/* ============================================================
   智启鸿云官网 · 全站样式 · 新潮编辑风（demo4 深化版）
   设计语言：超大字排版 / 极光渐变 / 纸感-深色反差 / 衬线数字点缀
   ============================================================ */
:root{
  --ink:#141416; --paper:#f6f3ec; --soft:#efeae0; --muted:#6f6a60;
  --dark:#0d0d11; --dark2:#15151b; --d-text:#f2efe8; --d-muted:#9b968c;
  --line-paper:#e2dccc; --line-dark:rgba(255,255,255,.14);
  --a1:#4f7cff; --a2:#a06bff; --a3:#2fd4c4; --amber:#ffb14d;
  --grad:linear-gradient(100deg,#4f7cff 0%,#a06bff 55%,#2fd4c4 100%);
  --serif:Georgia,"Times New Roman","STSong",serif;
  --mono:ui-monospace,"Cascadia Mono",Consolas,monospace;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:"PingFang SC","Microsoft YaHei","Segoe UI",system-ui,sans-serif;color:var(--ink);background:var(--paper);line-height:1.65;-webkit-font-smoothing:antialiased}
a{text-decoration:none;color:inherit}
img{max-width:100%;display:block}
html,body{overflow-x:clip}
body{-webkit-tap-highlight-color:transparent}
.wrap{max-width:1180px;margin:0 auto;padding:0 26px}
.g{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}

/* ---------- 按钮 ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;font-size:14px;font-weight:700;padding:12px 26px;border-radius:99px;cursor:pointer;border:none;transition:.25s;letter-spacing:.02em}
.btn-lg{padding:15px 34px;font-size:15px}
.btn-sm{padding:9px 18px;font-size:12.5px}
.btn-grad{background:var(--grad);color:#fff}
.btn-grad:hover{filter:brightness(1.12);transform:translateY(-1px)}
.btn-ink{background:var(--ink);color:#fff}
.btn-ink:hover{background:#000;transform:translateY(-1px)}
.btn-glass{background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.2);color:#fff}
.btn-glass:hover{background:rgba(255,255,255,.16)}
.btn-line{border:1.5px solid var(--ink);color:var(--ink);background:transparent}
.btn-line:hover{background:var(--ink);color:var(--paper)}

/* ---------- 导航（全站吸顶深色） ---------- */
nav{position:sticky;top:0;z-index:100;background:rgba(13,13,17,.92);backdrop-filter:blur(12px);border-bottom:1px solid var(--line-dark)}
.nav-in{display:flex;align-items:center;gap:34px;height:66px}
.logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:17px;color:#fff;letter-spacing:.04em;white-space:nowrap}
.nav-links{display:flex;gap:26px;font-size:13.5px;color:rgba(255,255,255,.68)}
.nav-links a{padding:6px 0;position:relative}
.nav-links a:hover{color:#fff}
.nav-links a.cur{color:#fff}
.nav-links a.cur::after{content:"";position:absolute;left:0;right:0;bottom:-2px;height:2px;background:var(--grad);border-radius:1px}
.nav-cta{margin-left:auto;display:flex;gap:10px;align-items:center}
.menu-btn{display:none;cursor:pointer;width:38px;height:38px;border-radius:8px;border:1px solid var(--line-dark);background:transparent;flex-direction:column;align-items:center;justify-content:center;gap:5px}
.pc-only{}
.m-only{display:none}
.menu-btn span{display:block;width:16px;height:1.5px;background:#fff}
#menu-toggle{display:none}
@media(max-width:1060px){
  .menu-btn{display:flex}
  .nav-links{display:none;position:absolute;top:66px;left:0;right:0;background:rgba(13,13,17,.98);flex-direction:column;gap:0;padding:10px 26px 18px;border-bottom:1px solid var(--line-dark)}
  .nav-links a{padding:12px 0;font-size:15px;border-bottom:1px solid rgba(255,255,255,.06)}
  #menu-toggle:checked ~ .nav-links{display:flex}
}

/* ---------- 页面 Hero（深色 + 极光） ---------- */
.page-hero{position:relative;background:var(--dark);color:#fff;padding:110px 0 84px;overflow:hidden}
.page-hero.home{padding:150px 0 110px;min-height:78vh;display:flex;align-items:center}
.aurora{position:absolute;border-radius:50%;filter:blur(90px);opacity:.5;pointer-events:none}
.aurora.a{width:560px;height:560px;background:#3b5bdb;top:-180px;left:-120px;animation:drift 16s ease-in-out infinite alternate}
.aurora.b{width:480px;height:480px;background:#7048e8;top:-80px;right:-140px;animation:drift 20s ease-in-out infinite alternate-reverse}
.aurora.c{width:420px;height:420px;background:#0ca678;bottom:-200px;left:38%;opacity:.3;animation:drift 24s ease-in-out infinite alternate}
.aurora.small{width:320px;height:320px;filter:blur(70px)}
@keyframes drift{from{transform:translate(0,0) scale(1)}to{transform:translate(60px,40px) scale(1.15)}}
.grain{position:absolute;inset:0;opacity:.07;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)'/%3E%3C/svg%3E")}
.page-hero-in{position:relative}
.kicker{font-family:var(--mono);font-size:12px;letter-spacing:.2em;color:rgba(255,255,255,.5);display:block;margin-bottom:22px}
.page-hero h1{font-size:clamp(34px,6vw,72px);line-height:1.14;font-weight:900;letter-spacing:.01em}
.page-hero h1 .outline{color:transparent;-webkit-text-stroke:1.5px rgba(255,255,255,.55)}
.page-hero p.lead{margin-top:26px;color:#c9c5bd;font-size:16.5px;max-width:560px}
.page-hero .hero-btns{display:flex;gap:14px;margin-top:36px;flex-wrap:wrap}
.crumb{font-family:var(--mono);font-size:11.5px;color:rgba(255,255,255,.4);letter-spacing:.1em;margin-top:34px}
.crumb a:hover{color:#fff}

/* 首页大标题 */
.home h1{font-size:clamp(44px,8vw,104px)}
.hero-side{position:absolute;right:0;bottom:-8px;text-align:right;font-size:12px;color:rgba(255,255,255,.35);line-height:2.1;display:none}
@media(min-width:1100px){.hero-side{display:block}}

/* ---------- 跑马灯 ---------- */
.marquee{background:var(--ink);color:#f5f2ea;padding:16px 0;overflow:hidden}
.marquee-in{display:flex;width:max-content;animation:scroll 26s linear infinite}
.marquee span{display:inline-flex;align-items:center;gap:26px;padding-right:26px;font-size:14px;font-weight:600;letter-spacing:.06em;white-space:nowrap}
.marquee i{font-style:normal;color:var(--amber)}
@keyframes scroll{to{transform:translateX(-50%)}}

/* ---------- 视频感首屏（方案A） ---------- */
.hero-video{position:absolute;inset:0;background:#0b0f1c;overflow:hidden;z-index:0}
.hero-video video{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:0;transition:opacity 1.1s ease;transform:scale(1.03)}
.hero-video video.instant{transition:none!important}
.hero-video video.active{opacity:1;animation:kenburns 8.8s linear forwards}
.hero-video video.freeze{animation:none}
.hero-video canvas{display:none;position:absolute;inset:0;width:100%;height:100%}
.hero-video.fallback video{display:none}
.hero-video.fallback canvas{display:block}
@keyframes kenburns{from{transform:scale(1.03)}to{transform:scale(1.11)}}
.hero-screen{position:relative;background:var(--dark);color:#fff;min-height:calc(100vh - 66px);display:flex;align-items:center;justify-content:center;overflow:hidden;padding:96px 0 130px}
#heroCanvas{position:absolute;inset:0;width:100%;height:100%;display:block}
.hero-veil{position:absolute;inset:0;z-index:1;background:linear-gradient(180deg,rgba(13,13,17,.52),rgba(13,13,17,.18) 42%,rgba(13,13,17,.66)),radial-gradient(ellipse 60% 50% at 50% 42%,transparent,rgba(13,13,17,.38))}
.hero-center{position:relative;z-index:2;text-align:center;max-width:880px;padding:0 24px}
.hero-center .kicker{display:block;margin-bottom:26px;color:rgba(255,255,255,.5)}
.hero-center h1{font-size:clamp(52px,8.5vw,116px);font-weight:900;line-height:1.04;letter-spacing:.08em;color:#fff;text-shadow:0 6px 40px rgba(0,0,0,.45)}
.hero-center .sub{margin-top:16px;font-size:clamp(15px,1.9vw,21px);font-weight:600;letter-spacing:.34em;text-indent:.34em;color:#e8e4da;text-shadow:0 2px 18px rgba(0,0,0,.5)}
.search-card{margin:44px auto 0;max-width:640px;background:#fff;border-radius:20px;padding:16px 18px 15px;text-align:left;box-shadow:0 30px 90px rgba(0,0,0,.5)}
.search-head{display:flex;align-items:center;gap:8px;font-size:12.5px;color:var(--muted);padding:0 4px 11px}
.search-head svg{color:var(--a1)}
.search-head b{color:var(--ink)}
.search-head span{margin-left:auto;font-size:11.5px;color:#a39d90}
.search-row{display:flex;gap:10px}
.search-row input{flex:1;min-width:0;border:1.5px solid var(--line-paper);border-radius:12px;padding:12px 16px;font-size:15px;font-family:inherit;color:var(--ink);outline:none;transition:.2s}
.search-row input:focus{border-color:var(--ink)}
.search-row .btn{flex:none}
.quick-tags{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px}
.quick-tags button{font-size:12.5px;color:#4c473e;background:var(--soft);border:1px solid var(--line-paper);border-radius:99px;padding:6px 14px;cursor:pointer;font-family:inherit;transition:.2s}
.quick-tags button:hover{background:#141416;color:#fff;border-color:#141416}
.hero-chips{position:absolute;left:0;right:0;bottom:36px;z-index:3;display:flex;justify-content:center;gap:14px;flex-wrap:wrap;padding:0 24px}
.hero-chip{display:inline-flex;align-items:center;gap:10px;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.22);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border-radius:99px;padding:13px 24px;color:#fff;font-weight:700;font-size:14px;letter-spacing:.02em;transition:.25s;white-space:nowrap}
.hero-chip svg{color:#2fd4c4;flex:none}
.hero-chip:hover{background:rgba(255,255,255,.17);transform:translateY(-2px)}

/* ---------- 通用 Section ---------- */
section{padding:96px 0}
.sec.dark{background:var(--dark);color:var(--d-text)}
.sec.soft{background:var(--soft)}
.sec-head{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;margin-bottom:52px;flex-wrap:wrap}
.sec-head h2{font-size:clamp(30px,4.4vw,50px);font-weight:900;line-height:1.16;letter-spacing:.01em}
.sec-head h2 .sub-line{display:block;font-size:.42em;font-weight:600;color:var(--muted);margin-top:10px;letter-spacing:.02em}
.sec.dark .sec-head h2 .sub-line{color:var(--d-muted)}
.sec-head .idx{font-family:var(--mono);font-size:12px;color:rgba(0,0,0,.32);letter-spacing:.2em}
.sec.dark .sec-head .idx{color:rgba(255,255,255,.3)}

/* ---------- 首页业务索引列表 ---------- */
.svc-list{border-top:1.5px solid #141416}
.svc-row{display:grid;grid-template-columns:70px 1.1fr 1.6fr auto;gap:28px;align-items:center;padding:34px 6px;border-bottom:1.5px solid #141416;transition:.25s}
.svc-row .no{font-family:var(--serif);font-size:30px;font-style:italic;color:rgba(0,0,0,.24);transition:.25s}
.svc-row h3{font-size:23px;font-weight:800}
.svc-row .tags{font-size:12.5px;margin-top:8px;opacity:.55}
.svc-row p{font-size:14px;opacity:.75;max-width:480px}
.svc-row .arr{font-size:26px;font-weight:300;transition:.25s}
@media(hover:hover){
  .svc-row:hover{background:#141416;color:var(--paper);padding-left:22px;padding-right:14px}
  .svc-row:hover .no{color:var(--amber)}
  .svc-row:hover .arr{transform:translateX(8px);color:#2fd4c4}
}

/* ---------- 卡片网格（服务总览 / 详情内容块） ---------- */
.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.card{background:#fff;border:1px solid var(--line-paper);border-radius:18px;padding:32px 30px;transition:.25s;position:relative;overflow:hidden}
@media(hover:hover){
  .card:hover{transform:translateY(-4px);box-shadow:0 18px 44px rgba(20,20,22,.09)}
}
.card .c-ico{width:44px;height:44px;border-radius:12px;background:#141416;color:#fff;display:grid;place-items:center;margin-bottom:18px}
.card .c-ico.alt{background:var(--grad)}
.card h3{font-size:18px;font-weight:800;margin-bottom:10px}
.card p{font-size:13.5px;color:var(--muted)}
.card ul{list-style:none;margin-top:14px}
.card li{font-size:13px;color:#4c473e;padding:4px 0 4px 18px;position:relative}
.card li::before{content:"";position:absolute;left:0;top:11px;width:8px;height:8px;border-radius:3px;background:var(--grad)}
.card .c-no{position:absolute;top:20px;right:24px;font-family:var(--serif);font-style:italic;font-size:26px;color:rgba(0,0,0,.1)}
.sec.dark .card{background:var(--dark2);border-color:var(--line-dark)}
.sec.dark .card p{color:var(--d-muted)}
.sec.dark .card li{color:#c5c0b6}
.sec.dark .card .c-no{color:rgba(255,255,255,.12)}
.sec.dark .card .c-ico{background:#fff;color:#141416}
.sec.dark .card .c-ico.alt{background:var(--grad);color:#fff}

/* ---------- 数字亮点带 ---------- */
.stat-band{display:grid;grid-template-columns:repeat(4,1fr);border:1.5px solid var(--ink);border-radius:18px;overflow:hidden;background:#fff}
.stat-band .stat{padding:28px 26px 24px;border-right:1.5px solid var(--ink)}
.stat-band .stat:last-child{border-right:none}
.stat-band .stat:nth-child(2n){background:var(--soft)}
.stat .v{font-size:32px;font-weight:800;color:var(--ink);line-height:1.2}
.stat .v em{font-style:normal;font-size:17px;color:var(--a1);margin-left:2px}
.stat .l{font-size:13px;color:var(--muted);margin-top:6px}
.stat-band.on-dark{background:var(--dark2);border-color:var(--line-dark)}
.stat-band.on-dark .stat{border-color:var(--line-dark)}
.stat-band.on-dark .stat:nth-child(2n){background:#191922}
.stat-band.on-dark .stat .v{color:#fff}
.stat-band.on-dark .stat .l{color:var(--d-muted)}

/* ---------- 流程 ---------- */
.flow{display:grid;grid-template-columns:repeat(5,1fr);gap:26px}
.fstep{border-top:2px solid #141416;padding-top:18px}
.sec.dark .fstep{border-top-color:rgba(255,255,255,.5)}
.fstep .n{font-family:var(--serif);font-style:italic;font-size:15px;color:#b3a06b}
.sec.dark .fstep .n{color:var(--amber)}
.fstep h4{font-size:16.5px;font-weight:800;margin:8px 0 6px}
.fstep p{font-size:12.5px;color:var(--muted)}
.sec.dark .fstep p{color:var(--d-muted)}

/* ---------- 案例区（编辑风不对称网格） ---------- */
.case-grid{display:grid;grid-template-columns:repeat(12,1fr);gap:22px}
.case{border:1px solid var(--line-dark);border-radius:20px;padding:30px;position:relative;overflow:hidden;background:var(--dark2);transition:.3s;color:var(--d-text);display:flex;flex-direction:column}
@media(hover:hover){
  .case:hover{transform:translateY(-6px);border-color:rgba(255,255,255,.3)}
}
.case::before{content:"";position:absolute;width:220px;height:220px;border-radius:50%;filter:blur(70px);opacity:.26;top:-70px;right:-60px;background:var(--a1)}
.case.big{grid-column:span 7;min-height:280px;justify-content:flex-end}
.case.sm{grid-column:span 5}
.case.s3{grid-column:span 4}
.case .no{font-family:var(--serif);font-style:italic;font-size:44px;color:rgba(255,255,255,.12);position:absolute;top:18px;left:24px}
.case-tag{display:inline-block;font-size:11.5px;padding:4px 12px;border-radius:99px;border:1px solid rgba(255,255,255,.22);color:#cfcabf;margin-bottom:14px;width:fit-content;position:relative}
.case h3{font-size:20px;font-weight:700;position:relative}
.case.big h3{font-size:26px}
.case p{font-size:13.5px;color:var(--d-muted);margin-top:10px;position:relative;max-width:480px}
.case .metric{margin-top:auto;padding-top:22px;font-family:var(--serif);font-style:italic;font-size:17px;color:#2fd4c4;position:relative}
.case .go{position:absolute;top:22px;right:24px;font-size:18px;color:rgba(255,255,255,.4);transition:.25s}
@media(hover:hover){
  .case:hover .go{color:#2fd4c4;transform:translate(3px,-3px)}
}
.case-filters{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:30px}
.case-filters span{font-size:12.5px;color:var(--d-muted);border:1px solid var(--line-dark);padding:5px 15px;border-radius:99px}
.case-filters span.on{background:var(--grad);color:#fff;font-weight:700;border-color:transparent}

/* ---------- 案例详情 ---------- */
.dl{list-style:none;border-top:1.5px solid var(--line-paper)}
.dl li{display:grid;grid-template-columns:200px 1fr;gap:24px;padding:18px 4px;border-bottom:1.5px solid var(--line-paper);font-size:14.5px}
.dl li b{font-weight:800}
.dl li span{color:var(--muted)}
.quote{border-left:3px solid var(--ink);padding:6px 0 6px 26px;font-family:var(--serif);font-style:italic;font-size:20px;line-height:1.8;color:#3a362e}
.quote footer{font-family:"PingFang SC",sans-serif;font-style:normal;font-size:13px;color:var(--muted);margin-top:12px}

/* ---------- 关于页 ---------- */
.values{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.value{background:#fff;border:1px solid var(--line-paper);border-radius:18px;padding:34px 30px}
.value .v-no{font-family:var(--serif);font-style:italic;font-size:28px;color:rgba(0,0,0,.16)}
.value h3{font-size:19px;font-weight:800;margin:14px 0 8px}
.value p{font-size:13.5px;color:var(--muted)}
.timeline{position:relative;padding-left:34px}
.timeline::before{content:"";position:absolute;left:8px;top:8px;bottom:8px;width:2px;background:var(--line-paper)}
.tl-item{position:relative;padding:0 0 34px}
.tl-item::before{content:"";position:absolute;left:-32px;top:8px;width:12px;height:12px;border-radius:50%;background:var(--grad)}
.tl-item .t{font-family:var(--serif);font-style:italic;font-size:17px;color:#b3a06b}
.tl-item h4{font-size:16.5px;font-weight:800;margin:4px 0 4px}
.tl-item p{font-size:13.5px;color:var(--muted);max-width:560px}

/* ---------- 表单（占位） ---------- */
.form{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.form .full{grid-column:1/-1}
.form label{display:block;font-size:13px;font-weight:700;margin-bottom:8px}
.form label i{font-style:normal;color:#c0392b}
.form input,.form select,.form textarea{width:100%;font:inherit;font-size:14px;padding:13px 16px;border:1.5px solid var(--line-paper);border-radius:12px;background:#fff;color:var(--ink);transition:.2s;outline:none}
.form input:focus,.form select:focus,.form textarea:focus{border-color:var(--ink)}
.form textarea{min-height:120px;resize:vertical}
.form-note{grid-column:1/-1;font-size:12.5px;color:var(--muted);background:var(--soft);border:1px dashed var(--line-paper);border-radius:10px;padding:10px 16px}
.contact-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:20px;align-items:start}
@media(max-width:900px){.contact-grid{grid-template-columns:1fr}}
.info-card{background:#fff;border:1px solid var(--line-paper);border-radius:18px;padding:28px;display:flex;gap:16px;align-items:flex-start}
.info-card .ic{width:42px;height:42px;border-radius:12px;background:#141416;color:#fff;display:grid;place-items:center;flex:none}
.info-card h4{font-size:15.5px;font-weight:800}
.info-card p{font-size:14px;color:var(--muted);margin-top:4px}
.qr-box{width:150px;height:150px;border-radius:16px;background:repeating-conic-gradient(#e8e4d9 0 25%,#fff 0 50%) 0 0/22px 22px;border:1.5px solid var(--line-paper);display:grid;place-items:center}
.qr-box span{background:#fff;border:1px solid var(--line-paper);border-radius:10px;padding:8px 12px;font-size:12px;color:var(--muted)}

/* ---------- FAQ ---------- */
.faq{border-top:1.5px solid var(--line-paper)}
.faq details{border-bottom:1.5px solid var(--line-paper)}
.faq summary{cursor:pointer;list-style:none;display:flex;justify-content:space-between;align-items:center;gap:20px;padding:22px 4px;font-size:16px;font-weight:700}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";font-size:22px;font-weight:400;color:var(--muted);transition:.2s}
.faq details[open] summary::after{transform:rotate(45deg)}
.faq .a{padding:0 4px 24px;font-size:14px;color:var(--muted);max-width:760px}

/* ---------- 大字 CTA ---------- */
.cta-big{text-align:center;padding:20px 0 0}
.cta-big h2{font-size:clamp(34px,6vw,72px);font-weight:900;line-height:1.18}
.cta-big p{color:var(--muted);margin:22px 0 34px;font-size:15.5px}
.sec.dark .cta-big p{color:var(--d-muted)}
.cta-big .btns{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}

/* ---------- 页脚 ---------- */
footer{background:var(--dark);color:#8f8a80;font-size:13px;padding:56px 0 32px}
.foot-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:36px;padding-bottom:40px;border-bottom:1px solid var(--line-dark)}
.foot-grid h5{color:#fff;font-size:13.5px;font-weight:700;margin-bottom:16px;letter-spacing:.04em}
.foot-grid a{display:block;padding:4.5px 0;color:#8f8a80}
.foot-grid a:hover{color:#fff}
.foot-brand{display:flex;align-items:center;gap:10px;color:#fff;font-weight:800;font-size:16px;margin-bottom:14px}
.foot-brand svg{flex:none}
.foot-grid p{font-size:12.5px;line-height:1.9}
.foot-base{display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap;padding-top:24px;font-size:12px;color:#6b665c}
.foot-base a{color:#8f8a80}
.foot-base a:hover{color:#fff}

/* ---------- 响应式 ---------- */
@media(max-width:1060px){
  .svc-row{grid-template-columns:50px 1fr auto;row-gap:10px}
  .svc-row p{grid-column:2/4}
  .case.big,.case.sm,.case.s3{grid-column:span 12}
  .case.sm:last-child{grid-column:span 12}
  .flow{grid-template-columns:repeat(2,1fr)}
  .grid-3{grid-template-columns:1fr 1fr}
  .values{grid-template-columns:1fr}
  .stat-band{grid-template-columns:repeat(2,1fr)}
  .stat-band .stat:nth-child(2n){border-right:none}
  .stat-band .stat:nth-child(-n+2){border-bottom:1.5px solid var(--ink)}
  .stat-band.on-dark .stat:nth-child(-n+2){border-bottom-color:var(--line-dark)}
  .foot-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:640px){
  section{padding:56px 0}
  /* 导航：双 CTA 保留，尺寸收紧 */
  .nav-in{gap:10px;height:60px}
  .logo{font-size:16px}
  .nav-cta{gap:8px}
  .nav-cta .btn{padding:8px 10px;font-size:11.5px;white-space:nowrap}
  .pc-only{display:none}
  .m-only{display:inline}
  .menu-btn{width:34px;height:34px}
  .nav-links{top:60px}
  /* 首屏 */
  .page-hero{padding:80px 0 60px}
  .page-hero.home{min-height:auto;padding:104px 0 80px}
  .page-hero h1{font-size:clamp(30px,9vw,40px)}
  .home h1{font-size:clamp(32px,10.5vw,44px)}
  .page-hero h1 .outline{-webkit-text-stroke-width:1px}
  .page-hero p.lead{font-size:15px;margin-top:20px}
  .hero-btns{gap:10px;margin-top:28px}
  .hero-btns .btn{flex:1;min-width:0;padding:13px 16px;font-size:14px}
  .crumb{margin-top:24px}
  /* 性能：关闭极光动画、缩小模糊半径 */
  .aurora.a,.aurora.b,.aurora.c{animation:none}
  .aurora,.aurora.small{filter:blur(55px)}
  .aurora.a{width:320px;height:320px}
  .aurora.b{width:280px;height:280px}
  .aurora.c{opacity:.2}
  /* 区块标题 */
  .sec-head{margin-bottom:36px}
  .sec-head h2{font-size:clamp(26px,8vw,34px)}
  .cta-big h2{font-size:clamp(28px,8.5vw,36px)}
  .cta-big .btn{flex:1;min-width:0;padding:13px 18px;font-size:14px}
  /* 布局收紧 */
  .grid-3,.grid-2,.flow{grid-template-columns:1fr}
  .flow{gap:16px}
  .dl li{grid-template-columns:1fr;gap:4px}
  .stat-band .stat{padding:20px 16px 18px}
  .stat .v{font-size:26px}
  /* 首页业务列表 */
  .svc-row{grid-template-columns:44px 1fr auto;padding:24px 2px}
  .svc-row .no{font-size:24px}
  .svc-row h3{font-size:19px}
  /* 案例卡 */
  .case{padding:24px 20px}
  .case .no{font-size:34px}
  .case h3{font-size:18px}
  .case.big h3{font-size:21px}
  .case.big{min-height:0}
  .case-filters span{font-size:12px;padding:4px 12px}
  /* 跑马灯 */
  .marquee{padding:12px 0}
  .marquee span{font-size:13px}
  /* 表单：16px 防 iOS 聚焦缩放 */
  .form{grid-template-columns:1fr}
  .form input,.form select,.form textarea{font-size:16px}
  .info-card{padding:20px}
  /* 页脚 */
  .foot-grid{grid-template-columns:1fr 1fr;gap:24px;padding-bottom:30px}
  .foot-grid>div:first-child{grid-column:1/-1}
  footer{padding:44px 0 28px}
  /* 触屏按下反馈（替代悬停效果） */
  .svc-row:active{background:#141416;color:var(--paper)}
  .card:active,.case:active{transform:scale(.985)}
  .hero-side{display:none}
  /* 视频感首屏（移动端） */
  .hero-screen{min-height:auto;padding:110px 0 40px}
  .hero-center h1{font-size:clamp(42px,12.5vw,58px)}
  .hero-center .sub{font-size:13.5px;letter-spacing:.22em;text-indent:.22em}
  .search-card{margin-top:30px;padding:12px 12px 11px;border-radius:16px}
  .search-head{padding:0 2px 9px}
  .search-head span{display:none}
  .search-row input{font-size:16px;padding:11px 12px;border-radius:10px}
  .search-row .btn{padding:11px 14px;font-size:13px}
  .quick-tags button{font-size:12px;padding:5px 11px}
  .hero-chips{position:static;margin-top:38px;gap:10px}
  .hero-chip{padding:11px 16px;font-size:13px;gap:8px}
}
@media(max-width:380px){
  .foot-grid{grid-template-columns:1fr}
  .stat-band{grid-template-columns:1fr 1fr}
}