/* ===== 重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
:root {
  --bg: #f0f2f5;
  --card: #ffffff;
  --text: #1e293b;
  --text-2: #64748b;
  --text-3: #94a3b8;
  --border: #e2e8f0;
  --primary: #6366f1;
  --primary-light: #eef2ff;
  --primary-dark: #4f46e5;
  --success: #22c55e;
  --warning: #f59e0b;
  --danger: #ef4444;
  --radius: 12px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,.05);
  --shadow: 0 2px 8px rgba(0,0,0,.06);
  --shadow-lg: 0 8px 24px rgba(0,0,0,.08);
}
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 14px;
  line-height: 1.6;
}
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; }
input, select, textarea { font-family: inherit; font-size: 14px; }

/* ===== 后台布局 ===== */
.admin-layout { display: flex; min-height: 100vh; }

/* 侧边栏 */
.sidebar {
  width: 240px;
  background: #1e293b;
  color: #cbd5e1;
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0; left: 0; bottom: 0;
  z-index: 100;
  transition: transform .3s;
}
.sidebar-logo {
  padding: 20px 24px;
  font-size: 18px;
  font-weight: 700;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 10px;
  border-bottom: 1px solid rgba(255,255,255,.08);
}
.sidebar-logo .logo-icon {
  width: 32px; height: 32px;
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px;
}
.sidebar-nav { padding: 12px; flex: 1; overflow-y: auto; }
.sidebar-nav a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 8px;
  color: #94a3b8;
  margin-bottom: 2px;
  transition: all .15s;
  font-weight: 500;
}
.sidebar-nav a:hover { background: rgba(255,255,255,.06); color: #e2e8f0; }
.sidebar-nav a.active { background: var(--primary); color: #fff; }
.sidebar-nav a .nav-icon { width: 20px; height: 20px; flex-shrink: 0; }
.sidebar-footer {
  padding: 16px 24px;
  border-top: 1px solid rgba(255,255,255,.08);
  font-size: 12px;
  color: #64748b;
}
.sidebar-footer a { color: #94a3b8; }
.sidebar-footer a:hover { color: #fff; }

/* 主内容区 */
.admin-main {
  flex: 1;
  margin-left: 240px;
  padding: 0;
}
.admin-topbar {
  height: 60px;
  background: var(--card);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  position: sticky; top: 0; z-index: 50;
}
.admin-topbar h1 { font-size: 18px; font-weight: 600; }
.topbar-actions { display: flex; align-items: center; gap: 12px; }

.admin-content { padding: 24px; }

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: all .15s;
  white-space: nowrap;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-outline { background: transparent; color: var(--text); border: 1px solid var(--border); }
.btn-outline:hover { background: var(--bg); border-color: var(--text-3); }
.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { background: #dc2626; }
.btn-success { background: var(--success); color: #fff; }
.btn-sm { padding: 4px 10px; font-size: 12px; border-radius: 6px; }
.btn-icon {
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; border-radius: 6px;
  border: 1px solid var(--border); background: var(--card);
  color: var(--text-2); transition: all .15s;
}
.btn-icon:hover { background: var(--bg); color: var(--text); }
.btn-icon.danger:hover { color: var(--danger); border-color: var(--danger); }

/* ===== 卡片 ===== */
.card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  overflow: hidden;
}

/* 统计卡片 */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}
.stat-card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 16px;
}
.stat-icon {
  width: 48px; height: 48px;
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px;
  flex-shrink: 0;
}
.stat-icon.blue { background: #dbeafe; color: #2563eb; }
.stat-icon.green { background: #dcfce7; color: #16a34a; }
.stat-icon.purple { background: #ede9fe; color: #7c3aed; }
.stat-icon.orange { background: #fef3c7; color: #d97706; }
.stat-value { font-size: 28px; font-weight: 700; line-height: 1.2; }
.stat-label { font-size: 13px; color: var(--text-2); }

/* 表格 */
.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
thead th {
  text-align: left;
  padding: 12px 16px;
  font-weight: 600;
  font-size: 13px;
  color: var(--text-2);
  border-bottom: 2px solid var(--border);
  background: #f8fafc;
  white-space: nowrap;
}
tbody td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}
tbody tr:hover { background: #f8fafc; }
tbody tr:last-child td { border-bottom: none; }

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 2px 10px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 500;
}
.tag::before {
  content: '';
  width: 6px; height: 6px;
  border-radius: 50%;
  margin-right: 6px;
  background: currentColor;
}

/* 分页 */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 16px;
}
.pagination a, .pagination span {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 32px; height: 32px;
  border-radius: 6px;
  padding: 0 8px;
  font-size: 13px;
}
.pagination a { border: 1px solid var(--border); color: var(--text); }
.pagination a:hover { background: var(--primary-light); border-color: var(--primary); color: var(--primary); }
.pagination .current { background: var(--primary); color: #fff; border: 1px solid var(--primary); }

/* 模态框 */
.modal-overlay {
  position: fixed; inset: 0;
  background: rgba(0,0,0,.4);
  display: none;
  align-items: center; justify-content: center;
  z-index: 1000;
}
.modal-overlay.visible { display: flex; }
.modal-box {
  background: var(--card);
  border-radius: 16px;
  width: 90%; max-width: 480px;
  max-height: 90vh; overflow-y: auto;
  box-shadow: var(--shadow-lg);
  animation: modalIn .2s ease;
}
@keyframes modalIn { from { opacity:0; transform: scale(.96) translateY(10px); } to { opacity:1; transform: scale(1); } }
.modal-header {
  padding: 20px 24px 12px;
  font-size: 18px; font-weight: 600;
  display: flex; justify-content: space-between; align-items: center;
}
.modal-close {
  width: 32px; height: 32px;
  display: flex; align-items: center; justify-content: center;
  border: none; background: transparent;
  font-size: 20px; color: var(--text-3);
  border-radius: 6px; cursor: pointer;
}
.modal-close:hover { background: var(--bg); color: var(--text); }
.modal-body { padding: 0 24px 24px; }

/* 表单 */
.form-group { margin-bottom: 16px; }
.form-group label {
  display: block;
  font-size: 13px; font-weight: 500;
  color: var(--text-2);
  margin-bottom: 6px;
}
.form-group input, .form-group select, .form-group textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  outline: none;
  transition: border-color .15s;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}
.form-group textarea { resize: vertical; min-height: 80px; }

/* Toast */
.toast {
  position: fixed; top: 20px; right: 20px;
  padding: 12px 20px;
  border-radius: 10px;
  font-size: 14px; font-weight: 500;
  z-index: 9999;
  transform: translateX(120%);
  transition: transform .3s;
  box-shadow: var(--shadow-lg);
}
.toast.show { transform: translateX(0); }
.toast.success { background: #22c55e; color: #fff; }
.toast.error { background: #ef4444; color: #fff; }

/* 空状态 */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-3);
}
.empty-state .empty-icon { font-size: 48px; margin-bottom: 12px; }
.empty-state p { margin-bottom: 16px; }

/* 工具栏 */
.toolbar {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}
.toolbar .spacer { flex: 1; }
.search-input {
  position: relative;
  display: inline-flex;
  align-items: center;
}
.search-input input {
  padding: 8px 12px 8px 36px;
  border: 1px solid var(--border);
  border-radius: 8px;
  width: 260px;
  outline: none;
}
.search-input input:focus { border-color: var(--primary); }
.search-input svg {
  position: absolute; left: 10px;
  color: var(--text-3);
  pointer-events: none;
}

/* 移动端 */
.sidebar-toggle { display: none; }
@media (max-width: 768px) {
  .sidebar { transform: translateX(-100%); }
  .sidebar.open { transform: translateX(0); }
  .admin-main { margin-left: 0; }
  .sidebar-toggle { display: flex; }
  .search-input input { width: 160px; }
}