:root{
  --ink:#0e1726;--sub:#54606f;--muted:#8a94a3;
  --line:#e8ecf2;--bg:#ffffff;--soft:#f7f9fc;--soft2:#f1f5fa;
  --brand:#1554d8;--brand-2:#0ea5e9;--brand-3:#6d5ef0;
  --grad:linear-gradient(120deg,#1554d8 0%,#0ea5e9 48%,#6d5ef0 100%);
  --navy:#08131f;
  --sh-1:0 1px 2px rgba(13,24,40,.05);
  --sh-2:0 4px 14px rgba(13,24,40,.06);
  --sh-3:0 14px 40px rgba(13,24,40,.10);
  --r:14px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--bg);line-height:1.85;font-size:16.5px;-webkit-font-smoothing:antialiased}
a{color:var(--brand);text-decoration:none;transition:color .18s ease}
a:hover{color:var(--brand-2);text-decoration:none}

/* ---------- 导航：毛玻璃 + 渐变下划线 ---------- */
header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.82);backdrop-filter:saturate(180%) blur(14px);-webkit-backdrop-filter:saturate(180%) blur(14px);border-bottom:1px solid rgba(232,236,242,.95)}
.nav{max-width:1080px;margin:0 auto;padding:0 24px;height:64px;display:flex;align-items:center;gap:26px;overflow-x:auto;scrollbar-width:none}
.nav::-webkit-scrollbar{display:none}
.brand{display:inline-flex;align-items:center;gap:9px;font-weight:800;color:var(--ink);font-size:16.5px;letter-spacing:-.2px;white-space:nowrap}
.brand::before{content:"";width:22px;height:22px;border-radius:7px;background:var(--grad);box-shadow:0 2px 10px rgba(21,84,216,.4)}
.nav a{font-size:14.5px;color:var(--sub);white-space:nowrap;position:relative;padding:5px 0}
.nav a::after{content:"";position:absolute;left:0;right:100%;bottom:0;height:2px;background:var(--grad);border-radius:2px;transition:right .25s ease}
.nav a:hover{color:var(--brand)}
.nav a:hover::after{right:0}

/* ---------- 首屏 Hero：深色渐变 + 光晕 + 网格 ---------- */
.hero{position:relative;background:linear-gradient(160deg,#08131f 0%,#0d2033 45%,#12283f 100%);color:#fff;overflow:hidden}
.hero::before{content:"";position:absolute;inset:0;background:
  radial-gradient(900px 380px at 12% -10%,rgba(14,165,233,.35),transparent 60%),
  radial-gradient(700px 330px at 88% 8%,rgba(109,94,240,.30),transparent 62%)}
.hero::after{content:"";position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.05) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.05) 1px,transparent 1px);background-size:46px 46px;-webkit-mask-image:radial-gradient(70% 60% at 50% 0%,#000 40%,transparent 100%);mask-image:radial-gradient(70% 60% at 50% 0%,#000 40%,transparent 100%)}
.hero>.wrap{position:relative;z-index:2;max-width:1080px;padding:62px 24px 54px}
.hero h1{color:#fff;font-size:38px;line-height:1.32;margin:0 0 14px;font-weight:800;letter-spacing:-.6px}
.hero .meta{color:#a9c7e8;font-size:15.5px;margin:0}
.hero .meta a{color:#8fd6f7}
.eyebrow{display:inline-block;font-size:12.5px;letter-spacing:.13em;text-transform:uppercase;color:#7fd3f5;border:1px solid rgba(127,211,245,.35);background:rgba(14,165,233,.12);padding:4px 12px;border-radius:99px;margin-bottom:16px}

/* ---------- 正文 ---------- */
main{padding:0 0 72px}
.wrap{max-width:880px;margin:0 auto;padding:0 24px}
.content{padding-top:40px}
h1{font-size:31px;line-height:1.4;margin:0 0 14px;font-weight:800;letter-spacing:-.4px}
h2{font-size:22px;margin:44px 0 14px;padding-left:12px;border-left:4px solid var(--brand);border-image:var(--grad) 1;font-weight:750;letter-spacing:-.2px}
h3{font-size:17.5px;margin:28px 0 8px;font-weight:700}
p{margin:0 0 15px}
ul,ol{margin:0 0 15px;padding-left:22px}
li{margin:6px 0}
.meta{color:var(--sub);font-size:13.5px;margin:0 0 24px}
.answer{background:linear-gradient(180deg,#f3f8ff,#eef5ff);border:1px solid #d8e7ff;border-left:4px solid var(--brand);border-radius:14px;padding:18px 20px;margin:0 0 24px;box-shadow:var(--sh-1)}
.answer p:last-child{margin-bottom:0}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:14px;margin:16px 0 10px}
.card{border:1px solid var(--line);border-radius:var(--r);padding:16px 18px;background:#fff;box-shadow:var(--sh-1);transition:transform .22s ease,box-shadow .22s ease,border-color .22s ease}
.card:hover{transform:translateY(-3px);box-shadow:var(--sh-3);border-color:#c9dcfb}
.card b{display:block;margin-bottom:5px;font-size:15.5px}
.card span{color:var(--sub);font-size:14px;display:block;line-height:1.7}
table{border-collapse:separate;border-spacing:0;width:100%;margin:14px 0 20px;font-size:14.5px;border:1px solid var(--line);border-radius:12px;overflow:hidden;box-shadow:var(--sh-1)}
th,td{padding:11px 13px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}
th{background:var(--soft2);font-weight:700;color:#243044;font-size:14px}
tr:last-child td{border-bottom:0}
tbody tr:nth-child(even){background:#fcfdfe}
tbody tr:hover{background:#f4f8ff}
.faq details{border:1px solid var(--line);border-radius:12px;padding:12px 16px;margin-bottom:10px;background:#fff;box-shadow:var(--sh-1);transition:border-color .2s,box-shadow .2s}
.faq details[open]{border-color:#c9dcfb;box-shadow:var(--sh-2)}
.faq summary{cursor:pointer;font-weight:650;font-size:15.5px;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq summary::before{content:"＋";color:var(--brand);font-weight:700;display:inline-block;width:18px}
.faq details[open] summary::before{content:"－"}
.faq p{margin:10px 0 0;color:var(--sub);font-size:14.5px}
.tag{display:inline-block;background:var(--soft);border:1px solid var(--line);border-radius:8px;padding:3px 10px;font-size:13px;color:var(--sub);margin:0 6px 6px 0}
.note{background:linear-gradient(180deg,#fffaf0,#fff6e3);border:1px solid #f3e0b0;border-radius:12px;padding:14px 17px;font-size:14.5px;margin:16px 0;box-shadow:var(--sh-1)}

/* ---------- 页脚 ---------- */
footer{border-top:1px solid var(--line);padding:34px 0 44px;color:var(--sub);font-size:13.5px;background:var(--soft)}
footer .wrap{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;max-width:1080px}
footer b{color:var(--ink)}

/* ---------- 入场动效 ---------- */
@keyframes up{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}
.hero>.wrap>*{animation:up .55s cubic-bezier(.2,.7,.3,1) both}
.hero>.wrap>*:nth-child(2){animation-delay:.06s}
.hero>.wrap>*:nth-child(3){animation-delay:.12s}

@media(max-width:720px){
  .hero>.wrap{padding:44px 20px 38px}
  .hero h1{font-size:26px}
  h1{font-size:24px}
  h2{font-size:19px}
  .nav{gap:17px;height:58px;padding:0 18px}
  .wrap{padding:0 18px}
}