html,body{overflow-x:hidden}

@media(max-width:900px){
  .site-header{position:fixed;width:100%}
  body{padding-top:68px}
  .nav{height:68px;position:relative}
  .mobile-menu{display:inline-flex;align-items:center;gap:8px;min-width:76px;min-height:44px;justify-content:center;border:1px solid #dbe3ef;border-radius:999px;background:#fff;color:#0f172a;font:inherit;font-size:14px;font-weight:800;cursor:pointer}
  .mobile-menu b{font-size:17px;line-height:1}
  .mobile-menu[aria-expanded="true"] b{transform:rotate(90deg)}
  .nav-links{display:none;position:absolute;top:calc(100% + 1px);left:0;right:0;padding:12px 14px 16px;gap:4px;flex-direction:column;align-items:stretch;background:rgba(255,255,255,.98);border:1px solid #e2e8f0;border-top:0;border-radius:0 0 18px 18px;box-shadow:0 20px 45px rgba(15,23,42,.16)}
  .nav-links.is-open{display:flex}
  .nav-links a,.nav-links a:not(.nav-cta){display:flex;align-items:center;min-height:48px;padding:10px 14px;border-radius:11px;font-size:15px}
  .nav-links a:hover{color:#1d4ed8;background:#eff6ff}
  .nav-links .nav-cta{justify-content:center;margin-top:6px;color:#fff;background:#2563eb}
  .nav-links .nav-cta:hover,.nav-links .nav-cta:focus-visible,.nav-links .nav-cta:active,.nav-links .nav-cta[aria-current="page"]{color:#fff;background:#1d4ed8}
  .hero-grid{min-height:auto;grid-template-columns:1fr;padding:46px 0;gap:30px}
  .hero h1{font-size:38px}
  .hero-media img{height:340px}
  .grid-4{grid-template-columns:repeat(2,1fr)}
  .grid-3{grid-template-columns:repeat(2,1fr)}
  .actions .btn{min-height:46px}
  .section{padding:70px 0}
}

@media(max-width:640px){
  .wrap{width:min(100% - 28px,var(--max))}
  .brand{font-size:17px;white-space:nowrap}
  .brand-mark{width:32px;height:32px}
  .brand-cn{display:none}
  .nav-cta{font-size:13px;padding:9px 14px;white-space:nowrap}
  .hero-grid{padding:38px 0;gap:24px}
  .eyebrow{font-size:11px;margin-bottom:10px}
  .hero h1{font-size:31px;letter-spacing:-.5px;margin-bottom:14px}
  .hero .lead{font-size:15px;line-height:1.75}
  .actions{display:grid;grid-template-columns:1fr;margin-top:22px}
  .actions .btn{width:100%}
  .hero-media{border-radius:17px}
  .hero-media img{height:230px}
  .media-label{right:10px;bottom:10px}
  .breadcrumbs{padding:14px 0;white-space:nowrap;overflow-x:auto}
  .section{padding:52px 0}
  .section-head{margin-bottom:26px}
  .section-head h2{font-size:26px}
  .section-head p{font-size:15px}
  .grid-2,.grid-3,.grid-4,.footer-grid,.form-card{grid-template-columns:1fr}
  .cards-grid,.cards-grid.three,.cards-grid.two{grid-template-columns:1fr!important}
  .cards-grid{gap:12px}
  .cards-grid .card{min-width:0}
  .cards-grid .metric b{line-height:1.35;overflow-wrap:anywhere}
  .card{padding:20px}
  .field.full{grid-column:auto}
  .cta-band{padding:26px 22px;align-items:stretch;flex-direction:column}
  .cta-band h2{font-size:24px}
  .cta-band .btn{width:100%;min-height:46px}
  .cta-band:not(.guide-cta){padding:22px 18px;border-radius:16px;gap:18px}
  .cta-band:not(.guide-cta) h2{font-size:22px}
  .cta-band:not(.guide-cta) .btn{min-height:48px;border-radius:14px}
  .guide-cta-section{padding-top:34px;padding-bottom:44px}
  .guide-cta{padding:22px 18px;border-radius:16px;gap:18px}
  .guide-cta h2{font-size:22px}
  .guide-cta .btn{border-radius:14px;min-height:48px}
  .spec-table{display:block;overflow:hidden}
  .spec-table tbody{display:block}
  .spec-table tr{display:grid;grid-template-columns:minmax(92px,32%) 1fr}
  .spec-table th,.spec-table td{width:auto;padding:12px 10px;overflow-wrap:anywhere}
  .footer{padding:38px 0 20px}
  .copyright{margin-top:26px}
  .article h2{font-size:25px}
  .case-photo{height:210px}

  /* 选型指南：窄屏阅读与触控优化 */
  .breadcrumbs+.section{padding-top:30px;padding-bottom:48px}
  .breadcrumbs+.section .article{width:calc(100% - 28px);max-width:none;margin-inline:auto}
  .breadcrumbs+.section .article .kicker{margin-bottom:12px}
  .breadcrumbs+.section .article h1{font-size:30px;line-height:1.25;letter-spacing:-.5px}
  .breadcrumbs+.section .article>h1+p{margin-top:14px;font-size:16px;line-height:1.75}
  .breadcrumbs+.section .article-meta{display:grid;gap:5px;margin-top:14px;line-height:1.55}
  .breadcrumbs+.section .article .case-photo{margin-top:22px!important;border-radius:16px;aspect-ratio:16/10}
  .breadcrumbs+.section .article .case-photo img{height:100%;object-fit:cover}
  .breadcrumbs+.section .article h2{margin:36px 0 12px;font-size:23px;line-height:1.35}
  .breadcrumbs+.section .article p,.breadcrumbs+.section .article li{font-size:15px;line-height:1.8}
  .breadcrumbs+.section .article ul{padding-left:20px}
  .breadcrumbs+.section .article li+li{margin-top:6px}
  .breadcrumbs+.section .spec-table{margin:16px 0;border:0;border-radius:0;background:transparent}
  .breadcrumbs+.section .spec-table tr{display:block;margin-bottom:10px;padding:14px 15px;border:1px solid var(--line);border-radius:14px;background:#fff;box-shadow:0 5px 16px rgba(15,23,42,.04)}
  .breadcrumbs+.section .spec-table th,.breadcrumbs+.section .spec-table td{display:block;padding:0;border:0;background:transparent}
  .breadcrumbs+.section .spec-table th{margin-bottom:5px;color:var(--ink);font-size:15px}
  .breadcrumbs+.section .spec-table td{font-size:14px;line-height:1.65}
  .breadcrumbs+.section .faq{gap:10px}
  .breadcrumbs+.section .faq details{padding:15px 16px}
  .breadcrumbs+.section .faq summary{font-size:15px;line-height:1.55}
}

@media(max-width:380px){
  .wrap{width:min(100% - 22px,var(--max))}
  .brand{font-size:15px}
  .brand-mark{margin-right:7px}
  .nav-cta{padding:8px 11px}
  .hero h1{font-size:28px}
  .hero-media img{height:205px}
  .breadcrumbs+.section .article h1{font-size:27px}
  .breadcrumbs+.section .article h2{font-size:21px}
}