To achieve a "foreground image" (without extra HTML code), you can use a pseudo-element (::before
/ :before
) plus the CSS pointer-events
. The last property is needed so that the user can actually click through the layer "as if it did not exist".
Here's an example (using a colour whose alpha channel is 50% so that you can see that the real elements can actually be focused). http://jsfiddle.net/JxNdT/
?<div id="cont">
Test<br>
<input type="text" placeholder="edit">
</div>??????????????????????????????????????????????????????
?#cont {
? ? width: 200px;
? ? height: 200px;
? ? border: 1px solid #aaa; /*To show the boundaries of the element*/
}
#cont:before?{
? ? position: absolute;
? ? content: '';
? ? background: rgba(0,0,0, 0.5); /*partially transparent image*/
? ? width: 200px;
? ? height: 200px;
? ? pointer-events: none;
}
?
PS. I picked the ::before
pseudo-element, because that naturally leads to the correct positioning. If I pick ::after
, then I have to add position:relative;
to the real element (#cont
), and top:0;left:0;
to the pseudo-element (::after
).
PPS. To get the foreground effect on elements without a fixed size, an additional element is needed. This wrapper element requires the position:relative;display:inline-block;
styles. Set the width
and height
of the pseudo-element to 100%
, and the pseudo-element will stretch to the width and height of the wrapper element. Demo: http://jsfiddle.net/JxNdT/1/.
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