/* ==========================================================================
   Houmei White Oil — B2B Export Website
   Palette: deep blue #0b3c68 / brand blue #0e5aa7 / accent gold #f5b301
   ========================================================================== */

:root {
  --blue-900: #0b3c68;
  --blue-700: #0e5aa7;
  --blue-500: #1273c4;
  --blue-50: #eaf3fb;
  --gold: #f5b301;
  --ink: #16263a;
  --muted: #5a6b7f;
  --line: #dfe8f0;
  --bg: #ffffff;
  --bg-alt: #f5f9fc;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(11, 60, 104, .10);
  --shadow-lg: 0 18px 44px rgba(11, 60, 104, .16);
  --font: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 84px; }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

body[data-lang="zh"] { letter-spacing: .01em; }

img, svg { display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

.container { width: min(1180px, 92%); margin: 0 auto; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 14px 30px; border-radius: 999px;
  font-weight: 700; font-size: 15.5px; cursor: pointer;
  border: 2px solid transparent; transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
  font-family: inherit;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--blue-700); color: #fff; }
.btn-primary:hover { background: var(--blue-900); box-shadow: var(--shadow); }
.btn-accent { background: var(--gold); color: var(--blue-900); }
.btn-accent:hover { box-shadow: 0 12px 26px rgba(245, 179, 1, .45); }
.btn-ghost { border-color: rgba(255,255,255,.65); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.12); }
.btn-sm { padding: 10px 22px; font-size: 14px; }
.btn-block { width: 100%; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
  transition: box-shadow .25s ease;
}
.site-header.scrolled { box-shadow: 0 6px 24px rgba(11,60,104,.10); }
.header-inner { display: flex; align-items: center; gap: 28px; height: 74px; }

.logo { display: flex; align-items: center; gap: 11px; flex-shrink: 0; }
.logo-mark { width: 40px; height: 40px; }
.logo-text { display: flex; flex-direction: column; line-height: 1.15; }
.logo-text strong { font-size: 20px; letter-spacing: .08em; color: var(--blue-900); }
.logo-text small { font-size: 11px; color: var(--muted); font-weight: 500; }

.main-nav { display: flex; gap: 26px; margin-left: auto; }
.main-nav a {
  font-size: 14.5px; font-weight: 600; color: var(--ink);
  padding: 6px 2px; position: relative;
}
.main-nav a::after {
  content: ""; position: absolute; left: 0; bottom: 0;
  width: 0; height: 2px; background: var(--blue-700);
  transition: width .2s ease;
}
.main-nav a:hover::after { width: 100%; }

.header-actions { display: flex; align-items: center; gap: 14px; }
.lang-switch {
  display: inline-flex; border: 1.5px solid var(--line);
  border-radius: 999px; overflow: hidden; flex-shrink: 0;
}
.lang-btn {
  border: none; background: transparent; padding: 7px 15px;
  font-size: 13px; font-weight: 700; color: var(--muted);
  cursor: pointer; font-family: inherit; transition: all .18s ease;
}
.lang-btn.active { background: var(--blue-700); color: #fff; }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 24px; height: 2.5px; background: var(--blue-900); border-radius: 2px; transition: all .2s ease; }
.nav-toggle.open span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero { position: relative; color: #fff; overflow: hidden; }
.hero-bg { position: absolute; inset: 0; }
.hero-bg svg { width: 100%; height: 100%; object-fit: cover; }
.hero-inner {
  position: relative; z-index: 2;
  display: grid; grid-template-columns: 1.25fr .85fr; gap: 56px;
  align-items: center; padding: 88px 0 120px;
}

.eyebrow {
  display: inline-block; font-size: 13px; font-weight: 700;
  letter-spacing: .14em; text-transform: uppercase;
  color: var(--gold); margin-bottom: 18px;
}
.hero-copy h1 {
  font-size: clamp(34px, 4.6vw, 54px); line-height: 1.14;
  font-weight: 800; letter-spacing: -.01em; margin-bottom: 22px;
}
.hero-copy h1 span { display: block; }
.hero-sub { font-size: 17px; color: rgba(255,255,255,.88); max-width: 58ch; margin-bottom: 34px; }
.hero-cta { display: flex; gap: 16px; flex-wrap: wrap; }

.hero-card {
  background: rgba(255,255,255,.10);
  border: 1px solid rgba(255,255,255,.25);
  border-radius: 20px; padding: 28px;
  backdrop-filter: blur(14px);
  box-shadow: var(--shadow-lg);
}
.hero-card-head h3 { font-size: 19px; font-weight: 700; margin-bottom: 4px; }
.hero-card-tag {
  font-size: 12px; color: rgba(255,255,255,.75);
  text-transform: uppercase; letter-spacing: .08em;
}
.grade-list { margin: 18px 0 6px; display: grid; gap: 9px; }
.grade-list li {
  display: flex; justify-content: space-between; align-items: center;
  background: rgba(255,255,255,.10);
  border: 1px solid rgba(255,255,255,.14);
  border-radius: 10px; padding: 10px 16px; font-size: 14.5px;
}
.grade-list b { color: var(--gold); font-size: 14px; white-space: nowrap; margin-left: 12px; }
.hero-card-note { font-size: 12.5px; color: rgba(255,255,255,.7); margin-top: 10px; }

.trust-bar {
  position: relative; z-index: 2;
  background: rgba(11,60,104,.55);
  border-top: 1px solid rgba(255,255,255,.16);
  backdrop-filter: blur(8px);
}
.trust-inner { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; padding: 22px 0; }
.trust-item { display: flex; align-items: baseline; justify-content: center; gap: 12px; }
.trust-item b { font-size: 30px; font-weight: 800; color: var(--gold); line-height: 1; }
.trust-item b small { font-size: 15px; font-weight: 700; margin-left: 2px; }
.trust-item span { font-size: 13.5px; color: rgba(255,255,255,.85); }

/* ---------- Sections ---------- */
.section { padding: 92px 0; }
.section-alt { background: var(--bg-alt); }
.section-dark { background: var(--blue-900); color: #fff; }

.section-head { max-width: 720px; margin: 0 auto 54px; text-align: center; }
.section-eyebrow {
  font-size: 13px; font-weight: 700; letter-spacing: .14em;
  text-transform: uppercase; color: var(--blue-700); margin-bottom: 12px;
}
.section-dark .section-eyebrow { color: var(--gold); }
.section-head h2 { font-size: clamp(28px, 3.4vw, 38px); font-weight: 800; line-height: 1.2; letter-spacing: -.01em; }
.section-sub { color: var(--muted); margin-top: 16px; font-size: 16.5px; }
.section-head-light .section-sub { color: rgba(255,255,255,.8); }

/* ---------- Products ---------- */
.product-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.product-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 26px; display: flex; flex-direction: column;
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: var(--blue-500); }
.product-icon {
  width: 58px; height: 58px; border-radius: 14px;
  background: var(--blue-50); color: var(--blue-700);
  display: flex; align-items: center; justify-content: center; margin-bottom: 20px;
}
.product-icon svg { width: 30px; height: 30px; }
.product-card h3 { font-size: 19px; font-weight: 700; margin-bottom: 10px; }
.product-card > p { font-size: 14.5px; color: var(--muted); flex: 1; }
.spec-chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.spec-chips li {
  font-size: 12.5px; font-weight: 600; color: var(--blue-700);
  background: var(--blue-50); border-radius: 999px; padding: 5px 12px;
}

/* ---------- Spec table ---------- */
.spec-table-wrap { margin-top: 56px; }
.spec-table-wrap h3 { font-size: 21px; font-weight: 700; margin-bottom: 18px; text-align: center; }
.table-scroll { overflow-x: auto; border-radius: var(--radius); border: 1px solid var(--line); background: #fff; }
.spec-table { width: 100%; border-collapse: collapse; min-width: 720px; font-size: 14.5px; }
.spec-table th, .spec-table td { padding: 14px 18px; text-align: left; }
.spec-table thead th {
  background: var(--blue-900); color: #fff;
  font-weight: 700; font-size: 13.5px; letter-spacing: .02em; white-space: nowrap;
}
.spec-table tbody tr:nth-child(even) { background: var(--bg-alt); }
.spec-table tbody tr:hover { background: var(--blue-50); }
.table-note { text-align: center; color: var(--muted); font-size: 13.5px; margin-top: 14px; }

/* ---------- Applications ---------- */
.app-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.app-card {
  background: #fff; border-radius: var(--radius); padding: 30px 28px;
  border: 1px solid var(--line); position: relative; overflow: hidden;
  transition: transform .22s ease, box-shadow .22s ease;
}
.app-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lg); }
.app-num {
  position: absolute; top: 12px; right: 18px;
  font-size: 46px; font-weight: 800; color: var(--blue-50);
  line-height: 1; user-select: none;
}
.app-card h3 { font-size: 17.5px; font-weight: 700; color: var(--blue-900); margin-bottom: 8px; position: relative; }
.app-card p { font-size: 14.5px; color: var(--muted); position: relative; }

/* ---------- Quality ---------- */
.quality-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 60px; align-items: center; }
.quality-copy h2 { font-size: clamp(26px, 3.2vw, 36px); font-weight: 800; line-height: 1.22; margin-bottom: 18px; }
.quality-copy > p { color: var(--muted); margin-bottom: 22px; font-size: 15.5px; }
.check-list { display: grid; gap: 12px; }
.check-list li {
  position: relative; padding-left: 34px; font-weight: 600; font-size: 15px;
}
.check-list li::before {
  content: ""; position: absolute; left: 0; top: 2px;
  width: 21px; height: 21px; border-radius: 50%;
  background: var(--blue-700) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 13l4 4L19 7'/%3E%3C/svg%3E") center/13px no-repeat;
}
.cert-wall { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.cert-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 16px; text-align: center;
  transition: transform .2s ease, box-shadow .2s ease;
}
.cert-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.cert-card h4 {
  font-size: 19px; font-weight: 800; color: var(--blue-900);
  padding-bottom: 8px; margin-bottom: 8px;
  border-bottom: 2px solid var(--blue-50);
}
.cert-card p { font-size: 12.5px; color: var(--muted); font-weight: 600; }

/* ---------- Logistics ---------- */
.pack-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.pack-card {
  background: rgba(255,255,255,.07);
  border: 1px solid rgba(255,255,255,.18);
  border-radius: var(--radius); padding: 26px 22px;
  transition: background .2s ease, transform .2s ease;
}
.pack-card:hover { background: rgba(255,255,255,.12); transform: translateY(-4px); }
.pack-card b { display: block; font-size: 18.5px; font-weight: 800; margin-bottom: 8px; }
.pack-card b span {
  display: block; font-size: 13px; font-weight: 600; color: var(--gold);
  text-transform: uppercase; letter-spacing: .06em; margin-top: 3px;
}
.pack-card p { font-size: 13.5px; color: rgba(255,255,255,.8); }

.logistics-strip {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
  margin-top: 40px; padding-top: 32px;
  border-top: 1px solid rgba(255,255,255,.18);
}
.ls-item span { display: block; font-size: 12.5px; text-transform: uppercase; letter-spacing: .08em; color: rgba(255,255,255,.65); margin-bottom: 5px; }
.ls-item b { font-size: 16.5px; font-weight: 700; color: #fff; }

/* ---------- About ---------- */
.about-grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: 64px; align-items: center; }
.about-visual svg { width: 100%; height: auto; max-width: 420px; margin: 0 auto; }
.about-copy h2 { font-size: clamp(26px, 3.2vw, 36px); font-weight: 800; line-height: 1.22; margin-bottom: 18px; }
.about-copy p { color: var(--muted); margin-bottom: 16px; font-size: 15.5px; }
.about-chips { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 22px; }
.about-chips span {
  font-size: 13px; font-weight: 700; color: var(--blue-700);
  background: var(--blue-50); border: 1px solid #cfe4f4;
  border-radius: 999px; padding: 8px 18px;
}

/* ---------- RFQ ---------- */
.rfq-wrap { display: grid; grid-template-columns: 1fr 1.1fr; gap: 60px; align-items: start; }
.rfq-copy h2 { font-size: clamp(26px, 3.2vw, 36px); font-weight: 800; line-height: 1.22; margin-bottom: 18px; }
.rfq-copy > p { color: var(--muted); font-size: 15.5px; margin-bottom: 26px; }
.contact-list { display: grid; gap: 16px; }
.contact-list li {
  display: flex; gap: 16px; align-items: baseline;
  background: #fff; border: 1px solid var(--line);
  border-radius: 12px; padding: 15px 20px;
}
.contact-list b { font-size: 12.5px; text-transform: uppercase; letter-spacing: .08em; color: var(--blue-700); min-width: 130px; }
.contact-list span { font-weight: 600; font-size: 14.5px; }

.rfq-form {
  background: #fff; border: 1px solid var(--line); border-radius: 18px;
  padding: 34px 32px; box-shadow: var(--shadow);
}
.rfq-form h3 { font-size: 21px; font-weight: 800; color: var(--blue-900); margin-bottom: 22px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.field { display: flex; flex-direction: column; gap: 7px; margin-bottom: 16px; }
.field label { font-size: 13px; font-weight: 700; color: var(--ink); }
.field input, .field select, .field textarea {
  font-family: inherit; font-size: 14.5px; color: var(--ink);
  border: 1.5px solid var(--line); border-radius: 10px;
  padding: 12px 14px; background: #fbfdff;
  transition: border-color .18s ease, box-shadow .18s ease;
  width: 100%;
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none; border-color: var(--blue-500);
  box-shadow: 0 0 0 3px rgba(18, 115, 196, .14); background: #fff;
}
.field textarea { resize: vertical; }
.field.error input, .field.error textarea { border-color: #d94545; }
.form-note { font-size: 12.5px; color: var(--muted); margin-top: 14px; text-align: center; }

/* ---------- Footer ---------- */
.site-footer { background: var(--blue-900); color: rgba(255,255,255,.85); }
.footer-grid {
  display: grid; grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
  gap: 44px; padding: 64px 0 44px;
}
.footer-logo .logo-text strong { color: #fff; }
.footer-logo .logo-text small { color: rgba(255,255,255,.7); }
.footer-brand > p { font-size: 14px; margin-top: 16px; max-width: 40ch; }
.footer-col { display: flex; flex-direction: column; gap: 11px; }
.footer-col h4 {
  color: #fff; font-size: 15px; font-weight: 700; margin-bottom: 6px;
  padding-bottom: 10px; border-bottom: 1px solid rgba(255,255,255,.18);
}
.footer-col a, .footer-col span { font-size: 14px; color: rgba(255,255,255,.75); }
.footer-col a:hover { color: var(--gold); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.14); padding: 20px 0; }
.footer-bottom .container {
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
}
.footer-bottom p { font-size: 13px; color: rgba(255,255,255,.6); }

/* ---------- Reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .6s ease, transform .6s ease; }
.reveal.visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------- Responsive ---------- */
@media (max-width: 1080px) {
  .product-grid { grid-template-columns: repeat(2, 1fr); }
  .pack-grid { grid-template-columns: repeat(2, 1fr); }
  .app-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-inner { grid-template-columns: 1fr; gap: 40px; padding: 64px 0 110px; }
  .hero-card { max-width: 560px; }
  .main-nav { display: none; }
}

@media (max-width: 860px) {
  .quality-grid, .about-grid, .rfq-wrap { grid-template-columns: 1fr; gap: 40px; }
  .logistics-strip { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 640px) {
  .section { padding: 64px 0; }
  .product-grid, .app-grid, .pack-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .trust-inner { grid-template-columns: repeat(2, 1fr); gap: 14px; padding: 18px 0; }
  .trust-item { justify-content: flex-start; }
  .header-inner { height: 64px; gap: 14px; }
  .header-actions .btn-sm { display: none; }
  .nav-toggle { display: flex; }
  .main-nav {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    flex-direction: column; gap: 4px; padding: 18px 5%;
    box-shadow: var(--shadow-lg);
  }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 12px 6px; font-size: 16px; }
  .cert-wall { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom .container { flex-direction: column; }
}

/* ---------- Print (spec sheet style) ---------- */
@media print {
  .site-header, .hero-cta, .rfq-form, .trust-bar { display: none; }
  .section { padding: 20px 0; }
}