/* ============================================================
   上云端官网 · 纯 HTML/CSS/JS
   主色：深蓝 #0F52A8 / 亮蓝 #1A7BE0 / 青 #35C6F4
   ============================================================ */
:root{
  --blue:#0F52A8;
  --blue-deep:#081C3A;
  --bright:#1A7BE0;
  --cyan:#35C6F4;
  --ink:#12263F;
  --muted:#5A6B84;
  --line:#E3EBF6;
  --bg:#FFFFFF;
  --bg-alt:#F3F7FC;
  --shadow:0 10px 30px rgba(15,82,168,.10);
  --shadow-lg:0 20px 50px rgba(8,28,58,.18);
  --radius:16px;
  --header-h:72px;
}
*{margin:0;padding:0;box-sizing:border-box}
[hidden],.is-hidden{display:none !important}
html{scroll-behavior:smooth;scroll-padding-top:var(--header-h)}
body{
  font-family:"PingFang SC","Microsoft YaHei","Segoe UI",system-ui,-apple-system,"Helvetica Neue",sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
img{display:block;max-width:100%}
a{text-decoration:none;color:inherit}
.container{width:min(1200px,92%);margin:0 auto}
::selection{background:var(--cyan);color:#fff}

/* ---------- 滚动进度 ---------- */
.scroll-progress{position:fixed;top:0;left:0;height:3px;width:0;z-index:1200;
  background:linear-gradient(90deg,var(--bright),var(--cyan));transition:width .1s linear}

/* ---------- 顶部导航 ---------- */
.site-header{position:fixed;top:0;left:0;right:0;z-index:1000;height:var(--header-h);
  display:flex;align-items:center;background:rgba(255,255,255,.72);
  backdrop-filter:blur(14px);border-bottom:1px solid transparent;transition:.3s}
.site-header.scrolled{background:rgba(255,255,255,.94);border-bottom-color:var(--line);box-shadow:0 4px 20px rgba(8,28,58,.06)}
.nav-wrap{display:flex;align-items:center;justify-content:space-between;gap:16px}
.brand{display:flex;align-items:center;gap:10px}
.brand-mark{display:grid;place-items:center;flex:none}
.brand-mark img{height:46px;width:auto;border-radius:10px;box-shadow:0 4px 14px rgba(15,82,168,.22)}
.brand-text{display:flex;flex-direction:column;line-height:1.15}
.brand-text strong{font-size:1.35rem;letter-spacing:2px;color:var(--blue)}
.brand-text small{font-size:.68rem;color:var(--muted);letter-spacing:1px}
.site-nav{display:flex;align-items:center;gap:4px}
.site-nav a{padding:8px 13px;border-radius:10px;font-size:.95rem;color:#2A3C58;font-weight:500;transition:.25s;position:relative}
.site-nav a:hover{color:var(--bright);background:rgba(26,123,224,.08)}
.site-nav a.active{color:var(--bright)}
.site-nav a.active::after{content:"";position:absolute;left:13px;right:13px;bottom:3px;height:2px;border-radius:2px;background:linear-gradient(90deg,var(--bright),var(--cyan))}
.nav-cta{background:linear-gradient(135deg,var(--bright),var(--blue));color:#fff !important;padding:9px 20px !important;box-shadow:0 6px 18px rgba(26,123,224,.35)}
.nav-cta:hover{filter:brightness(1.08);background:linear-gradient(135deg,var(--bright),var(--blue)) !important}
.menu-toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:8px}
.menu-toggle span{width:24px;height:2.5px;border-radius:2px;background:var(--blue);transition:.3s}
.menu-toggle.open span:nth-child(1){transform:translateY(7.5px) rotate(45deg)}
.menu-toggle.open span:nth-child(2){opacity:0}
.menu-toggle.open span:nth-child(3){transform:translateY(-7.5px) rotate(-45deg)}

/* ---------- Hero 轮播 ---------- */
.hero{position:relative}
.carousel{position:relative;height:min(86vh,760px);min-height:520px;overflow:hidden;background:var(--blue-deep)}
.carousel-track,.carousel-slide{position:absolute;inset:0}
.carousel-slide img{width:100%;height:100%;object-fit:cover;opacity:0;transform:scale(1.06);transition:opacity 1s ease,transform 6s ease}
.carousel-slide.is-active img{opacity:1;transform:scale(1)}
.carousel-slide::after{content:none}
.slide-caption{position:relative;z-index:2;height:100%;display:flex;flex-direction:column;justify-content:center;
  color:#fff;max-width:1200px;opacity:0;transform:translateY(26px);transition:.9s ease .35s}
.carousel-slide.is-active .slide-caption{opacity:1;transform:none}
.slide-kicker{color:var(--cyan);font-weight:700;letter-spacing:4px;font-size:.9rem;margin-bottom:14px;text-shadow:0 2px 8px rgba(8,28,58,.65)}
.slide-caption h1{font-size:clamp(1.9rem,4.6vw,3.4rem);line-height:1.25;font-weight:800;text-shadow:0 2px 6px rgba(8,28,58,.65),0 4px 26px rgba(8,28,58,.55);max-width:20ch}
.slide-sub{margin-top:16px;font-size:clamp(.98rem,1.6vw,1.2rem);color:#fff;max-width:44ch;text-shadow:0 2px 8px rgba(8,28,58,.6)}
.slide-actions{margin-top:34px;display:flex;gap:14px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:13px 32px;border-radius:999px;
  font-size:1rem;font-weight:600;cursor:pointer;border:0;transition:.3s}
.btn-primary{background:linear-gradient(135deg,var(--bright),var(--blue));color:#fff;box-shadow:0 10px 26px rgba(26,123,224,.45)}
.btn-primary:hover{transform:translateY(-3px);box-shadow:0 14px 32px rgba(26,123,224,.55)}
.btn-primary:disabled{opacity:.65;cursor:wait;transform:none;box-shadow:0 8px 18px rgba(26,123,224,.28)}
.btn-ghost{background:rgba(255,255,255,.14);color:#fff;border:1.5px solid rgba(255,255,255,.65);backdrop-filter:blur(6px)}
.btn-ghost:hover{background:rgba(255,255,255,.26)}
.carousel-arrow{position:absolute;top:50%;transform:translateY(-50%);z-index:5;width:52px;height:52px;border-radius:50%;
  border:1.5px solid rgba(255,255,255,.4);background:rgba(8,28,58,.35);color:#fff;font-size:1.25rem;cursor:pointer;
  backdrop-filter:blur(6px);transition:.3s;display:grid;place-items:center}
.carousel-arrow:hover{background:var(--bright);border-color:var(--bright)}
.carousel-arrow.prev{left:22px}
.carousel-arrow.next{right:22px}
.carousel-dots{position:absolute;bottom:66px;left:0;right:0;z-index:5;display:flex;justify-content:center;gap:10px}
.carousel-dots button{width:34px;height:4px;border-radius:4px;border:0;background:rgba(255,255,255,.4);cursor:pointer;transition:.35s;padding:0}
.carousel-dots button.is-active{background:var(--cyan);width:52px}
.carousel-progress{position:absolute;bottom:0;left:0;right:0;z-index:5;height:4px;background:rgba(255,255,255,.15)}
.carousel-progress span{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--cyan),var(--bright))}

/* 能力条 */
.factbar{background:#fff;border-bottom:1px solid var(--line);box-shadow:var(--shadow)}
.factbar-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;padding:26px 0}
.fact-item{display:flex;flex-direction:column;align-items:center;text-align:center;gap:2px;
  border-right:1px dashed var(--line);padding:6px 10px}
.fact-item:last-child{border-right:0}
.fact-item b{font-size:1.3rem;color:var(--blue)}
.fact-item span{color:var(--muted);font-size:.88rem}

/* ---------- 通用区块 ---------- */
.section{padding:96px 0}
.section-alt{background:var(--bg-alt)}
.section-dark{background:linear-gradient(150deg,#081C3A 0%,#0F3B7A 55%,#0F52A8 120%);color:#fff}
.section-dark .section-sub{color:rgba(255,255,255,.75)}
.section-head{text-align:center;max-width:720px;margin:0 auto 56px}
.eyebrow{color:var(--bright);font-weight:700;letter-spacing:4px;font-size:.82rem;text-transform:uppercase}
.section-dark .eyebrow{color:var(--cyan)}
.section-head h2{font-size:clamp(1.6rem,3.4vw,2.4rem);margin:8px 0 10px;font-weight:800;color:var(--blue-deep)}
.section-dark .section-head h2{color:#fff}
.section-sub{color:var(--muted);font-size:1.02rem}

/* ---------- 平台简介 ---------- */
.about-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center}
.about-text p{margin-bottom:18px;color:#33465F;font-size:1.02rem}
.about-text strong{color:var(--blue)}
.tag-list{list-style:none;display:flex;flex-wrap:wrap;gap:10px;margin-top:22px}
.tag-list li{padding:7px 18px;border-radius:999px;background:rgba(26,123,224,.09);color:var(--blue);
  font-size:.9rem;font-weight:600;border:1px solid rgba(26,123,224,.18)}
.about-media{display:flex;flex-direction:column;gap:18px}
.about-photo{position:relative;border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow-lg)}
.about-photo img{width:100%;height:100%;object-fit:cover;transition:transform .6s}
.about-photo:hover img{transform:scale(1.05)}
.about-photo figcaption{position:absolute;left:0;right:0;bottom:0;padding:26px 20px 14px;color:#fff;font-size:.92rem;
  background:linear-gradient(180deg,transparent,rgba(8,28,58,.85))}
.about-photo.small{height:240px}

/* ---------- 核心功能 ---------- */
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.feature-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:34px 28px;
  box-shadow:var(--shadow);transition:.35s;position:relative;overflow:hidden}
.feature-card::before{content:"";position:absolute;top:0;left:0;right:0;height:4px;transform:scaleX(0);
  transform-origin:left;background:linear-gradient(90deg,var(--bright),var(--cyan));transition:.4s}
.feature-card:hover{transform:translateY(-8px);box-shadow:0 22px 44px rgba(15,82,168,.16)}
.feature-card:hover::before{transform:scaleX(1)}
.feature-icon{font-size:2.1rem;margin-bottom:16px}
.feature-card h3{font-size:1.16rem;margin-bottom:10px;color:var(--blue-deep)}
.feature-card p{color:var(--muted);font-size:.94rem}

/* 跟踪演示 */
.track-section{padding:28px 0 8px;background:#fff}
.track-demo{margin-top:0;background:#fff;border:1px solid var(--line);border-radius:20px;
  box-shadow:var(--shadow-lg);overflow:hidden}
.track-head{background:linear-gradient(135deg,var(--blue) 0%,var(--bright) 100%);color:#fff;padding:30px 36px 24px}
.track-head h3{font-size:1.3rem;margin-bottom:6px}
.track-head p{color:rgba(255,255,255,.85);font-size:.95rem}
.track-form{display:flex;gap:14px;padding:24px 36px;flex-wrap:wrap}
.track-form input{flex:1;min-width:240px;padding:13px 20px;border-radius:12px;border:1.5px solid var(--line);
  font-size:1rem;outline:none;transition:.25s;background:#FAFCFF}
.track-form input:focus{border-color:var(--bright);box-shadow:0 0 0 4px rgba(26,123,224,.12)}
.track-result{padding:6px 36px 30px}
.track-status{margin:0 36px 18px;padding:12px 16px;border-radius:12px;background:#FFF6F6;color:#C0392B;
  border:1px solid #FADBD8;font-size:.92rem}
.track-status.is-loading{background:#F3F7FC;color:var(--muted);border-color:var(--line)}
.track-order{margin-bottom:20px;padding-bottom:18px;border-bottom:1px solid var(--line)}
.track-state{font-size:1.25rem;color:var(--blue);font-weight:800;margin-bottom:8px}
.track-order-meta{display:flex;flex-wrap:wrap;gap:8px 20px;align-items:center;margin-bottom:12px;color:#33465F;font-size:.95rem}
.track-date{margin-left:auto;color:#98A7BD;font-size:.88rem}
.track-info{display:none}
.track-info-row{display:flex;justify-content:space-between;gap:16px;align-items:flex-start;font-size:.92rem;line-height:1.6}
.track-info-row .label{color:var(--muted);flex:none;padding-right:8px}
.track-info-row .value{color:var(--ink);text-align:right;word-break:break-all;flex:1}
.track-sites{display:inline-flex;align-items:center;flex-wrap:wrap;justify-content:flex-end;gap:6px}
.track-sites .site-arrow{color:#98A7BD}
.track-tools{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:8px;margin-top:14px}
.track-tool{border:1px solid var(--line);background:#fff;color:var(--ink);border-radius:999px;padding:6px 14px;
  font-size:.82rem;cursor:pointer;transition:.2s}
.track-tool:hover{border-color:var(--bright);color:var(--bright)}
.track-sec-title{font-size:.98rem;font-weight:700;color:var(--ink);margin:4px 0 16px;padding-left:10px;border-left:3px solid var(--bright)}
.track-empty{color:#98A7BD;text-align:center;padding:12px 0;font-size:.9rem}
.track-vehicle{display:inline-block;margin-left:8px;font-size:.75rem;border:1px solid var(--line);border-radius:6px;
  padding:1px 6px;color:var(--muted);font-style:normal;cursor:pointer;background:#fff}
.track-steps{list-style:none;position:relative;margin-left:10px}
.track-steps::before{content:"";position:absolute;left:11px;top:8px;bottom:8px;width:2px;background:var(--line)}
.track-steps li{position:relative;display:flex;gap:18px;padding:0 0 22px 34px}
.track-steps li > div{flex:1}
.track-steps li div{display:flex;flex-direction:column}
.track-steps b{font-size:.98rem;color:var(--ink)}
.track-steps span{color:var(--muted);font-size:.88rem}
.track-steps em{font-style:normal;color:#98A7BD;font-size:.8rem}
.track-steps i{position:absolute;left:0;top:4px;width:22px;height:22px;border-radius:50%;
  background:#fff;border:2px solid var(--line)}
.track-steps li.done i{border-color:var(--bright);background:var(--bright);box-shadow:0 0 0 4px rgba(26,123,224,.15)}
.track-steps li.done i::after{content:"✓";position:absolute;inset:0;display:grid;place-items:center;color:#fff;font-size:.72rem;font-weight:800}
.track-steps li.doing i{border-color:var(--cyan);background:#E8F9FF;animation:pulse 1.6s infinite}
@keyframes pulse{0%,100%{box-shadow:0 0 0 0 rgba(53,198,244,.4)}50%{box-shadow:0 0 0 8px rgba(53,198,244,0)}}
.track-steps li.doing b{color:var(--bright)}
.track-preview{position:fixed;inset:0;z-index:1100;background:rgba(8,28,58,.55);display:flex;align-items:center;
  justify-content:center;padding:24px}
.track-preview-box{background:#fff;border-radius:16px;max-width:640px;width:min(640px,100%);max-height:84vh;overflow:auto;
  padding:18px 20px 20px;box-shadow:var(--shadow-lg)}
.track-preview-head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:14px;font-weight:700}
.track-preview-close{border:0;background:none;font-size:22px;line-height:1;color:#666;cursor:pointer}
.track-preview-body img{display:block;width:100%;margin-bottom:10px;border-radius:8px}
.track-preview-body iframe{display:block;width:100%;min-height:70vh;border:0;background:#f5f5f5;border-radius:8px}
.track-preview-empty{text-align:center;color:#98A7BD;padding:24px 0}

/* ---------- 网络生态 marquee ---------- */
.marquee{overflow:hidden;position:relative;padding:6px 0;
  -webkit-mask-image:linear-gradient(90deg,transparent,#000 8%,#000 92%,transparent);
          mask-image:linear-gradient(90deg,transparent,#000 8%,#000 92%,transparent)}
.marquee-track{display:flex;gap:16px;width:max-content;animation:marquee 30s linear infinite}
.marquee:hover .marquee-track{animation-play-state:paused}
.marquee-track span{flex:none;padding:14px 30px;background:#fff;border:1px solid var(--line);border-radius:14px;
  font-weight:700;color:#2A3C58;font-size:1.02rem;box-shadow:var(--shadow)}
@keyframes marquee{to{transform:translateX(-50%)}}
.partners-note{text-align:center;color:var(--muted);font-size:.92rem;margin-top:26px}

/* ---------- 合作模式 ---------- */
.model-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.model-card{background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.16);border-radius:var(--radius);
  padding:30px 26px;backdrop-filter:blur(6px);transition:.35s}
.model-card:hover{background:rgba(53,198,244,.14);transform:translateY(-6px)}
.model-num{font-size:2.2rem;font-weight:800;color:var(--cyan);opacity:.9}
.model-card h3{font-size:1.1rem;margin:10px 0 8px}
.model-card p{color:rgba(255,255,255,.78);font-size:.9rem}
.model-flow{margin-top:52px;display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:12px}
.flow-node{padding:12px 22px;border-radius:999px;background:rgba(255,255,255,.1);border:1px solid rgba(53,198,244,.45);
  font-size:.92rem;font-weight:600}
.flow-arrow{color:var(--cyan);font-size:1.3rem;animation:flowArrow 1.8s infinite}
@keyframes flowArrow{50%{opacity:.35;transform:translateX(4px)}}

/* ---------- 电商 & 优势 ---------- */
.ecom-row{text-align:center;margin-bottom:44px}
.ecom-row > p{color:var(--muted);margin-bottom:16px}
.ecom-chips{display:flex;justify-content:center;flex-wrap:wrap;gap:14px}
.ecom-chips span{padding:10px 28px;border-radius:999px;font-weight:700;color:var(--blue);
  background:#fff;border:1.5px solid rgba(26,123,224,.25);box-shadow:var(--shadow);transition:.3s}
.ecom-chips span:hover{background:var(--bright);color:#fff;transform:translateY(-3px)}
.adv-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px;margin-top:20px}
.adv-card{background:#fff;border-radius:var(--radius);padding:30px 26px;box-shadow:var(--shadow);
  border-top:4px solid transparent;transition:.35s}
.adv-card:hover{border-top-color:var(--cyan);transform:translateY(-6px);box-shadow:0 18px 40px rgba(15,82,168,.15)}
.adv-card h3{font-size:1.05rem;margin-bottom:10px;color:var(--blue-deep)}
.adv-card p{color:var(--muted);font-size:.92rem}

/* ---------- 视频中心 ---------- */
.video-grid{display:grid;grid-template-columns:minmax(0,420px) 1fr;gap:44px;align-items:start}
.video-stage{position:relative;border-radius:22px;overflow:hidden;background:var(--blue-deep);
  box-shadow:var(--shadow-lg);aspect-ratio:9/13;max-height:74vh;margin:0 auto;width:100%}
.video-stage video{width:100%;height:100%;object-fit:contain;background:var(--blue-deep)}
.video-play-btn{position:absolute;inset:0;margin:auto;width:88px;height:88px;border-radius:50%;border:0;cursor:pointer;
  background:rgba(26,123,224,.92);display:grid;place-items:center;box-shadow:0 0 0 10px rgba(26,123,224,.25),0 18px 40px rgba(8,28,58,.4);
  transition:.35s}
.video-play-btn::before{content:"";position:absolute;inset:-10px;border-radius:50%;border:2px solid rgba(53,198,244,.6);animation:ring 2s infinite}
@keyframes ring{0%{transform:scale(.9);opacity:1}100%{transform:scale(1.35);opacity:0}}
.video-play-btn:hover{transform:scale(1.08);background:var(--blue)}
.video-play-btn.hidden{opacity:0;pointer-events:none}
.video-bar{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;
  background:#fff;border:1px solid var(--line);border-radius:14px;padding:14px 20px;margin-top:16px;box-shadow:var(--shadow)}
.video-title{font-weight:700;color:var(--blue-deep)}
.video-hint{color:var(--muted);font-size:.82rem}
.video-playlist h3{font-size:1.1rem;color:var(--blue-deep);margin-bottom:18px}
.video-item{width:100%;display:flex;align-items:center;gap:18px;text-align:left;cursor:pointer;
  background:#fff;border:1.5px solid var(--line);border-radius:16px;padding:20px 22px;transition:.3s;margin-bottom:14px}
.video-item:hover{border-color:var(--bright);transform:translateX(6px)}
.video-item.is-active{border-color:var(--bright);background:linear-gradient(135deg,rgba(26,123,224,.07),rgba(53,198,244,.1))}
.vi-num{flex:none;width:42px;height:42px;border-radius:12px;display:grid;place-items:center;font-weight:800;
  background:var(--bg-alt);color:var(--blue);font-size:1.05rem}
.video-item.is-active .vi-num{background:linear-gradient(135deg,var(--bright),var(--blue));color:#fff}
.vi-body{display:flex;flex-direction:column}
.vi-body b{color:var(--ink);font-size:1rem}
.vi-body small{color:var(--muted);font-size:.85rem}
.video-cta{margin-top:22px;background:linear-gradient(135deg,var(--blue),var(--bright));border-radius:16px;
  padding:26px;color:#fff;display:flex;flex-direction:column;gap:16px;align-items:flex-start}
.video-cta p{font-weight:700}
.video-cta .btn{background:#fff;color:var(--blue);box-shadow:none}

/* ---------- 图片展示 ---------- */
.filter-bar{display:flex;justify-content:center;flex-wrap:wrap;gap:12px;margin-bottom:40px}
.filter-bar button{padding:9px 24px;border-radius:999px;border:1.5px solid var(--line);background:#fff;
  color:#2A3C58;font-size:.92rem;font-weight:600;cursor:pointer;transition:.3s}
.filter-bar button:hover{border-color:var(--bright);color:var(--bright)}
.filter-bar button.is-active{background:linear-gradient(135deg,var(--bright),var(--blue));color:#fff;border-color:transparent;box-shadow:0 8px 20px rgba(26,123,224,.35)}
.gallery-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.gallery-item{position:relative;border-radius:var(--radius);overflow:hidden;cursor:zoom-in;box-shadow:var(--shadow);
  transition:transform .35s, box-shadow .35s, opacity .4s}
.gallery-item img{width:100%;aspect-ratio:16/10;object-fit:cover;transition:transform .6s}
.gallery-item:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg)}
.gallery-item:hover img{transform:scale(1.08)}
.gallery-item figcaption{position:absolute;left:0;right:0;bottom:0;padding:34px 18px 13px;color:#fff;font-size:.9rem;
  background:linear-gradient(180deg,transparent,rgba(8,28,58,.85));opacity:0;transform:translateY(8px);transition:.35s}
.gallery-item:hover figcaption{opacity:1;transform:none}
.gallery-item.hide{display:none}
.gallery-hint{text-align:center;color:#98A7BD;font-size:.88rem;margin-top:34px}

/* ---------- 入驻 CTA ---------- */
.cta-section{background:linear-gradient(180deg,var(--bg) 0%,#EAF3FD 100%)}
.cta-box{background:linear-gradient(140deg,#081C3A 0%,#0F3B7A 60%,#0F52A8 115%);border-radius:26px;
  padding:clamp(36px,6vw,64px);color:#fff;box-shadow:var(--shadow-lg);display:grid;grid-template-columns:1.2fr .8fr;gap:36px;align-items:center}
.cta-text h2{font-size:clamp(1.5rem,3vw,2.1rem);line-height:1.35;margin:10px 0 14px}
.cta-text p{color:rgba(255,255,255,.82)}
.cta-cards{display:flex;flex-direction:column;gap:12px}
.cta-card{background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.16);border-radius:14px;
  padding:16px 20px;display:flex;flex-direction:column;gap:2px;transition:.3s}
.cta-card:hover{background:rgba(53,198,244,.15)}
.cta-card b{font-size:1rem}
.cta-card span{color:rgba(255,255,255,.75);font-size:.86rem}
.contact-info{grid-column:1/-1;display:flex;flex-wrap:wrap;gap:10px 34px;padding-top:22px;
  border-top:1px dashed rgba(255,255,255,.25);font-size:.95rem;color:rgba(255,255,255,.9)}
.contact-info i{font-style:normal;color:var(--cyan)}

/* ---------- 页脚 ---------- */
.site-footer{background:var(--blue-deep);color:rgba(255,255,255,.85)}
.footer-grid{display:flex;justify-content:space-between;align-items:center;gap:24px;padding:44px 0;flex-wrap:wrap}
.footer-brand{display:flex;align-items:center;gap:14px}
.footer-brand b{font-size:1.25rem;color:#fff;letter-spacing:2px}
.footer-brand p{font-size:.85rem;margin-top:2px}
.footer-nav{display:flex;gap:22px;flex-wrap:wrap}
.footer-nav a{font-size:.9rem;opacity:.8;transition:.25s}
.footer-nav a:hover{opacity:1;color:var(--cyan)}
.footer-bottom{border-top:1px solid rgba(255,255,255,.12);padding:18px 0;text-align:center;font-size:.84rem;color:rgba(255,255,255,.6)}
.footer-bottom p+p{margin-top:6px}
.footer-bottom i{font-style:normal;color:rgba(255,255,255,.4)}
.footer-bottom a{color:rgba(255,255,255,.85);border-bottom:1px solid rgba(53,198,244,.45);transition:.25s}
.footer-bottom a:hover{color:var(--cyan);border-bottom-color:var(--cyan)}

/* ---------- 返回顶部 ---------- */
.back-top{position:fixed;right:26px;bottom:26px;z-index:900;width:50px;height:50px;border-radius:50%;border:0;cursor:pointer;
  background:linear-gradient(135deg,var(--bright),var(--blue));color:#fff;font-size:1.25rem;
  box-shadow:0 10px 26px rgba(26,123,224,.45);opacity:0;pointer-events:none;transform:translateY(14px);transition:.35s}
.back-top.show{opacity:1;pointer-events:auto;transform:none}
.back-top:hover{filter:brightness(1.12)}

/* ---------- 灯箱 ---------- */
.lightbox{position:fixed;inset:0;z-index:2000;background:rgba(6,16,34,.92);backdrop-filter:blur(8px);
  display:grid;place-items:center;opacity:0;pointer-events:none;transition:.35s}
.lightbox.open{opacity:1;pointer-events:auto}
.lb-figure{max-width:min(92vw,1200px);max-height:88vh;display:flex;flex-direction:column;gap:12px}
.lb-figure img{max-width:100%;max-height:80vh;object-fit:contain;border-radius:10px;box-shadow:0 30px 80px rgba(0,0,0,.6)}
.lb-figure figcaption{text-align:center;color:rgba(255,255,255,.85);font-size:.95rem}
.lb-close{position:absolute;top:22px;right:26px;width:46px;height:46px;border-radius:50%;border:1px solid rgba(255,255,255,.35);
  background:rgba(255,255,255,.1);color:#fff;font-size:1.05rem;cursor:pointer;transition:.3s}
.lb-close:hover{background:var(--bright)}
.lb-arrow{position:absolute;top:50%;transform:translateY(-50%);width:54px;height:54px;border-radius:50%;
  border:1px solid rgba(255,255,255,.35);background:rgba(255,255,255,.1);color:#fff;font-size:1.2rem;cursor:pointer;transition:.3s}
.lb-arrow:hover{background:var(--bright)}
.lb-arrow.prev{left:24px}
.lb-arrow.next{right:24px}

/* ---------- 滚动渐显 ---------- */
.reveal{opacity:0;transform:translateY(34px);transition:opacity .8s ease var(--d,0s),transform .8s ease var(--d,0s)}
.reveal.in{opacity:1;transform:none}

/* ---------- 响应式 ---------- */
@media (max-width:1024px){
  .feature-grid{grid-template-columns:repeat(2,1fr)}
  .model-grid,.adv-grid{grid-template-columns:repeat(2,1fr)}
  .factbar-grid{grid-template-columns:repeat(2,1fr)}
  .fact-item:nth-child(2){border-right:0}
  .gallery-grid{grid-template-columns:repeat(2,1fr)}
  .video-grid{grid-template-columns:1fr;gap:30px}
  .video-stage{max-width:440px}
  .cta-box{grid-template-columns:1fr}
  .about-grid{grid-template-columns:1fr;gap:34px}
}
@media (max-width:760px){
  :root{--header-h:62px}
  .brand-mark img{height:38px}
  .brand-text strong{font-size:1.15rem}
  .brand-text small{font-size:.6rem}
  .section{padding:70px 0}
  .site-nav{position:fixed;top:var(--header-h);left:0;right:0;flex-direction:column;align-items:stretch;
    background:#fff;padding:14px 6%;gap:4px;border-bottom:1px solid var(--line);box-shadow:0 24px 40px rgba(8,28,58,.12);
    transform:translateY(-130%);transition:transform .4s ease;opacity:0;pointer-events:none}
  .site-nav.open{transform:none;opacity:1;pointer-events:auto}
  .site-nav a{padding:13px 14px;border-radius:10px}
  .menu-toggle{display:flex}
  .carousel{min-height:460px;height:64vh}
  .carousel-arrow{width:42px;height:42px}
  .carousel-arrow.prev{left:10px}
  .carousel-arrow.next{right:10px}
  .carousel-dots{bottom:54px}
  .feature-grid,.model-grid,.adv-grid,.gallery-grid,.factbar-grid{grid-template-columns:1fr}
  .fact-item{border-right:0;border-bottom:1px dashed var(--line);padding:10px 0}
  .fact-item:last-child{border-bottom:0}
  .track-form,.track-head,.track-result{padding-left:20px;padding-right:20px}
  .track-status{margin-left:20px;margin-right:20px}
  .track-date{margin-left:0}
  .lb-arrow{width:44px;height:44px}
  .lb-arrow.prev{left:8px}
  .lb-arrow.next{right:8px}
  .model-flow{gap:8px}
  .flow-arrow{display:none}
  .flow-node{width:100%;text-align:center}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.001s !important;transition-duration:.001s !important}
  html{scroll-behavior:auto}
  .reveal{opacity:1;transform:none}
}