:root{--bg:#0b0d12;--bg-soft:#111421;--bg-card:#161a28;--bg-card-hi:#1c2135;--line:#242838;--line-hi:#363c54;--text:#eef0f8;--muted:#9aa0b5;--primary:#7c6cff;--primary-hi:#9a8bff;--accent:#67e8f9;--accent-dim:#4bc9db;--radius:10px;--radius-lg:16px;--max:1200px;font-family:"PingFang SC","Hiragino Sans GB","Microsoft YaHei",Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",sans-serif;color:var(--text);background:var(--bg)}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{background:radial-gradient(1200px 600px at 80% -10%,rgba(124,108,255,.22),transparent 60%),radial-gradient(900px 500px at 10% 10%,rgba(103,232,249,.08),transparent 55%),var(--bg);line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{max-width:var(--max);margin:0 auto;padding-inline:28px}

/* ===== Header ===== */
.site-header{position:sticky;top:0;z-index:50;backdrop-filter:saturate(140%) blur(18px);-webkit-backdrop-filter:saturate(140%) blur(18px);background:rgba(11,13,18,.72);border-bottom:1px solid var(--line)}
.header-inner{height:68px;display:flex;align-items:center;gap:36px}
.logo{font-weight:900;letter-spacing:.06em;font-size:20px;color:var(--text);white-space:nowrap}
.logo span{color:var(--accent)}
.logo small{color:var(--muted);font-size:11px;margin-left:5px;letter-spacing:.1em}
.site-nav{display:flex;gap:28px;flex:1;font-size:14px;color:var(--muted)}
.site-nav a{position:relative;padding:4px 0;transition:color .15s}
.site-nav a:hover{color:var(--text)}

/* ===== Buttons ===== */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:10px 18px;font-weight:700;font-size:14px;border-radius:var(--radius);border:1px solid transparent;cursor:pointer;transition:transform .15s,box-shadow .15s,background .15s,border-color .15s;line-height:1;white-space:nowrap}
.btn-primary{background:linear-gradient(135deg,var(--primary),#a07bff);color:#0b0d12;box-shadow:0 6px 24px rgba(124,108,255,.35)}
.btn-primary:hover{transform:translateY(-1px);box-shadow:0 10px 28px rgba(124,108,255,.45)}
.btn-outline{background:transparent;color:var(--text);border-color:var(--line-hi)}
.btn-outline:hover{border-color:var(--accent);color:var(--accent)}
.btn-large{padding:14px 26px;font-size:15px}

/* ===== Hero ===== */
.hero{padding:88px 0 72px;position:relative;overflow:hidden}
.hero::before{content:"";position:absolute;inset:auto 0 -200px 0;height:400px;background:radial-gradient(600px 300px at 50% 100%,rgba(124,108,255,.18),transparent 60%);pointer-events:none}
.hero-inner{position:relative;max-width:960px;margin:0 auto;text-align:center}
.eyebrow,.section-eyebrow{display:inline-block;font-size:12px;letter-spacing:.22em;color:var(--accent);font-weight:800;text-transform:uppercase;margin-bottom:22px;padding:6px 14px;border:1px solid rgba(103,232,249,.3);border-radius:999px;background:rgba(103,232,249,.05)}
.hero h1{font-size:clamp(40px,6.2vw,68px);line-height:1.15;letter-spacing:-.02em;font-weight:800;margin:0 0 24px}
.hero h1 em{color:var(--primary-hi);font-style:normal;background:linear-gradient(135deg,#9a8bff,#67e8f9);-webkit-background-clip:text;background-clip:text;color:transparent}
.lead{font-size:17px;line-height:1.9;color:var(--muted);max-width:720px;margin:0 auto 36px}
.hero-cta{display:flex;gap:16px;justify-content:center;flex-wrap:wrap;margin-bottom:60px}
.hero-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line);border-radius:var(--radius-lg);overflow:hidden;max-width:860px;margin:0 auto}
.stat-item{background:var(--bg-soft);padding:28px 24px;text-align:center}
.stat-number{font-size:38px;font-weight:800;line-height:1;background:linear-gradient(135deg,#9a8bff,#67e8f9);-webkit-background-clip:text;background-clip:text;color:transparent;margin-bottom:10px}
.stat-label{font-size:13px;color:var(--muted);line-height:1.5}

/* ===== Section ===== */
.section{padding:96px 0;position:relative}
.section.bg-light{background:linear-gradient(180deg,transparent,rgba(22,26,40,.5),transparent)}
.section-header{text-align:center;max-width:780px;margin:0 auto 58px}
.section-title{font-size:clamp(30px,4vw,42px);line-height:1.25;letter-spacing:-.02em;font-weight:800;margin:0 0 18px}
.section-subtitle{color:var(--muted);font-size:16px;line-height:1.9;margin:0}

/* ===== Feature grid (topics) ===== */
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.feature-card{display:block;background:var(--bg-card);border:1px solid var(--line);border-radius:var(--radius-lg);padding:32px 28px;position:relative;transition:transform .18s,border-color .18s,background .18s;overflow:hidden}
.feature-card::before{content:"";position:absolute;inset:0;background:linear-gradient(135deg,rgba(124,108,255,.08),transparent 50%);opacity:0;transition:opacity .2s}
.feature-card:hover{transform:translateY(-4px);border-color:var(--primary);background:var(--bg-card-hi)}
.feature-card:hover::before{opacity:1}
.feature-card>*{position:relative}
.feature-index{position:absolute;top:24px;right:28px;font-size:12px;color:var(--muted);font-weight:700;letter-spacing:.1em}
.feature-tag{display:inline-block;font-size:11px;font-weight:800;letter-spacing:.14em;text-transform:uppercase;color:var(--primary-hi);padding:5px 10px;background:rgba(124,108,255,.14);border-radius:999px;margin-bottom:22px}
.feature-title{font-size:20px;line-height:1.35;margin:0 0 12px;font-weight:800;letter-spacing:-.01em}
.feature-desc{color:var(--muted);font-size:14px;line-height:1.75;margin:0 0 18px}
.feature-link{color:var(--accent);font-size:13px;font-weight:800;letter-spacing:.02em}

/* ===== Steps ===== */
.step-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-bottom:48px}
.step-item{background:var(--bg-card);border:1px solid var(--line);border-radius:var(--radius-lg);padding:36px 30px;position:relative}
.step-number{font-size:52px;font-weight:900;line-height:1;background:linear-gradient(135deg,#9a8bff,#67e8f9);-webkit-background-clip:text;background-clip:text;color:transparent;margin-bottom:20px;letter-spacing:-.04em}
.step-title{font-size:20px;margin:0 0 12px;font-weight:800}
.step-desc{color:var(--muted);font-size:14.5px;line-height:1.85;margin:0}
.cta-container{text-align:center;margin-top:12px}

/* ===== Advantages ===== */
.advantage-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line);border-radius:var(--radius-lg);overflow:hidden}
.advantage-item{background:var(--bg-soft);padding:36px 32px;transition:background .18s}
.advantage-item:hover{background:var(--bg-card-hi)}
.advantage-title{font-size:13px;color:var(--accent);font-weight:800;letter-spacing:.18em;margin-bottom:16px}
.advantage-subtitle{font-size:19px;margin:0 0 14px;font-weight:800}
.advantage-desc{color:var(--muted);font-size:14px;line-height:1.8;margin:0}

/* ===== Models ===== */
.model-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;margin-bottom:40px}
.model-card{background:var(--bg-card);border:1px solid var(--line);border-radius:var(--radius-lg);padding:34px 30px;position:relative;transition:transform .18s,border-color .18s}
.model-card:hover{transform:translateY(-3px);border-color:var(--line-hi)}
.model-card.featured{border-color:var(--primary);background:linear-gradient(165deg,rgba(124,108,255,.1),var(--bg-card));box-shadow:0 10px 40px rgba(124,108,255,.18)}
.model-card.featured::after{content:"推荐";position:absolute;top:-11px;right:24px;background:linear-gradient(135deg,var(--primary),var(--accent));color:#0b0d12;font-size:11px;font-weight:800;letter-spacing:.1em;padding:5px 12px;border-radius:999px}
.model-tag{font-size:11px;color:var(--accent);font-weight:800;letter-spacing:.14em;text-transform:uppercase;margin-bottom:14px}
.model-name{font-size:22px;font-weight:800;margin-bottom:14px;letter-spacing:-.01em}
.model-desc{color:var(--muted);font-size:14px;line-height:1.85;margin:0 0 20px}
.model-meta{padding-top:18px;border-top:1px dashed var(--line);color:var(--muted);font-size:12.5px;line-height:1.7}

/* ===== FAQ ===== */
.faq-list{display:grid;gap:12px;max-width:860px;margin:0 auto}
.faq-item{background:var(--bg-card);border:1px solid var(--line);border-radius:var(--radius);padding:0 26px;transition:border-color .18s,background .18s}
.faq-item[open]{border-color:var(--primary);background:var(--bg-card-hi)}
.faq-item summary{cursor:pointer;list-style:none;padding:22px 0;font-size:16px;font-weight:700;display:flex;justify-content:space-between;align-items:center;gap:20px;color:var(--text)}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{content:"+";color:var(--accent);font-weight:900;font-size:22px;line-height:1;transition:transform .2s;flex-shrink:0}
.faq-item[open] summary::after{content:"−"}
.faq-item p{margin:0 0 22px;color:var(--muted);font-size:14.5px;line-height:1.9}

/* ===== CTA section ===== */
.cta-section{padding:90px 0 100px;text-align:center;background:linear-gradient(180deg,transparent,rgba(124,108,255,.08))}
.cta-section h2{font-size:clamp(30px,4.5vw,46px);line-height:1.25;margin:0 0 20px;letter-spacing:-.02em;font-weight:800}
.cta-section p{color:var(--muted);font-size:16px;line-height:1.9;max-width:620px;margin:0 auto 36px}

/* ===== Footer ===== */
.site-footer{border-top:1px solid var(--line);background:var(--bg-soft);padding:64px 0 32px;color:var(--muted);font-size:14px}
.footer-inner{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:48px;margin-bottom:48px}
.footer-section h4{color:var(--text);font-size:13px;font-weight:800;letter-spacing:.1em;text-transform:uppercase;margin:0 0 18px}
.footer-section a{display:block;padding:7px 0;color:var(--muted);transition:color .15s}
.footer-section a:hover{color:var(--accent)}
.footer-section p{margin:14px 0 0;line-height:1.8;color:var(--muted);font-size:13px}
.logo-footer{display:inline-block;margin-bottom:4px}
.footer-bottom{padding-top:28px;border-top:1px solid var(--line);font-size:12px;color:var(--muted);line-height:1.8}

/* ===== Guide pages (inner /mcp/ etc.) ===== */
.guide-hero{padding:72px 0 56px;text-align:center}
.guide-hero .hero-inner{text-align:center}
.guide-hero h1{font-size:clamp(32px,5vw,52px);margin:16px 0 20px}
.guide-content{max-width:860px;margin:0 auto;padding:0 28px 90px;display:grid;gap:28px}
.guide-block{background:var(--bg-card);border:1px solid var(--line);border-left:3px solid var(--primary);border-radius:var(--radius);padding:28px 32px}
.guide-block h2{font-size:22px;margin:0 0 12px;font-weight:800;letter-spacing:-.01em}
.guide-block p{margin:0;color:var(--muted);font-size:15px;line-height:1.9}
.guide-content>.cta,.guide-content>.btn{justify-self:start;margin-top:16px}
.faq{margin-top:36px;padding-top:48px;border-top:1px solid var(--line)}
.faq .section-label{color:var(--accent);font-size:12px;letter-spacing:.2em;font-weight:800;text-transform:uppercase;margin-bottom:14px;display:block}
.faq h2{font-size:28px;line-height:1.3;margin:0 0 24px;font-weight:800;letter-spacing:-.02em}

/* ===== Responsive ===== */
@media(max-width:960px){
  .feature-grid,.step-grid,.model-grid,.advantage-grid{grid-template-columns:repeat(2,1fr)}
  .advantage-grid{grid-template-columns:repeat(2,1fr)}
  .footer-inner{grid-template-columns:1fr 1fr;gap:36px}
}
@media(max-width:720px){
  .container{padding-inline:20px}
  .header-inner{height:60px;gap:12px}
  .site-nav{display:none}
  .btn{padding:9px 14px;font-size:13px}
  .btn-large{padding:12px 20px;font-size:14px}
  .hero{padding:60px 0 50px}
  .hero h1{font-size:34px}
  .hero-stats{grid-template-columns:1fr;gap:1px}
  .section{padding:70px 0}
  .section-header{margin-bottom:40px}
  .feature-grid,.step-grid,.model-grid,.advantage-grid{grid-template-columns:1fr}
  .advantage-item{padding:28px 24px}
  .feature-card,.model-card{padding:26px 22px}
  .cta-section{padding:70px 0 80px}
  .cta-section h2{font-size:28px}
  .footer-inner{grid-template-columns:1fr;gap:32px;margin-bottom:36px}
  .guide-content{padding:0 20px 70px}
  .guide-block{padding:22px 24px}
}