var getElementsByClassName = document.getElementsByClassName ? function (className, scope) {
        return Array.prototype.slice.call((scope || document).getElementsByClassName(className));
    } : document.evaluate ? function (className, scope) {
        scope = scope || document;
        var re = [], xpathResult, ele;
        var scopeDocument    = !scope.ownerDocument ? scope : scope.ownerDocument;
        var searchClassNames = getElementsByClassName.__quirksCheck(className.trim(), scope).split(" ");
        var searchClassName  = searchClassNames[0];
        var searchClassNameLength = searchClassNames.length;

        if (scopeDocument.compatMode == "BackCompat") {
            xpathResult = scopeDocument.evaluate(".//*[contains(concat(' ', translate(@class, 'ABCDEFGHIJKLMNOPQRSTUVWYXZ', 'abcdefghijklmnopqrstuvwyxz'), ' '), ' " + searchClassName + " ')]", scope, null, 0, null);
        } else {
            xpathResult = scopeDocument.evaluate(".//*[contains(concat(' ', @class, ' '), ' " + searchClassName + " ')]", scope, null, 0, null);
        }

        if (searchClassNameLength > 1) {
            var eleClassNames, classNameLength;
            while ((ele = xpathResult.iterateNext())) {
                classNameLength = 1;
                eleClassNames = getElementsByClassName.__quirksCheck(ele.className, scope).split(" ");
                check: for (var i = 1; searchClassName = searchClassNames[i]; i++) {
                    if (eleClassNames.indexOf(searchClassName) > -1) {
                        classNameLength++;
                        if (classNameLength == searchClassNameLength) {
                            re.push(ele);
                            break check;
                        }
                    }
                }
            }
        } else {
            while ((ele = xpathResult.iterateNext())) {
                re.push(ele);
            }
        }

        return re;
    } : function (className, scope) {
        scope = scope || document;
        var re = [], ele, eleClassNames;
        var elements = scope.getElementsByTagName("*");
        var searchClassNames = getElementsByClassName.__quirksCheck(className.trim(), scope).split(" ");
        var searchClassName  = searchClassNames[0];
        var searchClassNameLength = searchClassNames.length;

        if (searchClassNameLength > 1) {
            var classNameLength;
            for (var i = 0; ele = elements[i]; i++) {
                eleClassNames = getElementsByClassName.__quirksCheck(ele.className, scope).split(" ");
                classNameLength = 0;
                check: for (var j = 0; searchClassName = searchClassNames[j]; j++) {
                    if (eleClassNames.indexOf(searchClassName) > -1) {
                        classNameLength++;
                        if (classNameLength == searchClassNameLength) {
                            re.push(ele);
                            break check;
                        }
                    }
                }
            }
        } else {
            for (var i = 0; ele = elements[i]; i++) {
                eleClassNames = getElementsByClassName.__quirksCheck(ele.className, scope).split(" ");
                if (eleClassNames.indexOf(searchClassName) > -1) {
                    re.push(ele);
                }
            }
        }

        return re;
    };
getElementsByClassName.__quirksCheck = function (className, scope) {
    return (!scope.ownerDocument ? scope : scope.ownerDocument).compatMode == "BackCompat" ? className.toLowerCase() : className;
}

if (typeof Array.prototype.indexOf == "undefined") {
    Array.prototype.indexOf = function (val) {
        for (var i = 0, ele; ele = this[i]; i++)
            if (ele === val)
                return i;
        return -1;
    }
}
if (typeof String.prototype.trim == "undefined") {
    String.prototype.trim = function() {
        var str = this.replace(/^\s\s*/, ''), ws = /\s/, i = str.length;
        while (ws.test(str.charAt(--i)));
        return str.slice(0, i + 1);
    }
}