/* ==========================================================
   Encabezado y navegación
   ========================================================== */
.site-header {
  position: sticky;
  top: env(safe-area-inset-top, 0px);
  z-index: 30;
  background: var(--c-surface);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.site-header.is-scrolled {
  border-bottom-color: var(--c-line);
  box-shadow: 0 2px 12px rgba(43, 48, 36, 0.06);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  height: var(--header-h);
}

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

.brand__mark {
  width: auto;
  height: 38px;
  mix-blend-mode: multiply; /* el logo tiene fondo blanco */
}

.brand__name {
  font-family: var(--f-display);
  font-size: 1.2rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.site-nav {
  display: flex;
  gap: clamp(0.9rem, 0.5rem + 1.5vw, 2rem);
}

.site-nav a {
  position: relative;
  white-space: nowrap;
  padding-block: var(--space-2);
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--c-ink-soft);
  transition: color 0.2s var(--ease);
}

.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 2px;
  height: 1px;
  background: var(--c-rust);
  transform: scaleX(0);
  transition: transform 0.25s var(--ease);
}

.site-nav a:hover {
  color: var(--c-ink);
}

.site-nav a:hover::after {
  transform: scaleX(1);
}

@media (max-width: 640px) {
  .brand__name {
    display: none;
  }
}

@media (max-width: 400px) {
  .site-nav {
    gap: 0.75rem;
  }
  .site-nav a {
    letter-spacing: 0.1em;
  }
  .brand__mark {
    height: 32px;
  }
}