site/docs/assets/scss/_main-header.scss

.skip-link {
  position: fixed;
  top: -30em;
  left: 0;
  right: 0;
  z-index: 20;
  background: $white;;
  color: $dark-purple;
  padding: .5em 1em;
  font-size: 1em;
  text-align: center;
  transition: top .1s linear;
  text-decoration: none;

  &:focus, 
  &:focus-visible {
    top: 0;
    color: $dark-purple;
  }
}

.main-header {
  margin: 0 auto;
  // max-width: $max-width-m;
  max-width: $max-width-l;
  padding: 1.75em $m-s;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;

  &:after {
    content: "";
    display: block;
    flex-grow: 9999;
    height: 1em;
    order: 2;
    flex-basis: calc((40em - 100%) * 999);
  }
}

@media print {
  .skip-link, .main-header {
    display: none;
  }
}

.logo {
  font-size: 1em;
  width: 12.5em;
  max-height: 2.375em;
  min-width: 12.5em;
  order: 1;
  flex-grow: 1;
  flex-basis: calc((40em - 100%) * 999);

  svg {
    width: 12.5em;
    height: 2.375em;
    display: block;
    margin: 0 auto;
  }

  a {
    display: block;
    &:focus {
      outline: 1px dashed $white;
      outline-offset: 0.5em;
    }
  }
}

.main-nav {
  order: 3;
  flex-grow: 1;
  flex-basis: calc((40em - 100%) * 999);

  &__list {
    display: flex;
    justify-content: center;
  }

  &__item {
    & + & {
      margin-left: 2em;
    }

    a {
      color: $white;
      color: var(--text-white);
      text-decoration: none;
      font-weight: 700;
      font-size: 1.125em;
      display: block;
      position: relative;
      padding: 0.25em 0;

      &:after {
        content: "";
        position: absolute;
        left: 0;
        bottom: 0;
        right: 0;
        height: 3px;
        background: $white;
        background: var(--text-white);
        transform: scaleX(0);
        transition: transform 0.4s ease-in-out;
        will-change: transform;
      }

      &:hover:after {
        transform: scaleX(1);
        transition-timing-function: cubic-bezier(.21,1.45,.51,1)
      }

      &:focus {
        outline: 1px dashed $white;
        outline-offset: 0.3em;
      }
    }
  }
}