/* AI投递官 文档页共用样式（knowledge / guide-article / feiyong / about / changelog） */
:root{
  --ink:#0D1B2A;--brand:#4A7DF7;--brand-deep:#2F5CD9;--brand-bg:#EAF1FE;--brand-line:#C9D9FB;
  --muted:#5A6B7C;--soft:#7B8A99;--bg:#F6F8FA;--line:#E3EAF0;--warn:#B45309;--warn-bg:#FFF7ED;
  --font-sans:"Noto Sans SC","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:var(--font-sans);color:var(--ink);background:#fff;-webkit-font-smoothing:antialiased;line-height:1.8}
a{text-decoration:none;color:var(--brand)}
.wrap{max-width:880px;margin:0 auto;padding:0 24px}
header.site{position:sticky;top:0;z-index:100;background:rgba(255,255,255,.94);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);padding:14px 0}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}
.brand{font-size:18px;font-weight:800;color:var(--ink)}
.brand span{font-size:11px;color:var(--brand-deep);background:var(--brand-bg);border-radius:5px;padding:2px 7px;margin-left:6px;font-weight:600}
.nav{display:flex;gap:18px;font-size:14px;flex-wrap:wrap}
.nav a{color:var(--muted)}
.nav a:hover{color:var(--brand)}
.breadcrumb{font-size:13px;color:var(--soft);padding:26px 0 10px}
.breadcrumb a{color:var(--muted)}
h1{font-size:34px;font-weight:900;line-height:1.35;margin:0 0 10px;letter-spacing:-.3px}
.lede{font-size:16px;color:var(--muted);margin-bottom:8px}
.updated{font-size:13px;color:var(--soft);margin-bottom:32px}
h2{font-size:23px;font-weight:800;margin:52px 0 14px;line-height:1.4;letter-spacing:-.2px}
h3{font-size:17px;font-weight:700;margin:28px 0 8px}
p{font-size:15.5px;color:#243746;margin-bottom:14px}
ul,ol{margin:0 0 16px 22px}
li{font-size:15.5px;color:#243746;margin-bottom:7px}
strong{font-weight:700}
.tldr{background:var(--brand-bg);border:1px solid var(--brand-line);border-radius:12px;padding:18px 20px;margin:0 0 8px}
.tldr p{margin:0;color:#1E3A5F;font-size:15px}
.note{background:var(--warn-bg);border:1px solid #FED7AA;border-left:4px solid var(--warn);border-radius:8px;padding:14px 18px;margin:20px 0}
.note p{margin:0;color:#7C4A16;font-size:14.5px}
table{width:100%;border-collapse:collapse;margin:18px 0 24px;font-size:14.5px}
th,td{border:1px solid var(--line);padding:11px 13px;text-align:left;vertical-align:top}
th{background:var(--bg);font-weight:700;color:var(--ink);white-space:nowrap}
td{color:#2C3E4E}
tbody tr:nth-child(even) td{background:#FAFCFE}
code{background:var(--bg);border:1px solid var(--line);border-radius:4px;padding:1px 6px;font-size:13.5px;font-family:ui-monospace,Consolas,monospace;color:var(--brand-deep)}
.faq{border-top:1px solid var(--line);padding-top:8px}
.faq-item{border-bottom:1px solid var(--line);padding:22px 0}
.faq-item h3{margin:0 0 8px;font-size:17.5px}
.faq-item p{margin:0;color:var(--muted);font-size:15px}
.cta{background:linear-gradient(135deg,#0D1B2A,#1E3A5F);border-radius:14px;padding:26px 28px;margin:44px 0;color:#fff}
.cta h2{margin:0 0 8px;color:#fff;font-size:20px}
.cta p{color:#C3D0DE;font-size:14.5px;margin-bottom:16px}
.btn{display:inline-block;background:var(--brand);color:#fff;font-weight:700;font-size:14.5px;padding:11px 22px;border-radius:9px;margin-right:10px;margin-bottom:8px}
.btn.ghost{background:rgba(255,255,255,.12);color:#fff;border:1px solid rgba(255,255,255,.28)}
.btn.dark{background:var(--brand-deep);color:#fff}
.rel{background:var(--bg);border:1px solid var(--line);border-radius:12px;padding:20px 22px;margin:40px 0}
.rel h2{margin:0 0 12px;font-size:17px}
.rel ul{margin-bottom:0}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:16px;margin:22px 0 8px}
.card{border:1px solid var(--line);border-radius:12px;padding:18px 20px;background:#fff;transition:border-color .18s,transform .18s}
.card:hover{border-color:var(--brand-line);transform:translateY(-2px)}
.card h3{margin:0 0 6px;font-size:16.5px}
.card h3 a{color:var(--ink)}
.card h3 a:hover{color:var(--brand)}
.card .tag{font-size:11.5px;color:var(--brand-deep);background:var(--brand-bg);border-radius:4px;padding:2px 6px;margin-left:6px;font-weight:600;vertical-align:1px}
.card p{margin:0;font-size:14px;color:var(--muted);line-height:1.7}
.timeline{list-style:none;margin-left:0}
.timeline li{border-left:2px solid var(--brand-line);padding:0 0 22px 18px;margin:0;position:relative}
.timeline li::before{content:"";position:absolute;left:-6px;top:7px;width:9px;height:9px;border-radius:50%;background:var(--brand)}
.timeline .when{font-size:13px;color:var(--soft);font-weight:600}
.timeline .what{font-size:15px;color:#243746}
footer.site{background:var(--ink);color:#8FA3B5;padding:44px 0;margin-top:72px;font-size:13px}
footer.site .cols{display:grid;grid-template-columns:repeat(auto-fit,minmax(190px,1fr));gap:26px;margin-bottom:26px}
footer.site h4{color:#fff;font-size:14px;margin-bottom:10px;font-weight:700}
footer.site a{color:#C3D0DE;display:block;margin-bottom:7px;font-size:13px}
footer.site .copy{border-top:1px solid #22384C;padding-top:18px;line-height:1.9;font-size:12.5px}
@media (max-width:640px){h1{font-size:26px}h2{font-size:20px}.nav{gap:12px;font-size:13px}table{font-size:13px;table-layout:fixed;word-break:break-word}th,td{padding:8px 9px}}