/* Container */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-6);
}

@media (max-width: 768px) {
  .container {
    padding: 0 var(--space-4);
  }
}

/* Sections */
.section {
  padding: var(--space-16) 0;
}

.section-sm {
  padding: var(--space-8) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-12);
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.section-subtitle {
  color: var(--color-accent);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-size: 0.875rem;
  margin-bottom: var(--space-2);
  display: block;
}

/* Grid Layouts */
.grid {
  display: grid;
  gap: var(--space-6);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 992px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

/* Page Layout */
.page-container {
  padding-top: 80px; /* Header height offset */
}

/* Header */
.app-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 80px;
  z-index: var(--z-header);
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--glass-border);
  transition: all var(--transition-normal);
}

.app-header.solid {
  background: var(--color-surface);
  border-bottom-color: var(--color-border);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-primary);
  text-decoration: none;
}

[data-theme="dark"] .brand {
  color: var(--color-white);
}

.brand-icon {
  width: 32px;
  height: 32px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-6);
}

.nav-link {
  color: var(--color-text);
  font-weight: 500;
  font-size: 0.9375rem;
  transition: color var(--transition-fast);
}

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

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.theme-toggle, .mobile-menu-btn {
  background: none;
  border: none;
  color: var(--color-text);
  font-size: 1.25rem;
  cursor: pointer;
  padding: var(--space-2);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
}

.theme-toggle:hover, .mobile-menu-btn:hover {
  background-color: var(--color-border-light);
}

.mobile-menu-btn {
  display: none;
}

/* Light/Dark Toggle Icons */
[data-theme="dark"] .fa-moon { display: none; }
[data-theme="light"] .fa-sun { display: none; }
:root:not([data-theme]) .fa-sun { display: none; } /* Default light */

@media (max-width: 992px) {
  .nav-links { display: none; }
  .header-actions .btn { display: none; }
  .mobile-menu-btn { display: flex; }
}

/* Mobile Drawer */
.mobile-drawer {
  position: fixed;
  top: 80px;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--color-bg);
  z-index: calc(var(--z-header) - 1);
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  transform: translateX(100%);
  transition: transform var(--transition-normal);
  overflow-y: auto;
}

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

.mobile-drawer .nav-link {
  font-size: 1.25rem;
  display: block;
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-border-light);
}

/* Footer */
.app-footer {
  background-color: var(--color-primary-dark);
  color: var(--color-white);
  padding: var(--space-12) 0 var(--space-6);
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-8);
  margin-bottom: var(--space-12);
}

@media (max-width: 992px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 576px) {
  .footer-grid { grid-template-columns: 1fr; }
}

.footer-brand {
  margin-bottom: var(--space-4);
  color: var(--color-white);
}

.footer-desc {
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: var(--space-6);
  max-width: 300px;
}

.footer-social {
  display: flex;
  gap: var(--space-3);
}

.social-icon {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-white);
  transition: all var(--transition-fast);
}

.social-icon:hover {
  background-color: var(--color-accent);
  transform: translateY(-2px);
}

.footer-h {
  font-size: 1.125rem;
  margin-bottom: var(--space-4);
  color: var(--color-white);
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: var(--space-3);
}

.footer-links a {
  color: rgba(255, 255, 255, 0.7);
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--color-accent);
  padding-left: var(--space-1);
}

.footer-bottom {
  padding-top: var(--space-6);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
  color: rgba(255, 255, 255, 0.5);
  font-size: 0.875rem;
}

.footer-certs {
  display: flex;
  gap: var(--space-4);
  align-items: center;
}