(function(){
    'use strict';
    window.preloadFill.add('style', function(link, iframeDocument, iframeWindow, callback){
        var timer;
        var sheets = document.styleSheets;
        var preload = iframeDocument.createElement('link');
        var clear = function(){
            clearInterval(timer);
            preload.onload = null;
            preload.onerror = null;
            iframeDocument.documentElement.removeChild(preload);
        };
        var onload = function(){
            clear();
            callback('load');
        };
        preload.href = link.href;
        preload.rel = 'stylesheet';

        iframeDocument.documentElement.appendChild(preload);

        timer = setInterval(function(){
            var resolvedHref = preload.href;
            var i = sheets.length;
            while( i-- ){
                if( sheets[ i ].href == resolvedHref ){
                    onload();
                    break;
                }
            }
        }, 20);

        preload.onload = onload;
        preload.onerror = function(){
            clear();
            callback('error');
        };
    });
})();