/* Header & Navigation Styles */

/* 5. Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 80px;
  background-color: rgba(255, 255, 255, 0.7); /* Translucent 70% */
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px); /* Safari support */
  z-index: 1000;
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  display: flex;
  align-items: center;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  position: relative; /* Context for mega menu positioning */
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  z-index: 1002;
  position: relative;
}

.logo img {
  height: 48px;
  width: auto;
}

.logo-text {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 1.25rem;
  color: var(--color-text-primary);
  letter-spacing: -0.03em;
}

/* --- Mobile Toggle --- */
.mobile-toggle {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  width: 24px;
  height: 18px;
  background: none;
  border: none;
  cursor: pointer;
  z-index: 1002;
  padding: 0;
}

.mobile-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-text-primary);
  border-radius: 2px;
  transition: all 0.3s ease;
}

body.mobile-open .mobile-toggle span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
body.mobile-open .mobile-toggle span:nth-child(2) { opacity: 0; }
body.mobile-open .mobile-toggle span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

/* --- Desktop Nav --- */
.nav {
  display: none;
}

/* --- Mobile Menu Overlay --- */
.mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  background-color: #FFFFFF;
  z-index: 1001;
  padding: 100px var(--spacing-sm) var(--spacing-md);
  transform: translateX(100%);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

body.mobile-open .mobile-menu {
  transform: translateX(0);
}

.mobile-nav-items {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  font-size: var(--text-lg);
  font-weight: 500;
}

.mobile-nav-link {
  color: var(--color-text-primary);
  border-bottom: 1px solid var(--color-border);
  padding-bottom: var(--spacing-sm);
}

.mobile-accordion-trigger {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  background: none;
  border: none;
  font-size: inherit;
  font-family: inherit;
  font-weight: inherit;
  color: var(--color-text-primary);
  cursor: pointer;
  padding-bottom: var(--spacing-sm);
  border-bottom: 1px solid var(--color-border);
}

.accordion-arrow {
  transition: transform 0.3s ease;
}

.mobile-accordion.active .accordion-arrow {
  transform: rotate(180deg);
}

.mobile-accordion-content {
  display: none;
  flex-direction: column;
  gap: var(--spacing-sm);
  padding-top: var(--spacing-sm);
  padding-left: var(--spacing-sm);
  background: rgba(0,0,0,0.02);
}

.mobile-accordion.active .mobile-accordion-content {
  display: flex;
}

.mobile-sub-link {
  font-size: var(--text-base);
  color: var(--color-text-secondary);
  padding: 8px 0;
}

.mobile-lang-switch {
  margin-top: var(--spacing-lg);
  display: flex;
  gap: var(--spacing-sm);
}

/* --- Desktop Styles (min-width: 900px) --- */
@media (min-width: 900px) {
  .mobile-toggle, .mobile-menu {
    display: none;
  }

  .header-inner {
    justify-content: flex-start;
  }

  .logo {
    margin-right: 8rem;
  }

  .nav {
    display: flex;
    align-items: center;
    width: 100%;
  }

  .nav-link {
    margin-left: 0;
    margin-right: 2rem;
    color: var(--color-text-secondary);
    font-size: var(--text-sm);
    font-weight: 600; /* Slightly bolder for IBM Plex Mono or Inter consistency */
    font-family: var(--font-mono);
    padding: 28px 0;
    position: relative;
    display: flex;
    align-items: center;
    height: 80px;
    background: none;
    border: none;
    cursor: pointer;
    transition: color 0.2s ease;
  }

  .nav-arrow {
    transition: transform 0.2s ease, opacity 0.2s ease;
  }
  
  /* Active Arrow State */
  .nav-group.active .nav-arrow {
    transform: rotate(180deg);
    opacity: 1 !important;
  }
  
  .nav-group {
    display: flex;
    align-items: center;
    height: 80px;
    margin-right: 2rem;
  }

  .nav-group .nav-link {
    margin-right: 0;
  }

  .nav-link:hover, .nav-group.active .nav-link {
    color: var(--color-text-primary);
  }

  .lang-switch {
    margin-left: auto;
    display: flex;
    gap: var(--spacing-xs);
  }

  .lang-btn {
    font-size: var(--text-xs);
    font-weight: 600;
    color: var(--color-text-tertiary);
    padding: 6px 10px;
    border-radius: 4px;
    font-family: var(--font-mono);
    cursor: pointer;
    transition: all 0.2s ease;
  }
  
  .lang-btn:hover {
      color: var(--color-text-primary);
      background-color: rgba(0,0,0,0.03);
  }

  .lang-btn.active {
    color: var(--color-text-primary);
    background-color: var(--color-surface);
  }

  /* --- Mega Menu --- */
  .mega-menu {
    position: absolute;
    top: 80px;
    left: 0;
    width: 100%; /* Spans full width of .header-inner */
    margin-top: 8px; /* Move lower */
    background: #FFFFFF;
    border: 1px solid rgba(0,0,0,0.06);
    box-shadow: 0 20px 40px rgba(0,0,0,0.08); /* Keep shadow for separation */
    border-radius: 16px; /* Rounded corners (detached look) */
    padding: 2.5rem 3rem; /* More generous padding */
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
    cursor: default;
    z-index: 999;
  }

  /* Click Logic: Show menu when parent GROUP has .active class */
  .nav-group.active .mega-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .mega-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem; /* Wide gap */
    max-width: 1200px; /* Optional constraint inside the full width container */
  }

  .mega-col {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
  }

  .mega-item {
    display: flex;
    align-items: flex-start; /* Align icon with top of text */
    gap: 1rem;
    padding: 1rem;
    margin: -1rem;
    margin: -1rem;
    border-radius: 8px;
    text-decoration: none;
    cursor: pointer;
  }

  .mega-item:hover {
    background-color: transparent;
  }

  /* Icons */
  .mega-icon {
    width: 40px;
    height: 40px;
    flex-shrink: 0;
    background-color: transparent;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .mega-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    opacity: 0.9;
  }

  .mega-content {
      display: flex;
      flex-direction: column;
      gap: 0.25rem;
  }

  .mega-title {
    font-size: 1rem;
    font-weight: 600; /* Semibold */
    font-family: 'IBM Plex Mono', monospace; /* Enforce IBM Plex Mono */
    color: var(--color-text-primary);
  }

  .mega-desc {
    font-size: 0.8rem;
    color: var(--color-text-secondary); /* Text secondary color */
    line-height: 1.5;
    font-family: 'IBM Plex Mono', monospace; /* Enforce IBM Plex Mono */
    opacity: 0.8;
  }
}