/* ============================================================
   RESPONSIVE · 断点适配 / 动效降级
   碳效丰笙 · 丰笙日记官网
   由 style.css 拆分而来，内容与原单文件一致
   ============================================================ */

/* ---------- 响应式 ---------- */
@media (max-width:1024px){
  .about-grid{grid-template-columns:1fr;gap:38px;}
  .about-visual{max-width:520px;}
  .biz-grid,.tech-grid,.social-grid{grid-template-columns:1fr 1fr;}
  .biz-card-feature{order:-1;grid-column:span 2;}
  .scene-grid{grid-template-columns:1fr 1fr;grid-template-rows:none;}
  .scn-card-lead{grid-column:auto;grid-row:auto;}
  .scn-art{min-height:180px;}
  .contact-grid{grid-template-columns:1fr;gap:44px;}
  .qr-card{max-width:400px;}
  .footer-inner{grid-template-columns:1fr 1fr;gap:34px;}
  .hero-motif{right:-90px;width:min(58vw,420px);opacity:.55;}
}
@media (max-width:768px){
  html{scroll-padding-top:68px;}
  .doc-body{padding:30px 22px;margin-top:-20px;}
  .doc-head{padding:64px 0 46px;}
  .doc-body h2{font-size:18px;}
  .doc-body p,.doc-body ul li{font-size:14.5px;}
  .nav-inner{height:66px;}
  .nav-toggle{display:flex;}
  .nav-actions .btn{display:none;}
  .nav-menu{
    position:fixed;top:66px;left:0;right:0;flex-direction:column;align-items:stretch;gap:0;
    background:rgba(255,255,255,.98);backdrop-filter:blur(16px);
    padding:8px 24px 24px;box-shadow:0 18px 40px rgba(9,60,55,.14);
    transform:translateY(-14px);opacity:0;pointer-events:none;transition:.32s;
  }
  .nav-menu.open{transform:none;opacity:1;pointer-events:auto;}
  .nav-menu a{padding:15px 0;border-bottom:1px solid var(--line);font-size:16px;color:var(--ink)!important;}
  .nav-menu a::after{display:none;}
  .nav-cta-mobile{
    display:block;margin-top:18px;background:linear-gradient(135deg,var(--teal),var(--blue));
    color:#fff!important;text-align:center;border-radius:999px;border-bottom:none!important;
  }
  .brand-tag{display:none;}
  .hero{min-height:auto;padding:112px 0 76px;}
  .hero-scroll{display:none;}
  .to-top{right:16px;bottom:20px;width:44px;height:44px;}
  .to-top svg{width:20px;height:20px;}
  .section{padding:70px 0;}
  .sec-head{margin-bottom:40px;}
  .biz-grid,.tech-grid,.social-grid{grid-template-columns:1fr;}
  .biz-card-feature{grid-column:auto;order:0;}
  .core-row{grid-template-columns:1fr;}
  .core-link{padding:4px 0;}
  .core-link::before{background:linear-gradient(180deg,transparent,var(--teal-light),transparent);width:1px;height:26px;margin:0 auto;}
  .core-link span{margin-top:0;}
  .base-flow{gap:8px;}
  .base-flow li{padding:8px 14px;font-size:14px;}
  .scene-grid{grid-template-columns:1fr;grid-template-rows:none;}
  .scn-card-lead{grid-column:auto;grid-row:auto;}
  .scn-art{min-height:190px;}
  .hero-motif{right:-120px;width:min(72vw,340px);opacity:.42;}
  .mvv{grid-template-columns:1fr;gap:26px;}
  .timeline{grid-template-columns:1fr 1fr;gap:22px;}
  .timeline::before{display:none;}
  .tl-item{padding-top:0;padding-left:26px;}
  .tl-item::before{top:6px;left:0;}
  .tl-year{position:static;font-size:22px;margin-bottom:8px;display:block;}
  .footer-inner{grid-template-columns:1fr;gap:30px;}
  .cl-k{min-width:auto;}
}
@media (max-width:420px){
  .container{padding:0 18px;}
  .hero-cta .btn{width:100%;}
  .biz-card,.tech-card,.social-card,.core-card,.about-block{padding-left:22px;padding-right:22px;}
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion:reduce){
  *{animation:none!important;transition:none!important;}
  .js .reveal{opacity:1;transform:none;}
  html{scroll-behavior:auto;}
}