Everyone is telling you this isn’t possible, perhaps because of their attention to precise semantics. No, you can’t literally make a background image clickable, since a background image isn’t an entity that can possess a behavioral property the way CSS is organized. But you can certainly apply a background image to a link, and without needing any transparent image overlays:
height: 100px; (height of the background image)
width: 200px; (width of the background image)
The anchor tag is naturally inline so you need to make it a block in order to hold a shape without inner content. The height & width are those of the image.
To make this work in a non-CSS user agent as well, you might want to add something like this:
Click my logo
If CSS isn’t enabled, the text link replace the image link.
Click here to see a good explanation of similar technics
Interactive Color Picker
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