/* ==========================================================================
   GET ENGINEERING SEAT — Responsive Foundation (v1.1)
   Authoritative Breakpoints:
   - Mobile:         < 640px
   - Tablet:         640px – 1023px
   - Laptop/Desktop: 1024px – 1279px
   - Large Desktop:  >= 1280px
   ========================================================================== */

/* 1. Mobile & Tablet (< 1024px): Bottom Nav Clearance & Compact Header */
@media (max-width: 1023.98px) {
  /* Defensive horizontal overflow prevention */
  html, body {
    overflow-x: hidden;
  }

  /* Reserve bottom clearance so fixed bottom nav never obscures content */
  body {
    padding-bottom: calc(4.25rem + env(safe-area-inset-bottom, 0px));
  }

  /* Compact Header: Desktop-only navigation and desktop auth controls move into mobile drawer */
  .site-nav {
    display: none !important;
  }

  .site-action-search,
  .site-action-saved,
  .site-header-auth,
  .site-header-divider {
    display: none !important;
  }

  .mobile-nav-toggle,
  .nav-toggle-btn {
    display: flex !important;
  }

  .site-header-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
  }
}

/* 2. Tablet Layout (640px – 1023.98px) */
@media (min-width: 640px) and (max-width: 1023.98px) {
  .grid-cols-3,
  .grid-cols-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  /* Footer 2-column grid on tablet */
  .footer-grid,
  .site-footer-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-6);
  }
}

/* 3. Small Screen Adjustments (< 640px) */
@media (max-width: 639.98px) {
  /* Responsive Typography */
  h1, .h1 { font-size: var(--font-size-3xl, 2.25rem); }
  h2, .h2 { font-size: var(--font-size-2xl, 1.875rem); }
  h3, .h3 { font-size: var(--font-size-xl, 1.5rem); }

  /* Compact Brand in Header */
  .site-brand-tagline {
    display: none !important;
  }

  .site-action-label {
    display: none !important;
  }

  /* Grid Collapse */
  .grid-cols-2,
  .grid-cols-3,
  .grid-cols-4 {
    grid-template-columns: repeat(1, minmax(0, 1fr));
  }

  /* Footer 1-column single stack on mobile */
  .footer-grid,
  .site-footer-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-8);
  }

  .footer-bottom,
  .site-footer-bottom {
    flex-direction: column;
    gap: var(--spacing-3);
    text-align: center;
  }

  /* Full-width button utility on mobile */
  .btn-block-mobile {
    width: 100%;
  }
}

/* 4. Desktop & Above (>= 1024px) */
@media (min-width: 1024px) {
  .mobile-nav-toggle,
  .nav-toggle-btn {
    display: none !important;
  }

  .site-nav {
    display: flex;
  }

  .mobile-bottom-nav {
    display: none !important;
  }

  body {
    padding-bottom: 0 !important;
  }
}

/* 4b. Standard Desktop Viewport Adjustments (1024px – 1366px) */
@media (min-width: 1024px) and (max-width: 1366px) {
  /* Breakpoint range: 1024px - 1279.98px / 1366px */
  .site-brand-tagline {
    display: none;
  }

  .site-action-label {
    display: none;
  }

  .site-nav-list {
    gap: var(--spacing-3);
  }

  .site-nav-link {
    font-size: 0.8125rem;
  }

  .site-header-inner {
    gap: var(--spacing-2);
  }
}

/* 5. Large Desktop Enhancements (>= 1280px) */
@media (min-width: 1280px) {
  .container {
    max-width: var(--container-xl, 1280px);
  }
}

/* ==========================================================================
   Mobile Bottom Navigation Bar (Screens < 1024px)
   Strictly horizontal 5-column grid layout
   ========================================================================== */
.mobile-bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3.75rem; /* 60px */
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border);
  box-shadow: 0 -2px 10px rgba(15, 23, 42, 0.08);
  z-index: var(--z-fixed, 300);
  display: flex;
  align-items: center;
}

.mobile-bottom-nav-list {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
  list-style: none;
}

.mobile-bottom-nav-item {
  display: flex;
  align-items: stretch;
  justify-content: center;
  height: 100%;
  min-width: 0;
}

.mobile-bottom-nav-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  padding: 4px 2px;
  gap: 2px;
  font-size: 0.6875rem; /* 11px */
  color: var(--color-text-muted);
  text-decoration: none !important;
  transition: color var(--transition-fast);
  min-width: 0;
  text-align: center;
}

.mobile-bottom-nav-link:hover,
.mobile-bottom-nav-link.active {
  color: var(--color-secondary);
}

[data-theme="dark"] .mobile-bottom-nav-link {
  color: var(--color-text-muted);
}

[data-theme="dark"] .mobile-bottom-nav-link:hover,
[data-theme="dark"] .mobile-bottom-nav-link.active {
  color: var(--color-teal-bright, #2dd4bf);
  font-weight: var(--font-weight-bold);
}

.mobile-bottom-nav-icon {
  font-size: 1.125rem;
  line-height: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.mobile-bottom-nav-label {
  font-size: 0.6875rem;
  font-weight: var(--font-weight-medium);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 100%;
}

.mobile-nav-prominent .mobile-bottom-nav-icon {
  color: var(--color-secondary);
  font-weight: var(--font-weight-bold);
}

[data-theme="dark"] .mobile-nav-prominent .mobile-bottom-nav-icon {
  color: var(--color-teal-bright, #2dd4bf);
}