/* ==== 统一左菜单（usb-sidebar） — 按 需求.md §3 Figma 设计 ====
 * 视觉：260px 宽 / 亮蓝 140° 渐变 / 右上蓝光晕 + 左下青绿光晕 / 白文白 logo
 * 所有入口 .html 仅需在 body 头部放: <aside class="usb-sidebar"></aside>
 * 菜单数据由 sidebar.js 注入，由 部署.py 维护
 */
aside.usb-sidebar{
  width:260px;flex:0 0 260px;
  height:100vh;overflow:hidden;
  background:linear-gradient(140deg,#006AF1 0%,#0061DE 100%);
  color:#fff;
  font-family:"PingFang SC",-apple-system,BlinkMacSystemFont,"Microsoft YaHei",sans-serif;
  font-size:15px;line-height:1.4;
  display:flex;flex-direction:column;
  position:relative;
  -webkit-font-smoothing:antialiased;
  user-select:none;
  z-index:100;
}
aside.usb-sidebar *{box-sizing:border-box}
aside.usb-sidebar a{text-decoration:none;color:inherit}

/* 右上蓝光晕 + 左下青绿光晕（装饰层） */
aside.usb-sidebar::before{
  content:"";position:absolute;right:-150px;top:-90px;
  width:420px;height:420px;border-radius:50%;
  background:radial-gradient(circle,rgba(0,112,255,1) 0%,rgba(0,112,255,0) 70%);
  pointer-events:none;
}
aside.usb-sidebar::after{
  content:"";position:absolute;left:-200px;bottom:-180px;
  width:400px;height:400px;border-radius:50%;
  background:radial-gradient(circle,rgba(45,206,146,0.85) 0%,rgba(45,206,146,0.35) 50%,transparent 75%);
  pointer-events:none;
}
aside.usb-sidebar > *{position:relative;z-index:1}

/* Logo */
aside.usb-sidebar .u-logo{
  padding:18px 24px;display:flex;align-items:center;gap:10px;
  color:#fff;font-weight:600;font-size:18px;cursor:pointer;flex-shrink:0;
}
aside.usb-sidebar .u-logo .u-ic{
  width:30px;height:30px;border-radius:8px;background:#fff;color:#006EFB;
  display:inline-flex;align-items:center;justify-content:center;
  font-size:18px;font-weight:700;flex-shrink:0;
}
aside.usb-sidebar .u-menu{padding:6px 0 16px;flex:1;overflow-y:auto}
aside.usb-sidebar .u-menu::-webkit-scrollbar{width:4px}
aside.usb-sidebar .u-menu::-webkit-scrollbar-thumb{background:rgba(255,255,255,.2);border-radius:2px}

/* 一级 — 可展开组 */
aside.usb-sidebar .u-grp-title{
  display:flex;align-items:center;gap:14px;
  height:46px;margin:4px 12px;padding:0 16px;
  border-radius:8px;cursor:pointer;
  color:#fff;font-size:15px;font-weight:500;
  transition:background .15s;
}
aside.usb-sidebar .u-grp-title:hover{background:rgba(255,255,255,.12)}
aside.usb-sidebar .u-grp-title .u-ic{
  width:22px;height:22px;flex-shrink:0;
  display:inline-flex;align-items:center;justify-content:center;
  font-size:16px;
}
aside.usb-sidebar .u-grp-title .u-lb{
  flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;
}
aside.usb-sidebar .u-grp-title .u-ar{
  width:8px;height:8px;flex-shrink:0;
  border-right:1.5px solid rgba(255,255,255,.85);
  border-bottom:1.5px solid rgba(255,255,255,.85);
  transform:rotate(45deg);
  transition:transform .15s;
}
aside.usb-sidebar .u-grp.open .u-ar{transform:rotate(225deg);margin-top:4px}
aside.usb-sidebar .u-sub{display:none;padding:0 0 4px}
aside.usb-sidebar .u-grp.open .u-sub{display:block}

/* 二级条目 */
aside.usb-sidebar .u-it{
  display:flex;align-items:center;
  height:40px;margin:0 12px;padding-left:48px;
  border-radius:8px;
  color:rgba(255,255,255,.92);font-size:14px;
  position:relative;
  transition:background .15s,color .15s;
  overflow:hidden;text-overflow:ellipsis;white-space:nowrap;
}
aside.usb-sidebar .u-it::before{
  content:"";position:absolute;left:32px;top:50%;
  width:4px;height:4px;border-radius:50%;
  background:rgba(255,255,255,.75);transform:translateY(-50%);
}
aside.usb-sidebar .u-it:hover{background:rgba(255,255,255,.1)}
aside.usb-sidebar .u-it.active{background:#2183FF;color:#fff}
aside.usb-sidebar .u-it.active::before{background:#fff}

/* 一级 — 单页扁平 */
aside.usb-sidebar .u-flat{
  display:flex;align-items:center;gap:14px;
  height:46px;margin:4px 12px;padding:0 16px;
  border-radius:8px;
  color:#fff;font-size:15px;font-weight:500;
  transition:background .15s;
}
aside.usb-sidebar .u-flat:hover{background:rgba(255,255,255,.12)}
aside.usb-sidebar .u-flat.active{background:#2183FF}
aside.usb-sidebar .u-flat .u-ic{
  width:22px;height:22px;flex-shrink:0;
  display:inline-flex;align-items:center;justify-content:center;
  font-size:16px;
}
aside.usb-sidebar .u-flat .u-lb{
  flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;
}

/* 当组里含 active 子项时，组标题保持高亮 */
aside.usb-sidebar .u-grp:has(.u-it.active) .u-grp-title{background:rgba(255,255,255,.08)}

/* 入口页面 body 默认是 flex；若不是，强制让 sidebar 立柱 */
body:has(> aside.usb-sidebar){display:flex;margin:0}