Overlay a background-image with an rgba background-color

Question

The solution by PeterVR has the disadvantage that the additional color displays on top of the entire HTML block - meaning that it also shows up on top of div content, not just on top of the background image. This is fine if your div is empty, but if it is not using a linear gradient might be a better solution:

<div class="the-div">Red text</div>

<style type="text/css">
  .the-div
  {
    background-image: url("the-image.png");
    color: #f00;
    margin: 10px;
    width: 200px;
    height: 80px;
  }
  .the-div:hover
  {
    background-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
    background-image: -moz-linear-gradient(top, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
    background-image: -o-linear-gradient(top, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
    background-image: -ms-linear-gradient(top, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
    background-image: -webkit-gradient(linear, left top, left bottom, from(rgba(0, 0, 0, 0.1)), to(rgba(0, 0, 0, 0.1))), url("the-image.png");
    background-image: -webkit-linear-gradient(top, rgba(0, 0, 0, 0.1), rgba(0, 0, 0, 0.1)), url("the-image.png");
  }
</style>

See fiddle. Too bad that gradient specifications are currently a mess. See compatibility table, the code above should work in any browser with a noteworthy market share - with the exception of MSIE 9.0 and older.

Edit (March 2017): The state of the web got far less messy by now. So the linear-gradient (supported by Firefox and Internet Explorer) and -webkit-linear-gradient (supported by Chrome, Opera and Safari) lines are sufficient, additional prefixed versions are no longer necessary.

Yes, there is a way to do this. You could use a pseudo-element after to position a block on top of your background image. Something like this: http://jsfiddle.net/Pevara/N2U6B/

The css for the :after looks like this:

#the-div:hover:after {
    content: ' ';
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    background-color: rgba(0,0,0,.5);
}

edit:
When you want to apply this to a non-empty element, and just get the overlay on the background, you can do so by applying a positive z-index to the element, and a negative one to the :after. Something like this:

#the-div {
    ...
    z-index: 1;
}
#the-div:hover:after {
    ...
    z-index: -1;
}

And the updated fiddle: http://jsfiddle.net/N2U6B/255/

/* Working method */
.tinted-image {
  background: 
    /* top, transparent red, faked with gradient */ 
    linear-gradient(
      rgba(255, 0, 0, 0.45), 
      rgba(255, 0, 0, 0.45)
    ),
    /* bottom, image */
    url(https://upload.wikimedia.org/wikipedia/commons/7/73/Lion_waiting_in_Namibia.jpg);
    height: 1280px;
    width: 960px;
    background-size: cover;
}

.tinted-image p {
    color: #fff;
    padding: 100px;
  }

<div class="tinted-image">
  
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Laboriosam distinctio, temporibus tempora a eveniet quas  qui veritatis sunt perferendis harum!</p>
  
</div>

source: https://css-tricks.com/tinted-images-multiple-backgrounds/

Ideally the background property would allow us to layer various backgrounds similar to the background image layering detailed at http://www.css3.info/preview/multiple-backgrounds/. Unfortunately, at least in Chrome (40.0.2214.115), adding an rgba background alongside a url() image background seems to break the property.

The solution I've found is to render the rgba layer as a 1px*1px Base64 encoded image and inline it.

.the-div:hover {
  background-image:url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNgkAQAABwAGkn5GOoAAAAASUVORK5CYII=), url("the-image.png");
}

for base64 encoded 1*1 pixel images I used http://px64.net/

Here is your jsfiddle with these changes made. http://jsfiddle.net/325Ft/49/ (I also swapped the image to one that still exists on the internet)

I've gotten the following to work:

html {
  background:
      linear-gradient(rgba(0,184,255,0.45),rgba(0,184,255,0.45)),
      url('bgimage.jpg') no-repeat center center fixed;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}

The above will produce a nice opaque blue overlay.