// Adds combination of margin and padding to headings to make them appear
// correctly when they're linked to as anchors, and scale them on mobile
@mixin heading-offset($tabletTopMargin) {
  // Scale margins with font size on mobile (16/19ths)
  $mobileTopMargin: ceil($tabletTopMargin * (16 / 19));

  // Offset headings down on mobile so that linking to anchors they appear after
  // the sticky 'table of contents' element
  $stickyTocOffset: 20px + $gutter-half + 10px + 1px;

  // Pad the heading so that when linking to an anchor there is at most a
  // $gutter-half (mobile) or $gutter (tablet and above) sized gap between the
  // top of the viewport and the heading.
  padding-top: min($mobileTopMargin, $gutter-half) + $stickyTocOffset;
  margin-top: max(0, $mobileTopMargin - $gutter-half) - $stickyTocOffset;

  @include media(tablet) {
    padding-top: min($tabletTopMargin, $gutter);
    margin-top: max(0, $tabletTopMargin - $gutter);
  }
}

.technical-documentation {
  // Required for IE11 to render <main> correctly
  display: block;
  margin: 0 $gutter-half 10px;
  max-width: 40em;

  line-height: 1.4;

  color: $text-colour;

  @include media(tablet) {
    // We add 2 pixels to the gutter here to ensure there's sufficient spacing between
    // an anchor link (see _anchored-heading.scss) on a heading and the left-hand pane.
    margin: 0 ($gutter + 2px) $gutter;
  }

  .has-search-results-open & {
    visibility: hidden;
  }

  // Headings
  h1 {
    @include bold-48;
    @include heading-offset($gutter * 2);
    border-top: 5px solid $text-colour;

    &:first-of-type {
      @include heading-offset($gutter);
      border-top: none;
    }
  }

  h2 {
    @include bold-36;
    @include heading-offset($gutter * 1.5);
  }

  h3, h4, h5, h6 {
    @include heading-offset($gutter);
  }

  h3 {
    @include bold-24;
  }

  h4 {
    @include bold-19;
  }

  h5 {
    @include bold-19;
    color: $secondary-text-colour;
  }

  h6 {
    @include core-19;
    color: $secondary-text-colour;
  }

  // Expand margin when h1 followed directly by paragraph
  h1 + p {
    @include media(tablet) {
      margin-top: $gutter * 1.5;
    }
  }

  // Tighten up margins where headings follow each other
  h1 + h2 {
    @include heading-offset($gutter);
  }

  h2 + h3, h3 + h4, h4 + h5, h5 + h6 {
    @include heading-offset(20px);
  }

  p {
    margin-top: ceil($gutter-half * (16 / 19));
    margin-bottom: 0;

    @include media(tablet) {
      margin-top: $gutter-half;
    }
  }

  img {
    max-width: 100%;
    width: auto;
    height: auto;
  }

  ol, ul {
    margin: $gutter-half 0 0;
    padding-left: 20px;
  }

  ol ol, ul ul, ol ul, ul ol {
    margin-top: 0;
  }

  li {
    margin-top: 5px;
  }

  ol + p, ul + p, .table-container + p {
    margin-top: ceil($gutter * (16 / 19));

    @include media(tablet) {
      margin-top: $gutter;
    }
  }

  blockquote {
    background: $grey-4;
    padding: $gutter-half;
    margin: $gutter-half;
    border-left: 5px solid $grey-3;
  }

  pre {
    background: $code-00;
    padding: 15px;
    overflow: auto;
    position: relative;
    border: 1px solid $code-02;
    // Restrict the width of pre tags, as they have a tendency grow larger than
    // the viewport when placed within table cells.
    // @todo: Use table-layout: fixed, and remove the max-width definition from
    // .technical-documentation so tables can fill the viewport.
    max-width: 40em;
  }

  pre code {
    background: none;
    color: inherit;
    padding: 0;
  }

  code {
    background: $code-01;
    padding: 3px 5px;
    border-radius: 1px;

    font-family: monaco, Consolas, "Lucida Console", monospace;
    font-size: 15px;
    color: $code-0E;

    @include media(tablet) {
      font-size: 16px;
    }

    // Handle long strings (URLs, long variable names, etc) by allowing them
    // to break anywhere if required.
    overflow-wrap: break-word;
    word-wrap: break-word;

    -ms-word-break: break-all;
    /* This is the dangerous one in WebKit, as it breaks things wherever */
    word-break: break-all;
    /* Instead use this non-standard one: */
    word-break: break-word;
  }

  // Support monospace headings for e.g. listing API endpoints
  h1, h2, h3, h4, h5, h6 {
    code {
      font-size: inherit;
      color: $text-colour;
      background: none;
      padding: 0;
    }
  }

  .table-container {
    display: block;
    max-width: 100%;
    overflow-x: auto;

    margin-top: $gutter-half;
  }

  table {
    width: 100%;

    border-collapse: collapse;
    border-spacing: 0;
  }

  th, td {
    padding: $gutter-one-third $gutter-two-thirds $gutter-one-third 0;

    background-color: transparent;
    border-bottom: 1px solid $border-colour;
    border-width: 0 0 1px 0;

    @include core-16;
    vertical-align: top;
    text-align: left;
  }

  th {
    font-weight: bold;
  }

  td {
    p, ul, ol {
      margin: 0;
    }
    p+p, p+ul, p+ol,
    ul+p, ul+ol,
    ol+p {
      margin-top: $gutter-one-third;
    }
  }

  hr {
    height: 1px;
    border: none;
    margin-top: $gutter - 1px;
    margin-bottom: $gutter;
    background-color: $border-colour;
    color: $border-colour;
  }
}