.nav-horizontal{
  background-color: $grey-3;
  overflow: hidden;
  
  .main-nav-wrapper{
    width: 100%;
    
    ul {
      padding-left: 40px;
      float: left;
      margin: 0;
    }
    
    li{
      float: left;

      a {
        display: inline-block;
        padding: 15px;
        text-decoration: none;
        color: $black;
      }
      &.selected a, &.selected a:hover {
        background-color: $turquoise;
        font-weight: bold;
        color: $white;
      }
    }  
  }

  .external-links-wrapper{
    float:right;

    ul {
      list-style: none;
      padding: 15px 40px;
    }

    li {
      display: inline;
    
      a {
        color: $govuk-blue;
        font-size: 16px
      }
    }
  }
}
.nav-horizontal{
  background-color: $grey-3;
  overflow: hidden;
  
  .main-nav-wrapper{
    width: 100%;
    
    ul {
      padding-left: 40px;
      float: left;
      margin: 0;
    }
    
    li{
      float: left;

      a {
        display: inline-block;
        padding: 15px;
        text-decoration: none;
        color: $black;
      }
      &.selected a, &.selected a:hover {
        background-color: $turquoise;
        font-weight: bold;
        color: $white;
      }
    }  
  }

  .external-links-wrapper{
    float:right;

    ul {
      list-style: none;
      padding: 15px 40px 15px 0;
    }

    li {
      display: inline;
    
      a {
        color: $govuk-blue;
        font-size: 16px
      }
    }
  }
}
Save some space for the external links
Save some space for the external links
