message: Tweak the color of checkboxes for the disabled state.
diff: @@ -82,7 +82,11 @@ input[type="checkbox"] {
  transition: background-color .16s cubic-bezier(0.5, 0.15, 0.2, 1);
  &:focus {
  - box-shadow: 0 0 0 1px $base-border-color;
  + background-color: $component-background-color;
  + }
  +
  + &:disabled {
  + background-color: $level-1-color;
  }
  &:active {
  @@ -119,6 +123,10 @@ input[type="checkbox"] {
  &:active {
  background-color: $text-color-subtle;
  }
  + &:disabled {
  + background-color: $level-1-color;
  + }
  +
  &::before,
  &::after {
  opacity: 1;
  