:root{
  --primary:#3370FF; --primary-dark:#2456d6; --primary-light:#eef3ff;
  --ink:#1f2329; --ink-2:#4e5969; --ink-3:#86909c;
  --line:#e5e6eb; --bg:#f5f6f7; --card:#ffffff;
  --sidebar-w:250px; --topbar-h:58px;
  --shadow:0 2px 12px rgba(31,35,41,.06);
  --shadow-lg:0 10px 30px rgba(31,35,41,.12);
}
*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;
  color:var(--ink);background:var(--bg);-webkit-font-smoothing:antialiased;}

.app{display:flex;min-height:100vh}

/* ---------- 侧边栏 ---------- */
.sidebar{
  width:var(--sidebar-w);flex:none;background:var(--card);border-right:1px solid var(--line);
  display:flex;flex-direction:column;position:fixed;top:0;bottom:0;left:0;z-index:60;
}
.brand{display:flex;align-items:center;gap:11px;padding:18px 18px 14px;}
.brand-logo{width:38px;height:38px;border-radius:10px;background:linear-gradient(135deg,#3370FF,#5b8cff);
  color:#fff;font-size:19px;font-weight:700;display:flex;align-items:center;justify-content:center;flex:none;
  box-shadow:0 4px 10px rgba(51,112,255,.35)}
.brand-name{font-size:16px;font-weight:700;line-height:1.2}
.brand-sub{font-size:11.5px;color:var(--ink-3);margin-top:2px}

.search{padding:4px 14px 10px}
.search input{width:100%;height:36px;border:1px solid var(--line);border-radius:9px;padding:0 12px;
  font-size:13.5px;background:var(--bg);outline:none;transition:.15s}
.search input:focus{border-color:var(--primary);background:#fff;box-shadow:0 0 0 3px rgba(51,112,255,.12)}

.nav{flex:1;overflow-y:auto;padding:2px 10px 12px}
.nav-group{margin-bottom:6px}
.nav-group-title{font-size:11.5px;color:var(--ink-3);font-weight:600;letter-spacing:.3px;
  padding:10px 10px 5px}
.nav-item{display:flex;align-items:center;gap:9px;width:100%;border:none;background:none;
  text-align:left;padding:8px 10px;border-radius:8px;font-size:14px;color:var(--ink-2);cursor:pointer;
  transition:.12s;line-height:1.3}
.nav-item:hover{background:var(--primary-light);color:var(--primary-dark)}
.nav-item.active{background:var(--primary);color:#fff;font-weight:600}
.nav-item .dot{width:7px;height:7px;border-radius:50%;background:currentColor;opacity:.5;flex:none}
.nav-item .star{margin-left:auto;font-size:11px;color:var(--primary)}
.nav-item.active .star{color:#fff}

.sidebar-foot{padding:12px 14px;border-top:1px solid var(--line)}
.btn-hr{width:100%;height:38px;border:1px solid var(--primary);background:var(--primary-light);
  color:var(--primary-dark);border-radius:9px;font-size:13.5px;font-weight:600;cursor:pointer}
.btn-hr:hover{background:var(--primary);color:#fff}

/* ---------- 主区域 ---------- */
.main{flex:1;margin-left:var(--sidebar-w);display:flex;flex-direction:column;min-width:0}
.topbar{height:var(--topbar-h);background:var(--card);border-bottom:1px solid var(--line);
  display:flex;align-items:center;gap:12px;padding:0 20px;position:sticky;top:0;z-index:40}
.crumb{font-size:15px;font-weight:600;flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.top-right{display:flex;align-items:center;gap:12px}
.icon-btn{border:none;background:none;cursor:pointer;color:var(--ink-2);font-size:18px;
  width:36px;height:36px;border-radius:8px;display:flex;align-items:center;justify-content:center}
.icon-btn:hover{background:var(--bg)}
.menu-btn{display:none;flex-direction:column;gap:4px;align-items:center;justify-content:center}
.menu-btn span{width:18px;height:2px;background:var(--ink);border-radius:2px}

.user{display:flex;align-items:center;gap:8px}
.avatar{width:32px;height:32px;border-radius:50%;background:var(--primary);color:#fff;
  display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:600;overflow:hidden}
.avatar img{width:100%;height:100%;object-fit:cover}
.user-name{font-size:13.5px;color:var(--ink-2);max-width:120px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}

.content{flex:1;position:relative;min-height:0}
.home{padding:28px 30px 60px;max-width:1180px;margin:0 auto}
.welcome h1{font-size:23px;margin:6px 0 8px}
.welcome p{color:var(--ink-2);font-size:14.5px;margin:0 0 24px}

.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:18px}
.cat-card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:20px 22px;
  box-shadow:var(--shadow);cursor:pointer;transition:.18s}
.cat-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg);border-color:var(--primary)}
.cat-head{display:flex;align-items:center;gap:12px;margin-bottom:14px}
.cat-icon{width:42px;height:42px;border-radius:11px;background:var(--primary-light);color:var(--primary);
  display:flex;align-items:center;justify-content:center;font-size:20px;flex:none}
.cat-title{font-size:16px;font-weight:700}
.cat-list{list-style:none;margin:0;padding:0}
.cat-list li{font-size:13.5px;color:var(--ink-2);padding:5px 0 5px 14px;position:relative}
.cat-list li::before{content:"";position:absolute;left:0;top:13px;width:5px;height:5px;border-radius:50%;
  background:var(--ink-3)}
.cat-list li.more{color:var(--primary);font-weight:600}

.frame{width:100%;height:calc(100vh - var(--topbar-h));border:none;background:#fff;display:block}

.mask{display:none;position:fixed;inset:0;background:rgba(0,0,0,.4);z-index:50}

/* ---------- 移动端 ---------- */
@media (max-width:860px){
  .sidebar{transform:translateX(-100%);transition:transform .25s;box-shadow:var(--shadow-lg)}
  .sidebar.open{transform:translateX(0)}
  .mask.show{display:block}
  .main{margin-left:0}
  .menu-btn{display:flex}
  .user-name{display:none}
  .home{padding:20px 16px 50px}
  .frame{height:calc(100vh - var(--topbar-h))}
  .cards{grid-template-columns:1fr}
}