/* =========================================================================
   合和成汽车零件企业 · HOE HAP SENG AUTO ENTERPRISE
   Black-red industrial / motorsport system · Oswald + Noto Sans SC · 中文 dark
   正品汽车零件零售，引流 Shopee + TikTok。
   ========================================================================= */

:root{
  --black:#0D0D0F;
  --surface:#161619;
  --surface-2:#1E1E23;
  --ink:#F2F0EC;
  --ink-dim:#C7C5C0;
  --muted:#94949B;
  --line:#2A2A31;
  --line-soft:#222227;

  --red:#E0231D;
  --red-deep:#B0140F;
  --red-bright:#FF453A;
  --steel:#C4C8D0;
  --steel-dim:#8A8E97;

  --header-h:74px;
  --maxw:1280px;
  --gutter:clamp(20px,5vw,72px);
  --r-sm:6px;--r-md:12px;--r-lg:18px;

  --display:"Oswald","Noto Sans SC",sans-serif;
  --body:"Noto Sans SC",system-ui,-apple-system,sans-serif;
  --ease:cubic-bezier(.4,0,.15,1);
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;font-family:var(--body);background:var(--black);color:var(--ink);
  font-size:clamp(15.5px,1vw,16.5px);line-height:1.72;font-weight:400;
  -webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;overflow-x:hidden;
}
img{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
button{font:inherit;cursor:pointer;border:none;background:none;color:inherit}
ul{margin:0;padding:0;list-style:none}
h1,h2,h3,h4,p{margin:0}
::selection{background:var(--red);color:#fff}

.num{font-family:var(--display);font-variant-numeric:tabular-nums}
.eyebrow{
  font-family:var(--display);font-weight:600;font-size:.82rem;letter-spacing:.26em;
  text-transform:uppercase;color:var(--red-bright);display:inline-flex;align-items:center;gap:.7em;
}
.eyebrow::before{content:"";width:24px;height:3px;background:var(--red);display:inline-block}
.eyebrow.is-dim{color:var(--steel)}
.lead{font-size:clamp(1.04rem,1.5vw,1.2rem);color:var(--ink-dim);line-height:1.75}

.wrap{width:100%;max-width:var(--maxw);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-block:clamp(68px,8.5vw,128px)}

/* ---------- buttons ---------- */
.btn{
  --bg:var(--red);--bg-h:var(--red-deep);--fg:#fff;
  display:inline-flex;align-items:center;gap:.55em;background:var(--bg);color:var(--fg);
  padding:.9em 1.6em;border-radius:var(--r-sm);font-family:var(--display);font-weight:600;
  font-size:1rem;letter-spacing:.06em;text-transform:uppercase;
  transition:transform .2s var(--ease),box-shadow .2s var(--ease),background .2s var(--ease);
}
.btn:hover{transform:translateY(-2px);background:var(--bg-h);box-shadow:0 14px 26px -14px rgba(224,35,29,.6)}
.btn .arw{transition:transform .25s var(--ease)}
.btn:hover .arw{transform:translateX(3px)}
.btn--ghost{--bg:transparent;--bg-h:var(--surface-2);--fg:var(--ink);border:1.5px solid var(--line)}
.btn--ghost:hover{border-color:var(--steel-dim);box-shadow:none}
.btn--steel{--bg:var(--ink);--bg-h:#fff;--fg:var(--black)}
.btn--lg{padding:1.02em 1.9em;font-size:1.08rem}

/* focus-visible (a11y) */
a:focus-visible,button:focus-visible,.btn:focus-visible,summary:focus-visible,
input:focus-visible,select:focus-visible,textarea:focus-visible{
  outline:2px solid var(--red-bright);outline-offset:3px;border-radius:4px;
}

/* =========================================================================
   HEADER (sticky · counts toward first screen — R6)
   ========================================================================= */
.site-header{
  position:sticky;top:0;z-index:60;height:var(--header-h);display:flex;align-items:center;
  background:color-mix(in srgb,var(--black) 82%,transparent);backdrop-filter:saturate(1.2) blur(14px);
  border-bottom:1px solid transparent;transition:border-color .3s var(--ease),background .3s var(--ease);
}
.site-header.is-stuck{border-bottom-color:var(--line);background:color-mix(in srgb,var(--black) 92%,transparent)}
.site-header .wrap{display:flex;align-items:center;justify-content:space-between;gap:24px;width:100%}

.brand{display:flex;align-items:center;gap:12px;flex-shrink:0}
.brand img{height:50px;width:auto;display:block}
.footer__brand .brand img{height:54px}
.brand .mark{width:38px;height:42px;flex-shrink:0}
.brand .bz{display:flex;flex-direction:column;line-height:1.05}
.brand .zh{font-family:var(--display);font-weight:700;font-size:1.16rem;letter-spacing:.04em;color:var(--ink)}
.brand .en{font-family:var(--display);font-size:.56rem;letter-spacing:.22em;font-weight:500;color:var(--steel-dim);margin-top:3px;text-transform:uppercase}

.nav{display:flex;align-items:center;gap:clamp(16px,2.2vw,34px)}
.nav a{font-family:var(--display);font-weight:500;font-size:1rem;letter-spacing:.04em;color:var(--ink-dim);position:relative;padding-block:6px;text-transform:uppercase}
.nav a::after{content:"";position:absolute;left:0;bottom:0;height:2px;width:0;background:var(--red);transition:width .3s var(--ease)}
.nav a:hover{color:var(--ink)}
.nav a:hover::after{width:100%}
.header-cta{display:flex;align-items:center;gap:14px;flex-shrink:0}
.nav-toggle{display:none}

/* =========================================================================
   HERO (header + hero = one screen — R6) — photo + red scrim
   ========================================================================= */
.hero{position:relative;min-height:calc(100svh - var(--header-h));display:flex;align-items:flex-end;overflow:hidden;isolation:isolate}
.hero__media{position:absolute;inset:0;z-index:-2}
.hero__media img{width:100%;height:100%;object-fit:cover;object-position:50% 42%}
.hero__scrim{position:absolute;inset:0;z-index:-1;background:
  linear-gradient(to top,rgba(8,8,10,.96) 0%,rgba(8,8,10,.6) 38%,rgba(8,8,10,.32) 70%,rgba(8,8,10,.5) 100%),
  linear-gradient(100deg,rgba(8,8,10,.7) 0%,rgba(8,8,10,0) 60%)}
.hero__bar{position:absolute;left:0;right:0;bottom:0;height:5px;background:linear-gradient(90deg,var(--red) 0%,var(--red) 34%,transparent 34%,transparent 38%,var(--red) 38%,var(--red) 40%,transparent 40%);z-index:1;opacity:.9}
.hero__inner{padding-block:clamp(40px,6vw,82px);max-width:880px}
.hero h1{font-family:var(--display);font-weight:700;font-size:clamp(2.7rem,7vw,5.6rem);line-height:1.0;letter-spacing:.01em;color:#fff;text-shadow:0 2px 30px rgba(0,0,0,.4)}
.hero h1 em{font-style:normal;color:var(--red-bright)}
.hero .lead{color:var(--ink-dim);max-width:50ch;margin-top:1.3rem}
.hero__actions{display:flex;flex-wrap:wrap;gap:14px;margin-top:2rem}
.hero__meta{position:absolute;top:clamp(18px,3.4vw,32px);right:var(--gutter);z-index:1;text-align:right;color:var(--steel-dim);font-size:.74rem;letter-spacing:.1em;font-family:var(--display);text-transform:uppercase}
.hero__meta b{display:block;color:var(--ink);font-weight:600;font-size:.96rem;letter-spacing:.06em}
.hero__trust{display:flex;flex-wrap:wrap;gap:0;margin-top:2.6rem;border-top:1px solid rgba(255,255,255,.16);padding-top:1.3rem}
.hero__trust .ti{display:flex;flex-direction:column;padding-right:clamp(20px,3vw,42px);margin-right:clamp(20px,3vw,42px);border-right:1px solid rgba(255,255,255,.16)}
.hero__trust .ti:last-child{border-right:0;margin-right:0;padding-right:0}
.hero__trust b{font-family:var(--display);font-weight:700;font-size:1.7rem;color:#fff;letter-spacing:.02em}
.hero__trust span{color:var(--steel-dim);font-size:.86rem;margin-top:2px}
.scroll-cue{position:absolute;left:var(--gutter);bottom:24px;z-index:2;display:inline-flex;align-items:center;gap:10px;color:var(--steel-dim);font-size:.72rem;letter-spacing:.22em;text-transform:uppercase;font-family:var(--display)}
.scroll-cue i{width:30px;height:2px;background:var(--line);position:relative;overflow:hidden;display:inline-block}
.scroll-cue i::after{content:"";position:absolute;inset:0;background:var(--red);transform:translateX(-100%);animation:cue 2.2s var(--ease) infinite}
@keyframes cue{0%{transform:translateX(-100%)}55%,100%{transform:translateX(100%)}}

/* =========================================================================
   (A) TRUST STRIP — credentials band
   ========================================================================= */
.trust{background:var(--red);color:#fff}
.trust .wrap{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:18px 36px;padding-block:clamp(20px,2.5vw,30px)}
.trust .ti{display:flex;align-items:center;gap:12px}
.trust .ti svg{flex-shrink:0}
.trust .ti b{font-family:var(--display);font-weight:600;font-size:1.04rem;letter-spacing:.04em}
.trust .ti span{color:#fff;font-size:.86rem}

/* =========================================================================
   (B) CATALOG — parts categories grid (bento)
   ========================================================================= */
.catalog{background:var(--black)}
.catalog__head{display:flex;justify-content:space-between;align-items:flex-end;gap:24px;flex-wrap:wrap;margin-bottom:clamp(28px,4vw,52px)}
.catalog__head h2{font-family:var(--display);font-weight:700;font-size:clamp(2.1rem,4.4vw,3.4rem);line-height:1.02;color:#fff}
.cat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.cat-feature{grid-column:span 2;grid-row:span 2;position:relative;border-radius:var(--r-lg);overflow:hidden;min-height:380px;border:1px solid var(--line)}
.cat-feature img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;transition:transform .9s var(--ease)}
.cat-feature:hover img{transform:scale(1.06)}
.cat-feature__veil{position:absolute;inset:0;background:linear-gradient(to top,rgba(8,8,10,.92),rgba(8,8,10,.1) 62%)}
.cat-feature__b{position:absolute;inset:0;display:flex;flex-direction:column;justify-content:flex-end;padding:clamp(22px,2.4vw,32px)}
.cat-feature h3{font-family:var(--display);font-weight:700;font-size:clamp(1.7rem,2.6vw,2.4rem);color:#fff;line-height:1.02}
.cat-feature p{color:var(--ink-dim);font-size:.94rem;margin-top:.4rem;max-width:32ch}
.cat-tile{position:relative;background:var(--surface);border:1px solid var(--line);border-radius:var(--r-md);padding:20px 18px;display:flex;flex-direction:column;justify-content:space-between;min-height:182px;overflow:hidden;
  transition:transform .35s var(--ease),border-color .35s var(--ease),background .35s var(--ease)}
.cat-tile::before{content:"";position:absolute;left:0;top:0;bottom:0;width:3px;background:var(--red);transform:scaleY(0);transform-origin:top;transition:transform .35s var(--ease)}
.cat-tile:hover{transform:translateY(-4px);background:var(--surface-2);border-color:transparent}
.cat-tile:hover::before{transform:scaleY(1)}
.cat-tile .ic{color:var(--red-bright)}
.cat-tile .nm{font-family:var(--display);font-weight:600;font-size:1.34rem;color:#fff;letter-spacing:.01em}
.cat-tile .en{font-family:var(--display);font-size:.7rem;letter-spacing:.16em;text-transform:uppercase;color:var(--steel-dim);margin-top:2px}

/* =========================================================================
   (C) WHY — photo-less values band
   ========================================================================= */
.why{background:var(--black);position:relative}
.why__head{max-width:640px;margin-bottom:clamp(30px,4vw,54px)}
.why__head h2{font-family:var(--display);font-weight:700;font-size:clamp(2rem,3.8vw,3.1rem);line-height:1.04;color:#fff}
.why__head p{color:var(--ink-dim);margin-top:1rem;max-width:48ch}
.why__list{display:grid;grid-template-columns:repeat(4,1fr);gap:clamp(20px,3vw,40px)}
.why-row{padding-top:1.2rem;border-top:2px solid var(--red)}
.why-row .n{font-family:var(--display);font-weight:700;font-size:1rem;color:var(--red-bright);letter-spacing:.1em}
.why-row h3{font-family:var(--display);font-weight:600;font-size:1.32rem;color:#fff;margin:.5rem 0}
.why-row p{color:var(--muted);font-size:.92rem}

/* =========================================================================
   (E) BUY — Shopee + TikTok channels
   ========================================================================= */
.buy{background:var(--surface)}
.buy__head{text-align:center;max-width:620px;margin:0 auto clamp(30px,4vw,52px)}
.buy__head .eyebrow{justify-content:center}
.buy__head h2{font-family:var(--display);font-weight:700;font-size:clamp(2rem,4vw,3.1rem);line-height:1.04;color:#fff;margin-top:1rem}
.buy__head p{color:var(--ink-dim);margin-top:1rem}
.chan-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.chan{position:relative;border-radius:var(--r-lg);overflow:hidden;padding:clamp(28px,3.4vw,44px);border:1px solid var(--line);background:var(--surface-2);
  display:flex;flex-direction:column;gap:16px;transition:transform .35s var(--ease),border-color .35s var(--ease)}
.chan:hover{transform:translateY(-5px);border-color:var(--steel-dim)}
.chan__logo{display:inline-flex;align-items:center;gap:10px;font-family:var(--display);font-weight:700;font-size:1.5rem;color:#fff}
.chan p{color:var(--muted);font-size:.94rem;flex:1}
.chan--shopee{background:linear-gradient(160deg,#2a1410,var(--surface-2))}
.chan--tiktok{background:linear-gradient(160deg,#0f1416,var(--surface-2))}
.chan .btn{align-self:flex-start}

/* =========================================================================
   (F) CTA / CONTACT
   ========================================================================= */
.cta{background:var(--black)}
.cta__panel{position:relative;background:linear-gradient(120deg,var(--red-deep),var(--red));border-radius:var(--r-lg);overflow:hidden;
  padding:clamp(40px,6vw,80px);display:grid;grid-template-columns:1.4fr .6fr;gap:32px;align-items:center}
.cta__panel::after{content:"";position:absolute;right:-40px;bottom:-60px;width:300px;height:300px;border-radius:50%;background:rgba(0,0,0,.16)}
.cta__panel h2{font-family:var(--display);font-weight:700;font-size:clamp(2.1rem,4.4vw,3.4rem);line-height:1.0;color:#fff;position:relative}
.cta__panel p{color:#fff;margin-top:1rem;position:relative;max-width:40ch}
.cta__actions{display:flex;flex-direction:column;gap:12px;align-items:flex-start;position:relative}

/* =========================================================================
   FOOTER (R2 signature)
   ========================================================================= */
.site-footer{background:#070708;color:var(--muted);padding-top:clamp(56px,6.5vw,88px);border-top:1px solid var(--line)}
.footer__top{display:grid;grid-template-columns:1.6fr 1fr 1fr 1.2fr;gap:clamp(28px,4vw,56px);padding-bottom:clamp(40px,5vw,60px);border-bottom:1px solid var(--line)}
.footer__brand p{margin-top:16px;max-width:34ch;font-size:.92rem;line-height:1.7}
.footer__brand .reg{font-family:var(--display);color:var(--steel-dim);font-size:.82rem;letter-spacing:.06em;margin-top:12px}
.site-footer h3{color:#fff;font-family:var(--display);font-size:.82rem;letter-spacing:.16em;text-transform:uppercase;font-weight:600;margin-bottom:16px}
.footer__links li+li{margin-top:10px}
.footer__links a{font-size:.93rem;transition:color .25s var(--ease)}
.footer__links a:hover{color:var(--red-bright)}
.footer__contact p{font-size:.92rem;line-height:1.6;margin-bottom:10px}
.footer__contact a{color:var(--ink-dim)}
.footer__bottom{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;padding-block:24px;font-size:.83rem}
.footer__bottom .sign a{color:var(--ink);font-weight:600;border-bottom:1px solid var(--steel-dim)}
.footer__bottom .sign a:hover{border-color:#fff}

/* =========================================================================
   MOTION (reveal · reduced-motion + no-JS safe — D7)
   ========================================================================= */
.js [data-reveal]{opacity:0;transform:translateY(22px);transition:opacity .7s var(--ease),transform .7s var(--ease)}
.js [data-reveal].in{opacity:1;transform:none}
.js [data-reveal][data-d="1"]{transition-delay:.07s}
.js [data-reveal][data-d="2"]{transition-delay:.14s}
.js [data-reveal][data-d="3"]{transition-delay:.21s}
@media (prefers-reduced-motion:reduce){
  *{animation:none!important;scroll-behavior:auto!important}
  .js [data-reveal]{opacity:1!important;transform:none!important;transition:none!important}
  .scroll-cue i::after{display:none}
}

/* =========================================================================
   RESPONSIVE — tablet (≤1024) / mobile (≤760)  (R1)
   ========================================================================= */
@media (max-width:1024px){
  :root{--header-h:68px}
  .cta__panel{grid-template-columns:1fr}
  .cat-grid{grid-template-columns:repeat(2,1fr)}
  .cat-feature{grid-column:span 2;grid-row:auto;min-height:300px}
  .why__list{grid-template-columns:repeat(2,1fr);gap:28px 36px}
  .chan-grid{grid-template-columns:1fr}
  .footer__top{grid-template-columns:1fr 1fr}
}
@media (max-width:760px){
  :root{--header-h:60px}
  .nav,.header-cta .btn{display:none}
  .nav-toggle{display:inline-flex;align-items:center;justify-content:center;width:44px;height:44px;border-radius:8px;border:1.5px solid var(--line)}
  .nav-toggle span{position:relative;width:20px;height:2px;background:var(--ink);display:block}
  .nav-toggle span::before,.nav-toggle span::after{content:"";position:absolute;left:0;width:20px;height:2px;background:var(--ink);transition:.3s var(--ease)}
  .nav-toggle span::before{top:-6px}.nav-toggle span::after{top:6px}
  body.nav-open .nav-toggle span{background:transparent}
  body.nav-open .nav-toggle span::before{top:0;transform:rotate(45deg)}
  body.nav-open .nav-toggle span::after{top:0;transform:rotate(-45deg)}
  .mobile-nav{position:fixed;inset:var(--header-h) 0 0;z-index:55;background:var(--black);transform:translateY(-12px);opacity:0;visibility:hidden;pointer-events:none;transition:opacity .3s var(--ease),transform .3s var(--ease),visibility 0s linear .3s;display:flex;flex-direction:column;padding:26px var(--gutter) 40px;gap:4px;overflow-y:auto}
  body.nav-open .mobile-nav{transform:none;opacity:1;visibility:visible;pointer-events:auto;transition:opacity .3s var(--ease),transform .3s var(--ease),visibility 0s}
  .mobile-nav a{font-family:var(--display);font-size:1.7rem;font-weight:600;padding:13px 0;border-bottom:1px solid var(--line);color:var(--ink);text-transform:uppercase}
  .mobile-nav a.btn{margin-top:20px;align-self:flex-start;color:#fff;border-bottom:0;font-size:1rem;padding:.9em 1.6em}
  .hero__meta{display:none}
  .hero__trust .ti{width:46%;border-right:0;padding-right:0;margin-right:0;margin-bottom:8px}
  .cat-grid{grid-template-columns:1fr 1fr;gap:10px}
  .cat-feature{grid-column:span 2;min-height:260px}
  .why__list{grid-template-columns:1fr;gap:22px}
  .footer__top{grid-template-columns:1fr}
}
@media (min-width:761px){.mobile-nav{display:none}}