Styling a disabled checkbox directly is not possible as it is controlled by the browser / OS.
However, there is a clever workaround where you can replace the checkbox with a label that mimics a checkbox using pure CSS. By utilizing an adjacent label, you can create a new "pseudo checkbox" and have complete control over its appearance in any state.
An example demonstrating this technique can be found here: http://jsfiddle.net/JohnSReid/pr9Lx5th/3/
Below is the sample code:
input[type="checkbox"] {
display: none;
}
label:before {
background: linear-gradient(to bottom, #fff 0px, #e6e6e6 100%) repeat scroll 0 0 rgba(0, 0, 0, 0);
border: 1px solid #035f8f;
height: 36px;
width: 36px;
display: block;
cursor: pointer;
}
input[type="checkbox"] + label:before {
content: '';
background: linear-gradient(to bottom, #e6e6e6 0px, #fff 100%) repeat scroll 0 0 rgba(0, 0, 0, 0);
border-color: #3d9000;
color: #96be0a;
font-size: 38px;
line-height: 35px;
text-align: center;
}
input[type="checkbox"]:disabled + label:before {
border-color: #eee;
color: #ccc;
background: linear-gradient(to top, #e6e6e6 0px, #fff 100%) repeat scroll 0 0 rgba(0, 0, 0, 0);
}
input[type="checkbox"]:checked + label:before {
content: '✓';
}
<div><input id="cb1" type="checkbox" disabled checked /><label for="cb1"></label></div>
<div><input id="cb2" type="checkbox" disabled /><label for="cb2"></label></div>
<div><input id="cb3" type="checkbox" checked /><label for="cb3"></label></div>
<div><input id="cb4" type="checkbox" /><label for="cb4"></label></div>
Depending on browser compatibility and accessibility requirements, additional adjustments may be necessary.