:root {
  --primary: #1a56db;
  --primary-dark: #1e3a8a;
  --accent: #06b6d4;
  --dark: #0f172a;
  --dark-2: #1e293b;
  --sidebar-bg: #0f172a;
  --sidebar-hover: #1e293b;
  --sidebar-active: #1a56db;
  --gray: #64748b;
  --gray-light: #e2e8f0;
  --bg: #f1f5f9;
  --white: #fff;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --info: #3b82f6;
  --radius: 10px;
  --shadow: 0 1px 3px rgba(0,0,0,0.1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif; background: var(--bg); color: var(--dark); }

/* ===== Login ===== */
.login-page { min-height: 100vh; display: flex; align-items: center; justify-content: center; background: linear-gradient(135deg, #0f172a 0%, #1e3a8a 100%); }
.login-card { background: #fff; border-radius: 20px; padding: 48px; width: 400px; max-width: 90%; box-shadow: 0 20px 60px rgba(0,0,0,0.3); }
.login-logo { text-align: center; margin-bottom: 32px; }
.login-logo .icon { width: 64px; height: 64px; background: linear-gradient(135deg, #1a56db, #06b6d4); border-radius: 16px; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 32px; margin: 0 auto 16px; }
.login-logo h1 { font-size: 24px; color: var(--dark); }
.login-logo p { font-size: 14px; color: var(--gray); margin-top: 4px; }
.login-form .form-group { margin-bottom: 20px; }
.login-form label { display: block; font-size: 14px; font-weight: 500; margin-bottom: 8px; color: var(--dark-2); }
.login-form input { width: 100%; padding: 12px 16px; border: 1px solid var(--gray-light); border-radius: 8px; font-size: 15px; transition: border-color 0.2s; }
.login-form input:focus { outline: none; border-color: var(--primary); }
.login-btn { width: 100%; padding: 14px; background: linear-gradient(135deg, #1a56db, #06b6d4); border: none; border-radius: 8px; color: #fff; font-size: 16px; font-weight: 600; cursor: pointer; transition: all 0.2s; }
.login-btn:hover { transform: translateY(-1px); box-shadow: 0 4px 14px rgba(26,86,219,0.3); }
.login-error { color: var(--danger); font-size: 14px; margin-bottom: 16px; display: none; }

/* ===== Layout ===== */
.admin-layout { display: flex; min-height: 100vh; }
.sidebar { width: 240px; background: var(--sidebar-bg); color: #fff; position: fixed; top: 0; left: 0; bottom: 0; overflow-y: auto; z-index: 100; }
.sidebar-header { padding: 20px 24px; border-bottom: 1px solid rgba(255,255,255,0.1); }
.sidebar-header .logo { display: flex; align-items: center; gap: 10px; }
.sidebar-header .icon { width: 36px; height: 36px; background: linear-gradient(135deg, #1a56db, #06b6d4); border-radius: 8px; display: flex; align-items: center; justify-content: center; font-size: 18px; }
.sidebar-header span { font-size: 18px; font-weight: 700; }
.sidebar-nav { padding: 16px 0; }
.sidebar-nav a { display: flex; align-items: center; gap: 12px; padding: 12px 24px; color: rgba(255,255,255,0.6); font-size: 14px; transition: all 0.2s; border-left: 3px solid transparent; }
.sidebar-nav a:hover { background: var(--sidebar-hover); color: #fff; }
.sidebar-nav a.active { background: var(--sidebar-hover); color: #fff; border-left-color: var(--accent); }
.sidebar-nav a .icon { font-size: 18px; }
.sidebar-footer { padding: 20px 24px; border-top: 1px solid rgba(255,255,255,0.1); margin-top: auto; }
.sidebar-footer .user-info { display: flex; align-items: center; gap: 10px; }
.sidebar-footer .avatar { width: 36px; height: 36px; background: var(--primary); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 14px; font-weight: 600; }
.sidebar-footer .info { flex: 1; }
.sidebar-footer .info .name { font-size: 14px; color: #fff; }
.sidebar-footer .info .role { font-size: 12px; color: rgba(255,255,255,0.4); }
.sidebar-footer .logout { color: rgba(255,255,255,0.4); cursor: pointer; font-size: 14px; transition: color 0.2s; }
.sidebar-footer .logout:hover { color: var(--danger); }

.main-content { flex: 1; margin-left: 240px; }
.topbar { height: 60px; background: #fff; border-bottom: 1px solid var(--gray-light); display: flex; align-items: center; justify-content: space-between; padding: 0 24px; position: sticky; top: 0; z-index: 50; }
.topbar h1 { font-size: 20px; font-weight: 600; }
.topbar .actions { display: flex; gap: 12px; align-items: center; }
.content-body { padding: 24px; }

/* ===== Cards ===== */
.card { background: #fff; border-radius: var(--radius); box-shadow: var(--shadow); overflow: hidden; margin-bottom: 24px; }
.card-header { padding: 16px 24px; border-bottom: 1px solid var(--gray-light); display: flex; align-items: center; justify-content: space-between; }
.card-header h2 { font-size: 16px; font-weight: 600; }
.card-body { padding: 24px; }

/* Stats */
.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px; margin-bottom: 24px; }
.stat-card { background: #fff; border-radius: var(--radius); padding: 24px; box-shadow: var(--shadow); transition: transform 0.2s; }
.stat-card:hover { transform: translateY(-2px); }
.stat-card .stat-icon { width: 48px; height: 48px; border-radius: 12px; display: flex; align-items: center; justify-content: center; font-size: 22px; margin-bottom: 12px; }
.stat-card .stat-value { font-size: 28px; font-weight: 700; color: var(--dark); }
.stat-card .stat-label { font-size: 13px; color: var(--gray); }
.stat-card.blue .stat-icon { background: rgba(26,86,219,0.1); }
.stat-card.green .stat-icon { background: rgba(16,185,129,0.1); }
.stat-card.orange .stat-icon { background: rgba(245,158,11,0.1); }
.stat-card.red .stat-icon { background: rgba(239,68,68,0.1); }

/* Table */
.data-table { width: 100%; border-collapse: collapse; }
.data-table th { text-align: left; padding: 12px 16px; background: var(--bg); font-size: 13px; font-weight: 600; color: var(--gray); border-bottom: 1px solid var(--gray-light); white-space: nowrap; }
.data-table td { padding: 12px 16px; border-bottom: 1px solid var(--gray-light); font-size: 14px; }
.data-table tr:hover { background: var(--bg); }

/* Badge */
.badge { display: inline-block; padding: 2px 10px; border-radius: 4px; font-size: 12px; font-weight: 500; }
.badge-blue { background: rgba(59,130,246,0.1); color: var(--info); }
.badge-green { background: rgba(16,185,129,0.1); color: var(--success); }
.badge-orange { background: rgba(245,158,11,0.1); color: var(--warning); }
.badge-red { background: rgba(239,68,68,0.1); color: var(--danger); }
.badge-gray { background: var(--gray-light); color: var(--gray); }

/* Score badge */
.score-badge { display: inline-flex; align-items: center; justify-content: center; min-width: 40px; padding: 4px 8px; border-radius: 6px; font-size: 14px; font-weight: 700; }
.score-excellent { background: rgba(16,185,129,0.15); color: var(--success); }
.score-good { background: rgba(59,130,246,0.15); color: var(--info); }
.score-average { background: rgba(245,158,11,0.15); color: var(--warning); }
.score-poor { background: rgba(239,68,68,0.15); color: var(--danger); }

/* Buttons */
.btn { padding: 8px 16px; border: none; border-radius: 6px; font-size: 14px; font-weight: 500; cursor: pointer; transition: all 0.2s; display: inline-flex; align-items: center; gap: 6px; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-success { background: var(--success); color: #fff; }
.btn-success:hover { opacity: 0.9; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { opacity: 0.9; }
.btn-warning { background: var(--warning); color: #fff; }
.btn-gray { background: var(--gray-light); color: var(--dark-2); }
.btn-sm { padding: 6px 10px; font-size: 13px; }

/* Form */
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-bottom: 20px; }
.form-row.single { grid-template-columns: 1fr; }
.form-field { margin-bottom: 20px; }
.form-field label { display: block; font-size: 14px; font-weight: 500; margin-bottom: 8px; color: var(--dark-2); }
.form-field input, .form-field textarea, .form-field select {
  width: 100%; padding: 10px 14px; border: 1px solid var(--gray-light); border-radius: 8px; font-size: 14px; font-family: inherit; transition: border-color 0.2s;
}
.form-field input:focus, .form-field textarea:focus, .form-field select:focus { outline: none; border-color: var(--primary); }
.form-field textarea { resize: vertical; min-height: 100px; }

/* Filter bar */
.filter-bar { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; margin-bottom: 20px; }
.filter-bar input, .filter-bar select { padding: 8px 14px; border: 1px solid var(--gray-light); border-radius: 8px; font-size: 14px; }
.filter-bar input { flex: 1; min-width: 200px; }

/* Pagination */
.admin-pagination { display: flex; justify-content: center; gap: 8px; margin-top: 20px; }
.admin-pagination button { padding: 6px 12px; border: 1px solid var(--gray-light); background: #fff; border-radius: 6px; cursor: pointer; font-size: 13px; }
.admin-pagination button.active { background: var(--primary); color: #fff; border-color: var(--primary); }
.admin-pagination button:disabled { opacity: 0.4; cursor: not-allowed; }

/* Modal */
.admin-modal-overlay { position: fixed; top: 0; left: 0; right: 0; bottom: 0; background: rgba(0,0,0,0.5); backdrop-filter: blur(4px); display: none; align-items: center; justify-content: center; z-index: 1000; padding: 20px; }
.admin-modal-overlay.show { display: flex; }
.admin-modal { background: #fff; border-radius: 12px; max-width: 600px; width: 100%; max-height: 90vh; overflow-y: auto; }
.admin-modal-header { padding: 20px 24px; border-bottom: 1px solid var(--gray-light); display: flex; align-items: center; justify-content: space-between; }
.admin-modal-header h2 { font-size: 18px; }
.admin-modal-close { background: none; border: none; font-size: 24px; cursor: pointer; color: var(--gray); }
.admin-modal-body { padding: 24px; }
.admin-modal-footer { padding: 16px 24px; border-top: 1px solid var(--gray-light); display: flex; justify-content: flex-end; gap: 12px; }

/* Toast (reuse from frontend) */
.toast { position: fixed; bottom: 30px; left: 50%; transform: translateX(-50%) translateY(100px); background: var(--dark); color: #fff; padding: 12px 24px; border-radius: 8px; font-size: 14px; z-index: 3000; transition: transform 0.3s; }
.toast.show { transform: translateX(-50%) translateY(0); }
.toast.success { background: var(--success); }
.toast.error { background: var(--danger); }

/* Empty state */
.empty-state { text-align: center; padding: 60px 20px; color: var(--gray); }
.empty-state .icon { font-size: 48px; margin-bottom: 16px; }

/* Chart bars */
.chart-container { display: flex; align-items: flex-end; gap: 12px; height: 200px; padding: 20px 0; }
.chart-bar { flex: 1; display: flex; flex-direction: column; align-items: center; gap: 8px; }
.chart-bar .bar { width: 100%; border-radius: 6px 6px 0 0; transition: height 0.5s; min-height: 4px; }
.chart-bar .label { font-size: 12px; color: var(--gray); }
.chart-bar .value { font-size: 14px; font-weight: 600; }

/* Settings */
.settings-section { margin-bottom: 32px; }
.settings-section h3 { font-size: 16px; margin-bottom: 16px; padding-bottom: 8px; border-bottom: 1px solid var(--gray-light); }
.settings-grid { display: grid; grid-template-columns: 200px 1fr; gap: 16px; align-items: center; margin-bottom: 16px; }
.settings-grid label { font-size: 14px; font-weight: 500; color: var(--dark-2); }
.settings-grid input, .settings-grid select { padding: 10px 14px; border: 1px solid var(--gray-light); border-radius: 8px; font-size: 14px; }
.settings-hint { font-size: 12px; color: var(--gray); margin-top: 4px; }

@media (max-width: 768px) {
  .sidebar { transform: translateX(-100%); transition: transform 0.3s; }
  .sidebar.open { transform: translateX(0); }
  .main-content { margin-left: 0; }
  .form-row { grid-template-columns: 1fr; }
  .settings-grid { grid-template-columns: 1fr; }
  .data-table { font-size: 12px; }
  .data-table th, .data-table td { padding: 8px; }
}

/* Rich text editor */
.rich-editor-toolbar {
  display: flex; flex-wrap: wrap; align-items: center; gap: 4px;
  padding: 8px 10px; background: #f8fafc; border: 1px solid var(--gray-light);
  border-radius: 8px 8px 0 0; border-bottom: none;
}
.rich-editor-toolbar button {
  min-width: 32px; height: 32px; padding: 0 8px; border: none; background: #fff;
  border-radius: 6px; cursor: pointer; font-size: 14px; color: var(--dark-2);
  transition: background 0.2s;
}
.rich-editor-toolbar button:hover { background: #e0f2fe; }
.toolbar-divider { width: 1px; height: 20px; background: var(--gray-light); margin: 0 4px; }
.rich-editor {
  min-height: 300px; padding: 16px; border: 1px solid var(--gray-light);
  border-radius: 0 0 8px 8px; outline: none; font-size: 14px; line-height: 1.8;
  background: #fff; overflow-y: auto;
}
.rich-editor:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(26,86,219,0.1); }
.rich-editor table { width: 100%; border-collapse: collapse; margin: 12px 0; }
.rich-editor table td, .rich-editor table th {
  border: 1px solid #e2e8f0; padding: 8px 12px; min-width: 60px;
}
.rich-editor table th { background: #f1f5f9; font-weight: 600; }
.rich-editor h2 { font-size: 20px; margin: 16px 0 8px; }
.rich-editor h3 { font-size: 17px; margin: 14px 0 6px; }
.rich-editor ul, .rich-editor ol { padding-left: 24px; margin: 8px 0; }
.rich-editor p { margin-bottom: 12px; }
.rich-editor a { color: var(--primary); text-decoration: underline; }
.rich-editor img { max-width: 100%; border-radius: 6px; }