/* ============================================================
   游戏软件分享站 - 主样式表
   设计风格：简约清爽、低带宽适配、响应式
   ============================================================ */

/* CSS 变量 */
:root {
  --primary: #4F46E5;
  --primary-light: #818CF8;
  --primary-dark: #3730A3;
  --success: #10B981;
  --warning: #F59E0B;
  --danger: #EF4444;
  --info: #06B6D4;
  --gray-50: #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-300: #D1D5DB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-700: #374151;
  --gray-800: #1F2937;
  --gray-900: #111827;
  --radius-sm: 4px;
  --radius: 8px;
  --radius-lg: 12px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow: 0 2px 8px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.15);
  --transition: 0.2s ease;
  --max-width: 1200px;
  --header-height: 64px;
}

/* 重置样式 */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--gray-50);
  color: var(--gray-900);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--primary-dark);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

button {
  cursor: pointer;
  font-family: inherit;
  font-size: inherit;
}

input, select, textarea {
  font-family: inherit;
  font-size: inherit;
}

/* ============================================================
   布局容器
   ============================================================ */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

.section {
  padding: 40px 0;
}

.section-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.section-title::before {
  content: '';
  display: inline-block;
  width: 4px;
  height: 24px;
  background: var(--primary);
  border-radius: 2px;
}

/* ============================================================
   顶部导航栏
   ============================================================ */
.header {
  background: white;
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
}

.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo a {
  font-size: 20px;
  font-weight: 800;
  color: var(--primary);
  text-decoration: none;
  letter-spacing: -0.5px;
}

.logo span {
  color: var(--gray-900);
}

/* 导航菜单 */
.nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav a {
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  color: var(--gray-700);
  text-decoration: none;
  font-weight: 500;
  font-size: 14px;
  transition: all var(--transition);
  white-space: nowrap;
}

.nav a:hover {
  background: var(--gray-100);
  color: var(--primary);
}

.nav a.active {
  background: var(--primary);
  color: white;
}

/* 管理员链接 */
.admin-link {
  background: var(--primary) !important;
  color: white !important;
  padding: 8px 16px !important;
  border-radius: var(--radius-sm) !important;
  font-weight: 600 !important;
}

.admin-link:hover {
  background: var(--primary-dark) !important;
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  color: var(--gray-700);
  padding: 4px;
}

/* 搜索框（导航内） */
.nav-search {
  display: flex;
  align-items: center;
  background: var(--gray-100);
  border-radius: 20px;
  padding: 6px 12px;
  margin-left: 8px;
}

.nav-search input {
  border: none;
  background: transparent;
  outline: none;
  width: 140px;
  font-size: 14px;
  color: var(--gray-700);
}

.nav-search input::placeholder {
  color: var(--gray-400);
}

.nav-search button {
  background: none;
  border: none;
  color: var(--gray-500);
  padding: 2px 4px;
  cursor: pointer;
}

/* ============================================================
   公告栏
   ============================================================ */
.announcements {
  background: var(--gray-100);
  border-bottom: 1px solid var(--gray-200);
  overflow: hidden;
}

.announcement-item {
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  margin: 6px 0;
  font-size: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.announcement-item a {
  color: var(--primary);
  font-weight: 600;
}

.announcement-info {
  background: #EFF6FF;
  border-left: 4px solid var(--info);
}

.announcement-warning {
  background: #FFFBEB;
  border-left: 4px solid var(--warning);
}

.announcement-success {
  background: #ECFDF5;
  border-left: 4px solid var(--success);
}

.announcement-error {
  background: #FEF2F2;
  border-left: 4px solid var(--danger);
}

.announcement-icon {
  font-size: 16px;
  flex-shrink: 0;
}

/* ============================================================
   分类网格（首页）
   ============================================================ */
.categories-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.category-card {
  background: white;
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  text-decoration: none;
  color: var(--gray-900);
  transition: all var(--transition);
  border: 2px solid transparent;
}

.category-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.category-icon {
  font-size: 48px;
  margin-bottom: 12px;
  display: block;
}

.category-name {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 4px;
}

.category-desc {
  font-size: 13px;
  color: var(--gray-500);
}

/* ============================================================
   资源卡片
   ============================================================ */
.resources-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

.resource-card {
  background: white;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
  border: 1px solid var(--gray-200);
}

.resource-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.resource-card a {
  text-decoration: none;
  color: inherit;
  display: block;
}

.resource-cover {
  width: 100%;
  height: 160px;
  object-fit: cover;
  background: var(--gray-100);
}

.resource-cover-placeholder {
  width: 100%;
  height: 160px;
  background: linear-gradient(135deg, var(--gray-100), var(--gray-200));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 48px;
  color: var(--gray-400);
}

.resource-info {
  padding: 16px;
}

.resource-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--gray-900);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.resource-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--gray-500);
  font-size: 13px;
  margin-bottom: 8px;
}

.resource-meta span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.resource-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}

.resource-tag {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 500;
  background: var(--gray-100);
  color: var(--gray-600);
}

/* ============================================================
   轮播图
   ============================================================ */
.carousel {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: 40px;
  background: var(--gray-200);
  aspect-ratio: 3 / 1;
}

.carousel-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 0.5s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  font-size: 32px;
  font-weight: 800;
}

.carousel-slide.active {
  opacity: 1;
}

.carousel-slide a {
  color: white;
  text-decoration: none;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.carousel-dots {
  position: absolute;
  bottom: 16px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 8px;
}

.carousel-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255,255,255,0.5);
  cursor: pointer;
  border: none;
  transition: all var(--transition);
}

.carousel-dot.active {
  background: white;
  transform: scale(1.2);
}

/* ============================================================
   按钮
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 24px;
  border-radius: var(--radius);
  border: none;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--primary);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-dark);
  color: white;
}

.btn-secondary {
  background: var(--gray-200);
  color: var(--gray-700);
}

.btn-secondary:hover {
  background: var(--gray-300);
}

.btn-success {
  background: var(--success);
  color: white;
}

.btn-success:hover {
  background: #059669;
  color: white;
}

.btn-danger {
  background: var(--danger);
  color: white;
}

.btn-danger:hover {
  background: #DC2626;
  color: white;
}

.btn-sm {
  padding: 6px 14px;
  font-size: 13px;
}

.btn-lg {
  padding: 14px 36px;
  font-size: 17px;
}

.btn-block {
  width: 100%;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ============================================================
   搜索框
   ============================================================ */
.search-box {
  display: flex;
  gap: 12px;
  margin-bottom: 32px;
}

.search-box input {
  flex: 1;
  padding: 12px 16px;
  border: 2px solid var(--gray-200);
  border-radius: var(--radius);
  font-size: 15px;
  outline: none;
  transition: border-color var(--transition);
  background: white;
}

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

.search-box button {
  padding: 12px 32px;
}

/* 搜索结果统计 */
.search-stats {
  color: var(--gray-500);
  font-size: 14px;
  margin-bottom: 20px;
}

/* ============================================================
   标签筛选
   ============================================================ */
.tags-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.tag-filter {
  padding: 6px 16px;
  border-radius: 20px;
  border: 2px solid var(--gray-200);
  background: white;
  color: var(--gray-600);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
}

.tag-filter:hover {
  border-color: var(--primary-light);
  color: var(--primary);
}

.tag-filter.active {
  background: var(--primary);
  border-color: var(--primary);
  color: white;
}

/* ============================================================
   分页
   ============================================================ */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  padding: 40px 0;
  flex-wrap: wrap;
}

.pagination a,
.pagination span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 40px;
  padding: 0 12px;
  border-radius: var(--radius-sm);
  background: white;
  color: var(--gray-700);
  text-decoration: none;
  font-weight: 500;
  font-size: 14px;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
  border: 1px solid var(--gray-200);
}

.pagination a:hover {
  background: var(--gray-100);
  border-color: var(--primary-light);
  color: var(--primary);
}

.pagination a.active {
  background: var(--primary);
  border-color: var(--primary);
  color: white;
}

.pagination .disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* ============================================================
   资源详情页
   ============================================================ */
.resource-detail {
  background: white;
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 32px;
}

.resource-detail-header {
  display: flex;
  gap: 32px;
  margin-bottom: 32px;
}

.resource-detail-cover {
  width: 280px;
  height: 280px;
  object-fit: cover;
  border-radius: var(--radius-lg);
  background: var(--gray-100);
  flex-shrink: 0;
}

.resource-detail-cover-placeholder {
  width: 280px;
  height: 280px;
  background: linear-gradient(135deg, var(--gray-100), var(--gray-200));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 80px;
  color: var(--gray-400);
  flex-shrink: 0;
}

.resource-detail-info {
  flex: 1;
}

.resource-detail-title {
  font-size: 28px;
  font-weight: 800;
  color: var(--gray-900);
  margin-bottom: 16px;
  line-height: 1.3;
}

.resource-detail-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  margin-bottom: 20px;
}

.resource-detail-meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--gray-600);
  font-size: 14px;
}

.resource-detail-meta-item strong {
  color: var(--gray-900);
}

.resource-detail-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.resource-detail-tag {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 16px;
  font-size: 13px;
  font-weight: 600;
}

.resource-detail-desc {
  color: var(--gray-600);
  line-height: 1.8;
  font-size: 15px;
}

.resource-detail-desc h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--gray-900);
  margin: 24px 0 12px;
}

.resource-detail-desc p {
  margin-bottom: 12px;
}

.resource-detail-desc ul, .resource-detail-desc ol {
  margin: 12px 0;
  padding-left: 24px;
}

/* 下载按钮区域 */
.resource-detail-actions {
  margin-top: 32px;
  display: flex;
  gap: 16px;
  align-items: center;
}

.download-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 40px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: var(--radius);
  font-size: 17px;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
}

.download-btn:hover {
  background: var(--primary-dark);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* 截图展示 */
.resource-screenshots {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
  margin-top: 24px;
}

.resource-screenshot {
  width: 100%;
  border-radius: var(--radius);
  cursor: pointer;
  transition: transform var(--transition);
}

.resource-screenshot:hover {
  transform: scale(1.03);
}

/* ============================================================
   分类页面
   ============================================================ */
.category-header {
  background: white;
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 32px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.category-header-icon {
  font-size: 56px;
  flex-shrink: 0;
}

.category-header-info h1 {
  font-size: 28px;
  font-weight: 800;
  color: var(--gray-900);
  margin-bottom: 8px;
}

.category-header-info p {
  color: var(--gray-500);
  font-size: 15px;
}

/* 排序选项 */
.sort-options {
  display: flex;
  gap: 8px;
  margin-bottom: 24px;
}

.sort-option {
  padding: 6px 16px;
  border-radius: 20px;
  border: 2px solid var(--gray-200);
  background: white;
  color: var(--gray-600);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
}

.sort-option:hover {
  border-color: var(--primary-light);
}

.sort-option.active {
  background: var(--primary);
  border-color: var(--primary);
  color: white;
}

/* ============================================================
   管理员后台
   ============================================================ */
.admin-body {
  background: var(--gray-100);
  min-height: 100vh;
}

.admin-sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: 240px;
  height: 100vh;
  background: var(--gray-900);
  color: white;
  z-index: 200;
  overflow-y: auto;
}

.admin-sidebar-header {
  padding: 20px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
  font-size: 18px;
  font-weight: 700;
}

.admin-sidebar-nav {
  padding: 12px;
}

.admin-sidebar-nav a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  color: rgba(255,255,255,0.7);
  text-decoration: none;
  font-weight: 500;
  font-size: 14px;
  transition: all var(--transition);
  margin-bottom: 4px;
}

.admin-sidebar-nav a:hover {
  background: rgba(255,255,255,0.1);
  color: white;
}

.admin-sidebar-nav a.active {
  background: var(--primary);
  color: white;
}

.admin-main {
  margin-left: 240px;
  padding: 32px;
  min-height: 100vh;
}

.admin-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 32px;
}

.admin-header h1 {
  font-size: 24px;
  font-weight: 800;
}

.admin-user {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--gray-600);
  font-size: 14px;
}

/* 管理表格 */
.admin-table {
  width: 100%;
  background: white;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border-collapse: collapse;
  overflow: hidden;
}

.admin-table th {
  padding: 14px 16px;
  text-align: left;
  font-weight: 600;
  font-size: 13px;
  color: var(--gray-500);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  border-bottom: 2px solid var(--gray-200);
  background: var(--gray-50);
}

.admin-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--gray-100);
  font-size: 14px;
  color: var(--gray-700);
}

.admin-table tr:hover td {
  background: var(--gray-50);
}

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

/* 表单 */
.admin-form {
  background: white;
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  max-width: 800px;
}

.admin-form h2 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 24px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-weight: 600;
  font-size: 14px;
  color: var(--gray-700);
  margin-bottom: 8px;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 10px 14px;
  border: 2px solid var(--gray-200);
  border-radius: var(--radius);
  font-size: 15px;
  outline: none;
  transition: border-color var(--transition);
  background: white;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--primary);
}

.form-group textarea {
  min-height: 120px;
  resize: vertical;
}

.form-group .hint {
  font-size: 12px;
  color: var(--gray-400);
  margin-top: 4px;
}

.form-actions {
  display: flex;
  gap: 12px;
  margin-top: 32px;
}

/* 上传区域 */
.upload-zone {
  border: 2px dashed var(--gray-300);
  border-radius: var(--radius-lg);
  padding: 40px;
  text-align: center;
  cursor: pointer;
  transition: all var(--transition);
  background: var(--gray-50);
}

.upload-zone:hover {
  border-color: var(--primary);
  background: #EEF2FF;
}

.upload-zone.dragover {
  border-color: var(--primary);
  background: #EEF2FF;
}

.upload-zone-icon {
  font-size: 40px;
  margin-bottom: 12px;
  color: var(--gray-400);
}

.upload-zone p {
  color: var(--gray-500);
  font-size: 14px;
}

.upload-zone .filename {
  color: var(--primary);
  font-weight: 600;
  margin-top: 8px;
}

/* ============================================================
   登录页
   ============================================================ */
.login-body {
  background: var(--gray-100);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.login-box {
  background: white;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: 48px;
  width: 100%;
  max-width: 420px;
}

.login-box h1 {
  font-size: 24px;
  font-weight: 800;
  text-align: center;
  margin-bottom: 8px;
  color: var(--gray-900);
}

.login-box .subtitle {
  text-align: center;
  color: var(--gray-500);
  font-size: 14px;
  margin-bottom: 32px;
}

.login-box .form-group {
  margin-bottom: 20px;
}

.login-box .btn {
  width: 100%;
  margin-top: 8px;
}

.login-error {
  background: #FEF2F2;
  color: var(--danger);
  padding: 12px 16px;
  border-radius: var(--radius);
  font-size: 14px;
  margin-bottom: 20px;
  border-left: 4px solid var(--danger);
}

/* ============================================================
   弹窗
   ============================================================ */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.5);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: white;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  width: 90%;
  max-width: 500px;
  max-height: 80vh;
  overflow-y: auto;
  transform: translateY(20px);
  transition: transform var(--transition);
}

.modal-overlay.active .modal {
  transform: translateY(0);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  border-bottom: 1px solid var(--gray-200);
}

.modal-header h3 {
  font-size: 18px;
  font-weight: 700;
}

.modal-close {
  background: none;
  border: none;
  font-size: 24px;
  color: var(--gray-400);
  cursor: pointer;
  padding: 4px;
  line-height: 1;
}

.modal-close:hover {
  color: var(--gray-700);
}

.modal-body {
  padding: 24px;
}

.modal-footer {
  padding: 16px 24px;
  border-top: 1px solid var(--gray-200);
  display: flex;
  justify-content: flex-end;
  gap: 12px;
}

/* ============================================================
   加载状态
   ============================================================ */
.loading-container {
  text-align: center;
  padding: 80px 20px;
  color: var(--gray-500);
}

.loading-spinner {
  width: 40px;
  height: 40px;
  border: 4px solid var(--gray-200);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 0 auto 16px;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* 错误提示 */
.error-container {
  text-align: center;
  padding: 80px 20px;
  color: var(--danger);
}

.error-container h3 {
  font-size: 20px;
  margin-bottom: 12px;
}

/* 空状态 */
.empty-state {
  text-align: center;
  padding: 80px 20px;
  color: var(--gray-400);
}

.empty-state-icon {
  font-size: 64px;
  margin-bottom: 16px;
}

.empty-state p {
  font-size: 16px;
}

/* ============================================================
   Toast 提示
   ============================================================ */
.toast-container {
  position: fixed;
  top: 80px;
  right: 20px;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.toast {
  padding: 14px 20px;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  font-size: 14px;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 10px;
  animation: slideIn 0.3s ease;
  max-width: 360px;
}

.toast-success {
  background: #ECFDF5;
  color: #059669;
  border-left: 4px solid var(--success);
}

.toast-error {
  background: #FEF2F2;
  color: #DC2626;
  border-left: 4px solid var(--danger);
}

.toast-info {
  background: #EFF6FF;
  color: #2563EB;
  border-left: 4px solid var(--info);
}

@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

@keyframes slideOut {
  from { transform: translateX(0); opacity: 1; }
  to { transform: translateX(100%); opacity: 0; }
}

/* ============================================================
   页脚
   ============================================================ */
.footer {
  background: var(--gray-900);
  color: rgba(255,255,255,0.7);
  padding: 40px 0;
  text-align: center;
  font-size: 14px;
  margin-top: 80px;
}

.footer a {
  color: rgba(255,255,255,0.9);
}

/* ============================================================
   响应式设计
   ============================================================ */
@media (max-width: 1024px) {
  .categories-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .resource-detail-header {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .resource-detail-cover,
  .resource-detail-cover-placeholder {
    width: 200px;
    height: 200px;
  }

  .admin-sidebar {
    width: 200px;
  }

  .admin-main {
    margin-left: 200px;
  }
}

@media (max-width: 768px) {
  .header .container {
    flex-wrap: wrap;
  }

  .menu-toggle {
    display: block;
  }

  .nav {
    display: none;
    width: 100%;
    flex-direction: column;
    padding-top: 12px;
    gap: 4px;
  }

  .nav.active {
    display: flex;
  }

  .nav a {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
  }

  .nav-search {
    width: 100%;
    margin-left: 0;
    margin-top: 8px;
  }

  .nav-search input {
    width: 100%;
  }

  .categories-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }

  .category-card {
    padding: 20px 16px;
  }

  .category-icon {
    font-size: 36px;
  }

  .resources-grid {
    grid-template-columns: 1fr;
  }

  .resource-detail-header {
    flex-direction: column;
    align-items: center;
  }

  .resource-detail-cover,
  .resource-detail-cover-placeholder {
    width: 100%;
    max-width: 280px;
    height: auto;
    aspect-ratio: 1;
  }

  .resource-detail-title {
    font-size: 22px;
  }

  .resource-detail-actions {
    flex-direction: column;
  }

  .download-btn {
    width: 100%;
    justify-content: center;
  }

  .carousel {
    aspect-ratio: 2 / 1;
  }

  /* 管理员后台移动端 */
  .admin-sidebar {
    transform: translateX(-100%);
    transition: transform var(--transition);
    width: 240px;
  }

  .admin-sidebar.active {
    transform: translateX(0);
  }

  .admin-main {
    margin-left: 0;
    padding: 20px;
  }

  .admin-table {
    display: block;
    overflow-x: auto;
  }

  .section-title {
    font-size: 20px;
  }
}

@media (max-width: 480px) {
  .categories-grid {
    grid-template-columns: 1fr;
  }

  .login-box {
    padding: 32px 24px;
    margin: 20px;
  }

  .admin-form {
    padding: 24px 20px;
  }

  .pagination {
    gap: 4px;
  }

  .pagination a,
  .pagination span {
    min-width: 36px;
    height: 36px;
    padding: 0 8px;
    font-size: 13px;
  }
}

/* ============================================================
   工具类
   ============================================================ */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }
.mt-20 { margin-top: 20px; }
.mb-20 { margin-bottom: 20px; }
.hidden { display: none !important; }
.flex { display: flex; }
.gap-12 { gap: 12px; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }

/* 状态标签 */
.status-badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 600;
}

.status-active {
  background: #ECFDF5;
  color: #059669;
}

.status-inactive {
  background: #FEF2F2;
  color: #DC2626;
}

/* 文件大小标签 */
.file-size {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  background: var(--gray-100);
  border-radius: var(--radius-sm);
  font-size: 12px;
  color: var(--gray-600);
  font-weight: 500;
}