/* ============================================================
   HSINHO Electronics — design system
   Palette derived from logo: deep navy + bright tech blue on white/silver
   ============================================================ */
:root{
  --navy:#0a2a6b;        /* logo deep navy */
  --navy-900:#071f50;
  --navy-700:#123a8a;
  --blue:#1a7fff;        /* logo accent */
  --blue-600:#0e6ae6;
  --ink:#0d1526;         /* near-black text */
  --slate:#5a6680;       /* secondary text */
  --line:#e4e8f0;        /* hairline */
  --silver:#f4f6fa;      /* light panel */
  --silver-2:#eef1f7;
  --white:#ffffff;
  --carbon:#0c1220;      /* dark sections matching product photography */
  --carbon-2:#141c2e;
  --maxw:1200px;
  --r:14px;
  --shadow:0 1px 2px rgba(13,21,38,.04),0 8px 30px rgba(10,42,107,.07);
  --shadow-lg:0 20px 60px rgba(10,42,107,.16);
  --font-display:"Sora","Segoe UI",system-ui,sans-serif;
  --font-body:"Inter","Segoe UI",system-ui,sans-serif;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:var(--font-body);color:var(--ink);background:var(--white);
  line-height:1.6;-webkit-font-smoothing:antialiased;font-size:16px;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px}
.eyebrow{font-family:var(--font-display);font-size:.74rem;font-weight:600;letter-spacing:.18em;
  text-transform:uppercase;color:var(--blue);display:inline-flex;align-items:center;gap:10px}
.eyebrow::before{content:"";width:26px;height:2px;background:var(--blue);display:inline-block}
h1,h2,h3,h4{font-family:var(--font-display);line-height:1.12;letter-spacing:-.02em;color:var(--ink);font-weight:700}
h2{font-size:clamp(1.8rem,3.4vw,2.7rem)}
h3{font-size:1.3rem}
p{color:var(--slate)}
section{padding:88px 0}

/* ---------- top bar ---------- */
.topbar{background:var(--navy-900);color:#c5d2ee;font-size:.82rem}
.topbar .wrap{display:flex;justify-content:space-between;align-items:center;height:42px;flex-wrap:wrap}
.topbar a{color:#c5d2ee;display:inline-flex;align-items:center;gap:7px}
.topbar a:hover{color:#fff}
.topbar .tb-left{display:flex;gap:22px}
.topbar .langs{display:flex;gap:14px;font-size:.78rem}
.topbar .langs a.active{color:#fff;font-weight:600}

/* ---------- header / nav ---------- */
header.site{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);
  backdrop-filter:saturate(180%) blur(12px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;height:78px}
.nav .logo img{height:38px;width:auto}
.menu{display:flex;gap:30px;list-style:none;align-items:center}
.menu>li>a{font-family:var(--font-display);font-weight:500;font-size:.94rem;color:var(--ink);
  padding:8px 0;position:relative;transition:color .2s}
.menu>li>a:hover,.menu>li>a.active{color:var(--navy)}
.menu>li>a.active::after{content:"";position:absolute;left:0;bottom:-2px;width:100%;height:2px;background:var(--blue)}
.has-sub{position:relative}
.submenu{position:absolute;top:calc(100% + 14px);left:50%;transform:translateX(-50%) translateY(8px);
  background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:var(--shadow-lg);
  min-width:230px;padding:8px;opacity:0;visibility:hidden;transition:.22s}
.has-sub:hover .submenu{opacity:1;visibility:visible;transform:translateX(-50%) translateY(0)}
.submenu a{display:block;padding:11px 14px;border-radius:8px;font-size:.9rem;color:var(--slate)}
.submenu a:hover{background:var(--silver);color:var(--navy)}
.btn{display:inline-flex;align-items:center;gap:9px;font-family:var(--font-display);font-weight:600;
  font-size:.92rem;padding:12px 22px;border-radius:10px;cursor:pointer;border:1.5px solid transparent;transition:.2s}
.btn-primary{background:var(--navy);color:#fff}
.btn-primary:hover{background:var(--navy-700);transform:translateY(-1px);box-shadow:0 8px 22px rgba(10,42,107,.25)}
.btn-ghost{border-color:rgba(255,255,255,.4);color:#fff}
.btn-ghost:hover{background:rgba(255,255,255,.1)}
.btn-outline{border-color:var(--line);color:var(--navy);background:#fff}
.btn-outline:hover{border-color:var(--navy);background:var(--silver)}
.btn-blue{background:var(--blue);color:#fff}
.btn-blue:hover{background:var(--blue-600);transform:translateY(-1px)}
.nav-cta{display:flex;align-items:center;gap:14px}
.burger{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:6px}
.burger span{width:24px;height:2px;background:var(--ink);transition:.2s}

/* ---------- hero / page header ---------- */
.page-hero{background:linear-gradient(180deg,var(--silver),#fff);padding:64px 0 56px;border-bottom:1px solid var(--line)}
.page-hero h1{font-size:clamp(2.1rem,4vw,3.1rem)}
.page-hero p{font-size:1.08rem;max-width:680px;margin-top:14px}
.crumb{font-size:.82rem;color:var(--slate);margin-bottom:18px}
.crumb a:hover{color:var(--navy)}

/* ---------- buttons row ---------- */
.btn-row{display:flex;gap:14px;flex-wrap:wrap;margin-top:30px}

/* ---------- trust strip ---------- */
.trust{background:var(--carbon);color:#cdd6ea}
.trust .wrap{display:grid;grid-template-columns:repeat(5,1fr);gap:0;padding:0}
.trust-item{padding:30px 22px;text-align:center;border-right:1px solid rgba(255,255,255,.07)}
.trust-item:last-child{border-right:0}
.trust-item .n{font-family:var(--font-display);font-weight:700;color:#fff;font-size:1.55rem;letter-spacing:-.02em}
.trust-item .l{font-size:.82rem;color:#9fb0d2;margin-top:6px;letter-spacing:.02em}

/* ---------- section header ---------- */
.sec-head{max-width:720px;margin-bottom:48px}
.sec-head h2{margin-top:16px}
.sec-head p{margin-top:16px;font-size:1.05rem}
.center{text-align:center;margin-left:auto;margin-right:auto}
.center .eyebrow{justify-content:center}

/* ---------- product cards ---------- */
.grid{display:grid;gap:26px}
.g-3{grid-template-columns:repeat(3,1fr)}
.g-4{grid-template-columns:repeat(4,1fr)}
.g-2{grid-template-columns:repeat(2,1fr)}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--r);overflow:hidden;
  transition:.25s;box-shadow:var(--shadow)}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:#cdd8ee}
.card .ph{aspect-ratio:16/9;overflow:hidden;background:var(--carbon)}
.card .ph img{width:100%;height:100%;object-fit:cover;transition:.4s}
.card:hover .ph img{transform:scale(1.05)}
.card .body{padding:22px}
.card .body h3{font-size:1.12rem}
.card .body p{font-size:.92rem;margin-top:9px}
.card .more{margin-top:16px;font-family:var(--font-display);font-weight:600;font-size:.86rem;
  color:var(--navy);display:inline-flex;align-items:center;gap:7px}
.card .more svg{transition:.2s}.card:hover .more svg{transform:translateX(4px)}
.tag{display:inline-block;font-size:.72rem;font-weight:600;letter-spacing:.04em;color:var(--blue);
  background:#eaf2ff;padding:4px 11px;border-radius:20px;margin-bottom:12px;font-family:var(--font-display)}

/* ---------- feature / capability ---------- */
.cap-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);
  border:1px solid var(--line);border-radius:var(--r);overflow:hidden}
.cap{background:#fff;padding:32px 28px;transition:.2s}
.cap:hover{background:var(--silver)}
.cap .ic{width:48px;height:48px;border-radius:12px;background:var(--navy);color:#fff;display:flex;
  align-items:center;justify-content:center;margin-bottom:18px}
.cap h3{font-size:1.08rem}
.cap p{font-size:.9rem;margin-top:8px}
.cap .en{font-size:.78rem;color:var(--blue);font-family:var(--font-display);font-weight:600;letter-spacing:.04em;margin-top:4px}

/* ---------- split ---------- */
.split{display:grid;grid-template-columns:1fr 1fr;gap:60px;align-items:center}
.split img{border-radius:var(--r);box-shadow:var(--shadow-lg);width:100%}
.split.dark{align-items:stretch}
.feat-list{list-style:none;margin-top:24px;display:grid;gap:14px}
.feat-list li{display:flex;gap:13px;align-items:flex-start;font-size:.96rem;color:var(--ink)}
.feat-list li svg{flex-shrink:0;margin-top:3px;color:var(--blue)}

/* ---------- dark section ---------- */
.dark-sec{background:var(--carbon);color:#cdd6ea}
.dark-sec h2{color:#fff}.dark-sec h3{color:#fff}
.dark-sec p{color:#9fb0d2}
.dark-sec .eyebrow{color:#5fa0ff}.dark-sec .eyebrow::before{background:#5fa0ff}

/* ---------- certs ---------- */
.certs{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;margin-top:8px}
.cert{border:1px solid rgba(255,255,255,.12);border-radius:var(--r);padding:26px;background:var(--carbon-2)}
.cert .code{font-family:var(--font-display);font-weight:700;color:#fff;font-size:1.05rem}
.cert .desc{font-size:.86rem;color:#9fb0d2;margin-top:8px}
.cert .badge{font-size:.7rem;color:#5fa0ff;letter-spacing:.1em;text-transform:uppercase;font-weight:600}

/* ---------- application tabs ---------- */
.app-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.app{border:1px solid var(--line);border-radius:var(--r);padding:28px;background:#fff;transition:.2s}
.app:hover{border-color:var(--navy);box-shadow:var(--shadow)}
.app h3{font-size:1.1rem}.app .en{color:var(--blue);font-size:.82rem;font-family:var(--font-display);font-weight:600;margin-bottom:14px}
.chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:14px}
.chip{font-size:.78rem;background:var(--silver);color:var(--slate);padding:5px 12px;border-radius:8px}

/* ---------- CTA band ---------- */
.cta-band{background:linear-gradient(120deg,var(--navy-900),var(--navy) 60%,var(--navy-700));color:#fff;
  text-align:center;border-radius:0}
.cta-band h2{color:#fff}.cta-band p{color:#c5d2ee;max-width:560px;margin:14px auto 0}

/* ---------- contact form ---------- */
.form-grid{display:grid;grid-template-columns:1.2fr .8fr;gap:50px}
.field{margin-bottom:18px}
.field label{display:block;font-size:.84rem;font-weight:600;font-family:var(--font-display);margin-bottom:7px;color:var(--ink)}
.field input,.field select,.field textarea{width:100%;padding:13px 15px;border:1px solid var(--line);
  border-radius:10px;font-family:var(--font-body);font-size:.94rem;background:#fff;transition:.2s}
.field input:focus,.field select:focus,.field textarea:focus{outline:none;border-color:var(--blue);
  box-shadow:0 0 0 3px rgba(26,127,255,.12)}
.field textarea{min-height:120px;resize:vertical}
.f2{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.info-block{background:var(--silver);border-radius:var(--r);padding:32px;border:1px solid var(--line)}
.info-row{display:flex;gap:14px;align-items:flex-start;padding:16px 0;border-bottom:1px solid var(--line)}
.info-row:last-child{border-bottom:0}
.info-row .ic{width:42px;height:42px;border-radius:11px;background:var(--navy);color:#fff;display:flex;
  align-items:center;justify-content:center;flex-shrink:0}
.info-row .lab{font-size:.76rem;color:var(--slate);text-transform:uppercase;letter-spacing:.08em}
.info-row .val{font-weight:600;color:var(--ink);font-size:.96rem}

/* ---------- footer ---------- */
footer.site{background:var(--carbon);color:#9fb0d2;padding:64px 0 0}
.foot-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1.2fr;gap:40px;padding-bottom:48px}
footer.site .flogo{height:34px;margin-bottom:18px}
footer.site .fdesc{font-size:.88rem;color:#8595b8;max-width:320px}
footer.site h4{color:#fff;font-size:.82rem;text-transform:uppercase;letter-spacing:.1em;margin-bottom:18px;font-family:var(--font-display)}
footer.site ul{list-style:none;display:grid;gap:11px}
footer.site ul a{font-size:.9rem;color:#9fb0d2}
footer.site ul a:hover{color:#fff}
.foot-contact{font-size:.88rem;display:grid;gap:12px}
.foot-contact div{display:flex;gap:10px;color:#9fb0d2}
.foot-bottom{border-top:1px solid rgba(255,255,255,.1);padding:22px 0;display:flex;
  justify-content:space-between;flex-wrap:wrap;gap:12px;font-size:.82rem;color:#6f7ea0}

/* ---------- misc ---------- */
.stat-row{display:grid;grid-template-columns:repeat(4,1fr);gap:30px;margin-top:10px}
.stat .num{font-family:var(--font-display);font-weight:700;font-size:2.6rem;color:var(--navy);letter-spacing:-.03em}
.dark-sec .stat .num{color:#fff}
.stat .lab{color:var(--slate);font-size:.9rem;margin-top:4px}
.dark-sec .stat .lab{color:#9fb0d2}
.note{background:#eaf2ff;border-left:3px solid var(--blue);padding:16px 20px;border-radius:0 10px 10px 0;
  font-size:.9rem;color:var(--navy-900);margin-top:20px}

/* ---------- responsive ---------- */
@media(max-width:980px){
  .g-4{grid-template-columns:repeat(2,1fr)}
  .g-3,.cap-grid,.app-grid,.certs{grid-template-columns:1fr 1fr}
  .split,.form-grid{grid-template-columns:1fr;gap:34px}
  .trust .wrap{grid-template-columns:repeat(2,1fr)}
  .trust-item:nth-child(odd){border-right:1px solid rgba(255,255,255,.07)}
}
@media(max-width:680px){
  section{padding:60px 0}
  .menu,.nav-cta .btn-row{display:none}
  .burger{display:flex}
  .nav-cta{gap:0}
  .g-4,.g-3,.g-2,.cap-grid,.app-grid,.certs,.stat-row,.foot-grid{grid-template-columns:1fr}
  .trust .wrap{grid-template-columns:1fr 1fr}
  .f2{grid-template-columns:1fr}
  .topbar .tb-left{gap:14px;font-size:.74rem}
  .mobile-menu.open{display:block}
}
.mobile-menu{display:none;background:#fff;border-bottom:1px solid var(--line);padding:16px 24px}
.mobile-menu a{display:block;padding:12px 0;font-family:var(--font-display);font-weight:500;border-bottom:1px solid var(--silver)}
.mobile-menu .btn{margin-top:14px;width:100%;justify-content:center}

/* ===== Why HSINHO section ===== */
.why-sec{background:var(--silver)}
.why-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:18px;margin-top:8px}
.why-card{background:#fff;border:1px solid var(--line);border-radius:14px;padding:26px 20px;text-align:center;transition:.2s}
.why-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:transparent}
.why-ic{width:52px;height:52px;margin:0 auto 16px;color:var(--blue)}
.why-ic svg{width:100%;height:100%}
.why-card h3{font-size:1.02rem;margin-bottom:8px;line-height:1.3}
.why-card p{font-size:.86rem;color:#5a6b85;line-height:1.5}
@media(max-width:1000px){.why-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:560px){.why-grid{grid-template-columns:1fr}}

/* ===== Certificate gallery ===== */
.cert-gallery{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-top:8px}
.cert-card{margin:0;background:#fff;border:1px solid var(--line);border-radius:14px;overflow:hidden;cursor:pointer;transition:.2s;display:flex;flex-direction:column}
.cert-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:var(--blue)}
.cert-img{background:#f2f5fb;padding:18px;display:flex;align-items:center;justify-content:center;border-bottom:1px solid var(--line)}
.cert-img img{width:100%;height:280px;object-fit:contain}
.cert-card figcaption{padding:20px 22px}
.cert-card h3{font-size:1.05rem;margin-bottom:6px}
.cert-std{font-family:var(--font-display);font-size:.82rem;color:var(--blue);font-weight:600;margin-bottom:10px}
.cert-valid{font-size:.84rem;color:#5a6b85;margin-bottom:14px}
.cert-view{display:inline-flex;align-items:center;gap:6px;font-size:.82rem;font-weight:600;color:var(--navy)}
.cert-view svg{transition:transform .2s}
.cert-card:hover .cert-view svg{transform:translateX(4px)}
@media(max-width:820px){.cert-gallery{grid-template-columns:1fr;max-width:420px;margin:8px auto 0}}

/* ===== Lightbox ===== */
.cert-lightbox{display:none;position:fixed;inset:0;z-index:1000;background:rgba(8,18,40,.92);padding:40px;cursor:zoom-out}
.cert-lightbox.open{display:flex;align-items:center;justify-content:center}
.cert-lightbox figure{margin:0;max-width:92vw;max-height:92vh;display:flex;flex-direction:column;align-items:center}
.cert-lightbox img{max-width:100%;max-height:84vh;object-fit:contain;border-radius:8px;box-shadow:0 20px 60px rgba(0,0,0,.5);background:#fff}
.cert-lightbox figcaption{color:#cdd8ee;margin-top:16px;font-family:var(--font-display);font-size:.95rem}
.cert-close{position:absolute;top:24px;right:34px;color:#fff;font-size:2.6rem;line-height:1;cursor:pointer;font-weight:300}
.cert-close:hover{color:var(--blue)}

/* ===== FAQ (SEO/GEO) ===== */
.faq-section{padding:64px 0;background:var(--silver);border-top:1px solid var(--line)}
.faq-section .faq-head{text-align:center;max-width:720px;margin:0 auto 36px}
.faq-section .faq-head h2{font-size:clamp(1.5rem,3vw,2rem)}
.faq-section .faq-head p{color:#5a6b85;margin-top:10px}
.faq-list{max-width:820px;margin:0 auto;display:flex;flex-direction:column;gap:14px}
.faq-item{background:#fff;border:1px solid var(--line);border-radius:14px;overflow:hidden;transition:border-color .2s,box-shadow .2s}
.faq-item[open]{border-color:var(--blue);box-shadow:var(--shadow-lg)}
.faq-item summary{list-style:none;cursor:pointer;padding:20px 24px;font-family:var(--font-display);font-weight:600;font-size:1.02rem;color:var(--navy);display:flex;justify-content:space-between;align-items:center;gap:16px}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{content:"+";font-size:1.5rem;font-weight:400;color:var(--blue);flex-shrink:0;transition:transform .2s}
.faq-item[open] summary::after{transform:rotate(45deg)}
.faq-item .faq-a{padding:0 24px 22px;color:#465670;line-height:1.7;font-size:.96rem}