First, please take a look at the page below.
The slider on the left side has dark filters on the top and the bottom. Here's the code of the slider that I found from the developer tool.
<div class="fs_gallery_slider" data-thumbs-btn-title="Thumbs">
::before
::after
</div>
As you can see, the top filter and the bottom filter are both generated with pseudo-elements. They're both displayed in HTML when the window size is over 1024px, and not when the window size is below 1024px. I thought they were controlled with some CSS property such as "display:none;", but media queries are not being used for them, so that seems like not the case.
In this case, does it mean these pseudo-elements are generated with JavaScript or some way? If so, is there a way to find the source?
Thank you.