/**
 * DAF学院 - 现代化设计系统
 * Version: 2.0
 * 采用 CSS Custom Properties 实现主题化设计
 */

/* ========================================
   1. CSS Variables - 设计令牌
======================================== */
:root {
  /* 主色调 - 深蓝游戏风格 */
  --color-primary: #3a7bd5;
  --color-primary-light: #5a9bf0;
  --color-primary-dark: #2a5aa5;
  --color-primary-50: rgba(58, 123, 213, 0.1);
  --color-primary-100: rgba(58, 123, 213, 0.2);
  
  /* 强调色 - 金色/橙色 */
  --color-accent: #f5a623;
  --color-accent-light: #ffc65c;
  --color-accent-dark: #d88d1a;
  
  /* 功能色 */
  --color-success: #00c853;
  --color-success-bg: rgba(0, 200, 83, 0.1);
  --color-warning: #ff9800;
  --color-warning-bg: rgba(255, 152, 0, 0.1);
  --color-danger: #f44336;
  --color-danger-bg: rgba(244, 67, 54, 0.1);
  --color-info: #2196f3;
  --color-info-bg: rgba(33, 150, 243, 0.1);
  
  /* 中性色 */
  --color-gray-50: #fafafa;
  --color-gray-100: #f5f5f5;
  --color-gray-200: #eeeeee;
  --color-gray-300: #e0e0e0;
  --color-gray-400: #bdbdbd;
  --color-gray-500: #9e9e9e;
  --color-gray-600: #757575;
  --color-gray-700: #616161;
  --color-gray-800: #424242;
  --color-gray-900: #212121;
  
  /* 背景色 */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  --bg-dark: #1a1a2e;
  --bg-card: #ffffff;
  --bg-overlay: rgba(0, 0, 0, 0.5);
  
  /* 文字颜色 */
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --text-tertiary: #94a3b8;
  --text-inverse: #ffffff;
  --text-link: var(--color-primary);
  --text-link-hover: var(--color-primary-dark);
  
  /* 边框 */
  --border-color: #e2e8f0;
  --border-color-light: #f1f5f9;
  --border-color-dark: #cbd5e1;
  --border-radius-sm: 4px;
  --border-radius: 8px;
  --border-radius-lg: 12px;
  --border-radius-xl: 16px;
  --border-radius-full: 9999px;
  
  /* 阴影 */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  
  /* 间距 */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-2xl: 48px;
  --spacing-3xl: 64px;
  
  /* 字体 - 使用系统字体栈，无需外部加载 */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
  --font-family-mono: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  
  /* 字号 */
  --font-size-xs: 12px;
  --font-size-sm: 14px;
  --font-size-base: 16px;
  --font-size-lg: 18px;
  --font-size-xl: 20px;
  --font-size-2xl: 24px;
  --font-size-3xl: 30px;
  --font-size-4xl: 36px;
  
  /* 行高 */
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;
  
  /* 字重 */
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* 过渡动画 */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 350ms ease;
  --transition-bounce: 350ms cubic-bezier(0.68, -0.55, 0.265, 1.55);
  
  /* z-index 层级 */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal-backdrop: 400;
  --z-modal: 500;
  --z-popover: 600;
  --z-tooltip: 700;
  
  /* 布局 */
  --container-max-width: 1400px;
  --header-height: 64px;
  --sidebar-width: 280px;
}

/* 深色主题 */
[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --bg-card: #1e293b;
  
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-tertiary: #64748b;
  
  --border-color: #334155;
  --border-color-light: #1e293b;
  --border-color-dark: #475569;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.4), 0 1px 2px -1px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -2px rgba(0, 0, 0, 0.4);
}

/* ========================================
   2. Reset & Base Styles
======================================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--text-primary);
  background-color: var(--bg-secondary);
  min-height: 100vh;
}

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

a:hover {
  color: var(--text-link-hover);
}

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

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

ul, ol {
  list-style: none;
}

/* ========================================
   3. 布局系统
======================================== */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.container-fluid {
  width: 100%;
  padding: 0 var(--spacing-md);
}

/* Flexbox 工具类 */
.flex { display: flex; }
.inline-flex { display: inline-flex; }
.flex-col { flex-direction: column; }
.flex-row { flex-direction: row; }
.flex-wrap { flex-wrap: wrap; }
.items-start { align-items: flex-start; }
.items-center { align-items: center; }
.items-end { align-items: flex-end; }
.items-stretch { align-items: stretch; }
.justify-start { justify-content: flex-start; }
.justify-center { justify-content: center; }
.justify-end { justify-content: flex-end; }
.justify-between { justify-content: space-between; }
.justify-around { justify-content: space-around; }
.gap-xs { gap: var(--spacing-xs); }
.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }
.gap-xl { gap: var(--spacing-xl); }
.flex-1 { flex: 1; }
.flex-auto { flex: auto; }
.flex-none { flex: none; }

/* Grid 系统 */
.grid { display: grid; }
.grid-cols-1 { grid-template-columns: repeat(1, minmax(0, 1fr)); }
.grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid-cols-12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }

/* ========================================
   4. 间距工具类
======================================== */
.p-0 { padding: 0; }
.p-xs { padding: var(--spacing-xs); }
.p-sm { padding: var(--spacing-sm); }
.p-md { padding: var(--spacing-md); }
.p-lg { padding: var(--spacing-lg); }
.p-xl { padding: var(--spacing-xl); }

.px-xs { padding-left: var(--spacing-xs); padding-right: var(--spacing-xs); }
.px-sm { padding-left: var(--spacing-sm); padding-right: var(--spacing-sm); }
.px-md { padding-left: var(--spacing-md); padding-right: var(--spacing-md); }
.px-lg { padding-left: var(--spacing-lg); padding-right: var(--spacing-lg); }

.py-xs { padding-top: var(--spacing-xs); padding-bottom: var(--spacing-xs); }
.py-sm { padding-top: var(--spacing-sm); padding-bottom: var(--spacing-sm); }
.py-md { padding-top: var(--spacing-md); padding-bottom: var(--spacing-md); }
.py-lg { padding-top: var(--spacing-lg); padding-bottom: var(--spacing-lg); }

.m-0 { margin: 0; }
.m-auto { margin: auto; }
.mx-auto { margin-left: auto; margin-right: auto; }
.mb-xs { margin-bottom: var(--spacing-xs); }
.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }
.mt-xs { margin-top: var(--spacing-xs); }
.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }

/* ========================================
   5. 文字排版
======================================== */
.text-xs { font-size: var(--font-size-xs); }
.text-sm { font-size: var(--font-size-sm); }
.text-base { font-size: var(--font-size-base); }
.text-lg { font-size: var(--font-size-lg); }
.text-xl { font-size: var(--font-size-xl); }
.text-2xl { font-size: var(--font-size-2xl); }
.text-3xl { font-size: var(--font-size-3xl); }
.text-4xl { font-size: var(--font-size-4xl); }

.font-normal { font-weight: var(--font-weight-normal); }
.font-medium { font-weight: var(--font-weight-medium); }
.font-semibold { font-weight: var(--font-weight-semibold); }
.font-bold { font-weight: var(--font-weight-bold); }

.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }

.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-tertiary { color: var(--text-tertiary); }
.text-accent { color: var(--color-accent); }
.text-success { color: var(--color-success); }
.text-warning { color: var(--color-warning); }
.text-danger { color: var(--color-danger); }
.text-info { color: var(--color-info); }

.truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.line-clamp-2 {
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.line-clamp-3 {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ========================================
   6. 按钮组件
======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  line-height: 1.5;
  border-radius: var(--border-radius);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
  user-select: none;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.btn-sm {
  padding: var(--spacing-xs) var(--spacing-sm);
  font-size: var(--font-size-xs);
}

.btn-lg {
  padding: var(--spacing-md) var(--spacing-lg);
  font-size: var(--font-size-base);
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  color: var(--text-inverse);
  border-color: var(--color-primary);
  box-shadow: 0 2px 4px rgba(58, 123, 213, 0.3);
}

.btn-primary:hover:not(:disabled) {
  background: linear-gradient(135deg, var(--color-primary-light) 0%, var(--color-primary) 100%);
  box-shadow: 0 4px 8px rgba(58, 123, 213, 0.4);
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--bg-primary);
  color: var(--text-primary);
  border-color: var(--border-color);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--bg-tertiary);
  border-color: var(--border-color-dark);
}

.btn-accent {
  background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-dark) 100%);
  color: var(--text-inverse);
  border-color: var(--color-accent);
  box-shadow: 0 2px 4px rgba(245, 166, 35, 0.3);
}

.btn-accent:hover:not(:disabled) {
  background: linear-gradient(135deg, var(--color-accent-light) 0%, var(--color-accent) 100%);
  box-shadow: 0 4px 8px rgba(245, 166, 35, 0.4);
  transform: translateY(-1px);
}

.btn-success {
  background: var(--color-success);
  color: var(--text-inverse);
  border-color: var(--color-success);
}

.btn-success:hover:not(:disabled) {
  background: #00b548;
  box-shadow: 0 4px 8px rgba(0, 200, 83, 0.3);
}

.btn-danger {
  background: var(--color-danger);
  color: var(--text-inverse);
  border-color: var(--color-danger);
}

.btn-danger:hover:not(:disabled) {
  background: #e53935;
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border-color: transparent;
}

.btn-ghost:hover:not(:disabled) {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.btn-link {
  background: transparent;
  color: var(--text-link);
  border-color: transparent;
  padding: 0;
}

.btn-link:hover:not(:disabled) {
  color: var(--text-link-hover);
  text-decoration: underline;
}

.btn-icon {
  padding: var(--spacing-sm);
  aspect-ratio: 1;
}

/* ========================================
   7. 卡片组件
======================================== */
.card {
  background: var(--bg-card);
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--border-color-light);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
  overflow: hidden;
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card-clickable:hover {
  transform: translateY(-2px);
  cursor: pointer;
}

.card-header {
  padding: var(--spacing-md) var(--spacing-lg);
  border-bottom: 1px solid var(--border-color-light);
  background: var(--bg-tertiary);
}

.card-body {
  padding: var(--spacing-lg);
}

.card-footer {
  padding: var(--spacing-md) var(--spacing-lg);
  border-top: 1px solid var(--border-color-light);
  background: var(--bg-gray-50);
}

/* ========================================
   8. 表单组件
======================================== */
.form-group {
  margin-bottom: var(--spacing-md);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--text-secondary);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  font-size: var(--font-size-sm);
  line-height: 1.5;
  color: var(--text-primary);
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-50);
}

.form-input::placeholder {
  color: var(--text-tertiary);
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

.form-input-error {
  border-color: var(--color-danger);
}

.form-input-error:focus {
  box-shadow: 0 0 0 3px var(--color-danger-bg);
}

.form-error {
  margin-top: var(--spacing-xs);
  font-size: var(--font-size-xs);
  color: var(--color-danger);
}

.form-help {
  margin-top: var(--spacing-xs);
  font-size: var(--font-size-xs);
  color: var(--text-tertiary);
}

/* ========================================
   9. 徽章和标签
======================================== */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px var(--spacing-sm);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-medium);
  line-height: 1.5;
  border-radius: var(--border-radius-full);
  white-space: nowrap;
}

.badge-primary {
  background: var(--color-primary-100);
  color: var(--color-primary-dark);
}

.badge-success {
  background: var(--color-success-bg);
  color: var(--color-success);
}

.badge-warning {
  background: var(--color-warning-bg);
  color: var(--color-warning);
}

.badge-danger {
  background: var(--color-danger-bg);
  color: var(--color-danger);
}

.badge-info {
  background: var(--color-info-bg);
  color: var(--color-info);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-xs) var(--spacing-sm);
  font-size: var(--font-size-xs);
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  border-radius: var(--border-radius-sm);
}

.tag-hot {
  background: linear-gradient(135deg, #ff6b6b 0%, #ee5a5a 100%);
  color: white;
}

.tag-new {
  background: linear-gradient(135deg, #4ecdc4 0%, #44a08d 100%);
  color: white;
}

.tag-vip {
  background: linear-gradient(135deg, #f5a623 0%, #e09612 100%);
  color: white;
}

.tag-reward {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

/* ========================================
   10. 头像组件
======================================== */
.avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--border-radius-full);
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  font-weight: var(--font-weight-medium);
  overflow: hidden;
  flex-shrink: 0;
}

.avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.avatar-xs { width: 24px; height: 24px; font-size: 10px; }
.avatar-sm { width: 32px; height: 32px; font-size: 12px; }
.avatar-md { width: 40px; height: 40px; font-size: 14px; }
.avatar-lg { width: 48px; height: 48px; font-size: 16px; }
.avatar-xl { width: 64px; height: 64px; font-size: 20px; }
.avatar-2xl { width: 96px; height: 96px; font-size: 28px; }

.avatar-group {
  display: flex;
}

.avatar-group .avatar {
  border: 2px solid var(--bg-primary);
  margin-left: -8px;
}

.avatar-group .avatar:first-child {
  margin-left: 0;
}

/* ========================================
   11. 分页组件
======================================== */
.pagination {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  flex-wrap: wrap;
}

.pagination-item {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  height: 36px;
  padding: 0 var(--spacing-sm);
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.pagination-item:hover:not(.active):not(.disabled) {
  color: var(--color-primary);
  border-color: var(--color-primary);
  background: var(--color-primary-50);
}

.pagination-item.active {
  color: var(--text-inverse);
  background: var(--color-primary);
  border-color: var(--color-primary);
}

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

/* ========================================
   12. 加载动画
======================================== */
.spinner {
  width: 24px;
  height: 24px;
  border: 2px solid var(--border-color);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.spinner-sm { width: 16px; height: 16px; border-width: 2px; }
.spinner-lg { width: 32px; height: 32px; border-width: 3px; }

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

.skeleton {
  background: linear-gradient(90deg, var(--bg-tertiary) 25%, var(--bg-secondary) 50%, var(--bg-tertiary) 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: var(--border-radius-sm);
}

@keyframes skeleton-loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ========================================
   13. 弹窗和模态框
======================================== */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: var(--bg-overlay);
  z-index: var(--z-modal-backdrop);
  opacity: 0;
  pointer-events: none;
  display: none;
  transition: opacity var(--transition-normal);
}

.modal-backdrop.active {
  opacity: 1;
  pointer-events: auto;
  display: block;
}

.modal {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0.95);
  background: var(--bg-card);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-xl);
  z-index: var(--z-modal);
  max-width: 90vw;
  max-height: 90vh;
  opacity: 0;
  pointer-events: none;
  display: none;
  overflow: auto;
  opacity: 0;
  transition: all var(--transition-normal);
}

.modal.active {
  opacity: 1;
  pointer-events: auto;
  display: block;
  transform: translate(-50%, -50%) scale(1);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) var(--spacing-lg);
  border-bottom: 1px solid var(--border-color-light);
}

.modal-title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
}

.modal-close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: none;
  background: transparent;
  color: var(--text-tertiary);
  cursor: pointer;
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
}

.modal-close:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.modal-body {
  padding: var(--spacing-lg);
}

.modal-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-lg);
  border-top: 1px solid var(--border-color-light);
}

/* ========================================
   14. Toast 提示
======================================== */
.toast-container {
  position: fixed;
  top: var(--spacing-lg);
  right: var(--spacing-lg);
  z-index: var(--z-tooltip);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.toast {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-lg);
  background: var(--bg-card);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-lg);
  border-left: 4px solid var(--color-info);
  min-width: 300px;
  max-width: 450px;
  animation: toast-slide-in 0.3s ease;
}

.toast-success { border-left-color: var(--color-success); }
.toast-warning { border-left-color: var(--color-warning); }
.toast-danger { border-left-color: var(--color-danger); }

@keyframes toast-slide-in {
  from {
    opacity: 0;
    transform: translateX(100%);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* ========================================
   15. 工具提示
======================================== */
.tooltip {
  position: relative;
}

.tooltip::before,
.tooltip::after {
  position: absolute;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-fast);
  pointer-events: none;
}

.tooltip::before {
  content: attr(data-tooltip);
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  padding: var(--spacing-xs) var(--spacing-sm);
  background: var(--color-gray-800);
  color: var(--text-inverse);
  font-size: var(--font-size-xs);
  border-radius: var(--border-radius-sm);
  white-space: nowrap;
  z-index: var(--z-tooltip);
}

.tooltip::after {
  content: '';
  bottom: calc(100% + 4px);
  left: 50%;
  transform: translateX(-50%);
  border: 4px solid transparent;
  border-top-color: var(--color-gray-800);
}

.tooltip:hover::before,
.tooltip:hover::after {
  opacity: 1;
  visibility: visible;
}

/* ========================================
   16. 进度条
======================================== */
.progress {
  height: 8px;
  background: var(--bg-tertiary);
  border-radius: var(--border-radius-full);
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  border-radius: var(--border-radius-full);
  transition: width var(--transition-normal);
}

.progress-sm { height: 4px; }
.progress-lg { height: 12px; }

/* ========================================
   17. 分割线
======================================== */
.divider {
  height: 1px;
  background: var(--border-color);
  margin: var(--spacing-md) 0;
}

.divider-vertical {
  width: 1px;
  height: 100%;
  background: var(--border-color);
  margin: 0 var(--spacing-md);
}

/* ========================================
   18. 响应式工具类
======================================== */
.hidden { display: none !important; }
.block { display: block; }
.inline-block { display: inline-block; }
.overflow-hidden { overflow: hidden; }
.overflow-auto { overflow: auto; }
.w-full { width: 100%; }
.h-full { height: 100%; }
.min-h-screen { min-height: 100vh; }

/* 响应式断点 */
@media (max-width: 640px) {
  .sm\:hidden { display: none !important; }
  .sm\:block { display: block !important; }
  .sm\:flex { display: flex !important; }
  .sm\:flex-col { flex-direction: column !important; }
  .sm\:text-center { text-align: center !important; }
  .sm\:w-full { width: 100% !important; }
}

@media (min-width: 641px) and (max-width: 1024px) {
  .md\:hidden { display: none !important; }
  .md\:block { display: block !important; }
  .md\:flex { display: flex !important; }
}

@media (min-width: 1025px) {
  .lg\:hidden { display: none !important; }
  .lg\:block { display: block !important; }
  .lg\:flex { display: flex !important; }
}

/* 移动端隐藏 */
@media (max-width: 768px) {
  .mobile-hidden { display: none !important; }
  .mobile-block { display: block !important; }
  .mobile-flex { display: flex !important; }
}

/* PC端隐藏 */
@media (min-width: 769px) {
  .pc-hidden { display: none !important; }
  .pc-block { display: block !important; }
}

/* ========================================
   19. 动画效果
======================================== */
.animate-fade-in {
  animation: fade-in 0.3s ease;
}

.animate-slide-up {
  animation: slide-up 0.3s ease;
}

.animate-slide-down {
  animation: slide-down 0.3s ease;
}

.animate-scale-in {
  animation: scale-in 0.3s ease;
}

.animate-bounce {
  animation: bounce 0.5s ease;
}

@keyframes fade-in {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slide-up {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slide-down {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-5px); }
}

/* 悬停动画 */
.hover-lift {
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.hover-lift:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.hover-scale {
  transition: transform var(--transition-fast);
}

.hover-scale:hover {
  transform: scale(1.02);
}

/* ========================================
   20. 特殊效果
======================================== */
/* 渐变文字 */
.gradient-text {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* 玻璃拟态效果 */
.glass {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

/* VIP 会员样式 */
.vip-badge {
  background: linear-gradient(135deg, #ffd700 0%, #ffb347 100%);
  color: #8b4513;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 12px;
  font-weight: 600;
}

.vip-border {
  border: 2px solid transparent;
  background: linear-gradient(var(--bg-card), var(--bg-card)) padding-box,
              linear-gradient(135deg, #ffd700, #ffb347, #ffd700) border-box;
}

/* 热门/精华帖子高亮 */
.post-highlight {
  position: relative;
  overflow: hidden;
}

.post-highlight::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(180deg, var(--color-accent) 0%, var(--color-danger) 100%);
}

/* 在线状态指示器 */
.status-indicator {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 2px solid var(--bg-card);
}

.status-online {
  background: var(--color-success);
  box-shadow: 0 0 0 2px rgba(0, 200, 83, 0.3);
}

.status-offline {
  background: var(--color-gray-400);
}

.status-busy {
  background: var(--color-danger);
}

/* ========================================
   21. 滚动条美化
======================================== */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-tertiary);
}

::-webkit-scrollbar-thumb {
  background: var(--color-gray-400);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-gray-500);
}

/* Firefox */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--color-gray-400) var(--bg-tertiary);
}

/* ========================================
   22. 打印样式
======================================== */
@media print {
  body {
    background: white;
    color: black;
  }
  
  .no-print {
    display: none !important;
  }
}