<div class="block-so-tall-you-need-to-scroll">
    <div class="groovy-block"></div>
</div>

body {
  margin: 0;
}
.block-so-tall-you-need-to-scroll {
  height:200vh;
  background: #2C3E50;
}
.groovy-block {
  background: #E74C3C;
  height: 50px;
  width: 100vw;
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

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