main.js

var element = document.getElementById("placeholder_one");

function floatdiv_load() {
  element.innerHTML = "<div id='floatdiv'>Username/Email<input type='text' formaction='' />Password<input type='password' formaction='' /></div>";
  document.getElementById("login-button").onclick = "floatdiv_unload" ;
}

function floatdiv_unload() {
  element.innerHTML = " ";
  document.getElementById("login-button").onclick = floatdiv_load ;
}