Use CSS to make background-image above background-color in a list

Question

This is the code

<ul>
    <li class="test">
         <a href="#">
            <h2>Blah</h2>
            <p>Blah Blah Blah</p>
         </a>
    </li>
</ul>

Basically, my list already has some styling, for example, I set the background-color for it.

Now in the class "test", I also set a background-image.

My question is I want to make the background-image stays above the background-color and I dont know how to achieve this. I tried with z-index but I think it is not applicable for background-image.

Please take a look at the image

Edit: This is the CSS Code

For example, this is the styling for my list

#sidebar ul li{  
    background:#ccf;
}

And this is the styling for the class test

.test{
    background-image: url('img/big_tick.png');
    background-repeat:no-repeat;
    background-position: bottom right;
    -moz-background-size: 30%;
    -webkit-background-size: 30%;
    background-size: 30%;    
    margin-right: 30px;
}

Answer 1

Add the !important attribute to your background-image. Like this:

.test a{
background-image: url('img/big_tick.png') !important;
background-repeat:no-repeat;
background-position: bottom right;
-moz-background-size: 30%;
-webkit-background-size: 30%;
background-size: 30%;    
margin-right: 30px;

}

I have an example fiddle here

EDIT: I changed the class to .test a to reflect the actual styling scheme