I have a box overlayed on a background image. The overlay container has an image. When the image is placed on top of the overlay, the image is made transparent to the same opacity of the overlay. I've tried to use w3-opacity-0 to correct this, without success.
You can view the page in question here: https://bonus.udll.com (left dark box, look at the picture of the free chapter)>
<div class="w3-cell w3-margin-0 w3-black w3-opacity-min w3-text-white w3-padding-large w3-mobile w3-center block-width">