/* 共享样式：宣传页 + 选配页。颜色全部走 token，暗色模式在下方重定义 */
:root{
  --bg:#f5f7f9; --panel:#ffffff; --panel-2:#eef2f5; --fg:#14202b; --muted:#5b6876; --line:#dde3e8;
  --accent:#1f6fb2; --accent-2:#0f8f86; --accent-fg:#ffffff; --signal:#e8902a; --danger:#d9483b;
  --ink:#0d1822; --ink-2:#14222f; --ink-fg:#e8eef3; --ink-muted:#93a3b2; --ink-line:#24364a;
  --stage:#e6ebef;
  --radius:10px;
  --f-sans:"Microsoft YaHei","PingFang SC","Noto Sans SC","Hiragino Sans GB",system-ui,sans-serif;
  --f-mono:"JetBrains Mono","Cascadia Mono",Consolas,ui-monospace,monospace;
  color-scheme:light;
}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){
  --bg:#0f1419; --panel:#161d24; --panel-2:#1b242c; --fg:#e4eaef; --muted:#93a1ae; --line:#26313b;
  --accent:#5aa5e6; --accent-2:#3cc2b6; --accent-fg:#0b1722; --signal:#f0a54a; --danger:#ef6b5e;
  --ink:#0a1016; --ink-2:#111a22; --stage:#141b21; color-scheme:dark}}
:root[data-theme="dark"]{
  --bg:#0f1419; --panel:#161d24; --panel-2:#1b242c; --fg:#e4eaef; --muted:#93a1ae; --line:#26313b;
  --accent:#5aa5e6; --accent-2:#3cc2b6; --accent-fg:#0b1722; --signal:#f0a54a; --danger:#ef6b5e;
  --ink:#0a1016; --ink-2:#111a22; --stage:#141b21; color-scheme:dark}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--fg);font-family:var(--f-sans);line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:inherit}
img,canvas,svg{display:block;max-width:100%}
.wrap{max-width:1200px;margin:0 auto;padding:0 24px}
.mono{font-family:var(--f-mono);font-variant-numeric:tabular-nums}

/* ---------- 顶部导航 ---------- */
.nav{position:sticky;top:0;z-index:20;background:color-mix(in srgb,var(--ink) 88%,transparent);backdrop-filter:blur(10px);border-bottom:1px solid var(--ink-line);color:var(--ink-fg)}
.nav .wrap{display:flex;align-items:center;gap:28px;height:60px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;letter-spacing:.02em;text-decoration:none;white-space:nowrap}
.brand-mark{width:26px;height:26px;border-radius:6px;background:linear-gradient(135deg,var(--accent),var(--accent-2));position:relative;overflow:hidden}
.brand-mark::after{content:"";position:absolute;left:0;right:0;top:55%;height:2px;background:var(--signal);box-shadow:0 0 8px var(--signal)}
.brand small{font-weight:400;color:var(--ink-muted);font-size:12px;margin-left:2px}
.nav-links{display:flex;gap:22px;font-size:14px;color:var(--ink-muted);flex:1}
.nav-links a{text-decoration:none}
.nav-links a:hover,.nav-links a[aria-current]{color:var(--ink-fg)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;border-radius:8px;padding:10px 18px;font:inherit;font-size:14px;font-weight:600;text-decoration:none;cursor:pointer;border:1px solid transparent;white-space:nowrap}
.btn-primary{background:var(--accent);color:var(--accent-fg)}
.btn-primary:hover{filter:brightness(1.08)}
.btn-ghost{border-color:currentColor;color:inherit;background:transparent;opacity:.9}
.btn-ghost:hover{opacity:1}
.btn:focus-visible,a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.theme-toggle{background:none;border:1px solid var(--ink-line);color:var(--ink-muted);border-radius:8px;width:34px;height:34px;cursor:pointer;font-size:15px}

/* ---------- 通用区块 ---------- */
section{padding:88px 0}
.eyebrow{font-size:12px;letter-spacing:.14em;color:var(--accent);font-weight:700;margin:0 0 10px}
h2.title{font-size:clamp(26px,3.2vw,36px);line-height:1.25;margin:0 0 14px;text-wrap:balance}
.lead{color:var(--muted);font-size:16px;max-width:680px;margin:0}
.sec-head{margin-bottom:44px}
.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius)}
.tag{display:inline-block;font-size:12px;padding:2px 8px;border-radius:999px;background:var(--panel-2);color:var(--muted);border:1px solid var(--line)}
.placeholder-note{font-size:12px;color:var(--muted);border-left:3px solid var(--signal);padding:2px 0 2px 10px;margin-top:18px}

footer{background:var(--ink);color:var(--ink-muted);font-size:13px;padding:40px 0}
footer .wrap{display:flex;flex-wrap:wrap;gap:16px 40px;justify-content:space-between}

@media (max-width:760px){
  .wrap{padding:0 16px}
  .nav-links{display:none}
  section{padding:60px 0}
}