/* 补充 E.3：首屏启动屏占位（Logo + 加载动画），Vue 挂载后由 main.ts 淡出移除。
   作为独立文件经 index.html 的 <link> 引用，保证在 JS/CSS 打包前即可渲染，缩短白屏。 */
#splash {
  position: fixed;
  inset: 0;
  z-index: 99999;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 18px;
  background: linear-gradient(160deg, #fff7e9 0%, #ffe9c7 100%);
  transition: opacity 0.4s ease;
}
#splash.hide { opacity: 0; pointer-events: none; }
#splash .splash-logo {
  width: 96px;
  height: 96px;
  border-radius: 26px;
  background: #fff;
  box-shadow: 0 12px 30px rgba(255, 140, 66, 0.35);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 56px;
  animation: splash-pop 0.9s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}
#splash .splash-name {
  font-size: 18px;
  font-weight: 800;
  color: #ff8c42;
  letter-spacing: 1px;
}
#splash .splash-spinner {
  width: 30px;
  height: 30px;
  border: 4px solid rgba(255, 140, 66, 0.25);
  border-top-color: #ff8c42;
  border-radius: 50%;
  animation: splash-spin 0.8s linear infinite;
}
@keyframes splash-pop {
  from { transform: scale(0.4); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}
@keyframes splash-spin { to { transform: rotate(360deg); } }