qsa-polyfill-ie7.js

if (!document.querySelectorAll) {
    document.querySelectorAll = function(selector) {
        var doc = document,
            head = doc.documentElement.firstChild,
            styleTag = doc.createElement('STYLE');
        head.appendChild(styleTag);
        doc.__qsaels = [];

        styleTag.styleSheet.cssText = selector + "{x:expression(document.__qsaels.push(this))}";
        window.scrollBy(0, 0);

        return doc.__qsaels;
    }
}

qsa-polyfill-ie7.min.js

document.querySelectorAll||(document.querySelectorAll=function(a){var b=document,c=b.documentElement.firstChild,d=b.createElement("STYLE");return c.appendChild(d),b.__qsaels=[],d.styleSheet.cssText=a+"{x:expression(document.__qsaels.push(this))}",window.scrollBy(0,0),b.__qsaels});