/* ========== Header ========== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.site-header.is-scrolled {
  border-bottom-color: var(--color-line);
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  height: var(--header-h);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

.brand-mark {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--color-primary);
  color: #fff;
  display: grid;
  place-items: center;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.85rem;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.98rem;
}

.brand-sub {
  font-size: 0.72rem;
  color: var(--color-muted);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.lang-toggle {
  display: inline-flex;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-full);
  overflow: hidden;
  background: var(--color-bg);
}

.lang-toggle button {
  border: 0;
  background: transparent;
  padding: 7px 12px;
  cursor: pointer;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--color-ink-soft);
}

.lang-toggle button[aria-pressed="true"] {
  background: var(--color-ink);
  color: #fff;
}

.nav-toggle {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  background: #fff;
  cursor: pointer;
}

.nav-toggle-bars {
  width: 18px;
  height: 12px;
  position: relative;
}

.nav-toggle-bars span {
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-ink);
  border-radius: 2px;
  transition: var(--transition);
}

.nav-toggle-bars span:nth-child(1) { top: 0; }
.nav-toggle-bars span:nth-child(2) { top: 5px; }
.nav-toggle-bars span:nth-child(3) { top: 10px; }

.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(1) {
  top: 5px;
  transform: rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(3) {
  top: 5px;
  transform: rotate(-45deg);
}

.main-nav {
  position: fixed;
  inset: var(--header-h) 0 0 0;
  background: #fff;
  transform: translateX(100%);
  visibility: hidden;
  transition: transform 0.3s var(--ease), visibility 0s linear 0.3s;
  overflow-y: auto;
  z-index: 90;
}

.main-nav.is-open {
  transform: none;
  visibility: visible;
  transition: transform 0.3s var(--ease);
}

.main-nav ul {
  list-style: none;
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.main-nav a {
  display: block;
  padding: 14px 4px;
  font-weight: 600;
  font-size: 1.15rem;
  border-bottom: 1px solid var(--color-line);
}

.main-nav .nav-cta-mobile {
  margin-top: 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.nav-overlay {
  position: fixed;
  inset: var(--header-h) 0 0 0;
  background: rgba(21, 24, 33, 0.4);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
  z-index: 80;
}

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

.header-actions .header-cta-desktop {
  display: none !important;
}

@media (min-width: 980px) {
  .nav-toggle,
  .nav-overlay,
  .main-nav .nav-cta-mobile {
    display: none;
  }

  .main-nav {
    position: static;
    inset: auto;
    transform: none;
    visibility: visible;
    background: transparent;
    overflow: visible;
    flex: 1;
  }

  .main-nav ul {
    flex-direction: row;
    align-items: center;
    justify-content: center;
    padding: 0;
    gap: 28px;
  }

  .main-nav a {
    padding: 6px 0;
    font-size: 0.92rem;
    border: 0;
    color: var(--color-ink-soft);
    transition: color var(--transition);
  }

  .main-nav a:hover,
  .main-nav a.is-active {
    color: var(--color-ink);
  }

  .header-inner {
    gap: 28px;
  }

  .header-actions .header-cta-desktop {
    display: inline-flex !important;
  }
}

/* ========== Footer ========== */
.site-footer {
  background: var(--color-bg-dark);
  color: #a8b0c0;
  padding: 64px 0 28px;
  font-size: 0.92rem;
}

.footer-grid {
  display: grid;
  gap: 36px;
  margin-bottom: 40px;
}

@media (min-width: 800px) {
  .footer-grid {
    grid-template-columns: 1.4fr 1fr 1fr 1fr;
  }
}

.footer-brand .brand-name {
  color: #fff;
  font-size: 1.1rem;
  margin-bottom: 10px;
  display: block;
}

.footer-grid h4 {
  color: #fff;
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 16px;
  font-family: var(--font-body);
  font-weight: 700;
}

.footer-grid ul {
  list-style: none;
  display: grid;
  gap: 10px;
}

.footer-grid a:hover {
  color: #fff;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: space-between;
  font-size: 0.8rem;
}

/* ========== Back to top / WA float ========== */
.back-to-top {
  position: fixed;
  right: 20px;
  bottom: 90px;
  z-index: 70;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: 0;
  background: var(--color-ink);
  color: #fff;
  cursor: pointer;
  display: grid;
  place-items: center;
  opacity: 0;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity var(--transition), transform var(--transition);
  box-shadow: var(--shadow-md);
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: none;
}

.wa-float {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 70;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--color-success);
  display: grid;
  place-items: center;
  box-shadow: 0 8px 24px rgba(37, 211, 102, 0.4);
  transition: transform var(--transition);
}

.wa-float:hover {
  transform: scale(1.06);
}

.wa-float svg {
  width: 28px;
  height: 28px;
  fill: #fff;
}