双图轮播

 let eleSwap=$('.introduction-aliyun')[0],
timerSwap=setInterval(func,6000),
currentPage=true;
function func(){
    if(currentPage){
        console.log(1)
        console.log(getComputedStyle(eleSwap).background)
        eleSwap.style.backgroundImage="url('/static/img/homepage/banner-bg-alibaba.png')";
    }else{
        console.log(2)
        console.log(getComputedStyle(eleSwap).background)
        eleSwap.style.backgroundImage="url('/static/img/homepage/ali-swap-bg.png')";
    }
    currentPage=!currentPage;
    }