Clearfix

Ensures that an element self-clears its children.

• Use the ::after pseudo-element and apply content: '' to allow it to affect layout.
• Use clear: both to make the element clear past both left and right floats.
• For this technique to work properly, make sure 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).
• Note: This is only useful if you are using float to build layouts. Consider using a more modern approach, such as the flexbox or grid layout.

<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;
  padding: 4px;
}