/* ============================================================
   TopOptimization 拓普优化 — Premium Cross-Border E-Commerce
   Dark editorial theme · champagne gold accents
   ============================================================ */

:root {
  --bg:        #0a0a0c;
  --bg-soft:   #101014;
  --surface:   #15151a;
  --surface-2: #1a1a20;
  --line:      rgba(255, 255, 255, 0.08);
  --line-gold: rgba(201, 162, 94, 0.35);
  --gold:      #c9a25e;
  --gold-hi:   #e8cf9a;
  --gold-lo:   #a8813f;
  --text:      #f2efe9;
  --muted:     #a09c93;
  --serif:     'Playfair Display', 'Noto Serif SC', Georgia, 'Songti SC', serif;
  --sans:      'Inter', 'Noto Sans SC', -apple-system, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --header-h:  74px;
  --ease:      cubic-bezier(.22, .61, .36, 1);
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-weight: 300;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

::selection { background: rgba(201, 162, 94, .35); }

img { max-width: 100%; display: block; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 28px; }

section[id] { scroll-margin-top: var(--header-h); }

/* ---------- Typography helpers ---------- */
.eyebrow {
  font-size: 12px;
  letter-spacing: .32em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 18px;
  font-weight: 500;
}

.gold-text {
  background: linear-gradient(120deg, var(--gold-hi) 0%, var(--gold) 55%, var(--gold-lo) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-style: italic;
}

.gold-rule {
  display: block;
  width: 64px;
  height: 1px;
  background: linear-gradient(90deg, var(--gold), transparent);
  margin-top: 22px;
}

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--header-h);
  z-index: 100;
  transition: background .4s var(--ease), border-color .4s var(--ease), backdrop-filter .4s;
  border-bottom: 1px solid transparent;
}

.site-header.scrolled {
  background: rgba(10, 10, 12, .82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom-color: var(--line);
}

.header-inner {
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 12px;
  text-decoration: none;
  color: var(--text);
  white-space: nowrap;
}

.brand-en {
  font-family: var(--serif);
  font-size: 21px;
  font-weight: 600;
  letter-spacing: .22em;
}

.brand-divider {
  width: 1px;
  height: 16px;
  background: var(--line-gold);
  align-self: center;
}

.brand-zh {
  font-family: var(--serif);
  font-size: 15px;
  color: var(--gold);
  letter-spacing: .18em;
}

.main-nav { display: flex; gap: 34px; }

.main-nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 13.5px;
  letter-spacing: .06em;
  font-weight: 400;
  position: relative;
  padding: 6px 0;
  transition: color .3s;
}

.main-nav a::after {
  content: '';
  position: absolute;
  left: 0; bottom: 0;
  width: 0; height: 1px;
  background: var(--gold);
  transition: width .35s var(--ease);
}

.main-nav a:hover { color: var(--text); }
.main-nav a:hover::after { width: 100%; }

.header-actions { display: flex; align-items: center; gap: 18px; }

.lang-switch {
  display: flex;
  border: 1px solid var(--line);
  border-radius: 999px;
  overflow: hidden;
}

.lang-btn {
  background: transparent;
  border: 0;
  color: var(--muted);
  font-family: var(--sans);
  font-size: 12px;
  letter-spacing: .08em;
  padding: 7px 16px;
  cursor: pointer;
  transition: all .3s;
}

.lang-btn:hover { color: var(--text); }

.lang-btn.active {
  background: linear-gradient(120deg, var(--gold-hi), var(--gold-lo));
  color: #0a0a0c;
  font-weight: 600;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  width: 22px; height: 1.5px;
  background: var(--text);
  transition: all .3s;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 96vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: url('../img/hero.png') center / cover no-repeat;
  transform: scale(1.04);
  animation: heroDrift 22s var(--ease) infinite alternate;
}

@keyframes heroDrift {
  from { transform: scale(1.04) translateX(0); }
  to   { transform: scale(1.10) translateX(-24px); }
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(10,10,12,.94) 0%, rgba(10,10,12,.78) 42%, rgba(10,10,12,.28) 100%),
    linear-gradient(180deg, rgba(10,10,12,.55) 0%, transparent 30%, rgba(10,10,12,.85) 100%);
}

.hero-content { position: relative; z-index: 2; max-width: 860px; }

.hero-title {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(40px, 5.6vw, 74px);
  line-height: 1.14;
  letter-spacing: .01em;
  margin-bottom: 26px;
}

.hero-title em { display: block; font-weight: 500; }

.hero-sub {
  max-width: 560px;
  color: var(--muted);
  font-size: 17px;
  margin-bottom: 42px;
}

.hero-cta { display: flex; gap: 18px; flex-wrap: wrap; }

.btn {
  display: inline-block;
  padding: 15px 36px;
  font-size: 13px;
  letter-spacing: .18em;
  text-transform: uppercase;
  text-decoration: none;
  font-weight: 500;
  border: 1px solid transparent;
  cursor: pointer;
  font-family: var(--sans);
  transition: all .35s var(--ease);
}

.btn-gold {
  background: linear-gradient(120deg, var(--gold-hi), var(--gold) 50%, var(--gold-lo));
  color: #0a0a0c;
}

.btn-gold:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 34px -12px rgba(201, 162, 94, .55);
}

.btn-ghost {
  border-color: rgba(255,255,255,.28);
  color: var(--text);
}

.btn-ghost:hover {
  border-color: var(--gold);
  color: var(--gold-hi);
  transform: translateY(-2px);
}

.hero-scroll {
  position: absolute;
  left: 50%;
  bottom: 34px;
  width: 1px;
  height: 56px;
  background: linear-gradient(180deg, var(--gold), transparent);
  opacity: .7;
  animation: scrollPulse 2.4s ease-in-out infinite;
}

@keyframes scrollPulse {
  0%, 100% { transform: scaleY(.4); transform-origin: top; opacity: .3; }
  50%      { transform: scaleY(1);  opacity: .8; }
}

/* ---------- Stats band ---------- */
.stats-band {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--bg-soft);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}

.stat {
  padding: 44px 20px;
  text-align: center;
  border-left: 1px solid var(--line);
}

.stat:first-child { border-left: 0; }

.stat-num {
  display: block;
  font-family: var(--serif);
  font-size: 46px;
  font-weight: 600;
  line-height: 1;
  margin-bottom: 10px;
}

.stat-num small { font-size: 24px; }

.stat-label {
  font-size: 12.5px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
}

/* ---------- Sections ---------- */
.section { padding: 120px 0; }

.section-alt { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }

.section-head { max-width: 720px; margin-bottom: 64px; }

.section-title {
  font-family: var(--serif);
  font-size: clamp(30px, 3.4vw, 44px);
  font-weight: 600;
  line-height: 1.2;
}

.section-sub { color: var(--muted); margin-top: 18px; }

/* ---------- About ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 72px;
  align-items: start;
}

.about-copy p { color: var(--muted); margin-bottom: 22px; }
.about-copy p:first-child {
  color: var(--text);
  font-size: 19px;
  font-weight: 300;
  line-height: 1.7;
}

.values { display: grid; gap: 18px; }

.value-card {
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 28px 30px;
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-rows: auto auto;
  column-gap: 22px;
  transition: border-color .35s, transform .35s var(--ease);
}

.value-card:hover { border-color: var(--line-gold); transform: translateX(6px); }

.value-num {
  grid-row: 1 / 3;
  font-family: var(--serif);
  font-size: 30px;
  color: var(--gold);
  opacity: .85;
  line-height: 1.2;
}

.value-card h3 { font-size: 16px; font-weight: 500; letter-spacing: .04em; margin-bottom: 8px; }
.value-card p  { font-size: 14px; color: var(--muted); }

/* ---------- Collections ---------- */
.collection-showcase {
  position: relative;
  margin-bottom: 56px;
  overflow: hidden;
  border: 1px solid var(--line);
}

.collection-showcase img {
  width: 100%;
  height: 460px;
  object-fit: cover;
  transition: transform 1.2s var(--ease);
}

.collection-showcase:hover img { transform: scale(1.03); }

.collection-caption {
  position: absolute;
  left: 0; bottom: 0;
  padding: 36px 42px;
  background: linear-gradient(180deg, transparent, rgba(10,10,12,.92));
  max-width: 640px;
}

.collection-caption h3 {
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 600;
  margin-bottom: 8px;
}

.collection-caption p { color: var(--muted); font-size: 14.5px; }

.category-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.category-card {
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 30px 28px;
  position: relative;
  overflow: hidden;
  transition: border-color .35s, transform .35s var(--ease);
}

.category-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 1px;
  background: linear-gradient(90deg, var(--gold), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .5s var(--ease);
}

.category-card:hover { border-color: var(--line-gold); transform: translateY(-4px); }
.category-card:hover::before { transform: scaleX(1); }

.category-card h3 { font-size: 17px; font-weight: 500; margin-bottom: 6px; }
.category-card .cat-en {
  font-size: 11px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--gold);
  display: block;
  margin-bottom: 14px;
}
.category-card p { font-size: 14px; color: var(--muted); }

/* ---------- Markets ---------- */
.market-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.market-card {
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 26px 28px;
  display: flex;
  align-items: center;
  gap: 20px;
  transition: border-color .35s, transform .35s var(--ease), background .35s;
}

.market-card:hover {
  border-color: var(--line-gold);
  background: var(--surface-2);
  transform: translateY(-3px);
}

.flag {
  width: 44px;
  height: 30px;
  border-radius: 3px;
  overflow: hidden;
  flex-shrink: 0;
  border: 1px solid rgba(255,255,255,.14);
  box-shadow: 0 4px 14px rgba(0,0,0,.4);
}

.flag svg { width: 100%; height: 100%; display: block; }

.market-info h3 { font-size: 16.5px; font-weight: 500; letter-spacing: .02em; }
.market-info .mkt-meta { font-size: 12.5px; color: var(--muted); letter-spacing: .05em; }
.market-info .mkt-site {
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--gold);
}

/* ---------- Supply chain ---------- */
.supply-showcase {
  position: relative;
  margin-bottom: 56px;
  border: 1px solid var(--line);
  overflow: hidden;
}

.supply-showcase img {
  width: 100%;
  height: 420px;
  object-fit: cover;
  filter: saturate(.9);
}

.supply-quote {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: flex-end;
  padding: 40px 46px;
  background: linear-gradient(180deg, transparent 30%, rgba(10,10,12,.9));
}

.supply-quote p {
  font-family: var(--serif);
  font-size: clamp(19px, 2.4vw, 27px);
  font-weight: 500;
  line-height: 1.5;
  max-width: 680px;
}

.supply-quote p::before {
  content: '“';
  color: var(--gold);
  font-size: 1.4em;
  margin-right: 6px;
}

.cap-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.cap-card {
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 32px 26px;
  transition: border-color .35s, transform .35s var(--ease);
}

.cap-card:hover { border-color: var(--line-gold); transform: translateY(-4px); }

.cap-icon {
  color: var(--gold);
  font-size: 20px;
  margin-bottom: 18px;
}

.cap-card h3 { font-size: 15.5px; font-weight: 500; margin-bottom: 10px; letter-spacing: .03em; }
.cap-card p  { font-size: 13.5px; color: var(--muted); }

/* ---------- Partners ---------- */
.partner-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.partner-card {
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 38px 32px;
  display: flex;
  flex-direction: column;
  transition: border-color .35s, transform .35s var(--ease);
}

.partner-card:hover { border-color: var(--line-gold); transform: translateY(-4px); }

.partner-card .p-tag {
  font-size: 11px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 16px;
}

.partner-card h3 {
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 600;
  margin-bottom: 12px;
}

.partner-card p { font-size: 14px; color: var(--muted); flex: 1; }

.partner-card .p-link {
  margin-top: 24px;
  color: var(--gold-hi);
  text-decoration: none;
  font-size: 12.5px;
  letter-spacing: .16em;
  text-transform: uppercase;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: gap .3s;
}

.partner-card .p-link:hover { gap: 14px; }

/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.3fr;
  gap: 64px;
  align-items: start;
}

.contact-item {
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
}

.contact-item h4 {
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--gold);
  font-weight: 500;
  margin-bottom: 8px;
}

.contact-item p { color: var(--muted); font-size: 15px; }
.contact-item a { color: var(--text); text-decoration: none; }
.contact-item a:hover { color: var(--gold-hi); }

.contact-form { display: grid; gap: 16px; }

.contact-form input,
.contact-form textarea {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--line);
  color: var(--text);
  font-family: var(--sans);
  font-size: 14.5px;
  padding: 15px 18px;
  transition: border-color .3s;
  resize: vertical;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--gold);
}

.contact-form input::placeholder,
.contact-form textarea::placeholder { color: #6d6a63; }

.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

.contact-form .btn { justify-self: start; border: 0; }

/* ---------- Footer ---------- */
.site-footer {
  background: #070709;
  border-top: 1px solid var(--line);
  padding-top: 72px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 56px;
}

.footer-brand p {
  color: var(--muted);
  font-size: 14px;
  margin-top: 18px;
  max-width: 300px;
}

.footer-col h4 {
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--gold);
  font-weight: 500;
  margin-bottom: 20px;
}

.footer-col a {
  display: block;
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  padding: 5px 0;
  transition: color .3s;
}

.footer-col a:hover { color: var(--gold-hi); }

.footer-col p { color: var(--muted); font-size: 14px; }

.footer-markets { display: flex; flex-wrap: wrap; gap: 6px 14px; }

.footer-markets span {
  color: var(--muted);
  font-size: 13px;
  letter-spacing: .04em;
}

.footer-bottom {
  border-top: 1px solid var(--line);
  padding: 22px 0;
}

.footer-bottom p {
  color: #6d6a63;
  font-size: 12.5px;
  letter-spacing: .04em;
  text-align: center;
}

/* ---------- Reveal animation ---------- */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
}

.reveal.visible { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .about-grid { grid-template-columns: 1fr; gap: 48px; }
  .cap-grid { grid-template-columns: repeat(2, 1fr); }
  .category-grid, .market-grid, .partner-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .contact-grid { grid-template-columns: 1fr; gap: 44px; }
}

@media (max-width: 768px) {
  .section { padding: 84px 0; }

  .main-nav {
    position: fixed;
    top: var(--header-h);
    left: 0; right: 0;
    flex-direction: column;
    gap: 0;
    background: rgba(10,10,12,.97);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--line);
    max-height: 0;
    overflow: hidden;
    transition: max-height .45s var(--ease);
  }

  .main-nav.open { max-height: 420px; }

  .main-nav a {
    padding: 16px 28px;
    border-top: 1px solid var(--line);
    font-size: 15px;
  }

  .main-nav a::after { display: none; }

  .nav-toggle { display: flex; }

  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .stat:nth-child(odd) { border-left: 0; }
  .stat:nth-child(n+3) { border-top: 1px solid var(--line); }

  .category-grid, .market-grid, .partner-grid, .cap-grid { grid-template-columns: 1fr; }

  .collection-showcase img { height: 320px; }
  .supply-showcase img { height: 300px; }
  .collection-caption { padding: 24px; }
  .supply-quote { padding: 24px; }

  .form-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 36px; }

  .hero { min-height: 88vh; }
  .hero-title { font-size: clamp(34px, 9vw, 48px); }

  .brand-zh { display: none; }
  .brand-divider { display: none; }
}