/* css/layout.css */

body {
  font-family: var(--font-body);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Page fade-in transition */
.page-fade-in {
  animation: fadeIn var(--transition-slow) forwards;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Layout Container */
.container {
  width: 100%;
  max-width: var(--max-width-content);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-md);
  padding-right: var(--space-md);
}

/* Skip to Content Link (Accessibility) */
.skip-link {
  position: absolute;
  top: -100px;
  left: 0;
  background: var(--color-accent);
  color: var(--bg-primary);
  padding: var(--space-sm) var(--space-md);
  z-index: 9999;
  text-decoration: none;
  font-weight: 600;
  border-bottom-right-radius: var(--radius-md);
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 0;
}

/* Header & Navigation */
.site-header {
  position: sticky;
  top: 0;
  height: var(--header-height);
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  display: flex;
  align-items: center;
  box-shadow: 0 4px 30px var(--shadow-color);
  backdrop-filter: blur(10px);
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

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

.logo-link {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  text-decoration: none;
  color: var(--text-primary);
  font-family: var(--font-title);
  font-size: 1.5rem;
  font-weight: 700;
}

.logo-icon {
  width: 32px;
  height: 32px;
  fill: var(--color-accent);
}

.nav-menu {
  display: flex;
  align-items: center;
  list-style: none;
  gap: var(--space-lg);
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
  position: relative;
  padding: var(--space-2xs) 0;
  transition: color var(--transition-fast);
}

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

/* Custom underline animation for nav links */
.nav-link::after {
  content: '';
  position: absolute;
  width: 100%;
  transform: scaleX(0);
  height: 2px;
  bottom: 0;
  left: 0;
  background-color: var(--color-accent);
  transform-origin: bottom right;
  transition: transform var(--transition-fast) ease-out;
}

.nav-link:hover::after,
.nav-link.active::after {
  transform: scaleX(1);
  transform-origin: bottom left;
}

/* Header Utilities */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* Theme Toggle Button */
.theme-toggle-btn {
  background: none;
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: border-color var(--transition-fast), background-color var(--transition-fast);
}

.theme-toggle-btn:hover {
  background-color: var(--bg-secondary);
  border-color: var(--color-accent);
}

.theme-toggle-btn svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
}

.theme-toggle-btn .sun-icon {
  display: none;
}

[data-theme="dark"] .theme-toggle-btn .sun-icon {
  display: block;
}

[data-theme="dark"] .theme-toggle-btn .moon-icon {
  display: none;
}

/* Mobile Menu Button */
.mobile-nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  width: 44px;
  height: 44px;
  cursor: pointer;
  z-index: 1100;
  position: relative;
  aria-haspopup: "true";
}

.mobile-nav-toggle svg {
  width: 24px;
  height: 24px;
  fill: currentColor;
}

/* Responsive Styles for Navigation */
@media (max-width: 900px) {
  .mobile-nav-toggle {
    display: block;
  }

  .nav-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background-color: var(--bg-secondary);
    box-shadow: -10px 0 30px var(--shadow-color);
    flex-direction: column;
    padding: calc(var(--header-height) + var(--space-xl)) var(--space-lg) var(--space-lg);
    align-items: flex-start;
    gap: var(--space-md);
    transition: right var(--transition-normal);
    z-index: 1050;
  }

  .nav-menu.open {
    right: 0;
  }

  .nav-link {
    font-size: 1.1rem;
    width: 100%;
    display: block;
    padding: var(--space-xs) 0;
  }
}

/* Main Content Area */
.main-content {
  flex: 1;
}

/* Footer Section */
.site-footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: var(--space-2xl) 0 var(--space-md);
  margin-top: auto;
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.footer-logo {
  font-family: var(--font-title);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
}

.footer-text {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.footer-heading {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.footer-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.9rem;
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--color-accent);
}

.footer-socials {
  display: flex;
  gap: var(--space-sm);
}

.social-icon-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.social-icon-link:hover {
  background-color: var(--color-accent);
  color: var(--bg-primary);
}

.social-icon-link svg {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: var(--space-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-md);
  font-size: 0.85rem;
  color: var(--text-muted);
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
  }
}

@media (max-width: 480px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }
  
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}