function fn1(){
    $('#sidebar').animate({
        left:'-20%'
    },"fast");
    $('#groundglass').animate({
        left:'-20%'
    },"fast");
}
function fn2() {
    $('#sidebar').animate({
        left:'1%'
    },"fast");
    $('#groundglass').animate({
        left:'1%'
    },"fast");
}
function btnHide() {
    var obj = $('#btnhide');
    var tt = obj.html();
    if (tt =='隐藏'){
        obj.html('展示');
        fn1();
    }else if(tt == '展示'){
        obj.html('隐藏');
        fn2();
    }

}