/* ==========================================================================
   MODO — 15. Header
   Transparente sobre el hero; al hacer scroll toma fondo azul con blur.
   ========================================================================== */

.header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: var(--z-header);
  height: var(--header-h);
  display: flex;
  align-items: center;
  background-color: transparent;
  border-bottom: 1px solid transparent;
  transition:
    background-color var(--t-med) var(--ease-soft),
    border-color var(--t-med) var(--ease-soft),
    height var(--t-med) var(--ease-soft);
}

.header.is-stuck {
  height: 72px;
  background-color: rgba(0, 41, 103, 0.86);
  border-bottom-color: var(--borde-tenue);
  -webkit-backdrop-filter: blur(14px);
          backdrop-filter: blur(14px);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  width: 100%;
}

/* --- Logo --- */
.header__logo {
  color: var(--blanco);
  flex: none;
  transition: opacity var(--t-fast) var(--ease-soft);
}
.header__logo:hover { opacity: 0.75; }
.header__logo .brand-mark { width: 116px; }

/* --- Navegación desktop --- */
.nav {
  display: flex;
  align-items: center;
  gap: clamp(0.875rem, 1.75vw, 1.75rem);
  margin-left: auto;
}

.nav__link {
  position: relative;
  font-size: var(--fs-nav);
  font-weight: 500;
  letter-spacing: 0.012em;
  color: var(--texto-tenue);
  padding-block: 0.4rem;
  white-space: nowrap;
  transition: color var(--t-fast) var(--ease-soft);
}
.nav__link:hover,
.nav__link:focus-visible { color: var(--blanco); }

/* Subrayado lima que crece desde la izquierda */
.nav__link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background-color: var(--lima);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--t-med) var(--ease);
}
.nav__link:hover::after,
.nav__link:focus-visible::after { transform: scaleX(1); }

.header__cta { flex: none; margin-left: clamp(0.75rem, 1.6vw, 1.5rem); }

/* --- Botón hamburguesa --- */
.burger {
  display: none;
  width: 44px;
  height: 44px;
  margin-right: -10px;
  padding: 0;
  place-items: center;
}
.burger__box {
  position: relative;
  width: 24px;
  height: 14px;
}
.burger__box span {
  position: absolute;
  left: 0;
  width: 100%;
  height: 1.5px;
  background-color: var(--blanco);
  transition: transform var(--t-med) var(--ease), opacity var(--t-fast) linear;
}
.burger__box span:nth-child(1) { top: 0; }
.burger__box span:nth-child(2) { top: 50%; transform: translateY(-50%); }
.burger__box span:nth-child(3) { bottom: 0; }

.burger[aria-expanded='true'] .burger__box span:nth-child(1) {
  transform: translateY(6.25px) rotate(45deg);
}
.burger[aria-expanded='true'] .burger__box span:nth-child(2) { opacity: 0; }
.burger[aria-expanded='true'] .burger__box span:nth-child(3) {
  transform: translateY(-6.25px) rotate(-45deg);
}

/* ==========================================================================
   Menú mobile — pantalla completa
   ========================================================================== */
.menu {
  position: fixed;
  inset: 0;
  z-index: var(--z-menu);
  display: flex;
  flex-direction: column;
  padding: calc(var(--header-h-sm) + 2rem) var(--gutter) 2.5rem;
  background-color: var(--azul-oscuro);
  overflow-y: auto;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition:
    opacity var(--t-med) var(--ease-soft),
    transform var(--t-med) var(--ease-soft),
    visibility 0s linear var(--t-med);
}
.menu.is-open {
  opacity: 1;
  visibility: visible;
  transform: none;
  transition-delay: 0s;
}

.menu__list {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  margin-top: auto;
  margin-bottom: auto;
}

.menu__link {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 7.5vw, 2.5rem);
  font-weight: 600;
  letter-spacing: var(--ls-tight);
  line-height: 1.5;
  color: var(--blanco);
  opacity: 0;
  transform: translateY(14px);
}
.menu.is-open .menu__link {
  opacity: 1;
  transform: none;
  transition:
    opacity var(--t-med) var(--ease) var(--i-delay, 0ms),
    transform var(--t-med) var(--ease) var(--i-delay, 0ms);
}
.menu__link:active { color: var(--lima); }

.menu__cta {
  justify-content: center;
  width: 100%;
  margin-top: 2rem;
}

.menu__meta {
  margin-top: 2.25rem;
  font-size: var(--fs-micro);
  letter-spacing: var(--ls-wide);
  text-transform: uppercase;
  color: var(--texto-tenue);
}

/* ==========================================================================
   Responsive
   ========================================================================== */

/* Con 8 links, por debajo de 1100px la nav horizontal ya se comprime mal */
@media (max-width: 1199px) {
  .nav, .header__cta { display: none; }
  .burger { display: grid; }
  .header { height: var(--header-h-sm); }
  .header.is-stuck { height: var(--header-h-sm); }
  .header__logo .brand-mark { width: 96px; }
}

@media (min-width: 1200px) {
  .menu { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  .menu__link { opacity: 1; transform: none; }
}