<div>block</div>
<div class="small">width:80%</div>
<span>inline</span>
body{
  background: lightgray;
}
div{
  background: skyblue;
  border: 2px solid blue;
}
.small {
  width: 80%;
}
span{
  background: yellow;
  border: 2px solid orange;
}

External CSS

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External JavaScript

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