```
var a = document.createElement("div");
a.setAttribute("class", "jsonfiles");
document.getElementById("row").appendChild(a);

var a = document.createElement("div");
a.setAttribute("class", "jsonfiles");
document.getElementsByClassName("row").appendChild(a);

```

//with ID it works, but when I change the target itself (in html) to class and change the method in js code it doesnt??