Integrate Drupal 8 Toolbar w/ Bootstrap Fixed Top Nav

mytheme.info.yml

libraries-extend:
  # Improve interoperability between MyTheme and the Drupal admin toolbar.
  toolbar/toolbar:
    - mytheme/toolbar

mytheme.libraries.yml

toolbar:
  css:
    theme:
      css/toolbar.css: {}

toolbar.css

@media only screen and (max-width: 976px) {
  .toolbar-fixed .navbar.fixed-top {
    top: 39px !important;
  }

  .toolbar-fixed.toolbar-horizontal.toolbar-tray-open:not(.toolbar-loading) .navbar.fixed-top {
    top: 79px !important;
  }
}

@media only screen and (min-width: 977px) and (max-width: 1024px) {
  .toolbar-fixed .navbar.fixed-top {
    top: 39px !important;
  }

  .toolbar-fixed.toolbar-horizontal.toolbar-tray-open .navbar.fixed-top {
    top: 79px !important;
  }
}

/* Ensure navbar scrolls when toolbar is also configured to scroll on smaller screens or when loading. */
@media only screen and (max-width: 1024px) {
  .toolbar-loading .navbar.fixed-top,
  .toolbar-vertical:not(.toolbar-fixed) .navbar.fixed-top {
    position: absolute;
    top: 39px;
  }
}

@media only screen and (min-width: 1025px) {
  .toolbar-fixed:not(.toolbar-loading) .navbar.fixed-top {
    top: 39px !important;
  }

  .toolbar-fixed.toolbar-horizontal.toolbar-tray-open:not(.toolbar-loading) .navbar.fixed-top {
    top: 79px !important;
  }
}