.fade {
  transition: $transition-fade;

  &:not(.show) {
    opacity: 0;
  }
}

// scss-docs-start collapse-classes
.collapse {
  &:not(.show) {
    display: none;
  }
}

.collapsing {
  height: 0;
  overflow: hidden;
  transition: $transition-collapse;
}
// scss-docs-end collapse-classes