/* ==========================================================================
   鼎笙伯格官网 · 首页样式
   基调：简洁浅色 / 白与浅灰底 + 藏青标题 + 金色点缀（与 logo 统一）
   ========================================================================== */

:root{
  --navy-900:#0a1f3d;
  --navy:#10305c;
  --navy-600:#1c4478;
  --ink:#243447;
  --text:#55637a;
  --muted:#8a97ab;
  --gold:#b8892b;
  --gold-600:#a2761f;
  --line:#e4e9f1;
  --line-2:#eef2f7;
  --bg-soft:#f6f8fb;
  --bg-warm:#fbfaf6;
  --white:#fff;
  --shadow-sm:0 2px 10px rgba(16,48,92,.06);
  --shadow-md:0 12px 32px rgba(16,48,92,.10);
  --shadow-lg:0 22px 54px rgba(16,48,92,.14);
  --radius:10px;
  --radius-sm:6px;
  --container:1240px;
  --font-sans:"PingFang SC","Microsoft YaHei","Hiragino Sans GB","Source Han Sans SC","Noto Sans CJK SC",system-ui,-apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --font-serif:Georgia,"Times New Roman","Songti SC","Source Han Serif SC",serif;
  --header-h:78px;
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.85;
  color:var(--text);
  background:var(--white);
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
ul,ol{margin:0;padding:0;list-style:none}
h1,h2,h3,h4{margin:0;color:var(--navy);font-weight:700;line-height:1.4;letter-spacing:.5px}
p{margin:0 0 1em}
.serif{font-family:var(--font-serif)}
.container{width:100%;max-width:var(--container);margin:0 auto;padding:0 28px}

/* ---------- 通用小组件 ---------- */
.eyebrow{
  display:flex;align-items:center;gap:10px;
  font-size:13px;letter-spacing:2px;color:var(--gold-600);
  margin:0 0 14px;font-weight:600;
}
.eyebrow-line{width:26px;height:1px;background:var(--gold);display:inline-block;flex:none}
.eyebrow-light{color:#e6c98a}
.eyebrow-light .eyebrow-line{background:#e6c98a}
.section-head .eyebrow{justify-content:center}

section[id]{scroll-margin-top:calc(var(--header-h) + 18px)}
.section{padding:100px 0}
.section-head{max-width:720px;margin:0 auto 54px;text-align:center}
.section-title{font-size:34px;color:var(--navy);margin-bottom:14px;text-wrap:balance}
.section-title.left{text-align:left;margin-bottom:22px}
.section-title.light{color:#fff}
.section-desc{font-size:16px;color:var(--text);margin:0;text-wrap:balance}

/* 品牌标志裁切：logo.png 为 800×800，墨迹实际范围 x 26–782 / y 248–565 */
.logo-crop{
  --lh:var(--logo-h,44px);
  display:inline-block;flex:none;
  width:calc(var(--lh)*2.384);height:var(--lh);
  background-image:url("../img/logo.png");
  background-repeat:no-repeat;
  background-size:calc(var(--lh)*2.5227) calc(var(--lh)*2.5227);
  background-position:calc(var(--lh)*-0.082) calc(var(--lh)*-0.782);
}

.btn{
  display:inline-block;padding:14px 30px;border-radius:var(--radius-sm);
  font-size:15px;font-weight:600;letter-spacing:.6px;line-height:1.2;
  border:1px solid transparent;cursor:pointer;font-family:inherit;
  transition:background-color .22s,color .22s,border-color .22s,transform .22s,box-shadow .22s;
}
.btn:hover{transform:translateY(-2px)}
.btn-lg{padding:17px 38px;font-size:16px}
.btn-primary{background:var(--navy);color:#fff}
.btn-primary:hover{background:var(--navy-900);box-shadow:var(--shadow-md)}
.btn-gold{background:var(--gold);color:#fff}
.btn-gold:hover{background:var(--gold-600);box-shadow:0 12px 28px rgba(184,137,43,.28)}
.btn-ghost{background:rgba(255,255,255,.7);color:var(--navy);border-color:#cfd9e6}
.btn-ghost:hover{border-color:var(--navy);background:#fff}
.btn-sm{padding:10px 20px;font-size:14px}
.btn-block{display:block;width:100%;text-align:center}

/* ---------- 图片占位框 ---------- */
.ph{
  position:relative;margin:0;
  aspect-ratio:var(--ar,4/3);
  display:grid;place-items:center;text-align:center;
  border:1px dashed #c4d2e4;border-radius:14px;
  background:
    repeating-linear-gradient(135deg,rgba(16,48,92,.028) 0 12px,transparent 12px 24px),
    linear-gradient(160deg,#f2f6fb,#fbfcfe);
  color:var(--muted);
  overflow:hidden;
}
.ph-label{padding:16px 20px;line-height:1.7}
.ph-code{display:inline-block;margin-bottom:8px;padding:3px 11px;border-radius:20px;background:var(--navy);color:#fff;font-size:11.5px;font-weight:700;letter-spacing:1.3px}
.ph-name{display:block;font-style:normal;font-size:11.5px;color:#a9bacf;margin-top:6px;letter-spacing:.3px}
.ph-label b{display:block;font-size:14.5px;color:var(--navy-600);font-weight:600;letter-spacing:.5px}
.ph-label small{display:block;font-size:12.5px;color:var(--muted);margin-top:4px}
.ph-ico{display:block;margin:0 auto 10px;width:40px;height:40px;border-radius:50%;background:#fff;box-shadow:var(--shadow-sm);display:grid;place-items:center}
.ph-ico svg{width:22px;height:22px;fill:none;stroke:#a9bacf;stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}
/* 卡片内的小尺寸占位图（正方形 400×400） */
.ph-in{aspect-ratio:1/1;border:0;border-radius:12px;margin-bottom:20px}
.ph-in .ph-label b{font-size:13px}
.ph-in .ph-code{font-size:10.5px;padding:2px 9px;margin-bottom:6px;letter-spacing:1px}
.ph-in .ph-label small{font-size:11.5px;margin-top:2px}
.ph-in::after{content:"";position:absolute;inset:0;border:1px dashed #c4d2e4;border-radius:12px}

/* ---------- 实际配图（替换占位图后） ---------- */
.hero-ph-img{margin:0;border-radius:14px;overflow:hidden;box-shadow:var(--shadow-md)}
.hero-ph-img img{width:100%;height:100%;object-fit:cover;display:block;aspect-ratio:5/4}
.about-img{margin:0;border-radius:14px;overflow:hidden;box-shadow:var(--shadow-md)}
.about-img img{width:100%;height:100%;object-fit:cover;display:block;aspect-ratio:4/3}
.biz-img{margin:0 0 20px;border-radius:12px;overflow:hidden;aspect-ratio:1/1;background:var(--bg-soft)}
.biz-img img{width:100%;height:100%;object-fit:cover;display:block;transition:transform .4s ease}
.biz-card:hover .biz-img img{transform:scale(1.05)}
.band-img{margin:0;line-height:0;overflow:hidden}
.band-img img{width:100%;display:block;object-fit:cover;aspect-ratio:1600/520}

/* ---------- 顶部导航 ---------- */
.site-header{
  position:fixed;top:0;left:0;right:0;z-index:100;
  background:rgba(255,255,255,.94);
  border-bottom:1px solid var(--line-2);
  backdrop-filter:saturate(160%) blur(10px);
  transition:box-shadow .25s,border-color .25s;
}
.site-header.is-stuck{box-shadow:0 4px 20px rgba(16,48,92,.08);border-color:transparent}
.header-inner{height:var(--header-h);display:flex;align-items:center;gap:26px}
.brand{flex:none;display:flex;align-items:center}
.main-nav{display:flex;align-items:center;gap:30px;margin-left:auto}
.main-nav a{position:relative;font-size:15px;color:var(--ink);font-weight:500;padding:6px 0;transition:color .2s}
.main-nav a::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:2px;background:var(--gold);
  transform:scaleX(0);transform-origin:left;transition:transform .25s;
}
.main-nav a:hover{color:var(--navy)}
.main-nav a:hover::after{transform:scaleX(1)}
.header-cta{flex:none}
.nav-toggle{display:none;width:42px;height:38px;border:1px solid var(--line);border-radius:var(--radius-sm);background:#fff;padding:0;cursor:pointer;flex-direction:column;justify-content:center;align-items:center;gap:5px}
.nav-toggle span{display:block;width:18px;height:2px;background:var(--navy);transition:transform .25s,opacity .2s}
.nav-toggle[aria-expanded="true"] span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] span:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* ==========================================================================
   第1屏 · 首屏 Banner
   ========================================================================== */
.hero{
  position:relative;
  min-height:clamp(660px,92vh,900px);
  display:flex;align-items:center;
  padding:calc(var(--header-h) + 70px) 0 80px;
  background:linear-gradient(165deg,#eaf1fa 0%,#f6fafd 46%,#fff 100%);
  overflow:hidden;
}
.hero-bg{position:absolute;inset:0;color:var(--navy);pointer-events:none}
.hero-lines{width:100%;height:100%}
.hero-inner{
  position:relative;
  display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);
  gap:70px;align-items:center;
}
.hero-copy .eyebrow{margin-bottom:22px}
.hero-title{font-size:48px;line-height:1.42;letter-spacing:1.5px;color:var(--navy)}
.hero-title em{font-style:normal;color:var(--gold);margin-right:.12em}
.hero-sub{font-size:17px;color:var(--text);margin:26px 0 40px;letter-spacing:.6px;line-height:1.9}
.hero-actions{display:flex;flex-direction:column;align-items:flex-start;gap:22px}
.hero-links{display:flex;flex-wrap:wrap;gap:12px 30px}
.hero-links a{
  font-size:14.5px;font-weight:600;color:var(--navy-600);letter-spacing:.4px;
  border-bottom:1px solid #cdd9e7;padding-bottom:3px;transition:color .2s,border-color .2s;
}
.hero-links a i{font-style:normal;display:inline-block;transition:transform .22s}
.hero-links a:hover{color:var(--gold-600);border-color:var(--gold)}
.hero-links a:hover i{transform:translateX(4px)}
.hero-ph{--ar:5/4;box-shadow:var(--shadow-md)}

/* ==========================================================================
   第2屏 · 关键数据
   ========================================================================== */
.figures{background:#fff;padding:74px 0 66px;border-bottom:1px solid var(--line-2)}
.figures-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:20px}
.fig{position:relative;padding:6px 26px;text-align:center}
.fig+.fig::before{content:"";position:absolute;left:0;top:14%;bottom:14%;width:1px;background:var(--line)}
.fig-num{display:flex;align-items:baseline;justify-content:center;gap:3px;color:var(--navy);line-height:1}
.fig-num .serif{font-size:52px;font-weight:700;letter-spacing:0}
.fig-num small{font-size:16px;font-weight:600;color:var(--gold-600);letter-spacing:1px}
.fig p{margin:12px 0 0;font-size:13.5px;line-height:1.75;color:var(--muted)}
.figures-net{display:flex;flex-wrap:wrap;justify-content:center;gap:10px 34px;margin:44px 0 0;font-size:13px;letter-spacing:1px;color:var(--navy-600)}
.figures-net span{position:relative;padding-left:15px}
.figures-net span::before{content:"";position:absolute;left:0;top:50%;width:5px;height:5px;margin-top:-2.5px;border-radius:50%;background:var(--gold)}

/* ==========================================================================
   第3屏 · 五大服务入口
   ========================================================================== */
.services{background:var(--bg-soft)}
.service-grid{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:20px}
.service-card{
  display:flex;flex-direction:column;
  background:#fff;border:1px solid var(--line);border-radius:12px;
  padding:28px 24px 26px;position:relative;overflow:hidden;
  transition:transform .28s,box-shadow .28s,border-color .28s;
}
.service-card::after{content:"";position:absolute;left:0;right:0;top:0;height:3px;background:var(--gold);transform:scaleX(0);transform-origin:left;transition:transform .3s}
.service-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-md);border-color:#d7e0ec}
.service-card:hover::after{transform:scaleX(1)}
.sc-top{margin-bottom:18px}
.sc-icon{width:48px;height:48px;border-radius:50%;background:var(--bg-soft);display:grid;place-items:center;transition:background-color .28s}
.sc-icon svg{width:25px;height:25px;fill:none;stroke:var(--navy);stroke-width:2;stroke-linecap:round;stroke-linejoin:round;transition:stroke .28s}
.service-card:hover .sc-icon{background:var(--navy)}
.service-card:hover .sc-icon svg{stroke:#fff}
.service-card h3{font-size:17.5px;margin-bottom:10px;line-height:1.5}
.sc-text{font-size:13.5px;line-height:1.8;color:var(--text);margin:0 0 20px;flex:1}
.sc-more{font-size:13.5px;font-weight:600;color:var(--navy);display:flex;align-items:center;gap:6px}
.sc-more i{font-style:normal;transition:transform .25s}
.service-card:hover .sc-more i{transform:translateX(4px)}

/* ==========================================================================
   第4屏 · 品牌简介
   ========================================================================== */
.about{background:#fff}
.about-grid{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(0,.85fr);gap:70px;align-items:center}
.about-body .section-title{font-size:30px}
.about-body .lead{font-size:17.5px;line-height:1.95;color:var(--ink)}
.about-body p{margin-bottom:20px}
.about-points{margin:0 0 26px}
.about-points li{position:relative;padding:7px 0 7px 26px;font-size:14.5px;color:var(--text)}
.about-points li::before{
  content:"";position:absolute;left:0;top:16px;width:12px;height:2px;background:var(--gold);
}
.about-mark{font-family:var(--font-serif);font-size:52px;color:#dbe4f0;letter-spacing:-1px;line-height:1;user-select:none}

/* ==========================================================================
   第5屏 · 六大业务板块（3 列可折叠卡片）
   ========================================================================== */
.business{background:var(--bg-soft)}
.biz-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px;align-items:start}
.biz-card{
  position:relative;background:#fff;border:1px solid var(--line);border-radius:14px;
  padding:24px 24px 22px;display:flex;flex-direction:column;
  transition:box-shadow .28s,border-color .28s;
}
.biz-card:hover{box-shadow:var(--shadow-md);border-color:#d7e0ec}
.biz-head{display:flex;align-items:center;gap:12px;margin-bottom:10px}
.biz-no{font-size:26px;color:#c9d4e2;font-weight:700;line-height:1}
.biz-card h3{font-size:19px;line-height:1.5}
.biz-note{font-size:14px;line-height:1.8;color:var(--text);margin:0 0 18px;flex:1}
.biz-more{
  display:flex;align-items:center;justify-content:space-between;gap:10px;
  padding-top:12px;border-top:1px solid var(--line-2);
  font-size:14px;font-weight:600;color:var(--navy);letter-spacing:.5px;
}
.biz-more i{font-style:normal;transition:transform .25s,color .25s;color:var(--gold)}
.biz-card:hover .biz-more{color:var(--gold-600)}
.biz-card:hover .biz-more i{transform:translateX(4px)}
.biz-highlight{background:linear-gradient(180deg,#fffdf8,#fff);border-color:#e8d7ae}
.biz-badge{
  position:absolute;top:16px;right:16px;z-index:2;
  background:var(--gold);color:#fff;font-size:11.5px;letter-spacing:1px;
  padding:4px 11px;border-radius:20px;font-weight:600;
}

/* ==========================================================================
   第6屏 · 核心优势
   ========================================================================== */
.advantage{background:#fff;padding-bottom:64px}
.adv-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:22px}
.adv-item{
  background:#fff;border:1px solid var(--line);border-radius:12px;padding:26px 24px;
  transition:transform .26s,box-shadow .26s,border-color .26s;
}
.adv-item:hover{transform:translateY(-4px);box-shadow:var(--shadow-sm);border-color:#d7e0ec}
.adv-no{display:inline-block;font-size:28px;color:var(--gold);font-weight:700;line-height:1;margin-bottom:10px;position:relative;padding-bottom:10px}
.adv-no::after{content:"";position:absolute;left:0;bottom:0;width:26px;height:2px;background:var(--navy)}
.adv-item h3{font-size:16.5px;margin-bottom:9px}
.adv-item p{font-size:13.5px;line-height:1.85;margin:0}
.adv-quote{
  background:linear-gradient(160deg,#0f2b52,#0a1f3d);border-color:transparent;
  display:flex;flex-direction:column;justify-content:center;
}
.adv-quote:hover{border-color:transparent}
.adv-quote h3{color:#e6c98a;font-size:16.5px;margin-bottom:10px}
.adv-quote p{color:#cfdae8;font-size:13.5px;margin:0}
.adv-quote b{color:#fff}

/* ---------- 通栏配图位 ---------- */
.band{background:var(--bg-soft);padding:0 0 0}
.band .ph{border-radius:0;border-left:0;border-right:0}

/* ==========================================================================
   第7屏 · 发展历程
   ========================================================================== */
.history{background:#fff;padding-top:64px}
.timeline{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:26px;position:relative}
.timeline::before{content:"";position:absolute;top:5px;left:6px;right:6px;height:1px;background:var(--line)}
.timeline li{position:relative;padding-top:34px}
.timeline li::before{content:"";position:absolute;top:0;left:0;width:11px;height:11px;border-radius:50%;background:#fff;border:2px solid var(--gold)}
.tl-year{display:block;font-size:28px;color:var(--navy);font-weight:700;line-height:1.2;margin-bottom:12px}
.timeline li p{font-size:14px;line-height:1.8;color:var(--text);margin:0;padding-top:14px;border-top:1px solid var(--line-2)}

/* ==========================================================================
   第8屏 · 联系我们
   ========================================================================== */
.contact{
  background:
    radial-gradient(1000px 460px at 88% -10%,rgba(184,137,43,.22),transparent 60%),
    linear-gradient(135deg,#0d2749 0%,#10305c 55%,#0a1f3d 100%);
  color:#c9d6e6;
}
.contact-grid{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);gap:64px;align-items:start}
.contact-info .section-title{margin-bottom:26px}
.info-list{margin:0}
.info-list>div{display:flex;gap:18px;padding:15px 0;border-bottom:1px solid rgba(255,255,255,.12)}
.info-list dt{flex:none;width:112px;font-size:14px;color:#8fa6c2;letter-spacing:.5px}
.info-list dd{margin:0;font-size:15px;color:#eaf1f8}
.info-list a:hover{color:var(--gold)}

.contact-card{background:#fff;border-radius:14px;padding:34px 32px;box-shadow:var(--shadow-lg)}
.contact-card h3{font-size:22px;margin-bottom:8px}
.cc-sub{font-size:14px;color:var(--text);margin:0 0 24px}
.cc-form{display:grid;gap:16px}
.cc-form label{display:block;font-size:13.5px;font-weight:600;color:var(--navy);letter-spacing:.5px}
.cc-form select,.cc-form input{
  width:100%;margin-top:8px;padding:13px 14px;font-size:15px;font-family:inherit;color:var(--ink);
  background:var(--bg-soft);border:1px solid var(--line);border-radius:var(--radius-sm);
  transition:border-color .2s,background-color .2s,box-shadow .2s;
}
.cc-form select:focus,.cc-form input:focus{outline:none;background:#fff;border-color:var(--navy);box-shadow:0 0 0 3px rgba(16,48,92,.08)}
.cc-form .btn{margin-top:6px}
.cc-tip{font-size:12.5px;color:var(--muted);margin:0;text-align:center}
.cc-alt{margin-top:20px;padding-top:20px;border-top:1px dashed var(--line);text-align:center}

/* ==========================================================================
   第9屏 · 页脚
   ========================================================================== */
.site-footer{background:var(--bg-soft);border-top:1px solid var(--line);padding:70px 0 30px}
.footer-top{display:grid;grid-template-columns:minmax(0,.95fr) minmax(0,2fr);gap:56px;padding-bottom:44px;border-bottom:1px solid var(--line)}
.footer-logo{margin-bottom:20px}
.footer-brand p{font-size:14px;color:var(--text);margin-bottom:10px}
.fb-contact{font-size:13.5px;color:var(--muted);line-height:1.9}
.fb-contact a:hover{color:var(--navy)}
.footer-nav{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:32px}
.footer-nav h4{font-size:15px;color:var(--navy);margin-bottom:16px;letter-spacing:1px}
.footer-nav a{display:block;font-size:13.5px;color:var(--text);padding:5px 0;transition:color .2s,padding-left .2s}
.footer-nav a:hover{color:var(--gold-600);padding-left:4px}

.qr-matrix{padding:44px 0 8px;border-bottom:1px solid var(--line)}
.qr-title{font-size:17px;text-align:center;margin-bottom:30px;letter-spacing:1px}
.qr-primary{display:flex;justify-content:center;gap:34px;margin-bottom:32px}
.qr-secondary{display:flex;justify-content:center;flex-wrap:wrap;gap:26px}
.qr{margin:0;text-align:center}
.qr-box{background:#fff;border:1px solid var(--line);border-radius:10px;padding:8px;box-shadow:var(--shadow-sm);transition:transform .25s,box-shadow .25s}
.qr-box img{width:100%;border-radius:4px}
.qr-main .qr-box{width:158px;height:158px;padding:10px}
.qr-secondary .qr-box{width:104px;height:104px}
.qr:hover .qr-box{transform:translateY(-4px);box-shadow:var(--shadow-md)}
.qr figcaption{margin-top:12px;line-height:1.5}
.qr figcaption b{display:block;font-size:14px;color:var(--navy);font-weight:600}
.qr figcaption span{font-size:12px;color:var(--muted)}
.qr-code{display:block;font-style:normal;font-size:11px;color:#a9bacf;letter-spacing:1px;margin-top:3px}
.qr-main figcaption b{font-size:15px}
.qr-note{text-align:center;font-size:12px;color:var(--muted);margin:26px 0 0}

.footer-bottom{padding-top:26px;text-align:center}
.compliance{font-size:12.5px;line-height:1.9;color:var(--muted);max-width:940px;margin:0 auto 16px;text-align:justify}
.compliance b{color:var(--navy)}
.copyright{font-size:12.5px;color:var(--muted);margin:0}
.copyright a{color:var(--muted)}
.copyright a:hover{color:var(--navy)}

/* ---------- 客服微信浮窗 / 返回顶部 ---------- */
.wx-float{position:fixed;right:22px;bottom:26px;z-index:120}
.wx-btn{
  display:flex;align-items:center;gap:8px;padding:12px 18px;border:none;border-radius:30px;cursor:pointer;
  background:var(--navy);color:#fff;font-family:inherit;font-size:14px;font-weight:600;letter-spacing:.5px;
  box-shadow:var(--shadow-md);transition:background-color .25s,transform .25s;
}
.wx-btn:hover{background:var(--navy-900);transform:translateY(-2px)}
.wx-btn svg{width:20px;height:20px;fill:#fff}
.wx-panel{
  position:absolute;right:0;bottom:calc(100% + 12px);width:196px;background:#fff;
  border:1px solid var(--line);border-radius:12px;box-shadow:var(--shadow-lg);padding:14px;text-align:center;
  animation:pop .22s ease-out;
}
@keyframes pop{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}
.wx-panel img{width:100%;border-radius:6px}
.wx-panel p{margin:10px 0 0;font-size:12.5px;line-height:1.7;color:var(--text)}

.back-top{
  position:fixed;left:22px;bottom:26px;width:44px;height:44px;border-radius:50%;
  background:#fff;border:1px solid var(--line);color:var(--navy);
  display:grid;place-items:center;font-size:18px;box-shadow:var(--shadow-sm);
  opacity:0;visibility:hidden;transition:opacity .25s,transform .25s,visibility .25s;z-index:120;
}
.back-top.show{opacity:1;visibility:visible}
.back-top:hover{transform:translateY(-3px);border-color:var(--gold);color:var(--gold-600)}

/* ---------- 进场动画 ---------- */
.reveal{opacity:0;transform:translateY(22px);transition:opacity .6s ease-out,transform .6s ease-out}
.reveal.in{opacity:1;transform:none}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal{opacity:1;transform:none;transition:none}
}

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width:1200px){
  .main-nav{gap:22px}
  .hero-title{font-size:42px}
  .hero-inner{gap:44px}
  .service-grid{grid-template-columns:repeat(3,minmax(0,1fr))}
  .biz-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .adv-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
}

@media (max-width:1024px){
  .header-cta{display:none}
  .section{padding:80px 0}
  .hero{min-height:0;padding:calc(var(--header-h) + 60px) 0 70px}
  .hero-inner{grid-template-columns:1fr;gap:40px}
  .hero-ph{max-width:560px}
  .about-grid{grid-template-columns:1fr;gap:36px}
  .about-mark{margin-top:18px;font-size:44px}
  .contact-grid{grid-template-columns:1fr;gap:40px}
  .footer-top{grid-template-columns:1fr;gap:36px}
  .figures-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:32px 12px}
  .fig+.fig::before{display:none}
  .timeline{grid-template-columns:repeat(2,minmax(0,1fr));gap:30px 26px}
  .timeline::before{display:none}
  .tl-year{margin-bottom:10px}
}

@media (max-width:860px){
  .nav-toggle{display:flex;margin-left:auto}
  .main-nav{
    position:fixed;top:var(--header-h);left:0;right:0;
    flex-direction:column;align-items:stretch;gap:0;
    background:#fff;border-bottom:1px solid var(--line);box-shadow:var(--shadow-md);
    max-height:0;overflow:hidden;transition:max-height .32s ease-out;
  }
  .main-nav.open{max-height:70vh;overflow:auto}
  .main-nav a{padding:15px 28px;border-top:1px solid var(--line-2);font-size:15.5px}
  .main-nav a::after{display:none}
  .section-title{font-size:28px}
  .hero-title{font-size:34px;line-height:1.5}
  .hero-sub{font-size:16px;margin:22px 0 32px}
  .biz-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-nav{grid-template-columns:repeat(2,minmax(0,1fr))}
}

@media (max-width:640px){
  :root{--header-h:66px}
  .container{padding:0 20px}
  .brand{--logo-h:36px}
  .section{padding:60px 0}
  .section-head{margin-bottom:36px}
  .eyebrow{font-size:12px;letter-spacing:.8px;gap:8px}
  .eyebrow-line{width:18px}
  .hero{padding:calc(var(--header-h) + 44px) 0 50px}
  .hero-title{font-size:27px;letter-spacing:.8px}
  .hero-sub{font-size:15px;line-height:1.85}
  .hero-actions .btn{width:100%;text-align:center}
  .hero-links{width:100%;gap:10px 22px}
  .hero-links a{font-size:14px}
  .figures{padding:52px 0 46px}
  .figures-grid{grid-template-columns:1fr 1fr;gap:26px 8px}
  .fig{padding:4px 6px}
  .fig-num .serif{font-size:38px}
  .figures-net{gap:8px 20px;font-size:12px;margin-top:32px}
  .service-grid{grid-template-columns:1fr}
  .biz-grid{grid-template-columns:1fr}
  .adv-grid{grid-template-columns:1fr}
  .section-title{font-size:25px}
  .timeline{grid-template-columns:1fr;gap:0}
  .timeline li{padding-left:26px;border-left:1px solid var(--line);padding-bottom:26px;padding-top:0}
  .timeline li::before{top:4px;left:-6px}
  .tl-year{margin-bottom:10px;font-size:24px}
  .timeline li p{padding-top:0;border-top:none}
  .contact-card{padding:26px 20px}
  .info-list dt{width:88px;font-size:13px}
  .info-list dd{font-size:14px}
  .qr-primary{flex-direction:column;align-items:center;gap:22px}
  .qr-secondary{gap:18px}
  .qr-main .qr-box{width:140px;height:140px}
  .qr-secondary .qr-box{width:92px;height:92px}
  .footer-nav{grid-template-columns:1fr}
  .wx-btn span{display:none}
  .wx-btn{padding:14px}
  .back-top{left:auto;right:22px;bottom:88px}
  .compliance{text-align:left}
}