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William Yeung
William Yeung
11,331 Points

Extended Element

Does the class being extended need to be present in the HTML? Or can you just create it in the SCSS file? Because here, I don't see .btn in the HTML anywhere.

1 Answer

Jamie Reardon
.a{fill-rule:evenodd;}techdegree seal-36
Jamie Reardon
Treehouse Project Reviewer

When you create an extend with a class name, and you include the extend directive with other css rules, you will be outputting that class name from the extend with those rules. It is better to create a placeholder instead so that you don't have to make these classes in your markup.

A good example of a placeholder extend is a clearfix. A placeholder is declared by using the % sign followed by the name:

%clearfix {
  content: '';
  display: table:
  clear: both;

.selector {
  @extend %clearfix;

.selector-2 {
  @extend %clearfix;

Using this method has the advantage of not needing to make a class for the clearfix.