I finally did this.
You put both pages inside the one page.
The two contents go to separate divs.
Then you use something like this code:
<script>
document.querySelector('.div2').style.display = "none";
document.querySelector('form').addEventListener("submit", function(e){
document.querySelector('.div1').style.display = "none";
document.querySelector('.div2').style.display = "block";
});
</script>
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…