:before Element On Top of Background but Behind Text

May 10, 2020

Sometimes you have content in a before element that you want to appear on top of a background image but behind other elements on the page. In my situation I had an image with a css triangle used as a mask over the image but wanted text to be able to appear on top of the triangle.

The image below shows what I was going for. There is a white triangle masking the image and the text is visible on top of the triangle even though it is position absolute. The key here is making sure the :before element has z-index: 0 and any of the text elements are either in a flex container or have position: relative with z-index: 1.

<div class="body-wrapper">
  <h1 class="heading">@itwasmattgregg</h1>
</div>

.body-wrapper {
  background-image: url('https://codegregg.com/images/matt.jpg');
  background-size: contain;
  background-position: right;
  background-repeat: no-repeat;
  height: 600px;
  position: relative;
}

.body-wrapper::before {
  content: '';
  position: absolute;
  top: 0;
  height: 0;
  width: 0;
  z-index: 0;
  right: 440px;
  border-top: 600px solid #fff;
  border-right: 160px solid transparent;
}

.heading {
  z-index: 1;
  position: relative;
}