Clearfix

Ensures that an element self-clears its children.

<div class="clearfix">
  <div class="floated">float a</div>
  <div class="floated">float b</div>
  <div class="floated">float c</div>
</div>

.clearfix::after {
  content: '';
  display: block;
  clear: both;
}

.floated {
  float: left;
}

Explanation

1. .clearfix::after defines a pseudo-element.
2. content: '' allows the pseudo-element to affect layout.
3. clear: both indicates that the left, right or both sides of the element cannot be adjacent to earlier floated elements within the same block formatting context.

Note: This is only useful if you are still using float to build layouts. Please consider using a modern approach with flexbox layout or grid layout.

Browser support

⚠️ For this snippet to work properly you need to ensure that there are no non-floating children in the container and that there are no tall floats before the clearfixed container but in the same formatting context (e.g. floated columns).