homepage/styles/_components.scss

@use 'colors';
@use 'layout';
@use 'typography';

// --------------------
// Site-wide components
// --------------------

@mixin header-item {
  padding: 0 layout.$normal-gap;
  line-height: 3rem;
}

// The site logo text. More specific styles for this element are also present
// underneath .site-header.
.site-logo {
  margin: 0 layout.$normal-gap;
  text-transform: lowercase;
}

// The navigation is present twice on the site: once in the header and once in
// the footer. The former also has some specific styles (see .site-header
// below).
.site-navigation {
  &.horizontal {
    > ul {
      display: flex;
      margin-bottom: 0;
    }

    a {
      display: inline-block;
      @include header-item;
    }
  }

  > ul {
    margin: 0;
    padding: 0;
    list-style: none;
  }

  a {
    display: block;
    padding: layout.$small-gap;
    font-size: typography.$large-size;
    font-weight: typography.$emphasized-weight;
    text-align: center;
    text-decoration: none;
    text-transform: lowercase;
  }
}

.site-mobile-navigation {
  cursor: pointer;

  > summary {
    display: block;
    @include header-item;
  }

  &[open] {
    flex-basis: 100%;

    > summary {
      // The positioning requires that the header component has relative
      // positioning.
      position: absolute;
      top: 0;
      right: 0;
      color: colors.$blue-800;
    }
  }

  // This is the next site navigation block (the one that's visible on desktop),
  // while...
  + .site-navigation {
    display: none;
  }

  // ... this here is the one inside the mobile-only <details> block.
  > .site-navigation {
    &::before {
    content: '';
    display: block;
    margin: 0 auto;
    width: calc(100% - #{2 * layout.$normal-gap});
    height: 1px;
    background-color: colors.$gray-300;
    }
  }

  @media screen and (min-width: layout.$breakpoint) {
    display: none;

    + .site-navigation {
      display: block;
    }
  }
}

.site-header {
  display: flex;
  // This container needs to wrap because when the navigation is open on small
  // screens, we want it to overflow into its own line.
  flex-wrap: wrap;
  align-items: center;
  // Relative positioning is required here so that we can fake the menu button's
  // location on mobile.
  position: relative;
  z-index: 10;
  background-color: colors.$main-background;
  @include colors.block-shadow;

  > .site-logo {
    flex-grow: 1;
    margin: 0;
    font-size: typography.$large-size;
    text-decoration: none;
    @include header-item;
  }
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: layout.$normal-gap;
}

// ------------------------------
// Components on individual pages
// ------------------------------

// This is the wrapper element around individual .page-content blocks. The home
// page contains a few of these sections, while normal pages only contain one.
// Spanning the entire width, sections may have different themes.
.page-section {
  padding: layout.$large-gap;

  &.inverse {
    color: colors.$gray-50;
    background-color: colors.$blue-800;

    h2:after {
      background-color: colors.$gray-50;
    }
  }

  &.footer {
    background-color: colors.$teal-500;
  }
}

.page-content {
  margin: 0 auto;
  max-width: 80rem;
}

// Banners can be put at the top of a page to draw attention. A banner has
// two children:
// - A .background element which contains an image to render behind the text
// - A .content which holds the actual text.
.page-banner {
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  position: relative;
  min-height: 60vh;

  > .background {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    overflow: hidden;

    img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
  }

  > .content {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    position: relative;
    padding: layout.$normal-gap max(#{layout.$large-gap}, 15vw);

    > div {
      display: inline-block;
      padding: layout.$small-gap layout.$normal-gap;
      font-size: typography.$large-size;
      background-color: colors.$yellow-600;

      > p:first-child {
        margin-top: 0;
      }

      > p:last-child {
        margin-bottom: 0;
      }
    }

    > .title {
      padding: 0 layout.$normal-gap;
      line-height: 5rem;
      font-size: typography.$huge-size;
      font-weight: typography.$emphasized-weight;
      background-color: colors.$teal-500;
    }
  }
}

.boxes-module {
  padding: layout.$large-gap;
  background-color: colors.$teal-300;

  .content,
  .box {
    &:not(:last-child) {
      margin-bottom: layout.$large-gap;
    }
  }

  .content {
    > *:first-child {
      margin-top: 0;
    }

    > *:last-child {
      margin-bottom: 0;
    }
  }

  .box {
    margin: layout.$large-gap 0;
    padding: layout.$large-gap;
    background: colors.$gray-50;
    @include colors.card-shadow;

    h3 {
      margin: 0;
      text-transform: uppercase;
    }
  }

  @media screen and (min-width: layout.$breakpoint) {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: layout.$large-gap;

    .content,
    .box {
      grid-column: span 3;
      margin: 0;

      &:not(:last-child) {
        margin-bottom: 0;
      }
    }

    .box:not(.first) {
      grid-column: span 2;
    }
  }
}

// This is an HTML/CSS-only tabs component. It expects the following markup:
//
//   <div class="tabs-widget">
//     <div id="second" class="tab">Other, totally novel content.</div>
//     <a href="#second" rel="tab">Second</a>
//     <div id="first" class="tab">Some content, including a heading.</div>
//     <a href="#first" rel="tab">First</a>
//   </div>
//
// The key thing here is that the container is a flexbox with that flows in
// reverse row direction. That means that the first element in the container
// <div> will be shown last, which means we can use the ~ and + selectors to
// target all and the immediately following tabs and / or their corresponding
// links.
// The last tab in the DOM (which is shown first because of the reversed
// flexbox) is shown by default, while the other ones are hidden. If one of the
// tabs is targeted by the URL's hash, it is shown instead and the default tab
// is hidden.
.tabs-widget {
  display: flex;
  flex-direction: row-reverse;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: #{-1 * layout.$large-gap};

  > a {
    display: block;
    margin: 0 layout.$normal-gap;
    text-decoration: none;
    color: inherit;
  }

  > .tab {
    flex: 100% 1;
    order: -1;
    display: none;
    margin: layout.$large-gap 0;
    padding: layout.$large-gap;
    background: colors.$gray-50;
    @include colors.card-shadow;

    &:last-of-type,
    &:target {
      display: block;

      + a {
        font-weight: typography.$emphasized-weight;
        color: colors.$blue-800;
      }
    }

    &:target {
      ~ .tab {
        display: none;

        + a {
          font-weight: inherit;
          color: inherit;
        }
      }
    }
  }
}