How to re-create entire div with createElement()

For now, I dont care where the box shows up on the screen, I just want to press the Run button and re-create the first box.

I don't know what I can do for the entire box to be replicated.

Demo

 document.getElementById("btn").onclick = function () {
var ok = true;

 if (ok === true) {
      var obj = document.createElement('div');
      obj.className = 'box';
   document.getElementsByTagName('body')[0].appendChild(obj);
}
}

Solved

Will this JSfiddle work for you?

number = 0; //The index for the first div

document.getElementById("btn").onclick = function() {
  var ok = true;
  boxHTML = document.getElementsByClassName("box")[number].innerHTML;
  //Get innerHTML of the last box: "getElementsByClassName" returns an
  //array and the brackets contain a number that detemines which value
  //to be selected.

  number++; //Increment number

  if (ok === true) {
    var obj = document.createElement('div');
    obj.className = 'box box-' + number; //add class with number tag
    obj.innerHTML = boxHTML; //Give object same HTML
    document.getElementsByTagName('body')[0].appendChild(obj);
  }
};

//Boxes
@import url(https://fonts.googleapis.com/css?family=Roboto:400,700);
html,
* {
  box-sizing: border-box;
}

body {
  background: #e4e9f0;
  padding: 40px;
}

.box {
  float: left;
  position: relative;
  display: inline-block;
  width: 45%;
  background: white;
  padding: 30px;
  margin-right: 2%;
  margin-left: 4%;
  margin-top: 3%;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  border-radius: 2px;
  overflow: hidden;
  +.box {
    margin: 0px;
    margin-top: 3%;
  }
  &:after {
    padding-top: 30%;
    /* 16:9 ratio */
    display: block;
    content: '';
  }
  >div {
    float: left;
    width: 100%;
    height: 150px;
    color: #fff;
  }
  header {
    background: #533687;
    display: block;
    margin: -30px -30px 30px -30px;
    padding: 10px 10px;
    h2 {
      line-height: 1;
      padding: 0;
      margin: 0;
      font-family: "roboto", sans-serif;
      font-weight: 600;
      font-size: 20px;
      color: white;
      -webkit-font-smoothing: antialiased;
    }
  }
}

  
    

      
Responsive C3
    
    

    
  

Note: If you use jQuery, things could be a lot easier.