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<meta name="viewport" content="width=device-width">

<h1>Composable CSS with @apply</h1>

<p>This demo requires a very new version of Chromium. See the original blog post at <a href="http://zeke.sikelianos.com/css-from-the-future">zeke.sikelianos.com/css-from-the-future</a>

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  <strong>Well done!</strong> You successfully read this important alert message.

<div class="alert alert-warning">
  <strong>Warning!</strong> Better check yourself, you're not looking too good.
              body {
  font-family: 'helvetica neue', helvetica, sans-serif;
  padding: 2rem;
  --alert: {
    color: white;
    padding: 15px;
    margin: 1rem 0;
    border-radius: 6px;

.alert-success {
  @apply --alert;
  background-color: olivedrab;

.alert-warning {
  @apply --alert;
  background-color: firebrick;
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