/* ===== 后台管理样式（纯白 · 直白清晰） ===== */
:root {
  --bg: #f5f7fa;
  --bg-2: #ffffff;
  --bg-3: #eef3ff;
  --primary: #0052d9;
  --primary-2: #2b7fff;
  --text: #1f2329;
  --muted: #646a73;
  --light: #8a919f;
  --card: #ffffff;
  --border: #e5e6eb;
  --success: #00a870;
  --danger: #e34d59;
  --warning: #ed7b2f;
}

body { background: var(--bg); }

.admin-wrap { display: flex; min-height: 100vh; }

/* 侧边栏 */
.admin-side {
  width: 220px; flex-shrink: 0;
  background: #fff;
  border-right: 1px solid var(--border);
  padding: 16px 12px;
  position: sticky; top: 0; height: 100vh; overflow-y: auto;
}
.admin-side .brand { margin: 6px 12px 20px; font-size: 18px; color: var(--primary); }
.admin-side .brand .dot { background: var(--primary); }
.admin-side a {
  display: flex; align-items: center; gap: 11px;
  padding: 10px 14px; border-radius: 6px;
  color: #4e5969; margin-bottom: 2px; font-size: 14px;
}
.admin-side a:hover { background: #f2f3f5; color: var(--text); }
.admin-side a.active { background: var(--bg-3); color: var(--primary); font-weight: 600; }
.admin-side a i { width: 16px; text-align: center; }

/* 主区域 */
.admin-main { flex: 1; min-width: 0; padding: 24px 28px; background: var(--bg); }
.admin-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px; }
.admin-head h2 { margin: 0; color: var(--text); font-size: 20px; font-weight: 600; }

/* 卡片 */
.card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 22px;
  margin-bottom: 18px;
}

/* 统计 */
.stat-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 16px; }
.stat { background: #fff; border: 1px solid var(--border); border-radius: 8px; padding: 20px; }
.stat .num { font-size: 26px; font-weight: 700; color: var(--text); }
.stat .label { color: var(--muted); font-size: 13px; margin-top: 4px; }

.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* 后台表格（覆盖前台细节） */
.admin-main table th { background: #f7f8fa; color: var(--muted); font-weight: 600; }
.admin-main table td { color: var(--text); }

/* 后台通知 */
.admin-main .alert { border-radius: 6px; }

@media (max-width: 900px) {
  .admin-wrap { flex-direction: column; }
  .admin-side { width: 100%; height: auto; position: static; display: flex; flex-wrap: wrap; padding: 8px; border-right: 0; border-bottom: 1px solid var(--border); }
  .admin-side .brand { width: 100%; margin: 4px 8px 8px; }
  .admin-side a { padding: 7px 10px; font-size: 13px; margin: 0 2px 2px 0; }
  .admin-main { padding: 14px; }
  .stat-grid, .grid-2 { grid-template-columns: 1fr; }
  .table-wrap { overflow-x: auto; }
  .admin-main table { min-width: 680px; }
  .admin-head { flex-wrap: wrap; gap: 8px; }
}