/* dida365NEW · bg.css — 全页固定背景层（极光 + 网格 + 粒子网络）
   仅供 index.html / mode.html 引入；类名 ddbg- 前缀，与页面原有样式零冲突 */

html{background:#0b1322}
body{background:transparent !important}

.ddbg-layer{position:fixed;inset:0;z-index:-1;pointer-events:none;overflow:hidden;background:#0b1322}

/* 网格底纹（缓慢呼吸） */
.ddbg-grid{position:absolute;inset:0;opacity:.5;
  background-image:linear-gradient(rgba(255,255,255,.04) 1px,transparent 1px),
    linear-gradient(90deg,rgba(255,255,255,.04) 1px,transparent 1px);
  background-size:54px 54px;
  animation:ddbgGridPulse 9s ease-in-out infinite;
  will-change:opacity,background-position}
@keyframes ddbgGridPulse{0%,100%{opacity:.4;background-position:0 0,0 0}50%{opacity:.85;background-position:14px 14px,14px 14px}}

/* 极光：深蔚蓝 + 香槟金 双辉 */
.ddbg-aurora{position:absolute;inset:-15%;filter:blur(12px)}
.ddbg-aurora::before,.ddbg-aurora::after{content:'';position:absolute;border-radius:50%;mix-blend-mode:screen;will-change:transform,opacity}
.ddbg-aurora::before{width:62vw;height:62vw;left:4%;top:-8%;
  background:radial-gradient(circle,rgba(44,82,130,.55),transparent 62%);
  animation:ddbgAuroraA 22s ease-in-out infinite}
.ddbg-aurora::after{width:50vw;height:50vw;right:0;bottom:-12%;
  background:radial-gradient(circle,rgba(200,155,60,.20),transparent 60%);
  animation:ddbgAuroraB 26s ease-in-out infinite}
@keyframes ddbgAuroraA{0%,100%{transform:translate(0,0) scale(1);opacity:.85}50%{transform:translate(7%,5%) scale(1.18);opacity:1}}
@keyframes ddbgAuroraB{0%,100%{transform:translate(0,0) scale(1);opacity:.7}50%{transform:translate(-6%,-7%) scale(1.22);opacity:1}}

#ddbgCanvas{position:absolute;inset:0;width:100%;height:100%}

/* 原版 #pageBg 背景层由 ddbg 层接管，隐藏避免重复叠加 */
#pageBg{display:none !important}

@media (prefers-reduced-motion:reduce){
  .ddbg-grid,.ddbg-aurora::before,.ddbg-aurora::after{animation:none !important}
}