// Full credit to Jeremy Keith http://adactio.com/journal/5429/
// Define breakpoints in css
/*
@media all and (max-width: 45em) {
    body:after {
        content: 'small';
        display: none;
    }
}
@media all and (min-width: 45em) {
    body:after {
        content: 'widescreen';
        display: none;
    }
}
*/

// Javascript detection of breakpoint
var size = window.getComputedStyle(document.body,':after').getPropertyValue('content');
if (size == 'widescreen') {
    // Load some more content
}