/* ==========================================================================
   LUMINA EUROPE - LAYOUT STYLES
   ========================================================================== */

/* Main Page Sections */
.page-section {
  padding-top: clamp(4rem, 7vw, 6.5rem);
  padding-bottom: clamp(4rem, 7vw, 6.5rem);
  position: relative;
}

.page-section.bg-subtle {
  background-color: var(--color-bg-subtle);
  border-top: 1px solid var(--color-border-hairline);
  border-bottom: 1px solid var(--color-border-hairline);
}

.page-section.bg-navy {
  background: linear-gradient(180deg, #07162C 0%, #0C2340 100%);
  color: #FFFFFF;
}

.page-section.bg-navy h2,
.page-section.bg-navy h3,
.page-section.bg-navy h4 {
  color: #FFFFFF;
}

.page-section.bg-navy .section-subtitle {
  color: #94A3B8;
}

/* Header & Sticky Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border-hairline);
  transition: all var(--transition-fast);
}

.site-header.is-scrolled {
  box-shadow: 0 4px 20px -2px rgba(12, 35, 64, 0.08);
  background-color: rgba(255, 255, 255, 0.98);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 82px;
  transition: height var(--transition-fast);
}

.site-header.is-scrolled .header-inner {
  height: 72px;
}

/* Brand Link */
.brand-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
}

.brand-logo-img {
  height: 48px;
  width: auto;
  transition: transform var(--transition-fast);
}

.brand-link:hover .brand-logo-img {
  transform: scale(1.02);
}

/* Nav Menu */
.nav-menu {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 1.6vw, 1.75rem);
  list-style: none;
  white-space: nowrap;
}

.nav-link {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  text-decoration: none;
  padding: 0.5rem 0;
  position: relative;
  transition: color var(--transition-fast);
  white-space: nowrap;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 2px;
  background-color: var(--color-cobalt-700);
  transition: width var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-cobalt-700);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

/* Header Action Buttons */
.header-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

@media (max-width: 768px) {
  .header-actions .btn {
    display: none;
  }
}

/* Mobile Menu Hamburger */
.mobile-nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--color-navy-900);
}

.mobile-nav-toggle svg {
  width: 26px;
  height: 26px;
}

@media (max-width: 1024px) {
  .nav-menu {
    position: fixed;
    top: 82px;
    left: 0;
    width: 100%;
    background-color: #FFFFFF;
    border-bottom: 2px solid var(--color-border-hairline);
    flex-direction: column;
    align-items: stretch;
    padding: 1.5rem var(--container-padding);
    gap: 1.25rem;
    box-shadow: var(--shadow-lg);
    display: none;
  }

  .nav-menu.is-open {
    display: flex;
  }

  .nav-link {
    font-size: 1.05rem;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--color-border-hairline);
  }

  .nav-link::after {
    display: none;
  }

  .mobile-nav-toggle {
    display: block;
  }
}

/* Academic Pattern Backgrounds */
.bg-grid-pattern {
  background-image: radial-gradient(var(--color-border-subtle) 1px, transparent 1px);
  background-size: 32px 32px;
}

.bg-constellation {
  position: absolute;
  top: 0;
  right: 0;
  width: 600px;
  height: 600px;
  pointer-events: none;
  opacity: 0.45;
  background: radial-gradient(circle at 75% 25%, rgba(2, 132, 199, 0.12) 0%, rgba(29, 78, 216, 0.05) 45%, transparent 70%);
}