:root{--bg:#eef3f8;--panel:#fff;--ink:#172235;--muted:#718096;--blue:#2878ff;--cyan:#20c7d9;--line:#dce5ef;--shadow:0 12px 32px rgba(32,64,96,.09)}*{box-sizing:border-box}body{margin:0;font-family:Inter,"PingFang SC","Microsoft YaHei",sans-serif;background:var(--bg);color:var(--ink);overflow-x:hidden;-webkit-user-select:none;user-select:none;-webkit-touch-callout:none}button{-webkit-user-select:none;user-select:none;-webkit-touch-callout:none;-webkit-tap-highlight-color:transparent}.topbar{height:72px;background:#fff;display:flex;align-items:center;padding:0 28px;border-bottom:1px solid var(--line);gap:38px}.brand{display:flex;align-items:center;gap:11px;min-width:240px}.logo{width:42px;height:42px;border-radius:13px;background:linear-gradient(145deg,var(--blue),#6c4cff);color:#fff;display:grid;place-items:center;font-size:24px;font-weight:900;box-shadow:0 7px 18px rgba(40,120,255,.25)}.brand strong,.brand span{display:block}.brand strong{font-size:18px}.brand span{font-size:10px;letter-spacing:1.7px;color:#7b8aa0;margin-top:2px}.topbar nav{display:flex;align-self:stretch}.nav-item{border:0;background:transparent;padding:0 25px;font-weight:700;color:#7d8999;position:relative}.nav-item.active{color:var(--blue)}.nav-item.active:after{content:"";position:absolute;height:3px;border-radius:3px;background:var(--blue);left:19px;right:19px;bottom:0}.nav-item small{display:block;font-size:8px;font-weight:500}.topbar .ghost{margin-left:auto;border:1px solid var(--line);background:#fff;border-radius:10px;padding:10px 16px;color:#59677a;font-weight:600;cursor:pointer}.app-shell{height:calc(100vh - 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