gistfile1.js

function both(cssURLs, jsURLs, callback) {
  var cssDone, jsDone;

  function finish() {
    if (cssDone && jsDone) {
      callback();
    }
  }

  LazyLoad.css(cssURLs, function () { cssDone = 1; finish(); });
  LazyLoad.js(jsURLs, function () { jsDone = 1; finish(); });
}