自定义轮播

var timer=setInterval(changeBg,5000);

function changeBg(){

var bg=$(".login-bg").css("background-image");
var params = bg.split('"');
var param = params[1].split("/");
var img = param[param.length-1].split(".")[0];
if(img=="main_bg"){
$(".login-bg").css('background-image','url("class/images/main_bg2.png")');
$(".zs").css('background','rgba(0, 0, 0, 0.6)');
}else if(img=="main_bg2"){
$(".login-bg").css('background-image','url("class/images/main_bg3.png")');
$(".zs").css('background','rgba(0, 0, 0, 0.6)');
}else if(img=="main_bg3"){
$(".login-bg").css('background-image','url("class/images/main_bg.png")');
$(".zs").css('background','rgba(0, 0, 0, 0.6)');
}
}