@layer header {
  .site-header {
    position: relative;
    z-index: 1000;
    background-color: var(--chalk);
    border-bottom: var(--border-subtle);
  }

  .site-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-16);
    max-width: var(--container-max);
    margin-inline: auto;
    padding-inline: var(--page-margin-mobile);
    min-height: 56px;
  }

  .site-header__brand {
    display: inline-flex;
    align-items: center;
    gap: var(--space-8);
    flex-shrink: 0;
    text-decoration: none;
    color: var(--charcoal);
  }

  .site-header__logo {
    width: 36px;
    height: 36px;
    object-fit: contain;
    display: block;
  }

  .site-header__brand-text {
    font-family: var(--font-heading);
    font-size: 1rem;
    font-weight: 600;
    letter-spacing: 0;
    white-space: nowrap;
  }

  .site-header__toggle {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    padding: 0;
    background: none;
    border: none;
    cursor: pointer;
    border-radius: var(--radius-control);
    transition: background-color var(--transition-fast);
  }

  .site-header__toggle:hover {
    background-color: rgba(43, 43, 43, 0.08);
  }

  .site-header__toggle:focus-visible {
    outline: var(--border-focus);
    outline-offset: 2px;
  }

  .site-header__toggle-line {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--charcoal);
    transition: transform var(--transition-fast), opacity var(--transition-fast);
    transform-origin: center;
  }

  .site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(2) {
    opacity: 0;
  }

  .site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .site-header__nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--cobalt);
    padding: var(--space-16) var(--page-margin-mobile) var(--space-24);
    max-height: calc(100vh - 56px);
    overflow-y: auto;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.15);
  }

  .site-header__nav.is-open {
    display: block;
  }

  .site-header__nav-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: var(--space-8);
  }

  .site-header__nav-item {
    margin: 0;
    padding: 0;
  }

  .site-header__nav-link {
    display: block;
    padding: var(--space-12) var(--space-16);
    font-family: var(--font-body);
    font-size: var(--text-body);
    font-weight: 500;
    color: var(--chalk);
    text-decoration: none;
    border-radius: var(--radius-control);
    transition: background-color var(--transition-fast), color var(--transition-fast);
  }

  .site-header__nav-link:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--saffron);
  }

  .site-header__nav-link:focus-visible {
    outline: 2px solid var(--saffron);
    outline-offset: 2px;
  }

  @media (min-width: 768px) {
    .site-header__inner {
      min-height: 64px;
      padding-inline: var(--page-margin-tablet);
    }

    .site-header__logo {
      width: 44px;
      height: 44px;
    }

    .site-header__brand-text {
      font-size: 1.125rem;
    }

    .site-header__toggle {
      display: none;
    }

    .site-header__nav {
      display: block;
      position: static;
      background-color: transparent;
      padding: 0;
      max-height: none;
      overflow: visible;
      box-shadow: none;
    }

    .site-header__nav-list {
      flex-direction: row;
      align-items: center;
      gap: var(--space-24);
    }

    .site-header__nav-link {
      padding: var(--space-8) 0;
      color: var(--charcoal);
      font-size: var(--text-small);
      position: relative;
    }

    .site-header__nav-link::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: 0;
      width: 100%;
      height: 2px;
      background-color: var(--saffron);
      transform: scaleX(0);
      transform-origin: left;
      transition: transform var(--transition-fast);
    }

    .site-header__nav-link:hover::after,
    .site-header__nav-link:focus-visible::after {
      transform: scaleX(1);
    }

    .site-header__nav-link:hover {
      background-color: transparent;
      color: var(--cobalt);
    }

    .site-header__nav-link:focus-visible {
      outline: var(--border-focus);
      outline-offset: 2px;
    }
  }

  @media (min-width: 1024px) {
    .site-header__inner {
      padding-inline: var(--page-margin-desktop);
    }
  }
}