/* ============================================================
   汇食科技 · 官网共享样式  site.css
   Apple 风格设计系统 — 6 个页面统一引用
   ============================================================ */

/* ============ DESIGN TOKENS ============ */
:root{
  --bg:#fff; --bg-soft:#f5f5f7; --bg-dark:#000; --bg-dark-2:#1d1d1f; --bg-dark-3:#0a0a0a;
  --text:#1d1d1f; --text-soft:#6e6e73; --text-inv:#f5f5f7; --text-inv-soft:#a1a1a6;
  --accent:#2d7a5f;            /* 品牌墨绿（呼应 LOGO） */
  --accent-hi:#5ba884;         /* 嫩绿高光 */
  --accent-2:#0a84ff;          /* 科技蓝 */
  --leaf:#3c5a3c;              /* 榴莲叶绿 */
  --warn:#b00020;
  --line:#d2d2d7; --line-dark:#424245;
  --radius:22px; --radius-sm:14px;
  --maxw:1080px; --maxw-narrow:740px;
  --ease:cubic-bezier(.4,0,.2,1);
  --shadow:0 4px 24px rgba(0,0,0,.06);
  --shadow-lg:0 20px 60px rgba(0,0,0,.12);
  --sf:"SF Pro Display","SF Pro Text",-apple-system,BlinkMacSystemFont,"PingFang SC","Helvetica Neue","Microsoft YaHei",sans-serif;
}
*{margin:0;padding:0;box-sizing:border-box;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
html{scroll-behavior:smooth;background:var(--bg)}
body{font-family:var(--sf);color:var(--text);line-height:1.5;overflow-x:hidden;background:var(--bg)}
img{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
section{position:relative}

/* ============ TYPOGRAPHY ============ */
.eyebrow{font-size:17px;font-weight:600;letter-spacing:.02em;color:var(--accent);margin-bottom:14px}
.eyebrow.blue{color:var(--accent-2)}
.h-display{font-size:clamp(40px,7vw,80px);font-weight:700;letter-spacing:-.015em;line-height:1.05}
.h-section{font-size:clamp(32px,5vw,56px);font-weight:700;letter-spacing:-.02em;line-height:1.08}
.h-block{font-size:clamp(24px,3vw,36px);font-weight:600;letter-spacing:-.01em;line-height:1.15}
.lead{font-size:clamp(19px,2vw,24px);font-weight:400;color:var(--text-soft);line-height:1.5;letter-spacing:.004em}
.lead.inv{color:var(--text-soft)}
.body{font-size:17px;line-height:1.6;color:var(--text-soft)}
.body.inv{color:var(--text-soft)}
.body strong,.lead strong{color:var(--text);font-weight:600}
.body.inv strong,.lead.inv strong{color:var(--text)}
.takeaway{font-size:clamp(22px,2.6vw,32px);font-weight:600;line-height:1.3;letter-spacing:-.01em;max-width:880px}
.takeaway.inv{color:var(--text)}
.takeaway .hl,.lead .hl,.body .hl{color:var(--accent)}
.gold{color:var(--accent)}

/* ============ LAYOUT ============ */
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 22px}
.wrap.narrow{max-width:var(--maxw-narrow)}
.center{text-align:center}
.mx-auto{margin-left:auto;margin-right:auto}
.sec{padding:clamp(70px,11vw,130px) 0}

/* ============ NAV (APPLE STICKY) ============ */
.nav{position:fixed;top:0;left:0;right:0;height:48px;background:rgba(255,255,255,.72);backdrop-filter:saturate(180%) blur(20px);-webkit-backdrop-filter:saturate(180%) blur(20px);border-bottom:1px solid rgba(0,0,0,.08);z-index:1000;transition:background .3s var(--ease)}
.nav.dark{background:rgba(0,0,0,.72);border-bottom:1px solid rgba(255,255,255,.12)}
.nav-inner{max-width:1080px;margin:0 auto;padding:0 22px;height:100%;display:flex;align-items:center;justify-content:space-between;gap:18px}
.nav-brand{font-size:15px;font-weight:600;letter-spacing:-.01em;white-space:nowrap;display:flex;align-items:center;gap:9px;color:var(--text)}
.nav.dark .nav-brand{color:var(--text-inv)}
.nav-brand .dot{width:9px;height:9px;border-radius:50%;background:var(--accent);display:inline-block;flex:none}
.nav-logo{height:30px;width:auto;display:block;flex:none;transition:filter .3s var(--ease)}
.nav.dark .nav-logo{filter:brightness(0) invert(1)}   /* 深色背景下 LOGO 反白 */
.nav-menu{display:flex;gap:0;list-style:none;overflow-x:auto;scrollbar-width:none;align-items:center}
.nav-menu::-webkit-scrollbar{display:none}
.nav-menu a{font-size:12.5px;color:var(--text-soft);padding:6px 11px;border-radius:8px;white-space:nowrap;transition:.2s}
.nav.dark .nav-menu a{color:var(--text-inv-soft)}
.nav-menu a:hover{color:var(--text);background:var(--bg-soft)}
.nav.dark .nav-menu a:hover{color:var(--text-inv);background:rgba(255,255,255,.1)}
.nav-cta{font-size:12.5px;font-weight:600;color:#fff;background:#1f6b50;padding:7px 16px;border-radius:100px;white-space:nowrap;transition:.25s var(--ease);box-shadow:0 1px 3px rgba(31,107,80,.3)}
.nav-cta:hover{background:#15543e;transform:translateY(-1px);box-shadow:0 3px 8px rgba(31,107,80,.4)}
@media(max-width:760px){.nav-menu{display:none}}

/* ============ HERO ============ */
.hero{min-height:100vh;display:flex;flex-direction:column;justify-content:flex-end;padding:120px 0 70px;color:var(--text-inv);background:#000;overflow:hidden}
.hero-media{position:absolute;inset:0;z-index:0;background:#000}
.hero-media video,.hero-media img{width:100%;height:100%;object-fit:cover;opacity:.6}
.hero-media::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(0,0,0,.45) 0%,rgba(0,0,0,.2) 40%,rgba(0,0,0,.78) 100%)}
.hero-content{position:relative;z-index:2}
.hero .eyebrow{color:var(--accent)}
.hero h1{color:#fff;font-size:clamp(38px,6.5vw,76px);font-weight:700;letter-spacing:-.02em;line-height:1.04;margin-bottom:24px}
.hero .sub{font-size:clamp(18px,2vw,22px);color:var(--text-inv-soft);max-width:680px;line-height:1.5;margin-bottom:40px}
.hero-meta{display:flex;flex-wrap:wrap;gap:34px;align-items:center;color:var(--text-inv-soft);font-size:14px}
.hero-meta strong{color:#fff;font-weight:600}
.scroll-hint{position:absolute;bottom:26px;left:50%;transform:translateX(-50%);z-index:3;font-size:11px;color:var(--text-inv-soft);letter-spacing:.08em;text-transform:uppercase;display:flex;flex-direction:column;align-items:center;gap:8px;opacity:.8}
.scroll-hint::after{content:"";width:1px;height:30px;background:linear-gradient(180deg,var(--text-inv-soft),transparent);animation:scrolldown 2s var(--ease) infinite}
@keyframes scrolldown{0%{transform:scaleY(0);transform-origin:top}50%{transform:scaleY(1);transform-origin:top}50.1%{transform-origin:bottom}100%{transform:scaleY(0);transform-origin:bottom}}

/* ============ STAT BAND ============ */
.statband{background:var(--bg-soft);color:var(--text);padding:clamp(60px,9vw,110px) 0}
.statband .takeaway.inv{margin:0 auto 60px;text-align:center}
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.stat{padding:32px 18px;border-radius:var(--radius);background:#fff;text-align:center;box-shadow:var(--shadow)}
.stat .num{font-size:clamp(38px,5vw,64px);font-weight:700;letter-spacing:-.03em;background:linear-gradient(135deg,var(--accent),var(--accent-hi));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;line-height:1;margin-bottom:10px}
.stat .num .unit{font-size:.42em;font-weight:600;color:var(--text-soft);-webkit-text-fill-color:var(--text-soft);margin-left:3px}
.stat .lbl{font-size:13px;color:var(--text-soft);line-height:1.4}
@media(max-width:720px){.stats{grid-template-columns:repeat(2,1fr)}}

/* ============ GENERIC CARD / GRID ============ */
.grid{display:grid;gap:18px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
@media(max-width:820px){.grid-2,.grid-3{grid-template-columns:1fr}.grid-4{grid-template-columns:repeat(2,1fr)}}
@media(max-width:560px){.grid-4{grid-template-columns:1fr}}
.card{background:var(--bg-soft);border-radius:var(--radius);padding:34px 30px;transition:transform .4s var(--ease),box-shadow .4s var(--ease)}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}
.card .idx{font-size:13px;font-weight:700;color:var(--accent);letter-spacing:.05em;margin-bottom:14px}
.card h3{font-size:21px;font-weight:600;letter-spacing:-.01em;margin-bottom:12px;line-height:1.25}
.card p{font-size:15.5px;color:var(--text-soft);line-height:1.55}
.card.dark{background:#fff;color:var(--text);border:1px solid var(--line)}
.card.dark h3{color:var(--text)}
.card.dark p{color:var(--text-soft)}
.card.dark .idx{color:var(--accent)}
.card.link{display:block;cursor:pointer}
.card .card-cta{margin-top:18px;font-size:14px;font-weight:600;color:var(--accent);display:inline-flex;align-items:center;gap:6px;transition:gap .25s var(--ease)}
.card.link:hover .card-cta{gap:12px}

/* SECTION INTRO */
.sec-head{margin-bottom:60px;max-width:820px}
.sec-head.center{margin-left:auto;margin-right:auto;text-align:center}
.sec-num{display:inline-flex;align-items:center;gap:10px;font-size:13px;font-weight:700;color:var(--accent);letter-spacing:.12em;text-transform:uppercase;margin-bottom:18px}
.sec-num::before{content:"";width:28px;height:2px;background:var(--accent)}

/* ============ FEATURE MEDIA (TOUT) ============ */
.tout{position:relative;border-radius:var(--radius);overflow:hidden;background:#000}
.tout img,.tout video{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.tout.full{min-height:clamp(360px,52vw,560px)}
.tout-caption{position:absolute;left:0;right:0;bottom:0;padding:clamp(26px,4vw,46px);color:#fff;background:linear-gradient(180deg,transparent,rgba(0,0,0,.78));z-index:2}
.tout-caption .eyebrow{color:var(--accent)}
.tout-caption h3{font-size:clamp(22px,2.6vw,32px);font-weight:600;letter-spacing:-.01em;line-height:1.2;margin-bottom:10px}
.tout-caption p{font-size:15.5px;color:var(--text-inv-soft);max-width:560px;line-height:1.5}

/* SPEC TILES */
.specs{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-top:18px}
.specs.two{grid-template-columns:repeat(2,1fr)}
.spec{background:var(--bg-soft);border-radius:var(--radius-sm);padding:24px 20px}
.spec.dark{background:#fff;color:var(--text);border:1px solid var(--line)}
.spec .v{font-size:clamp(24px,3vw,34px);font-weight:700;letter-spacing:-.02em;color:var(--text);line-height:1.1}
.spec.dark .v{color:var(--text)}
.spec .v .u{font-size:.5em;font-weight:600;color:var(--text-soft);margin-left:2px}
.spec.dark .v .u{color:var(--text-soft)}
.spec .k{font-size:13px;color:var(--text-soft);margin-top:8px;line-height:1.4}
.spec.dark .k{color:var(--text-soft)}
@media(max-width:720px){.specs{grid-template-columns:repeat(2,1fr)}.specs.two{grid-template-columns:1fr}}

/* ============ PROCESS STEPS ============ */
.steps{counter-reset:step;display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.step{background:var(--bg-soft);border-radius:var(--radius);padding:32px 28px;position:relative;transition:transform .4s var(--ease)}
.step:hover{transform:translateY(-4px)}
.step .n{counter-increment:step;font-size:13px;font-weight:700;color:var(--accent-2);letter-spacing:.06em;margin-bottom:14px}
.step .n::before{content:counter(step,decimal-leading-zero)}
.step h4{font-size:19px;font-weight:600;margin-bottom:10px;letter-spacing:-.01em}
.step p{font-size:14.5px;color:var(--text-soft);line-height:1.6}
@media(max-width:820px){.steps{grid-template-columns:1fr}}

/* ============ ARCHITECTURE LAYERS ============ */
.layer{display:grid;grid-template-columns:130px 1fr;gap:30px;padding:34px 0;border-bottom:1px solid var(--line);align-items:start}
.layer:last-child{border-bottom:0}
.layer .tag{font-size:13px;font-weight:700;color:var(--accent);letter-spacing:.04em}
.layer .tag span{display:block;color:var(--text-soft);font-weight:500;font-size:12px;margin-top:4px}
.layer .content h3{font-size:22px;font-weight:600;letter-spacing:-.01em;margin-bottom:10px}
.layer .content p{font-size:16px;color:var(--text-soft);line-height:1.6}
@media(max-width:640px){.layer{grid-template-columns:1fr;gap:8px}}

/* ============ TABLE ============ */
.tbl{width:100%;border-collapse:collapse;margin-top:8px;border-radius:var(--radius-sm);overflow:hidden;background:var(--bg-soft)}
.tbl th,.tbl td{padding:18px 22px;text-align:left;border-bottom:1px solid var(--line)}
.tbl th{font-size:13px;color:var(--text-soft);font-weight:600;background:rgba(0,0,0,.02)}
.tbl td{font-size:16px;font-weight:500}
.tbl tr:last-child td{border-bottom:0}
.tbl .grade{font-weight:700;color:var(--accent)}

/* ============ QUOTE BAND ============ */
.quote-band{background:var(--bg-soft);color:var(--text);padding:clamp(80px,12vw,140px) 0;text-align:center}
.quote-band .takeaway{margin:0 auto;max-width:780px}

/* ============ TIMELINE ============ */
.timeline{display:grid;grid-template-columns:repeat(4,1fr);gap:0;margin-top:30px;position:relative}
.timeline::before{content:"";position:absolute;top:18px;left:5%;right:5%;height:2px;background:var(--line)}
.tl{padding:0 18px;text-align:center;position:relative}
.tl .dot{width:38px;height:38px;border-radius:50%;background:var(--accent);color:#fff;font-size:14px;font-weight:700;display:flex;align-items:center;justify-content:center;margin:0 auto 18px;position:relative;z-index:2;border:4px solid var(--bg)}
.sec.dark-sec .tl .dot{border-color:var(--bg-soft)}
.tl h4{font-size:16px;font-weight:600;margin-bottom:6px}
.tl .wk{font-size:12px;color:var(--accent);font-weight:700;margin-bottom:10px;letter-spacing:.04em}
.tl p{font-size:13.5px;color:var(--text-soft);line-height:1.5}
@media(max-width:820px){.timeline{grid-template-columns:repeat(2,1fr);gap:30px 0}.timeline::before{display:none}}

/* ============ CASES ============ */
.case{background:var(--bg-soft);border-radius:var(--radius);overflow:hidden;transition:transform .4s var(--ease)}
.case:hover{transform:translateY(-4px)}
.case .cbody{padding:30px 28px}
.case .loc{font-size:12px;font-weight:700;color:var(--accent-2);letter-spacing:.05em;margin-bottom:12px}
.case h3{font-size:19px;font-weight:600;margin-bottom:12px;line-height:1.3}
.case p{font-size:14.5px;color:var(--text-soft);line-height:1.6;margin-bottom:18px}
.case .res{display:flex;gap:24px;flex-wrap:wrap;padding-top:18px;border-top:1px solid var(--line)}
.case .res .r .v{font-size:24px;font-weight:700;color:var(--accent);letter-spacing:-.02em}
.case .res .r .k{font-size:12px;color:var(--text-soft)}

/* ============ BADGE / TAG ============ */
.chip{display:inline-block;font-size:12.5px;font-weight:700;color:#fff;background:var(--accent);padding:4px 11px;border-radius:100px;letter-spacing:.02em}
.chip.soft{background:rgba(214,119,42,.12);color:var(--accent)}
.chip.blue{background:var(--accent-2)}
.chip.blue.soft{background:rgba(10,132,255,.12);color:var(--accent-2)}
.chip.green{background:var(--leaf)}
.chip.outline{background:transparent;border:1px solid var(--accent);color:var(--accent)}
.chip.inv-soft{background:rgba(31,107,80,.1);color:var(--accent)}

/* note label for vision/aspiration data */
.note-flag{display:inline-flex;align-items:center;gap:6px;font-size:12px;font-weight:600;color:var(--accent-2);background:rgba(10,132,255,.1);padding:5px 12px;border-radius:100px;margin-bottom:20px}
.note-flag::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--accent-2)}

/* ============ BUTTONS ============ */
.btn{display:inline-block;background:#1f6b50;color:#fff;font-size:16px;font-weight:600;padding:14px 30px;border-radius:100px;transition:.25s var(--ease);box-shadow:0 2px 6px rgba(31,107,80,.25)}
.btn:hover{background:#15543e;transform:translateY(-2px);box-shadow:0 6px 16px rgba(31,107,80,.35)}
.btn.dark{background:#fff;color:var(--text)}
.btn.dark:hover{background:var(--bg-soft)}
.btn.outline{background:transparent;border:1.5px solid currentColor;color:var(--accent)}
.btn.outline:hover{background:var(--accent);color:#fff}

/* ============ FOOTER ============ */
.footer{background:var(--bg-soft);color:var(--text);padding:clamp(80px,10vw,120px) 0 50px;border-top:1px solid var(--line)}
.footer-cta{background:#fff;color:var(--text);border-radius:var(--radius);padding:clamp(40px,6vw,70px);text-align:center;margin-bottom:80px;box-shadow:var(--shadow)}
.footer-cta h2{font-size:clamp(28px,4vw,46px);font-weight:700;letter-spacing:-.02em;line-height:1.15;margin-bottom:18px}
.footer-cta p{font-size:18px;color:var(--text-soft);max-width:560px;margin:0 auto 32px;line-height:1.5}
.foot-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr;gap:40px;padding-bottom:40px;border-bottom:1px solid var(--line-dark)}
@media(max-width:680px){.foot-grid{grid-template-columns:1fr;gap:34px}}
.foot-brand{font-size:17px;font-weight:600;margin-bottom:14px;display:flex;align-items:center;gap:9px}
.foot-brand .dot{width:9px;height:9px;border-radius:50%;background:var(--accent);display:inline-block}
.foot p{font-size:14px;color:var(--text-soft);line-height:1.7}
.foot h5{font-size:12px;font-weight:600;color:var(--text);text-transform:uppercase;letter-spacing:.06em;margin-bottom:16px}
.foot ul{list-style:none}
.foot li{font-size:14px;color:var(--text-soft);margin-bottom:10px}
.foot li strong{color:var(--text);font-weight:600}
.foot a:hover{color:var(--accent-hi)}
.foot-bottom{padding-top:28px;font-size:12px;color:var(--text-soft);display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;border-top:1px solid var(--line)}

/* ICP 备案（低调不显眼） */
.icp{margin-top:20px;text-align:center;font-size:11.5px;color:rgba(110,110,115,.5);letter-spacing:.02em}
.icp a{color:inherit;text-decoration:none;transition:color .2s}
.icp a:hover{color:rgba(161,161,166,.75)}

/* ============ SCROLL REVEAL ============ */
.reveal{opacity:0;transform:translateY(34px);transition:opacity .8s var(--ease),transform .8s var(--ease)}
.reveal.in{opacity:1;transform:none}
.reveal.d1{transition-delay:.08s}.reveal.d2{transition-delay:.16s}.reveal.d3{transition-delay:.24s}.reveal.d4{transition-delay:.32s}
@media(prefers-reduced-motion:reduce){.reveal{opacity:1;transform:none;transition:none}html{scroll-behavior:auto}}

/* ============ DARK SECTION HELPER ============ */
.dark-sec{background:var(--bg-soft);color:var(--text)}
.dark-sec .body{color:var(--text-inv-soft)}
.dark-sec .body strong{color:var(--text)}
.dark-sec .lead{color:var(--text-soft)}

/* ============ TWO-COL TOUT GRID ============ */
.tgrid{display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center}
.tgrid.wide-l{grid-template-columns:1.1fr .9fr}
.tgrid.wide-r{grid-template-columns:.9fr 1.1fr}
@media(max-width:860px){.tgrid,.tgrid.wide-l,.tgrid.wide-r{grid-template-columns:1fr;gap:32px}}

/* ============ WORLD MAP PIN LIST ============ */
.pin-list{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
@media(max-width:760px){.pin-list{grid-template-columns:1fr}}
.pin{background:#fff;border-radius:var(--radius);padding:28px 24px;color:var(--text);border:1px solid var(--line)}
.pin .pin-flag{font-size:12px;font-weight:700;color:var(--accent-hi);letter-spacing:.05em;margin-bottom:10px}
.pin h4{font-size:19px;font-weight:600;margin-bottom:10px;color:var(--text)}
.pin p{font-size:14px;color:var(--text-soft);line-height:1.6}

/* nav jump offset */
[id]{scroll-margin-top:70px}