javascript - getElementById() work in html file but not in js file

i cannot find answer to my question in someone else post so here it is:
getElementById return null in java script file (also while testing in console) but work in html file

HTML file

   

      
      
      

   
   

      
Some text

   

JS file

var title = document.getElementById('stuff');
console.log(title);
title.style.color = "#D4F34A";

Answer

You can add a callback function for the document event DOMContentLoaded event like so, and inside that function do your desired code:

//Add this into your script file, and anything you want to have execute once the document
//is fully loaded go inside of the function
document.addEventListener("DOMContentLoaded", function(event) {
    var title = document.getElementById('stuff');
    console.log(title);
    title.style.color = "#D4F34A";
});