/* 侧边栏目录图标：实心 SVG，background-image 直接渲染（可靠），日/夜两套色由 html.dark-mode 切换
   - folder 项（技术汇总等无链接目录）：标题是 li 的文本节点（无 a），图标做在 li::before（inline-block + vertical-align:middle 对齐文本）
   - file 项（首页等有链接叶子）：图标做在 a::before + a flex 居中 */
.sidebar-nav>ul{margin-left:20px}
.sidebar-nav ul:not(.app-sub-sidebar)>li{position:relative;margin:0;cursor:pointer;margin-left:4px}

/* folder 项：标题是文本节点无 a，图标做在 li::before inline-block 与文本同行 */
.sidebar-nav ul:not(.app-sub-sidebar)>li.folder::before{
  content:'';display:inline-block;vertical-align:middle;
  width:14px;height:14px;margin-right:8px;
  background-repeat:no-repeat;background-position:center;background-size:contain;
  background-image:url(data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAyNCAyNCI+PHBhdGggZmlsbD0iIzI1Nzk4QSIgZD0iTTkuNSA0IDggNS41SDRjLTEuMSAwLTIgLjktMiAyVjE4YzAgMS4xLjkgMiAyIDJoMTZjMS4xIDAgMi0uOSAyLTJWNmMwLTEuMS0uOS0yLTItMkg5LjV6Ii8+PC9zdmc+);
}
html.dark-mode .sidebar-nav ul:not(.app-sub-sidebar)>li.folder::before{background-image:url(data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAyNCAyNCI+PHBhdGggZmlsbD0iIzRGQjhDOSIgZD0iTTkuNSA0IDggNS41SDRjLTEuMSAwLTIgLjktMiAyVjE4YzAgMS4xLjkgMiAyIDJoMTZjMS4xIDAgMi0uOSAyLTJWNmMwLTEuMS0uOS0yLTItMkg5LjV6Ii8+PC9zdmc+)}

/* file 项：a flex 居中，图标在 a::before */
.sidebar-nav ul:not(.app-sub-sidebar)>li.file>a{display:flex;align-items:center;gap:8px}
.sidebar-nav ul:not(.app-sub-sidebar)>li.file>a::before{
  content:'';display:block;flex:0 0 14px;height:14px;width:14px;
  background-repeat:no-repeat;background-position:center;background-size:contain;
  background-image:url(data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAyNCAyNCI+PHBhdGggZmlsbD0iIzI1Nzk4QSIgZmlsbC1ydWxlPSJldmVub2RkIiBkPSJNNiAyYy0xLjEgMC0yIC45LTIgMnYxNmMwIDEuMS45IDIgMiAyaDEyYzEuMSAwIDItLjkgMi0yVjhsLTYtNkg2em04IDEuNUwxOC41IDhIMTRWMy41ek02IDRoNnY2aDZ2MTBINlY0eiIvPjwvc3ZnPg==);
}
html.dark-mode .sidebar-nav ul:not(.app-sub-sidebar)>li.file>a::before{background-image:url(data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAyNCAyNCI+PHBhdGggZmlsbD0iIzRGQjhDOSIgZmlsbC1ydWxlPSJldmVub2RkIiBkPSJNNiAyYy0xLjEgMC0yIC45LTIgMnYxNmMwIDEuMS45IDIgMiAyaDEyYzEuMSAwIDItLjkgMi0yVjhsLTYtNkg2em04IDEuNUwxOC41IDhIMTRWMy41ek02IDRoNnY2aDZ2MTBINlY0eiIvPjwvc3ZnPg==)}