Print part of the screen based on a CSS selector

printPartialScreen.js

function print(selector) {
    var w = window.open('', '', 'left=0,top=0,width=' + window.width + ',height=' + window.height + ',toolbar=0,scrollbars=0,status=0');
    w.document.write('<link rel="stylesheet" type="text/css" href="/path/to.css" />');
    w.document.write(document.querySelector(selector).innerHTML);
    w.document.close();
    w.addEventListener('load', function () {
        w.focus();
        w.print();
        w.close();
    }, true);
}

Probably should update this to automatically pull in all the stylesheets from the existing page.