:root{--bg-main:#f8fafc;--card-border:#e2e8f0;--text-primary:#0f172a;--text-secondary:#475569;--text-muted:#94a3b8;--accent:#0d9488;--accent-dark:#0f766e;--accent-soft:#ccfbf1}*{box-sizing:border-box;margin:0;padding:0}body{background:var(--bg-main);color:var(--text-primary);min-height:100vh;font-family:Plus Jakarta Sans,system-ui,-apple-system,sans-serif}button,input{font:inherit}.loading{text-align:center;color:var(--text-secondary);padding:48px}.login-page{justify-content:center;align-items:center;min-height:100vh;padding:16px;display:flex}.login-card{border:1px solid var(--card-border);background:#fff;border-radius:16px;flex-direction:column;gap:10px;width:100%;max-width:400px;padding:28px;display:flex;box-shadow:0 1px 2px #0f172a0a}.login-card h1{font-size:20px;font-weight:800}.login-brand{color:var(--accent);align-items:center;gap:12px;margin-bottom:8px;display:flex}.login-brand h1{color:var(--text-primary)}.login-brand p,.login-hint{color:var(--text-secondary);font-size:13px;line-height:1.5}.login-card label{color:var(--text-secondary);font-size:13px;font-weight:600}.login-card input{border:1px solid var(--card-border);border-radius:10px;height:40px;padding:0 12px}.login-card input:focus{outline:2px solid var(--accent-soft);border-color:var(--accent)}.form-error{color:#be123c;font-size:13px}.btn-primary,.btn-secondary{cursor:pointer;white-space:nowrap;border-radius:10px;justify-content:center;align-items:center;gap:6px;height:40px;padding:0 16px;font-size:14px;font-weight:700;text-decoration:none;display:inline-flex}.btn-primary{background:var(--accent);color:#fff;border:none}.btn-primary:hover{background:var(--accent-dark)}.btn-primary:disabled{opacity:.6;cursor:default}.btn-secondary{color:var(--text-primary);border:1px solid var(--card-border);background:#fff}.shell{min-height:100vh;display:flex}.sidebar{border-right:1px solid var(--card-border);background:#fff;flex-direction:column;flex-shrink:0;width:240px;display:flex}.sidebar-brand{box-sizing:border-box;border-bottom:1px solid var(--card-border);height:64px;color:var(--accent);align-items:center;gap:10px;padding:0 18px;font-weight:800;display:flex}.sidebar-brand span{color:var(--text-primary);flex:1}.sidebar nav{flex-direction:column;gap:4px;padding:12px;display:flex}.nav-item{height:40px;color:var(--text-secondary);cursor:pointer;text-align:left;background:0 0;border:none;border-radius:10px;align-items:center;gap:10px;padding:0 12px;font-size:14px;font-weight:600;display:flex}.nav-item:hover{color:var(--text-primary);background:#f1f5f9}.nav-item.active{background:var(--accent-soft);color:var(--accent-dark)}.main{flex-direction:column;flex:1;min-width:0;display:flex}.topbar{box-sizing:border-box;background:#fff;border-bottom:1px solid #e2e8f0;align-items:center;gap:12px;height:64px;padding:0 20px;display:flex}.topbar h1{white-space:nowrap;text-overflow:ellipsis;flex:1;min-width:0;font-size:18px;font-weight:800;overflow:hidden}.topbar-user{align-items:center;gap:8px;font-size:13px;display:flex}.user-name{white-space:nowrap;text-overflow:ellipsis;max-width:180px;font-weight:700;overflow:hidden}.user-role{color:var(--text-muted)}.icon-btn{border:1px solid var(--card-border);width:36px;height:36px;color:var(--text-secondary);cursor:pointer;background:#fff;border-radius:10px;justify-content:center;align-items:center;display:inline-flex}.nav-open,.nav-close{display:none}.workspace{flex:1;padding:24px}.page-card{border:1px solid var(--card-border);background:#fff;border-radius:16px;flex-direction:column;align-items:flex-start;gap:8px;max-width:560px;padding:28px;display:flex}.page-card h2{font-size:18px;font-weight:800}.page-card p{color:var(--text-secondary);font-size:14px;line-height:1.5}.page-icon{background:var(--accent-soft);width:48px;height:48px;color:var(--accent-dark);border-radius:12px;justify-content:center;align-items:center;display:flex}.badge{color:#92400e;background:#fef3c7;border-radius:999px;padding:2px 10px;font-size:12px;font-weight:700}@media (width<=768px){.sidebar{z-index:20;transition:transform .2s;position:fixed;inset:0 auto 0 0;transform:translate(-100%)}.sidebar.open{transform:none;box-shadow:0 0 24px #0f172a26}.nav-open,.nav-close{display:inline-flex}.topbar{padding:0 12px}.user-name,.user-role{display:none}.workspace{padding:16px}}.error-alert{color:#be123c;background:#fff1f2;border:1px solid #fecdd3;border-radius:12px;justify-content:space-between;align-items:center;gap:12px;padding:16px 20px;font-size:14px;font-weight:600;display:flex}.empty-classes-card{border:1px solid var(--card-border);text-align:center;color:var(--text-secondary);background:#fff;border-radius:16px;flex-direction:column;justify-content:center;align-items:center;gap:12px;padding:48px 24px;display:flex}.empty-classes-card .empty-icon{color:var(--accent);opacity:.8}.classes-page-container{flex-direction:column;gap:16px;max-width:960px;display:flex}.classes-list-header{justify-content:space-between;align-items:center;display:flex}.classes-total-count{color:var(--text-secondary);font-size:13px;font-weight:700}.classes-list{flex-direction:column;gap:12px;display:flex}.class-card-btn{border:1px solid var(--card-border);cursor:pointer;text-align:left;width:100%;color:inherit;background:#fff;border-radius:12px;flex-direction:row;justify-content:space-between;align-items:center;gap:16px;padding:16px 20px;font-family:inherit;transition:all .15s;display:flex}.class-card-btn:hover{border-color:var(--accent);box-shadow:0 2px 10px #0d948814}.class-card-main{flex-direction:column;flex:1;gap:8px;min-width:0;display:flex}.class-card-title-row{flex-wrap:wrap;align-items:center;gap:10px;display:flex}.class-card-title{color:var(--text-primary);font-size:16px;font-weight:800}.class-card-schedule{color:var(--text-secondary);align-items:center;gap:6px;font-size:13px;display:inline-flex}.class-card-action{color:var(--text-muted);flex-shrink:0;align-items:center;gap:6px;font-size:13px;font-weight:600;display:flex}.class-card-btn:hover .class-card-action{color:var(--accent)}.status-badge{border-radius:999px;align-items:center;padding:2px 10px;font-size:12px;font-weight:700;display:inline-flex}.status-badge.status-active{color:#047857;background:#ecfdf5;border:1px solid #a7f3d0}.status-badge.status-draft{color:#a16207;background:#fefce8;border:1px solid #fef08a}.status-badge.status-archived{color:#64748b;background:#f1f5f9;border:1px solid #e2e8f0}.grade-pill{color:#166534;background:#f0fdf4;border:1px solid #bbf7d0;border-radius:6px;padding:2px 8px;font-size:12px;font-weight:600}.status-badge-inactive{color:#be123c;background:#fff1f2;border:1px solid #fecdd3;border-radius:999px;padding:2px 8px;font-size:11px;font-weight:700}.class-detail-container{flex-direction:column;gap:20px;max-width:1080px;display:flex}.class-detail-header{flex-direction:column;gap:12px;display:flex}.btn-back{color:var(--accent);cursor:pointer;background:0 0;border:none;align-items:center;gap:6px;width:fit-content;padding:0;font-size:14px;font-weight:700;display:inline-flex}.btn-back:hover{color:var(--accent-dark)}.class-detail-headline{border:1px solid var(--card-border);background:#fff;border-radius:12px;flex-direction:column;gap:10px;padding:20px;display:flex}.class-title-row{flex-wrap:wrap;align-items:center;gap:12px;display:flex}.class-title-row h2{color:var(--text-primary);font-size:22px;font-weight:800}.schedule-meta{color:var(--text-secondary);align-items:center;gap:8px;font-size:14px;display:inline-flex}.class-detail-grid{grid-template-columns:repeat(auto-fit,minmax(300px,1fr));align-items:start;gap:20px;display:grid}.detail-section{border:1px solid var(--card-border);background:#fff;border-radius:12px;flex-direction:column;gap:14px;padding:20px;display:flex}.section-title-wrap{border-bottom:1px solid #f1f5f9;justify-content:space-between;align-items:center;padding-bottom:12px;display:flex}.section-title-left{color:var(--accent);align-items:center;gap:8px;display:flex}.section-title-left h3{color:var(--text-primary);font-size:16px;font-weight:800}.learner-count-stat{color:var(--text-secondary);font-size:13px;font-weight:700}.section-count-badge{color:var(--text-muted);background:#f1f5f9;border-radius:999px;padding:2px 8px;font-size:12px;font-weight:600}.empty-section-text{color:var(--text-muted);padding:12px 0;font-size:13px;font-style:italic}.learner-list,.session-list,.assignment-list{flex-direction:column;gap:8px;margin:0;padding:0;list-style:none;display:flex}.learner-item,.session-item,.assignment-item{background:#f8fafc;border:1px solid #f1f5f9;border-radius:8px;justify-content:space-between;align-items:center;gap:12px;padding:10px 14px;display:flex}.learner-info,.session-info,.assignment-info{flex-direction:column;gap:2px;min-width:0;display:flex}.learner-name,.session-title,.assignment-title{color:var(--text-primary);font-size:14px;font-weight:700}.learner-sub{color:var(--text-muted);font-size:12px}.session-time,.assignment-due{color:var(--text-secondary);font-size:12px}.assignment-progress{color:var(--accent-dark);background:var(--accent-soft);white-space:nowrap;border-radius:6px;padding:2px 8px;font-size:12px;font-weight:700}@media (width<=640px){.class-card-btn{flex-direction:column;align-items:flex-start;gap:10px;padding:14px 16px}.class-card-action{border-top:1px solid #f1f5f9;justify-content:flex-end;width:100%;padding-top:6px}.class-detail-grid{grid-template-columns:1fr}}.assign-page-container{flex-direction:column;gap:20px;max-width:840px;display:flex}.assign-stepper{border:1px solid var(--card-border);background:#fff;border-radius:12px;justify-content:space-between;align-items:center;padding:14px 24px;display:flex}.step-item{color:var(--text-muted);align-items:center;gap:8px;font-size:13px;font-weight:700;display:flex}.step-item.active{color:var(--accent-dark)}.step-item.completed{color:var(--accent)}.step-num{width:24px;height:24px;color:var(--text-secondary);background:#f1f5f9;border-radius:50%;justify-content:center;align-items:center;font-size:12px;font-weight:800;display:flex}.step-item.active .step-num{background:var(--accent);color:#fff}.step-item.completed .step-num{background:var(--accent-soft);color:var(--accent-dark)}.step-divider{background:#f1f5f9;flex:1;height:2px;margin:0 16px}.assign-card{border:1px solid var(--card-border);background:#fff;border-radius:16px;flex-direction:column;gap:20px;padding:24px;display:flex}.assign-card h2{color:var(--text-primary);font-size:18px;font-weight:800}.type-toggle-group{background:#f1f5f9;border-radius:10px;gap:6px;width:fit-content;padding:4px;display:inline-flex}.btn-toggle{color:var(--text-secondary);cursor:pointer;background:0 0;border:none;border-radius:8px;align-items:center;gap:6px;padding:8px 16px;font-size:13px;font-weight:700;transition:all .15s;display:inline-flex}.btn-toggle:hover{color:var(--text-primary)}.btn-toggle.active{color:var(--accent-dark);background:#fff;box-shadow:0 1px 3px #0f172a14}.search-box{flex-direction:column;gap:6px;display:flex}.search-label{color:var(--text-secondary);align-items:center;gap:6px;font-size:13px;font-weight:700;display:flex}.search-input{border:1px solid var(--card-border);height:42px;color:var(--text-primary);border-radius:10px;padding:0 14px;font-size:14px}.search-input:focus{outline:2px solid var(--accent-soft);border-color:var(--accent)}.worksheet-grid{grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:12px;display:grid}.worksheet-card-btn{border:1px solid var(--card-border);text-align:left;cursor:pointer;color:inherit;background:#fff;border-radius:12px;flex-direction:column;gap:8px;padding:14px;font-family:inherit;transition:all .15s;display:flex}.worksheet-card-btn:hover{border-color:var(--accent);box-shadow:0 2px 8px #0d948814}.worksheet-card-btn.selected{border-color:var(--accent);background:var(--accent-soft);box-shadow:0 0 0 2px var(--accent)}.worksheet-title{color:var(--text-primary);font-size:14px;font-weight:700}.worksheet-meta-tags{flex-wrap:wrap;gap:4px;display:flex}.meta-badge{color:var(--text-secondary);background:#f1f5f9;border-radius:4px;padding:2px 6px;font-size:11px;font-weight:600}.worksheet-card-btn.selected .meta-badge{color:var(--accent-dark);background:#fff}.selected-indicator{color:var(--accent-dark);background:var(--accent-soft);border:1px solid #a7f3d0;border-radius:8px;padding:10px 14px;font-size:13px;font-weight:700}.classes-grid{flex-direction:column;gap:10px;display:flex}.class-card-btn.selected{border-color:var(--accent);background:var(--accent-soft);box-shadow:0 0 0 2px var(--accent)}.session-select-wrap{border-top:1px solid #f1f5f9;flex-direction:column;gap:8px;margin-top:10px;padding-top:16px;display:flex}.form-select{border:1px solid var(--card-border);height:42px;color:var(--text-primary);background:#fff;border-radius:10px;padding:0 12px;font-size:14px}.form-select:focus{outline:2px solid var(--accent-soft);border-color:var(--accent)}.assign-form{flex-direction:column;gap:16px;display:flex}.form-group{flex-direction:column;gap:6px;display:flex}.form-label{color:var(--text-secondary);font-size:13px;font-weight:700}.form-input{border:1px solid var(--card-border);height:42px;color:var(--text-primary);border-radius:10px;padding:0 14px;font-size:14px}.form-input:focus{outline:2px solid var(--accent-soft);border-color:var(--accent)}.form-textarea{border:1px solid var(--card-border);color:var(--text-primary);resize:vertical;border-radius:10px;padding:12px 14px;font-family:inherit;font-size:14px}.form-textarea:focus{outline:2px solid var(--accent-soft);border-color:var(--accent)}.step-actions{border-top:1px solid #f1f5f9;justify-content:space-between;align-items:center;gap:12px;padding-top:16px;display:flex}.step-actions .btn-primary:only-child{margin-left:auto}.assign-success-card{text-align:center;align-items:center;gap:16px;padding:48px 24px}.success-icon{color:#059669}.success-text{color:var(--text-primary);max-width:500px;font-size:16px;font-weight:700;line-height:1.5}@media (width<=640px){.assign-stepper{padding:10px 14px}.step-label{display:none}.worksheet-grid{grid-template-columns:1fr}}