:root{--brand:#e8590c;--brand-dark:#c2410c;--brand-light:#fff4ed;--brand-2:#f59e0b;--brand-3:#fb923c;--ink:#1f2328;--ink-2:#4a5058;--ink-3:#6b7280;--line:#e5e7eb;--bg:#ffffff;--bg-soft:#faf7f4;--glass:rgba(255,255,255,.72);--glass-line:rgba(255,255,255,.6);--radius:14px;--radius-lg:22px;--shadow:0 6px 24px rgba(31,35,40,.08);--shadow-lg:0 18px 48px rgba(232,89,12,.14);--maxw:1180px;--ease:cubic-bezier(.22,.61,.36,1)}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Segoe UI",Roboto,Helvetica,Arial,sans-serif;color:var(--ink);background:var(--bg);line-height:1.75;font-size:16px;transition:background .35s ease,color .35s ease;overflow-x:hidden}
img,svg{max-width:100%;display:block}
a{color:var(--brand-dark);text-decoration:none;transition:color .2s ease}
a:hover{text-decoration:underline}
ul,ol{padding-left:1.4em}
h1,h2,h3,h4{line-height:1.35;color:var(--ink);font-weight:700;letter-spacing:-.01em}
h1{font-size:clamp(1.6rem,3.4vw,2.4rem)}
h2{font-size:clamp(1.3rem,2.4vw,1.75rem);margin-bottom:.6em}
h3{font-size:clamp(1.08rem,1.8vw,1.28rem);margin:1.2em 0 .5em}
h4{font-size:1.02rem;margin:1em 0 .4em;color:var(--ink-2)}
p{margin:.6em 0;color:var(--ink-2)}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}
section{padding:56px 0;border-bottom:1px solid var(--line);position:relative}
section:last-of-type{border-bottom:none}
.eyebrow{display:inline-block;font-size:.8rem;letter-spacing:.12em;color:var(--brand-dark);background:linear-gradient(120deg,var(--brand-light),rgba(245,158,11,.16));padding:4px 12px;border-radius:999px;font-weight:600;margin-bottom:14px;border:1px solid rgba(232,89,12,.14)}
.lead{font-size:1.05rem;color:var(--ink-2)}
.skip{position:absolute;left:-9999px}
.skip:focus{left:12px;top:12px;background:#fff;padding:8px 14px;border:2px solid var(--brand);border-radius:8px;z-index:9999}
/* header */
header.site{position:sticky;top:0;z-index:1000;background:var(--glass);backdrop-filter:saturate(180%) blur(14px);-webkit-backdrop-filter:saturate(180%) blur(14px);border-bottom:1px solid var(--line);transition:background .35s ease,border-color .35s ease}
.nav{display:flex;align-items:center;gap:18px;height:64px}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:1.12rem;color:var(--ink)}
.brand .logo{width:36px;height:36px;flex:0 0 36px;transition:transform .4s var(--ease)}
.brand:hover .logo{transform:rotate(-8deg) scale(1.06)}
.brand:hover{text-decoration:none}
.nav-links{display:flex;gap:6px;margin-left:auto;flex-wrap:wrap}
.nav-links a{color:var(--ink-2);font-size:.92rem;padding:8px 10px;border-radius:8px;position:relative;transition:background .2s ease,color .2s ease,transform .2s ease}
.nav-links a:hover{background:var(--brand-light);color:var(--brand-dark);text-decoration:none;transform:translateY(-1px)}
.nav-tools{display:flex;align-items:center;gap:8px}
.search-box{display:flex;align-items:center;border:1px solid var(--line);border-radius:999px;padding:4px 6px 4px 12px;background:var(--glass);backdrop-filter:blur(8px);transition:border-color .25s ease,box-shadow .25s ease}
.search-box:focus-within{border-color:var(--brand);box-shadow:0 0 0 4px rgba(232,89,12,.12)}
.search-box input{border:none;outline:none;font-size:.88rem;width:130px;background:transparent;color:var(--ink)}
.search-box button{border:none;background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;border-radius:999px;padding:5px 12px;font-size:.82rem;cursor:pointer;transition:transform .2s ease,filter .2s ease}
.search-box button:hover{transform:translateY(-1px);filter:brightness(1.06)}
.icon-btn{border:1px solid var(--line);background:var(--glass);border-radius:999px;width:38px;height:38px;display:grid;place-items:center;cursor:pointer;color:var(--ink-2);transition:transform .25s var(--ease),background .25s ease,color .25s ease}
.icon-btn:hover{transform:rotate(18deg);color:var(--brand-dark);background:var(--brand-light)}
.menu-btn{display:none}
/* hero */
.hero{background:linear-gradient(160deg,var(--brand-light),#fff 55%,rgba(245,158,11,.08));padding:64px 0 48px;border-bottom:1px solid var(--line);overflow:hidden}
.hero::before{content:"";position:absolute;width:520px;height:520px;right:-140px;top:-180px;background:radial-gradient(circle,rgba(232,89,12,.22),transparent 68%);filter:blur(20px);pointer-events:none;animation:floatBlob 12s ease-in-out infinite}
.hero::after{content:"";position:absolute;width:380px;height:380px;left:-120px;bottom:-180px;background:radial-gradient(circle,rgba(245,158,11,.2),transparent 70%);filter:blur(18px);pointer-events:none;animation:floatBlob 15s ease-in-out infinite reverse}
@keyframes floatBlob{0%,100%{transform:translate3d(0,0,0) scale(1)}50%{transform:translate3d(-24px,28px,0) scale(1.08)}}
.hero-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:40px;align-items:center;position:relative;z-index:1}
.hero h1{margin-bottom:16px;background:linear-gradient(120deg,var(--ink) 30%,var(--brand-dark) 100%);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.hero .lead{max-width:34em}
.hero-cta{display:flex;gap:12px;flex-wrap:wrap;margin-top:22px}
.btn{display:inline-flex;align-items:center;gap:8px;padding:12px 22px;border-radius:999px;font-weight:600;font-size:.95rem;border:1px solid transparent;cursor:pointer;transition:transform .25s var(--ease),box-shadow .25s ease,background .25s ease,filter .25s ease}
.btn:hover{transform:translateY(-2px)}
.btn-primary{background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;box-shadow:0 8px 22px rgba(232,89,12,.28)}
.btn-primary:hover{filter:brightness(1.06);box-shadow:0 12px 30px rgba(232,89,12,.36);text-decoration:none}
.btn-ghost{background:var(--glass);color:var(--brand-dark);border-color:var(--brand);backdrop-filter:blur(8px)}
.btn-ghost:hover{background:var(--brand-light);text-decoration:none;box-shadow:0 8px 20px rgba(232,89,12,.16)}
.hero-figure{background:var(--glass);border:1px solid var(--glass-line);border-radius:var(--radius-lg);padding:18px;box-shadow:var(--shadow-lg);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);transition:transform .4s var(--ease),box-shadow .4s ease}
.hero-figure:hover{transform:translateY(-4px) rotate(-.4deg)}
.hero-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin-top:26px}
.stat{background:var(--glass);border:1px solid var(--line);border-radius:var(--radius);padding:14px 16px;backdrop-filter:blur(10px);transition:transform .3s var(--ease),box-shadow .3s ease,border-color .3s ease}
.stat:hover{transform:translateY(-4px);box-shadow:var(--shadow);border-color:rgba(232,89,12,.3)}
.stat b{display:block;font-size:1.5rem;color:var(--brand-dark);font-variant-numeric:tabular-nums}
.stat span{font-size:.82rem;color:var(--ink-3)}
/* banner carousel */
.carousel{position:relative;overflow:hidden;border-radius:var(--radius-lg);border:1px solid var(--line);background:var(--glass);box-shadow:var(--shadow);backdrop-filter:blur(12px)}
.slides{display:flex;transition:transform .55s var(--ease)}
.slide{min-width:100%;padding:26px}
.slide h3{margin-top:0;color:var(--brand-dark)}
.slide p{margin:6px 0 0}
.dots{display:flex;gap:8px;justify-content:center;padding:12px}
.dots button{width:9px;height:9px;border-radius:50%;border:none;background:#e3d5cb;cursor:pointer;padding:0;transition:background .3s ease,width .3s ease}
.dots button:hover{background:var(--brand-3)}
.dots button.active{background:linear-gradient(90deg,var(--brand),var(--brand-2));width:22px;border-radius:999px}
/* cards */
.grid{display:grid;gap:20px}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-2{grid-template-columns:repeat(2,1fr)}
.card{background:var(--glass);border:1px solid var(--line);border-radius:var(--radius);padding:22px;box-shadow:0 2px 10px rgba(31,35,40,.04);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);transition:transform .3s var(--ease),box-shadow .3s ease,border-color .3s ease,background .3s ease;position:relative;overflow:hidden}
.card::before{content:"";position:absolute;inset:0;background:linear-gradient(135deg,rgba(232,89,12,.06),transparent 42%);opacity:0;transition:opacity .3s ease;pointer-events:none}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow);border-color:rgba(232,89,12,.28)}
.card:hover::before{opacity:1}
.card h3{margin-top:0}
.card .meta{font-size:.8rem;color:var(--ink-3);margin-bottom:8px;display:flex;gap:10px;flex-wrap:wrap;align-items:center}
.tag{display:inline-block;font-size:.74rem;background:linear-gradient(120deg,var(--brand-light),rgba(245,158,11,.14));color:var(--brand-dark);padding:2px 9px;border-radius:999px;font-weight:600;border:1px solid rgba(232,89,12,.12)}
.card a[aria-label^="阅读全文"]{display:inline-block;margin-top:8px;font-weight:600;transition:transform .25s var(--ease)}
.card a[aria-label^="阅读全文"]:hover{transform:translateX(4px);text-decoration:none}
blockquote.card{border-left:4px solid var(--brand)}
/* table */
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);background:var(--glass);backdrop-filter:blur(8px)}
table{border-collapse:collapse;width:100%;font-size:.92rem;min-width:560px}
th,td{padding:12px 14px;text-align:left;border-bottom:1px solid var(--line)}
th{background:linear-gradient(120deg,var(--bg-soft),rgba(245,158,11,.08));color:var(--ink);font-weight:700}
tr:last-child td{border-bottom:none}
tbody tr{transition:background .2s ease}
tbody tr:hover{background:rgba(232,89,12,.05)}
/* faq */
.faq-item{border:1px solid var(--line);border-radius:12px;margin-bottom:12px;background:var(--glass);overflow:hidden;backdrop-filter:blur(8px);transition:border-color .3s ease,box-shadow .3s ease}
.faq-item:hover{border-color:rgba(232,89,12,.3)}
.faq-item.open{box-shadow:var(--shadow);border-color:rgba(232,89,12,.35)}
.faq-q{width:100%;text-align:left;background:none;border:none;padding:16px 18px;font-size:1rem;font-weight:600;color:var(--ink);cursor:pointer;display:flex;justify-content:space-between;gap:12px;align-items:center;transition:color .2s ease}
.faq-q:hover{color:var(--brand-dark)}
.faq-q .plus{color:var(--brand);font-size:1.2rem;transition:transform .3s var(--ease)}
.faq-item.open .plus{transform:rotate(45deg)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .4s var(--ease);padding:0 18px}
.faq-item.open .faq-a{max-height:600px;padding-bottom:16px}
.faq-a p{margin:.4em 0;font-size:.94rem}
/* steps */
.steps{counter-reset:step;display:grid;gap:16px}
.step{position:relative;padding:18px 18px 18px 64px;background:var(--glass);border:1px solid var(--line);border-radius:var(--radius);backdrop-filter:blur(8px);transition:transform .3s var(--ease),box-shadow .3s ease,border-color .3s ease}
.step:hover{transform:translateX(4px);box-shadow:var(--shadow);border-color:rgba(232,89,12,.3)}
.step::before{counter-increment:step;content:counter(step);position:absolute;left:16px;top:16px;width:34px;height:34px;border-radius:50%;background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;display:grid;place-items:center;font-weight:700;box-shadow:0 4px 12px rgba(232,89,12,.3)}
.step h4{margin:0 0 4px}
/* toc */
.toc{background:linear-gradient(140deg,var(--bg-soft),rgba(245,158,11,.06));border:1px solid var(--line);border-radius:var(--radius);padding:20px;backdrop-filter:blur(8px)}
.toc ol{columns:2;column-gap:28px;margin:0}
.toc li{break-inside:avoid;margin-bottom:6px;font-size:.92rem}
.toc a{transition:color .2s ease,padding-left .2s ease}
.toc a:hover{padding-left:4px}
/* breadcrumb */
.breadcrumb{font-size:.85rem;color:var(--ink-3);padding:14px 0 0}
.breadcrumb a{color:var(--ink-3)}
.breadcrumb a:hover{color:var(--brand-dark)}
.breadcrumb span{margin:0 6px}
/* footer */
footer.site{background:linear-gradient(160deg,#1f2328,#171a1f 70%);color:#c9ced6;padding:52px 0 26px;font-size:.9rem}
footer.site a{color:#e7eaee;transition:color .2s ease}
footer.site a:hover{color:var(--brand-3);text-decoration:none}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1.2fr;gap:28px}
footer.site h4{color:#fff;font-size:.95rem;margin-bottom:12px}
footer.site ul{list-style:none;padding:0}
footer.site li{margin-bottom:8px}
.footer-bottom{border-top:1px solid #33383f;margin-top:32px;padding-top:18px;display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;font-size:.82rem;color:#9aa1ab}
/* back to top */
#toTop{position:fixed;right:20px;bottom:24px;width:46px;height:46px;border-radius:50%;border:none;background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;font-size:1.1rem;cursor:pointer;box-shadow:0 10px 26px rgba(232,89,12,.36);opacity:0;pointer-events:none;transition:opacity .3s ease,transform .3s var(--ease);z-index:900}
#toTop.show{opacity:1;pointer-events:auto}
#toTop:hover{transform:translateY(-4px) scale(1.06)}
/* dark mode */
body.dark{--ink:#e8eaed;--ink-2:#c3c8cf;--ink-3:#9aa1ab;--line:#33383f;--bg:#16181c;--bg-soft:#1d2025;--brand-light:#2a1a10;--glass:rgba(29,32,37,.72);--glass-line:rgba(255,255,255,.06);--shadow:0 8px 28px rgba(0,0,0,.42);--shadow-lg:0 18px 48px rgba(0,0,0,.5)}
body.dark header.site{background:rgba(22,24,28,.86)}
body.dark .card,body.dark .stat,body.dark .hero-figure,body.dark .carousel,body.dark .faq-item,body.dark .step,body.dark .search-box,body.dark .icon-btn,body.dark .table-wrap,body.dark .toc{background:var(--glass)}
body.dark .btn-ghost{background:rgba(29,32,37,.8)}
body.dark .hero{background:linear-gradient(160deg,#2a1a10,#16181c 58%,rgba(245,158,11,.06))}
body.dark .hero h1{background:linear-gradient(120deg,#fff 30%,var(--brand-3) 100%);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
body.dark th{background:linear-gradient(120deg,#22262c,rgba(232,89,12,.12))}
body.dark .slide h3{color:var(--brand-3)}
body.dark .eyebrow{color:var(--brand-3);border-color:rgba(232,89,12,.3)}
body.dark .dots button{background:#3a3f47}
body.dark .dots button.active{background:linear-gradient(90deg,var(--brand),var(--brand-2))}
body.dark .nav-links a:hover{background:rgba(232,89,12,.16);color:var(--brand-3)}
/* reveal */
.reveal{opacity:0;transform:translateY(20px);transition:opacity .65s var(--ease),transform .65s var(--ease)}
.reveal.in{opacity:1;transform:none}
.reveal:nth-child(2){transition-delay:.06s}
.reveal:nth-child(3){transition-delay:.12s}
.reveal:nth-child(4){transition-delay:.18s}
.reveal:nth-child(5){transition-delay:.24s}
.reveal:nth-child(6){transition-delay:.3s}
@media (prefers-reduced-motion:reduce){
.reveal{opacity:1;transform:none;transition:none}
.slides{transition:none}
.hero::before,.hero::after{animation:none}
*{animation-duration:.001ms!important;transition-duration:.001ms!important}
}
/* responsive */
@media (max-width:960px){
.hero-grid{grid-template-columns:1fr}
.grid-3{grid-template-columns:repeat(2,1fr)}
.footer-grid{grid-template-columns:1fr 1fr}
.hero::before{width:380px;height:380px;right:-160px}
}
@media (max-width:720px){
.nav-links{display:none;position:absolute;left:0;right:0;top:64px;background:var(--glass);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);flex-direction:column;padding:12px 16px;border-bottom:1px solid var(--line);box-shadow:var(--shadow)}
.nav-links.open{display:flex;animation:navDrop .3s var(--ease)}
@keyframes navDrop{from{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:none}}
.menu-btn{display:grid}
.search-box input{width:90px}
.grid-3,.grid-2{grid-template-columns:1fr}
.footer-grid{grid-template-columns:1fr}
.toc ol{columns:1}
.hero-stats{grid-template-columns:1fr}
section{padding:40px 0}
.hero{padding:44px 0 36px}
.hero::before,.hero::after{opacity:.6}
}
@media (max-width:420px){
.search-box{display:none}
.nav{gap:10px}
.brand span{font-size:1rem}
}