:root{
  color-scheme:light;
  --bg:#fbfbfa;
  --surface:#ffffff;
  --line:#ececea;
  --ink:#15161a;
  --muted:#8a8d93;
  --soft:#f4f4f2;
  --accent:#1a1a1a;
  --radius:16px;
}
*{box-sizing:border-box}
html,body{margin:0}
body{
  font-family:ui-sans-serif,system-ui,-apple-system,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
  background:var(--bg);
  color:var(--ink);
  font-size:15px;
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
  min-height:100vh;
}
.hidden{display:none!important}
.muted{color:var(--muted);font-size:13.5px}
.hint{font-size:12.5px;color:var(--muted);margin-top:10px;min-height:16px;letter-spacing:.01em}
.row{display:flex;gap:10px;align-items:center}

/* 顶栏：极简 */
.topbar{
  display:flex;gap:20px;align-items:center;
  padding:22px 32px;max-width:1120px;margin:0 auto;
}
.brand{font-weight:600;font-size:15px;letter-spacing:.02em;flex:none}
.searchbox{flex:1;max-width:360px;margin-left:auto}
input,select,textarea{
  width:100%;padding:11px 16px;border-radius:999px;
  border:1px solid var(--line);background:var(--surface);color:var(--ink);
  font-size:14px;outline:none;transition:.18s;
}
input::placeholder{color:#b3b5ba}
input:focus{border-color:#cfcfcc;box-shadow:0 1px 2px rgba(0,0,0,.03)}
button{
  padding:11px 18px;border-radius:999px;border:0;background:var(--accent);color:#fff;
  font-size:14px;cursor:pointer;transition:.18s;letter-spacing:.01em;
}
button:hover{opacity:.88}
button.ghost{background:transparent;color:var(--muted);border:1px solid var(--line)}
button.ghost:hover{color:var(--ink);opacity:1;border-color:#dcdcd8}

/* 登入：留白越多越好 */
.gate{display:flex;align-items:center;justify-content:center;min-height:calc(100vh - 96px);padding:32px}
.gate-card{width:100%;max-width:400px;text-align:center}
.gate-card h1{font-size:22px;font-weight:600;margin:0 0 10px;letter-spacing:.01em}
.gate-card p{color:var(--muted);font-size:14px;margin:0 0 28px}
.gate-card .row{gap:10px}
#gateHint{margin-top:14px}

/* 主视觉：大留白 */
.hero{padding:72px 32px 40px;max-width:1120px;margin:0 auto}
.hero h1{font-size:34px;font-weight:650;letter-spacing:-.01em;margin:0 0 12px;line-height:1.2}
.hero p{color:var(--muted);font-size:14.5px;margin:0;letter-spacing:.02em}

/* 分类：文字标签 */
.tabs{
  display:flex;gap:28px;padding:18px 32px 8px;max-width:1120px;margin:0 auto;
  border-bottom:1px solid var(--line);
}
.tab{
  padding:0 0 14px;background:none;border:none;border-radius:0;
  color:var(--muted);font-size:14px;cursor:pointer;position:relative;transition:.18s;letter-spacing:.01em;
}
.tab:hover{color:var(--ink)}
.tab.active{color:var(--ink);font-weight:560}
.tab.active::after{
  content:"";position:absolute;left:0;right:0;bottom:-1px;height:2px;background:var(--ink);border-radius:2px;
}

/* 卡片：白底细边，呼吸感 */
.grid{
  display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));
  gap:20px;padding:36px 32px 72px;max-width:1120px;margin:0 auto;
}
.card{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px 24px;cursor:pointer;transition:transform .18s,box-shadow .18s,border-color .18s;
  display:flex;flex-direction:column;min-height:160px;
}
.card:hover{transform:translateY(-3px);box-shadow:0 12px 32px rgba(20,20,20,.06);border-color:#e2e2de}
.card .cat{
  display:inline-block;font-size:11px;letter-spacing:.06em;text-transform:uppercase;
  color:var(--muted);margin-bottom:14px;
}
.card h3{margin:0 0 10px;font-size:16.5px;font-weight:600;letter-spacing:.01em;line-height:1.4}
.card p{margin:0;color:var(--muted);font-size:13.5px;line-height:1.7}
.card .tags{margin-top:auto;padding-top:18px;display:flex;gap:8px;flex-wrap:wrap}
.card .tag{font-size:11.5px;color:#a3a5ab;background:var(--soft);border-radius:6px;padding:3px 8px}

/* 弹层 */
.modal{position:fixed;inset:0;background:rgba(20,20,20,.28);backdrop-filter:blur(6px);display:flex;align-items:center;justify-content:center;padding:24px;z-index:50}
.modal-card{
  background:var(--surface);border-radius:22px;padding:36px 34px;max-width:560px;width:100%;
  max-height:82vh;overflow:auto;position:relative;box-shadow:0 24px 64px rgba(0,0,0,.12);
}
.close{position:absolute;right:18px;top:18px;background:transparent;color:#b3b5ba;font-size:15px;padding:6px 10px;border-radius:8px}
.close:hover{color:var(--ink);background:var(--soft)}
.modal h2{margin:0 0 14px;font-size:21px;font-weight:600;letter-spacing:.01em}
.modal .desc{color:#4b4d52;font-size:14px;line-height:1.85;margin-bottom:24px;white-space:pre-wrap}
.links{display:flex;flex-direction:column;gap:10px}
.link{
  display:flex;justify-content:space-between;gap:14px;align-items:center;
  background:var(--soft);border-radius:12px;padding:13px 16px;font-size:13.5px;
}
.link a{color:var(--ink);text-decoration:none;font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.link a:hover{text-decoration:underline}
.link .note{color:var(--muted);font-size:12px}

/* 空状态 */
#empty{padding:80px 0}footer{padding:0 0 48px;text-align:center;color:#c0c2c7;font-size:12px;letter-spacing:.04em}

@media (max-width:640px){
  .topbar{padding:18px 20px;flex-wrap:wrap}
  .brand{order:1}
  #logout{order:2;margin-left:auto}
  .searchbox{order:3;flex-basis:100%;max-width:none;margin:6px 0 0}
  .grid{padding:24px 20px 56px;gap:14px}
  .tabs{padding:14px 20px 8px;gap:20px}
  .gate-card{padding:0 8px}
}