/* Header-specific styles for English Learning Hub */

.elh-header {
  backdrop-filter: blur(20px);
}

.elh-header__brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

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

.elh-header__logo-mark {
  width: 2.4rem;
  height: 2.4rem;
  border-radius: var(--radius-xl);
  background: conic-gradient(from 140deg, #6366f1, #22c55e, #0ea5e9, #6366f1);
  box-shadow: 0 0 0 2px rgba(15, 23, 42, 0.95), 0 10px 30px rgba(15, 23, 42, 0.7);
  position: relative;
}

.elh-header__logo-mark::after {
  content: "";
  position: absolute;
  inset: 4px;
  border-radius: inherit;
  background: radial-gradient(circle at 30% 20%, rgba(249, 250, 251, 0.9) 0, transparent 45%),
    radial-gradient(circle at 70% 80%, rgba(191, 219, 254, 0.35) 0, transparent 55%),
    #020617;
}

.elh-header__identity {
  display: flex;
  flex-direction: column;
}

.elh-header__site-name {
  font-family: var(--font-display);
  font-size: var(--font-size-lg);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-gray-50);
}

.elh-header__site-tagline {
  font-size: var(--font-size-xs);
  color: var(--color-text-soft);
}

/* Navigation layout */

.elh-header__nav {
  display: flex;
}

.elh-header__nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  list-style: none;
  margin: 0;
  padding: 0;
}

.elh-header__nav-link {
  position: relative;
  font-size: var(--font-size-sm);
  text-decoration: none;
}

.elh-header__nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -0.2rem;
  height: 2px;
  border-radius: var(--radius-full);
  background: linear-gradient(90deg, var(--color-primary), var(--color-success));
  transform-origin: center;
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.elh-header__nav-link:hover::after,
.elh-header__nav-link:focus-visible::after,
.elh-header__nav-link--active::after {
  transform: scaleX(1);
}

.elh-header__nav-item--highlight .elh-header__nav-link--cta {
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-full);
  border: 1px solid rgba(129, 140, 248, 0.8);
  background: radial-gradient(circle at 0 0, rgba(129, 140, 248, 0.25) 0, transparent 45%),
    rgba(15, 23, 42, 0.85);
  box-shadow: var(--shadow-soft-sm);
}

.elh-header__nav-item--highlight .elh-header__nav-link--cta::after {
  display: none;
}

.elh-header__nav-item--highlight .elh-header__nav-link--cta:hover,
.elh-header__nav-item--highlight .elh-header__nav-link--cta:focus-visible {
  border-color: rgba(129, 140, 248, 1);
  background: radial-gradient(circle at 0 0, rgba(129, 140, 248, 0.45) 0, transparent 55%),
    rgba(15, 23, 42, 0.95);
}

/* Mobile menu toggle */

.elh-header__menu-toggle {
  display: none;
  align-items: center;
  gap: var(--space-2);
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border-strong);
  background: rgba(15, 23, 42, 0.9);
  color: var(--color-gray-100);
}

.elh-header__menu-toggle-inner {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.22rem;
}

.elh-header__menu-bar {
  width: 1.1rem;
  height: 0.12rem;
  border-radius: var(--radius-full);
  background: var(--color-gray-200);
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.elh-header__menu-label {
  font-size: var(--font-size-xs);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

/* Mobile layout */

@media (max-width: 768px) {
  .site-nav {
    align-items: center;
  }

  .elh-header__menu-toggle {
    display: inline-flex;
  }

  .elh-header__nav {
    position: absolute;
    inset-inline: 0;
    top: var(--nav-height);
    background: radial-gradient(circle at top, rgba(15, 23, 42, 0.98) 0, #020617 55%);
    border-bottom: 1px solid rgba(31, 41, 55, 0.95);
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: max-height var(--transition-slow), opacity var(--transition-base), visibility var(--transition-base), transform var(--transition-base);
  }

  .elh-header__nav-list {
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-4);
    gap: var(--space-3);
  }

  .elh-header__nav-link {
    width: 100%;
    padding-block: 0.15rem;
  }

  .elh-header__nav-link::after {
    bottom: -0.35rem;
  }

  .elh-header__nav--open {
    max-height: 320px;
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .elh-header__menu-toggle--active .elh-header__menu-bar:nth-child(1) {
    transform: translateY(0.34rem) rotate(45deg);
  }

  .elh-header__menu-toggle--active .elh-header__menu-bar:nth-child(2) {
    opacity: 0;
  }

  .elh-header__menu-toggle--active .elh-header__menu-bar:nth-child(3) {
    transform: translateY(-0.34rem) rotate(-45deg);
  }
}

/* Medium+ screens */

@media (min-width: 769px) {
  .elh-header__nav {
    position: static;
    opacity: 1;
    visibility: visible;
    max-height: none;
    transform: none;
  }
}

/* Focus styles refinement for header-only elements */

.elh-header__nav-link:focus-visible,
.elh-header__menu-toggle:focus-visible,
.elh-header__logo-link:focus-visible {
  outline: none;
  box-shadow: var(--shadow-focus);
  border-radius: var(--radius-full);
}