/**
 * 管理后台样式
 * 侧边栏布局，数据表格，表单，弹窗
 */

:root {
  --primary: #38bdf8;
  --primary-dark: #0ea5e9;
  --danger: #ef4444;
  --success: #22c55e;
  --bg: #f8fafc;
  --card: #ffffff;
  --text: #1e293b;
  --text-secondary: #64748b;
  --border: #e2e8f0;
  --sidebar-width: 220px;
  --radius: 12px;
}

[data-theme="dark"] {
  --bg: #0f172a;
  --card: #1e293b;
  --text: #f1f5f9;
  --text-secondary: #94a3b8;
  --border: #334155;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
}

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

.sidebar {
  width: var(--sidebar-width);
  background: var(--card);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: fixed;
  height: 100vh;
  z-index: 50;
}

.sidebar-brand {
  padding: 20px;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--primary-dark);
  border-bottom: 1px solid var(--border);
}

.sidebar-nav {
  flex: 1;
  padding: 12px 0;
}

.nav-item {
  display: block;
  padding: 12px 20px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.95rem;
  transition: all 0.2s;
  border-left: 3px solid transparent;
}

.nav-item:hover { background: var(--bg); color: var(--primary); }
.nav-item.active { background: var(--bg); color: var(--primary); border-left-color: var(--primary); }

.sidebar-footer {
  padding: 16px;
  border-top: 1px solid var(--border);
}

.sidebar-footer button {
  width: 100%;
  padding: 10px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s;
}

.sidebar-footer button:hover { color: var(--danger); border-color: var(--danger); }

.admin-main {
  margin-left: var(--sidebar-width);
  flex: 1;
  padding: 24px;
  min-height: 100vh;
}

/* ===== 登录页 ===== */
.login-page {
  position: fixed;
  inset: 0;
  background: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
}

.login-box {
  background: var(--card);
  padding: 40px;
  border-radius: var(--radius);
  box-shadow: 0 10px 25px rgba(0,0,0,0.1);
  width: 100%;
  max-width: 360px;
  text-align: center;
}

.login-box h2 { margin-bottom: 24px; color: var(--primary-dark); }

.login-box input {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  color: var(--text);
  font-size: 1rem;
  margin-bottom: 16px;
  outline: none;
}

.login-box input:focus { border-color: var(--primary); }

.login-box button {
  width: 100%;
  padding: 12px;
  border: none;
  border-radius: var(--radius);
  background: var(--primary);
  color: #fff;
  font-size: 1rem;
  cursor: pointer;
  transition: background 0.2s;
}

.login-box button:hover { background: var(--primary-dark); }

.login-tip {
  margin-top: 12px;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

/* ===== 标签页 ===== */
.tab-content { display: none; }
.tab-content.active { display: block; }

/* ===== 仪表盘 ===== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 16px;
  margin-top: 20px;
}

.stat-card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 20px;
  text-align: center;
  border: 1px solid var(--border);
}

.stat-value {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary-dark);
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* ===== 区域头部 ===== */
.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.section-actions { display: flex; gap: 8px; }

/* ===== 按钮 ===== */
.btn-primary, .btn-danger {
  padding: 8px 16px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: opacity 0.2s;
}

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { opacity: 0.9; }

.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { opacity: 0.9; }

/* ===== 筛选栏 ===== */
.filter-bar {
  display: flex;
  gap: 12px;
  margin-bottom: 16px;
}

.filter-bar input, .filter-bar select {
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  font-size: 0.9rem;
}

/* ===== 数据表格 ===== */
.data-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--card);
  border-radius: var(--radius);
  overflow: hidden;
}

.data-table th, .data-table td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
}

.data-table th {
  background: var(--bg);
  font-weight: 600;
  color: var(--text-secondary);
}

.data-table td { color: var(--text); }

.data-table tr:hover { background: var(--bg); }

.status-badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 12px;
  font-size: 0.75rem;
}

.status-online { background: #dcfce7; color: #166534; }
.status-offline { background: #fee2e2; color: #991b1b; }

.btn-sm {
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: transparent;
  color: var(--text);
  cursor: pointer;
  font-size: 0.8rem;
  margin-right: 4px;
}

.btn-sm:hover { background: var(--bg); }

/* ===== 分页 ===== */
.pagination {
  display: flex;
  justify-content: center;
  gap: 6px;
  margin-top: 16px;
}

.pagination button {
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--card);
  color: var(--text);
  cursor: pointer;
}

.pagination button.active { background: var(--primary); color: #fff; border-color: var(--primary); }
.pagination button:disabled { opacity: 0.5; cursor: not-allowed; }

/* ===== 背景图网格 ===== */
.bg-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 16px;
}

.bg-card {
  background: var(--card);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
}

.bg-card img {
  width: 100%;
  aspect-ratio: 4/3;
  object-fit: cover;
  display: block;
}

.bg-card-info {
  padding: 10px 12px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.bg-card-info span { font-size: 0.8rem; color: var(--text-secondary); }

/* ===== 表单 ===== */
.form-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
  margin: 20px 0;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-group.full { grid-column: 1 / -1; }

.form-group label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.form-group input, .form-group select {
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  font-size: 0.95rem;
}

.form-group input[type="color"] { padding: 4px; height: 40px; }

/* ===== 弹窗 ===== */
.modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 200;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal.active { display: flex; }

.modal-box {
  background: var(--card);
  border-radius: var(--radius);
  max-width: 500px;
  width: 100%;
  padding: 24px;
  animation: modalIn 0.2s ease;
}

.modal-box h3 { margin-bottom: 16px; }

.modal-box textarea, .modal-box input[type="text"], .modal-box input[type="file"] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  color: var(--text);
  margin-bottom: 12px;
  font-size: 0.95rem;
}

.modal-box textarea { resize: vertical; }

.modal-actions {
  display: flex;
  gap: 10px;
  justify-content: flex-end;
  margin-top: 8px;
}

.modal-actions button {
  padding: 8px 16px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
}

.modal-actions button:last-child {
  background: var(--bg);
  color: var(--text);
}

.hint {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin: 8px 0;
}

@keyframes modalIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .sidebar { width: 100%; position: relative; height: auto; }
  .admin-layout { flex-direction: column; }
  .admin-main { margin-left: 0; padding: 16px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .section-header { flex-direction: column; gap: 10px; align-items: flex-start; }
  .data-table { font-size: 0.8rem; }
  .data-table th, .data-table td { padding: 8px; }
}