/* Header & Navigation Styles */

header {
  position: sticky;
  top: 0;
  background-color: var(--bg);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  box-shadow: var(--shadow-sm);
  transition: background-color var(--transition-slow);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem var(--spacing-md);
  max-width: 1200px;
  margin: 0 auto;
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--text);
  text-decoration: none;
  white-space: nowrap;
}

.logo:hover {
  color: var(--primary);
}

.logo svg {
  width: 40px;
  height: 40px;
}

/* Navigation */
nav {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
  flex: 1;
  justify-content: center;
}

nav a {
  font-weight: var(--font-weight-medium);
  position: relative;
  color: var(--text);
  padding: 0.25rem 0;
}

nav a[aria-current="page"] {
  color: var(--primary);
}

nav a[aria-current="page"]::after {
  width: 100%;
}

nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--primary);
  transition: width var(--transition-base);
}

nav a:hover::after {
  width: 100%;
}

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

/* Theme Toggle Button */
.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  transition: background-color var(--transition-base);
}

.theme-toggle:hover {
  background-color: var(--accent);
}

.theme-toggle svg {
  width: 24px;
  height: 24px;
  stroke: var(--text);
  fill: none;
  stroke-width: 2;
}

/* CTA Button */
.header-cta {
  white-space: nowrap;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
  flex-direction: column;
  gap: 4px;
}

.mobile-menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--text);
  transition: all var(--transition-base);
}

.mobile-menu-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(6px, 6px);
}

.mobile-menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(6px, -6px);
}

/* Mobile Navigation */
@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: flex;
  }

  nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--bg);
    flex-direction: column;
    gap: 0;
    padding: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-base);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
  }

  nav.active {
    max-height: min(75vh, 640px);
    overflow-y: auto;
  }

  nav a {
    display: block;
    padding: var(--spacing-md);
    border-bottom: 1px solid var(--border);
  }

  nav a::after {
    display: none;
  }

  .header-container {
    padding: 1rem var(--spacing-md);
  }

  .logo {
    font-size: var(--font-size-base);
  }

  .header-actions {
    gap: var(--spacing-sm);
  }

  .header-cta {
    display: none;
  }
}

@media (max-width: 480px) {
  .logo {
    font-size: var(--font-size-sm);
  }

  .logo svg {
    width: 32px;
    height: 32px;
  }

  .header-actions {
    gap: var(--spacing-xs);
  }
}