/* 下载卡片 */
.download-card { transition: transform 0.25s ease, box-shadow 0.25s ease; }
.download-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 40px -12px rgba(99,102,241,0.2);
}
.dark .download-card:hover {
  box-shadow: 0 20px 40px -12px rgba(0,0,0,0.5);
}

/* 淡入上升动画 */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}
.fade-up   { animation: fadeUp 0.6s ease forwards; }
.delay-100 { animation-delay: 0.1s; opacity: 0; }
.delay-200 { animation-delay: 0.2s; opacity: 0; }
.delay-300 { animation-delay: 0.3s; opacity: 0; }