First time using js's DOM, can u guys help me why does this code have a mistake? + rewrite the correct syntax

Question

https://code.sololearn.com/WYvG5X9mgj5L/?ref=app

Answer 1

Is it this that you wanted?
https://code.sololearn.com/WAyBAnM3Xus1/?ref=app

Answer 2

The problem is that (in your case) js is loaded before your html element and, because you try to access to an element in your js code, you will get a null reference... Read run and follow execution of this code and you will understand
https://code.sololearn.com/WlA8Fx8bl6nI/?ref=app

Answer 3

Thx for your "enlightenment", Rstar :)