/* 暗色模式 — 保持原有背景图 */
html, body {
  background: url(/bg-dark.png) no-repeat center center fixed !important;
  background-size: cover !important;
}

/* 浅色模式 — CSS 玻璃艺术壁纸（柔和光晕渐变） */
[data-theme="light"] html,
[data-theme="light"] body {
  background:
    radial-gradient(ellipse at 20% 50%, rgba(200,220,255,0.35) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 20%, rgba(230,240,255,0.45) 0%, transparent 50%),
    radial-gradient(ellipse at 50% 80%, rgba(240,235,255,0.35) 0%, transparent 50%),
    linear-gradient(180deg, #f8f9ff 0%, #f0f2f8 50%, #eef0f5 100%) !important;
  background-attachment: fixed !important;
}

/* iOS Safari 修复：fixed 背景在 iOS 上卡顿，改为 scroll */
@supports (-webkit-touch-callout: none) {
  html, body {
    background-attachment: scroll !important;
  }
}