.vertical-tabs-container { // small screens: accordion
  $tab-border-color: $base-border-color;
  $tab-border: 1px solid $tab-border-color;
  $tab-border-radius: $base-border-radius;
  $tab-content-background: lighten($tab-border-color, 10);
  $tab-active-color: $tab-content-background;
  $tab-inactive-color: $base-background-color;
  $vertical-tabs-height: em(300);
  $vertical-tab-mode: $medium-screen;

  @include clearfix;
  border-radius: $tab-border-radius;
  border: $tab-border;
  margin-bottom: $base-spacing;
  overflow: hidden;

  .vertical-tabs {
    display: none;

    @include media($vertical-tab-mode) {
      background-color: $tab-inactive-color;
      display: inline;
      float: left;
      height: $vertical-tabs-height;
      width: 20%;
    }
  }

  .vertical-tab {
    @include media($vertical-tab-mode) {
      border-bottom: $tab-border;
      display: block;
      font-weight: bold;
      margin-right: -1px;
      padding: $base-spacing/2 $gutter/2;

      &.is-active {
        background-color: $tab-content-background;
        margin-right: -1px;
      }
    }
  }

  a.vertical-tab-accordion-heading,
  a.vertical-tab {
    color: $dark-gray;
  }

  .vertical-tab:focus {
    outline: none; 
  }

  .vertical-tab-content-container {
    display: block;
    margin: 0 auto;

    & a:focus { 
      outline: none; 
    }

    @include media($vertical-tab-mode) {
      @include inline-block;
      @include size(80% $vertical-tabs-height);
      background-color: $tab-content-background;
    }
  }

  .vertical-tab-content {
    background-color: $tab-content-background;
    padding: $base-spacing $gutter;

    @include media($vertical-tab-mode) {
      border: none;
      display: none;
    }
  }

  .vertical-tab-accordion-heading {
    background-color: $tab-inactive-color;
    border-top: $tab-border;
    cursor: pointer;
    display: block;
    font-weight: bold;
    padding: $base-spacing/2 $gutter/2;

    &:hover {
      color: $base-accent-color;
    }

    &:first-child {
      border-top: none;
    }

    &.is-active {
      background: $tab-active-color;
      border-bottom: none;
    }

    @include media($vertical-tab-mode) {
      display: none;
    }
  }
}

// Based on code by Jett Miller jettmiller.net