/* ================ HEADER ================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-header);
  height: var(--header-h);
  display: flex;
  align-items: center;
  background: linear-gradient(
    to bottom,
    rgba(251, 249, 244, 0.55),
    rgba(251, 249, 244, 0)
  );
  transition:
    background-color var(--transition-base),
    height var(--transition-base),
    border-color var(--transition-base),
    box-shadow var(--transition-base);
  border-bottom: 1px solid transparent;
}

.site-header.is-scrolled,
.site-header.is-solid {
  height: var(--header-h-scrolled);
  background: linear-gradient(
    180deg,
    rgba(26, 21, 38, 0.92) 0%,
    rgba(20, 16, 28, 0.92) 100%
  );
  backdrop-filter: blur(24px) saturate(1.4);
  -webkit-backdrop-filter: blur(24px) saturate(1.4);
  border-bottom: 1px solid rgba(168, 123, 30, 0.22);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.04),
    0 12px 36px -18px rgba(10, 8, 18, 0.55);
}

.header-inner {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
}

.site-logo {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
}

.site-logo img {
  height: 62px;
  width: auto;
  image-rendering: auto;
  filter: drop-shadow(0 1px 0px rgba(0, 0, 0, 0.6));
  transition:
    height var(--transition-base),
    filter var(--transition-base);
}
.footer-brand img {
  filter: drop-shadow(0 1px 0px rgba(0, 0, 0, 0.6));
  transition:
    height var(--transition-base),
    filter var(--transition-base);
}

.site-header.is-scrolled .site-logo img {
  height: 44px;
}

.site-logo .logo-scrolled {
  display: none;
}
.site-header.is-scrolled .site-logo .logo-rest,
.site-header.is-solid .site-logo .logo-rest {
  display: none;
}
.site-header.is-scrolled .site-logo .logo-scrolled,
.site-header.is-solid .site-logo .logo-scrolled {
  display: inline-block;
}

.primary-nav {
  display: flex;
  gap: clamp(1rem, 2vw, 2rem);
  align-items: center;
}

.primary-nav a {
  position: relative;
  font-size: var(--fs-small);
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--ivory-dim);
  padding: var(--space-2) 0;
  transition: color var(--transition-fast);
}
.is-scrolled .primary-nav a {
  color: var(--ink-600);
}

html[data-lang="zh"] .primary-nav a {
  letter-spacing: 0.12em;
  font-family: var(--font-serif-zh);
}

.primary-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 1.5px;
  background: linear-gradient(90deg, var(--gold-300), var(--gold-400));
  border-radius: 2px;
  box-shadow: 0 0 8px rgba(214, 172, 73, 0.5);
  transition: width var(--transition-base);
}

.primary-nav a:hover,
.primary-nav a[aria-current="page"] {
  color: var(--gold-300);
}

.primary-nav a:hover::after,
.primary-nav a[aria-current="page"]::after {
  width: 100%;
}

.header-utility {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

/* Language toggle */
.lang-toggle {
  display: inline-flex;
  align-items: center;
  padding: 4px;
  border: 1px solid rgba(214, 172, 73, 0.18);
  border-radius: 999px;
  gap: 2px;
  background: rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(14px) saturate(1.3);
  -webkit-backdrop-filter: blur(14px) saturate(1.3);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.08);
}

.lang-toggle button {
  font-size: var(--fs-micro);
  letter-spacing: var(--tracking-wide);
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 999px;
  transition:
    color var(--transition-fast),
    background-color var(--transition-fast),
    box-shadow var(--transition-fast);
  text-transform: uppercase;
}
.is-scrolled .lang-toggle button {
  color: var(--ink-600);
}
.lang-toggle button[aria-pressed="true"] {
  background: var(--gold-gradient);
  color: var(--ink-deeper);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.35),
    0 2px 10px -2px rgba(214, 172, 73, 0.45);
}

.lang-toggle button:not([aria-pressed="true"]):hover {
  color: var(--ink-900);
  background: rgba(255, 255, 255, 0.05);
}

/* Mobile menu */
.menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  position: relative;
}

.menu-toggle span {
  width: 22px;
  height: 2px;
  background: rgba(26, 21, 38, 0.88);
  position: relative;
  transition: background var(--transition-fast);
}
.is-scrolled .menu-toggle span {
  background: rgba(251, 249, 244, 0.88);
}

.menu-toggle span::before,
.menu-toggle span::after {
  content: "";
  position: absolute;
  left: 0;
  width: 22px;
  height: 2px;
  background: rgba(26, 21, 38, 0.88);
  transition:
    transform var(--transition-base),
    top var(--transition-base);
}
.is-scrolled .menu-toggle span::before,
.is-scrolled .menu-toggle span::after {
  background: rgba(251, 249, 244, 0.88);
}

.menu-toggle span::before {
  top: -7px;
}
.menu-toggle span::after {
  top: 7px;
}

.menu-toggle[aria-expanded="true"] span {
  background: transparent;
}
.menu-toggle[aria-expanded="true"] span::before {
  top: 0;
  transform: rotate(45deg);
}
.menu-toggle[aria-expanded="true"] span::after {
  top: 0;
  transform: rotate(-45deg);
}

.mobile-nav {
  position: fixed;
  inset: 0;
  background: rgba(251, 249, 244, 0.98);
  backdrop-filter: blur(20px);
  z-index: calc(var(--z-header) - 1);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-6);
  padding: var(--header-h) var(--container-pad) var(--space-8);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base);
}

.mobile-nav.is-open {
  opacity: 1;
  pointer-events: auto;
}

.mobile-nav a {
  font-family: var(--font-serif-en);
  font-size: clamp(1.5rem, 5vw, 2.25rem);
  color: var(--ivory);
  font-weight: 400;
  letter-spacing: 0.005em;
}

html[data-lang="zh"] .mobile-nav a {
  font-family: var(--font-serif-zh);
  font-weight: 500;
}

@media (max-width: 900px) {
  .primary-nav {
    display: none;
  }
  .menu-toggle {
    display: inline-flex;
  }
}

/* ================ BUTTONS ================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 14px 28px;
  font-family: var(--font-sans-en);
  font-size: var(--fs-small);
  font-weight: 500;
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  border-radius: var(--radius-sm);
  transition: all var(--transition-base);
  cursor: pointer;
  border: 1px solid transparent;
}

html[data-lang="zh"] .btn {
  font-family: var(--font-serif-zh);
  letter-spacing: 0.12em;
  text-transform: none;
}

.btn--gold {
  background: var(--gold-gradient);
  color: var(--ink-deep);
  box-shadow:
    0 1px 0 rgba(255, 255, 255, 0.35) inset,
    0 4px 14px -6px rgba(168, 123, 30, 0.45);
}

.btn--gold:hover {
  transform: translateY(-1px);
  box-shadow:
    0 1px 0 rgba(255, 255, 255, 0.4) inset,
    var(--shadow-gold);
  color: var(--ink-deeper);
}

.btn--ghost {
  color: var(--ivory-dim);
  border-color: rgba(168, 123, 30, 0.45);
  background: rgba(255, 255, 255, 0.4);
}

.btn--ghost:hover {
  color: var(--gold-600);
  border-color: var(--gold-500);
  background: rgba(255, 255, 255, 0.7);
}

.btn .arrow {
  transition: transform var(--transition-base);
}

.btn:hover .arrow {
  transform: translateX(4px);
}

/* ================ CARDS ================ */
.card {
  background: var(--ink-800);
  border: 1px solid rgba(28, 25, 22, 0.06);
  padding: var(--space-6);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition:
    border-color var(--transition-base),
    transform var(--transition-base),
    background-color var(--transition-base),
    box-shadow var(--transition-base);
  position: relative;
  overflow: hidden;
}

.card:hover {
  border-color: rgba(168, 123, 30, 0.42);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--gold-gradient);
  transition: width var(--transition-slow);
}

.card:hover::before {
  width: 100%;
}

.card-eyebrow {
  font-size: var(--fs-micro);
  letter-spacing: var(--tracking-widest);
  text-transform: uppercase;
  color: var(--gold-600);
  font-weight: 600;
}

.card-title {
  font-family: var(--font-serif-en);
  font-size: var(--fs-h3);
  font-weight: 500;
  margin-top: var(--space-3);
  color: var(--ivory);
}

html[data-lang="zh"] .card-title {
  font-family: var(--font-serif-zh);
  font-weight: 600;
}

.card-body {
  margin-top: var(--space-3);
  color: var(--warm-grey);
  font-size: var(--fs-small);
  line-height: var(--lh-relaxed);
}

/* ================ FOOTER ================ */
.site-footer {
  background: var(--ink-950);
  padding: var(--space-9) 0 var(--space-6);
  border-top: var(--hairline);
  margin-top: var(--space-9);
  position: relative;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: min(120px, 30%);
  height: 1px;
  background: var(--gold-gradient);
  opacity: 0.7;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-8);
}

@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 560px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

.footer-brand img {
  height: 56px;
  width: auto;
  margin-bottom: var(--space-5);
}

.footer-tagline {
  color: var(--warm-grey);
  font-size: var(--fs-small);
  max-width: 32ch;
  line-height: var(--lh-relaxed);
}

.footer-col h4 {
  font-size: var(--fs-micro);
  letter-spacing: var(--tracking-widest);
  text-transform: uppercase;
  color: var(--gold-600);
  margin-bottom: var(--space-5);
  font-weight: 600;
}

html[data-lang="zh"] .footer-col h4 {
  letter-spacing: var(--tracking-wider);
}

.footer-col a,
.footer-col span {
  display: block;
  color: var(--warm-grey);
  font-size: var(--fs-small);
  padding: var(--space-2) 0;
  line-height: 1.5;
}

.footer-col a:hover {
  color: var(--gold-600);
}

.footer-bottom {
  margin-top: var(--space-8);
  padding-top: var(--space-5);
  border-top: var(--divider-ink);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
  color: var(--warm-grey-dim);
  font-size: var(--fs-micro);
  letter-spacing: var(--tracking-wide);
}