Why Doesn't `:first-child` Select My H1?

Why :first-child Doesn't Select the Expected H1

In the scenario presented, the goal is to color the first h1 element within a div with the class detail_container blue. The CSS used (:first-child) assumes that the targeted element is the first child of its parent, but in this case, the parent's first child is the ul element.

Understanding :first-child

The :first-child selector selects the first child element of a specified parent element that matches the specified criteria. In the provided code, the criteria is "h1," but because the first child of the div is the ul, the :first-child selector does not apply to the h1 element.

Alternative Solution Using :first-of-type

CSS3 introduces the :first-of-type selector, which selects the first occurrence of an element type within its parent. In this scenario, replacing :first-child with :first-of-type would resolve the issue:

.detail_container h1:first-of-type {
  color: blue;
}

Browser Compatibility Considerations

However, :first-of-type has limited browser compatibility compared to :first-child.

Recommended Solution Using Class

A more practical and cross-browser compatible solution is to assign a class to the targeted h1 element and style it accordingly:

.detail_container h1.first {
  color: blue;
}

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