Cookie

    $(".theme-colors > li > span").hover(function(e) {
        var t = $(this),
        n = $("body");
        n.attr("class", "").addClass("theme-" + t.attr("class"));
    },
    function() {
        var e = $(this),
        t = $("body");
        t.attr("data-theme") !== undefined ? t.attr("class", "").addClass(t.attr("data-theme")) : t.attr("class", "")
    }).click(function() {
        var e = $(this);
        $("body").addClass("theme-" + e.attr("class")).attr("data-theme", "theme-" + e.attr("class"));
        addCookie('text_class', e.attr("class"), 86400 * 30);
    });
/cookie 开始/
var addCookie = function(objName, objValue, objHours) {
        var str = objName + "=" + escape(objValue);
        if (objHours > 0) {
            var date = new Date();
            var ms = objHours * 3600 * 1000 * 24;
            date.setTime(date.getTime() + ms);
            str += ";path=/; expires=" + date.toGMTString();
        }
        document.cookie = str;
    },
    getCookie = function(objName) {
        var arrStr = document.cookie.split("; ");
        for (var i = 0; i < arrStr.length; i++) {
            var temp = arrStr[i].split("=");
            if (temp[0] == objName) return unescape(temp[1]);
        }
    },
    class_ = getCookie('text_class');
    class_ && $("body").addClass("theme-" + class_).attr("data-theme", "theme-" + class_);

/cookie 结束/



原本
可以更换样式的名称 
或者是一个样式一个css文件 ，到时候更换 css文件即可。 
cookie 操作类 100%可用

/////------------------------js cookie操作类-------------------begin   [edit by ygd]
function addCookie(objName, objValue, objHours) {//添加cookie
    var str = objName + "=" + escape(objValue);
    if (objHours > 0) {//为0时不设定过期时间，浏览器关闭时cookie自动消失
        var date = new Date();
        var ms = objHours * 3600 * 1000 * 24;
        date.setTime(date.getTime() + ms);
        str += "; expires=" + date.toGMTString();
    }
    document.cookie = str;
}
function getCookie(objName) {//获取指定名称的cookie的值
    var arrStr = document.cookie.split("; ");
    for (var i = 0; i < arrStr.length; i++) {
        var temp = arrStr[i].split("=");
        if (temp[0] == objName) return unescape(temp[1]);
    }
}
/////------------------------js cookie操作类-------------------end