/*  responsive.css — 断点降级（必须最后加载以覆盖前面） */

@media (max-width:1080px){
  .hero-grid{grid-template-columns:1.1fr .9fr;gap:12px}
  .hero-visual{height:min(48vw,460px)}
  .hero h1{font-size:clamp(42px,6vw,64px)}
  .hero .actions{gap:10px}
  .hero .actions .btn{padding:12px 20px}
  .showcase{grid-template-columns:1fr;gap:32px}
  .contact-grid{grid-template-columns:1fr;gap:44px}
  .cell-grid.cols-3{grid-template-columns:repeat(2,1fr)}
  .flow{grid-template-columns:repeat(2,1fr)}
  .stats-row{grid-template-columns:repeat(2,1fr);row-gap:36px}
  .stat:nth-child(3){border-left:none;padding-left:0}
  .stat:nth-child(3),.stat:nth-child(4){border-top:1px solid rgba(255,255,255,.22);padding-top:32px}
}

@media (max-width:720px){
  /* 导航：折叠为静态列；因脱离深色首屏，恒为深底以保证文字对比 */
  .nav{position:static;flex-wrap:wrap;height:auto;min-height:var(--nav-h)}
  .nav,.nav.scrolled{
    background:var(--navy);border-bottom:1px solid var(--line-dark);color:#dfe6f2;
    backdrop-filter:none;-webkit-backdrop-filter:none;   /* 恒深底，无需毛玻璃 */
  }
  .brand-name,.scrolled .brand-name{color:#fff}
  .brand-mark,.scrolled .brand-mark{color:var(--accent-soft)}
  .nav-links{
    display:none;width:100%;order:3;
    flex-direction:column;gap:0;
  }
  .nav-links.open{display:block}
  .nav-links li{border-top:1px solid var(--line-dark)}
  .nav-links a{display:block;padding:14px 0;font-size:15px}
  .nav-links a::after{display:none}
  .brand{padding:9px 0;gap:10px}
  .brand-logo{width:138px}
  .brand-cn{font-size:10px;letter-spacing:.18em}
  .nav-toggle{display:block}
  section{scroll-margin-top:0}

  .hero{padding-top:0;min-height:calc(100vh - var(--nav-h));min-height:calc(100svh - var(--nav-h))}
  .hero-grid{grid-template-columns:1fr;gap:0;padding-top:20px;padding-bottom:24px}
  .hero-visual{display:none}
  .hero .kicker{font-size:10px;letter-spacing:.13em;margin-bottom:12px}
  .hero h1{font-size:clamp(38px,9.6vw,58px);margin:12px 0 18px}
  .hero .lede{font-size:13px;line-height:1.9;margin-bottom:22px;max-width:48ch}
  .hero .actions{margin-bottom:24px}
  .proof{padding-top:18px}
  .hero .actions .btn{flex:1;justify-content:center}
  .proof{grid-template-columns:repeat(3,1fr);gap:12px}
  .cell-grid.cols-2,.cell-grid.cols-3{grid-template-columns:1fr}
  .feats{grid-template-columns:1fr}
  .flow{grid-template-columns:1fr}
  .stats-row{grid-template-columns:1fr 1fr;gap:28px 16px;padding:40px var(--pad-x)}
  .stat + .stat{border-left:none;padding-left:0}
  .stat:nth-child(3),.stat:nth-child(4){border-top:none;padding-top:0}
  .contact-list div{grid-template-columns:1fr;gap:2px;padding:16px 0}
}

/* 笔记本短屏：压缩纵向留白，让首屏内容完整落在视口内。 */
@media (min-width:721px) and (max-height:780px){
  .hero-grid{padding-top:24px;padding-bottom:24px}
  .hero h1{font-size:clamp(42px,5.4vw,66px);margin-bottom:20px}
  .hero .lede{margin-bottom:24px}
  .hero .actions{margin-bottom:32px}
  .proof{padding-top:20px}
  .hero-visual{height:min(65vh,500px)}
}

/* 无障碍：尊重系统减少动效偏好 */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:.01ms!important;animation-duration:.01ms!important}
}

/* 紧凑手机宽度下优先呈现完整星标与字标。 */
@media (max-width:360px){
  .brand-logo{width:131.5px}
  .brand-cn{display:none}
}