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Bootstrap class: .text-white-50

<p class="text-white-50 bg-danger">I'm a text with 50% opacity white</p>

Preview

I'm a text with 50% opacity white

Sass source

/* _text.scss:52 */
.text-white-50 { color: rgba($white, .5) !important; }

// Misc

.text-hide {
  @include text-hide($ignore-warning: true);
}

Uses variables

/* _text.scss:52 */
$white
$ignore-warning: