/* 全局样式由内联CSS和UI_CLASS控制 */
.video-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}

.main-nav a {
  position: relative;
}

.main-nav a::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: #e74c3c;
  transition: width 0.3s;
}

.main-nav a:hover::after {
  width: 100%;
}

/* UI样式变体 */
.ui-style-0 { --theme-color: #e74c3c; }
.ui-style-1 { --theme-color: #3498db; }
.ui-style-2 { --theme-color: #2ecc71; }
.ui-style-3 { --theme-color: #f39c12; }
.ui-style-4 { --theme-color: #9b59b6; }
.ui-style-5 { --theme-color: #1abc9c; }
.ui-style-6 { --theme-color: #e67e22; }
.ui-style-7 { --theme-color: #34495e; }
.ui-style-8 { --theme-color: #16a085; }
.ui-style-9 { --theme-color: #c0392b; }
.ui-style-10 { --theme-color: #2980b9; }
.ui-style-11 { --theme-color: #8e44ad; }
.ui-style-12 { --theme-color: #27ae60; }
.ui-style-13 { --theme-color: #d35400; }
.ui-style-14 { --theme-color: #7f8c8d; }
.ui-style-15 { --theme-color: #c72c41; }