:root{--color-bg:#f5f7fa;--color-surface:#fff;--color-border:#e2e8f0;--color-text:#1a202c;--color-muted:#64748b;--color-primary:#2563eb;--color-primary-dark:#1d4ed8;--color-danger:#dc2626;--color-success:#16a34a;--radius:8px;--shadow:0 1px 2px rgba(0,0,0,.06),0 1px 3px rgba(0,0,0,.08)}*{box-sizing:border-box}body,html{padding:0;margin:0}body{background:var(--color-bg);color:var(--color-text);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif}a{color:inherit;text-decoration:none}.app-shell{display:flex;min-height:100vh}.sidebar{width:240px;background:#111827;color:#e5e7eb;padding:16px 0;flex-shrink:0}.sidebar-brand{padding:0 20px 16px;font-weight:700;font-size:18px;color:#fff;border-bottom:1px solid #1f2937;margin-bottom:8px}.sidebar-link{display:block;padding:10px 20px;color:#cbd5e1;font-size:14px;cursor:pointer}.sidebar-link.active,.sidebar-link:hover{background:#1f2937;color:#fff}.sidebar-user{padding:12px 20px;border-top:1px solid #1f2937;margin-top:8px;font-size:13px;color:#94a3b8}.academic-year-switcher{padding:0 20px 16px;border-bottom:1px solid #1f2937;margin-bottom:8px}.academic-year-switcher label{display:block;font-size:11px;text-transform:uppercase;letter-spacing:.04em;color:#64748b;margin-bottom:4px}.academic-year-switcher select{width:100%;padding:6px 8px;border-radius:6px;font-size:13px;font-family:inherit;background:#1f2937;color:#e5e7eb;border:1px solid #374151}.main-content{flex:1 1;padding:24px 32px;max-width:1200px}.page-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px}.page-title{font-size:22px;font-weight:700;margin:0}.card{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px;margin-bottom:20px}table.data-table{width:100%;border-collapse:collapse;font-size:14px}table.data-table th{text-align:left;padding:10px 12px;background:#f8fafc;border-bottom:2px solid var(--color-border);font-weight:600;color:var(--color-muted)}table.data-table td{padding:10px 12px;border-bottom:1px solid var(--color-border)}table.data-table tr:hover td{background:#fafbfc}table.data-table tr.row-tint-a td{background:#fff}table.data-table tr.row-tint-b td{background:#f4f7fb}table.data-table tr.row-tint-a:hover td{background:#fafbfc}table.data-table tr.row-tint-b:hover td{background:#eef2f7}table.data-table tfoot td{padding:10px 12px;border-bottom:none;background:#f8fafc}table.data-table tfoot td,table.data-table tr.row-subtotal td{border-top:2px solid var(--color-border);font-weight:700}table.data-table td input,table.data-table td select{padding:6px 8px;border:1px solid var(--color-border);border-radius:6px;font-size:14px;font-family:inherit;width:100%}.btn{display:inline-flex;align-items:center;gap:6px;padding:8px 14px;border-radius:6px;border:1px solid transparent;font-size:14px;font-weight:600;cursor:pointer}.btn-primary{background:var(--color-primary);color:#fff}.btn-primary:hover{background:var(--color-primary-dark)}.btn-secondary{background:#fff;border-color:var(--color-border);color:var(--color-text)}.btn-secondary:hover{background:#f8fafc}.btn-danger{background:var(--color-danger);color:#fff}.btn:disabled{opacity:.6;cursor:not-allowed}.btn-icon{display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;padding:0;border-radius:6px;border:1px solid var(--color-border);background:#fff;color:var(--color-text);cursor:pointer}.btn-icon:hover{background:#f8fafc;border-color:var(--color-primary);color:var(--color-primary)}.btn-icon-danger:hover{background:#fef2f2;border-color:var(--color-danger);color:var(--color-danger)}.back-link{display:inline-flex;align-items:center;gap:6px;font-size:14px;color:var(--color-muted);margin-bottom:12px}.back-link:hover{color:var(--color-primary)}.form-field{margin-bottom:14px;display:flex;flex-direction:column;gap:4px}.form-field label{font-size:13px;font-weight:600;color:var(--color-muted)}.form-field input,.form-field select,.form-field textarea{padding:8px 10px;border:1px solid var(--color-border);border-radius:6px;font-size:14px;font-family:inherit}.form-grid-2col{display:grid;grid-template-columns:1fr 1fr;grid-gap:0 20px;gap:0 20px}.form-grid-2col .form-field-full{grid-column:1/-1}.modal-overlay{position:fixed;inset:0;background:rgba(15,23,42,.5);display:flex;align-items:center;justify-content:center;z-index:50}.modal-panel{background:#fff;border-radius:10px;padding:24px;width:480px;max-width:92vw;max-height:88vh;overflow-y:auto}.modal-title{font-size:18px;font-weight:700;margin:0 0 16px}.modal-actions{display:flex;justify-content:flex-end;gap:8px;margin-top:20px}.badge{display:inline-block;padding:2px 8px;border-radius:999px;font-size:12px;font-weight:600}.badge-success{background:#dcfce7;color:#166534}.badge-warning{background:#fef9c3;color:#854d0e}.badge-danger{background:#fee2e2;color:#991b1b}.badge-muted{background:#e2e8f0;color:#475569}.login-page{min-height:100vh;display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#1d4ed8,#111827)}.toggle-switch{position:relative;display:inline-block;width:34px;height:19px;flex-shrink:0}.toggle-switch input{opacity:0;width:0;height:0}.toggle-slider{position:absolute;inset:0;background-color:#cbd5e1;transition:.15s;border-radius:999px;cursor:pointer}.toggle-slider:before{content:"";position:absolute;height:13px;width:13px;left:3px;bottom:3px;background-color:#fff;transition:.15s;border-radius:50%}.toggle-switch input:checked+.toggle-slider{background-color:var(--color-primary)}.toggle-switch input:checked+.toggle-slider:before{transform:translateX(15px)}.toggle-switch input:disabled+.toggle-slider{opacity:.6;cursor:not-allowed}.timetable-layout{display:flex;gap:16px;align-items:flex-start}.timetable-class-list{min-width:240px;flex-shrink:0;padding:0;overflow:hidden}.timetable-class-list table.data-table tr{cursor:pointer}.timetable-class-list table.data-table tr.active td{background:#eff6ff;color:var(--color-primary);font-weight:700}.timetable-grid-wrap{flex:1 1;min-width:0;overflow-x:auto}table.timetable-grid{width:100%;border-collapse:collapse;min-width:760px;font-size:14px}table.timetable-grid td,table.timetable-grid th{border:1px solid var(--color-border);padding:10px 12px;text-align:left;vertical-align:top}table.timetable-grid th{background:#f8fafc}.timetable-day-header{display:flex;flex-direction:column;align-items:flex-start;gap:6px;font-weight:600}.timetable-day-header-top{display:flex;align-items:center;gap:8px}.timetable-period-label{font-weight:600}.timetable-period-time{font-size:12px;color:var(--color-muted);margin-top:2px}.timetable-cell,.timetable-cell-empty{width:100%;text-align:left;background:none;border:none;padding:6px;cursor:pointer;border-radius:6px;font-family:inherit}.timetable-cell-empty:hover,.timetable-cell:hover{background:#f1f5f9}.timetable-cell-subject{font-weight:600}.timetable-cell-teacher{font-size:12px;color:var(--color-muted);margin-top:2px}.timetable-cell-empty{color:var(--color-primary);font-weight:600;font-size:13px}.timetable-cell-off{color:var(--color-muted)}.login-card{background:#fff;padding:36px;border-radius:12px;width:380px;max-width:92vw;box-shadow:0 20px 40px rgba(0,0,0,.25)}.error-text{color:var(--color-danger);font-size:13px;margin-top:8px}.required-mark{color:var(--color-danger);margin-left:2px}.empty-state{color:var(--color-muted);padding:24px;text-align:center;font-size:14px}.toolbar{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-bottom:16px}.link-button{display:inline-flex;align-items:center;gap:6px;background:none;border:none;padding:0;color:var(--color-primary);font-weight:600;font-size:14px;font-family:inherit;cursor:pointer}.link-button:hover{text-decoration:underline}.link-button:disabled{opacity:.6;cursor:not-allowed;text-decoration:none}.search-input-wrap{position:relative;margin-bottom:16px}.search-input-wrap .search-input-icon{position:absolute;left:12px;top:50%;transform:translateY(-50%);color:var(--color-muted);pointer-events:none}.search-input-wrap input{width:100%;padding:10px 12px 10px 36px;border:1px solid var(--color-border);border-radius:8px;font-size:14px;font-family:inherit}.combobox,.combobox-input-wrap{position:relative}.combobox-input-wrap input{width:100%;padding:8px 30px 8px 10px;border:1px solid var(--color-border);border-radius:6px;font-size:14px;font-family:inherit}.combobox-clear{position:absolute;right:6px;top:50%;transform:translateY(-50%);background:none;border:none;color:var(--color-muted);font-size:16px;line-height:1;cursor:pointer;padding:4px}.combobox-clear:hover{color:var(--color-danger)}.combobox-menu{position:absolute;z-index:30;top:calc(100% + 4px);left:0;right:0;max-height:240px;overflow-y:auto;background:#fff;border:1px solid var(--color-border);border-radius:8px;box-shadow:var(--shadow);padding:4px}.combobox-option{display:flex;justify-content:space-between;gap:8px;width:100%;text-align:left;padding:8px 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label{font-size:11px;text-transform:uppercase;letter-spacing:.03em;color:var(--color-muted)}.filter-field input,.filter-field select{padding:8px 10px;border:1px solid var(--color-border);border-radius:6px;font-size:14px;font-family:inherit;background:#fff}.filter-field input:disabled,.filter-field select:disabled{background:#f8fafc;color:var(--color-muted)}.filter-field .search-input-wrap input{padding:10px 12px 10px 36px}.pagination{display:flex;align-items:center;justify-content:center;gap:16px;margin-top:16px;font-size:14px;color:var(--color-muted)}.pagination button{background:none;border:1px solid var(--color-border);border-radius:6px;padding:6px;display:inline-flex;cursor:pointer;color:var(--color-text)}.pagination button:disabled{opacity:.4;cursor:not-allowed}.profile-list{display:grid;grid-template-columns:160px 1fr;grid-gap:10px 12px;gap:10px 12px;margin:0}.profile-list dt{color:var(--color-muted);font-size:13px;font-weight:600}.profile-list dd{margin:0;font-size:14px}