How do I remove background-image in css?

I have a general rule which gives all DIVs a background image.
I have one div (with id='a') which I don't want it to have the background image.
What css rule do I have to give it?

Try:

div#a {
    background-image:none
}

div#a {
    background-image: none;
}

div#a {
  background-image: none !important;
}

Although the "!important" might not be necessary, because "div#a" has a higher specificity than just "div".

div#a {
  background-image: url('../images/spacer.png');
  background-image: none !important;
}

I use a transparent spacer image in addition to the rule to remove the background image because IE6 seems to ignore the background-image: none even though it is marked !important.

Since in css3 one might set multiple background images setting "none" will only create a new layer and hide nothing.

http://www.css3.info/preview/multiple-backgrounds/ http://www.w3.org/TR/css3-background/#backgrounds

I have not found a solution yet...

When background-image: none !important; have no effect. You can use:

background-size: 0 !important;

background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0, #fff), color-stop(0.5, #fff));
background-image: -webkit-linear-gradient(center top, #fff 0%, #fff 50%);
background-image: -moz-linear-gradient(center top, #fff 0%, #fff 50%);
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffffff', endColorstr='#ffffff', GradientType=0);
background-image: linear-gradient(to bottom, #fff 0%, #fff 50%);

for older browsers.. if you have defined css in some framewokrk.css like select2.css in IE9 background-image: -webkit-gradient etc. and you want it via another .css rewrite with "background-image: none !important" not works. I used same color to color gradient like page background color.

If your div rule is just div {...}, then #a {...} will be sufficient. If it is more complicated, you need a "more specific" selector, as defined by the CSS specification on specificity. (#a being more specific than div is just single aspect in the algorithm.)

Doesn't this work:

.clear-background{
background-image: none;
}

Might have problems on older browsers...

Replace the rule you have with the following:

div:not(#a) { // add your bg image here //}

HTML :

<div id="a" class="mydiv"></div>    

CSS:

div#a {
       background-image:none;
}

Another Way:

div:not(#a) {
     //all rules goes here 
     //add image here
     //div with id a not effected by these rules
   }

Multiple (not pseudo)

   div:not(#a):not(#b):not(#c) {
     //all rules goes here 
     //add image here
     //div with ids not effected with these rules
   }