tools/side_chain_tool/web/node_modules/bootstrap/scss/mixins/_alert.scss

   1 @mixin alert-variant($background, $border, $color) {
   2   color: $color;
   3   @include gradient-bg($background);
   4   border-color: $border;
   5
   6   hr {
   7     border-top-color: darken($border, 5%);
   8   }
   9
  10   .alert-link {
  11     color: darken($color, 10%);
  12   }
  13 }