:flex;justify-content:flex-end;gap:var(--spacing-3);padding:16px 24px}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes scaleIn{0%{opacity:0;transform:scale(.95)}to{opacity:1;transform:scale(1)}}.sidebar{position:fixed;left:0;top:0;bottom:0;width:var(--sidebar-width);background-color:var(--color-primary);color:#fff;z-index:100;overflow-y:auto}.sidebar-logo{height:var(--header-height);display:flex;align-items:center;padding:0 20px;font-size:20px;font-weight:700;border-bottom:1px solid rgba(255,255,255,.1)}.sidebar-logo .logo-dot{display:inline-block;width:8px;height:8px;border-radius:50%;background-color:var(--color-accent);margin-right:8px}.sidebar-nav{padding:var(--spacing-4) 0}.sidebar-nav-item{display:flex;align-items:center;gap:var(--spacing-3);padding:12px 20px;color:#ffffffb3;cursor:pointer;transition:all var(--transition-fast);font-size:var(--font-size-body2);position:relative}.sidebar-nav-item:hover{color:#fff;background-color:#ffffff14}.sidebar-nav-item.active{color:#fff}.sidebar-nav-item.active:before{content:"";position:absolute;left:0;top:4px;bottom:4px;width:3px;background-color:var(--color-accent);border-radius:0 2px 2px 0}.sidebar-nav-item .nav-icon{width:20px;text-align:center;font-size:18px}.sidebar-section-label{padding:12px 20px 4px;font-size:var(--font-size-small);color:#fff6;text-transform:uppercase;letter-spacing:.5px}.page-header{height:var(--header-height);display:flex;align-items:center;justify-content:space-between;padding:0 var(--page-padding);background-color:var(--color-surface);border-bottom:1px solid var(--color-border)}.page-header-left,.page-header-right{display:flex;align-items:center;gap:var(--spacing-3)}.breadcrumb{display:flex;align-items:center;gap:var(--spacing-1);font-size:var(--font-size-body3);color:var(--color-text-tertiary)}.breadcrumb a{color:var(--color-text-tertiary)}.breadcrumb a:hover{color:var(--color-primary)}.breadcrumb-sep{margin:0 2px}.list-item{display:flex;align-items:center;padding:var(--spacing-4);background:var(--color-surface);border-bottom:1px solid var(--color-border-light);transition:background var(--transition-fast);cursor:pointer}.list-item:hover{background-color:var(--color-background)}.list-item-content{flex:1;min-width:0}.list-item-title{font-size:var(--font-size-body2);font-weight:500;color:var(--color-text-primary);margin-bottom:2px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.list-item-meta{font-size:var(--font-size-caption);color:var(--color-text-tertiary);display:flex;align-items:center;gap:var(--spacing-2);flex-wrap:wrap}.list-item-right{flex-shrink:0;margin-left:var(--spacing-3)}.switch{position:relative;display:inline-block;width:44px;height:24px;cursor:pointer}.switch input{opacity:0;width:0;height:0}.switch-slider{position:absolute;top:0;right:0;bottom:0;left:0;background-color:var(--color-border);border-radius:12px;transition:all var(--transition-normal)}.switch-slider:before{content:"";position:absolute;width:20px;height:20px;left:2px;bottom:2px;background-color:#fff;border-radius:50%;transition:all var(--transition-normal);box-shadow:0 1px 3px #0003}.switch input:checked+.switch-slider{background-color:var(--color-accent)}.switch input:checked+.switch-slider:before{transform:translate(20px)}.checkbox{display:inline-flex;align-items:center;gap:var(--spacing-2);cursor:pointer;font-size:var(--font-size-body2)}.checkbox-input{width:18px;height:18px;border:2px solid var(--color-border);border-radius:4px;cursor:pointer;accent-color:var(--color-primary)}.divider{height:1px;background-color:var(--color-border-light);margin:var(--spacing-4) 0}.divider-vertical{width:1px;background-color:var(--color-border);align-self:stretch}.layout-page{margin-left:var(--sidebar-width);min-height:100vh}.layout-content{padding:var(--page-padding);max-width:var(--content-max-width)}.flex{display:flex}.flex-col{flex-direction:column}.items-center{align-items:center}.justify-between{justify-content:space-between}.justify-center{justify-content:center}.gap-1{gap:var(--spacing-1)}.gap-2{gap:var(--spacing-2)}.gap-3{gap:var(--spacing-3)}.gap-4{gap:var(--spacing-4)}.gap-5{gap:var(--spacing-5)}.gap-6{gap:var(--spacing-6)}.mt-1{margin-top:var(--spacing-1)}.mt-2{margin-top:var(--spacing-2)}.mt-3{margin-top:var(--spacing-3)}.mt-4{margin-top:var(--spacing-4)}.mt-6{margin-top:var(--spacing-6)}.mt-8{margin-top:var(--spacing-8)}.mb-2{margin-bottom:var(--spacing-2)}.mb-4{margin-bottom:var(--spacing-4)}.p-4{padding:var(--spacing-4)}.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:var(--spacing-4)}.grid-4{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--spacing-4)}.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:var(--spacing-4)}.phone-frame{width:375px;height:812px;background:var(--color-background);border-radius:40px;box-shadow:0 0 0 8px #1a1a1a,0 0 0 10px #333,var(--shadow-xl);overflow:hidden;position:relative;margin:20px auto;display:flex;flex-direction:column}.phone-notch{height:44px;background:var(--color-surface);display:flex;align-items:center;justify-content:center;font-size:14px;font-weight:600;position:relative}.phone-notch:after{content:"";position:absolute;top:12px;width:120px;height:24px;background:#1a1a1a;border-radius:12px}.phone-status-bar{height:20px;background:var(--color-surface);display:flex;justify-content:space-between;padding:0 24px;font-size:11px;color:var(--color-text-primary)}.phone-content{flex:1;overflow-y:auto;padding:12px 16px}.phone-tab-bar{height:56px;background:var(--color-surface);border-top:1px solid var(--color-border);display:flex;align-items:center;justify-content:space-around;padding-bottom:env(safe-area-inset-bottom,0)}.phone-tab-item{display:flex;flex-direction:column;align-items:center;gap:2px;font-size:11px;color:var(--color-text-tertiary);cursor:pointer}.phone-tab-item.active{color:var(--color-primary)}.phone-tab-item .tab-icon{font-size:22px}.text-center{text-align:center}.text-right{text-align:right}.truncate{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.avatar{width:40px;height:40px;border-radius:50%;background-color:var(--color-primary);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:600;font-size:16px;flex-shrink:0;overflow:hidden}.avatar-sm{width:28px;height:28px;font-size:12px}.avatar-lg{width:64px;height:64px;font-size:24px}.badge{display:inline-flex;align-items:center;justify-content:center;min-width:18px;height:18px;padding:0 5px;border-radius:var(--radius-full);background-color:var(--color-danger);color:#fff;font-size:11px;font-weight:600}.badge-dot{width:8px;height:8px;border-radius:50%;background-color:var(--color-danger)}*,*:before,*:after{margin:0;padding:0;box-sizing:border-box}html{font-size:16px;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}body{font-family:var(--font-family);color:var(--color-text-primary);background-color:var(--color-background);line-height:1.5}a{color:var(--color-primary);text-decoration:none}a:hover{color:var(--color-primary-hover)}img{max-width:100%;display:block}::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background-color:var(--color-border);border-radius:3px}::-webkit-scrollbar-thumb:hover{background-color:var(--color-text-tertiary)}