cartodb/assets/stylesheets/editor-3/_disable-overlay.scss

.Disable-overlay {
  position: absolute;
  z-index: 100;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  background: rgba(#FFF, 0.6);

  &.is-hidden {
    display: none;
  }
}