Problem running jquery

Hello everyone!
I have problem running HTML code with java-script file that contains j query commands on my browsers, but it works perfectly on, i have tried all three browsers on my laptop (mozilla firefox, internet explorer and chrome) but the code is It didn’t work on any of them.
Can anyone help pls?

This my HTML code:

<!doctype html>

javascript basics
<style type="text/css">
		background-color: #50f;
		color: #fff;
		padding: 10px;
		font-size: 14pt;
		color: #fff;
		font-size: 25pt;

<button id="get">Get</button>
<button id="set">Set</button>
<button id="add">Add</button>
<button id="remove">Remove</button>
<button id="empty">Empty</button>
<div id="div_id" style="width: 300px; height: 200px; position: relative; background-color: #ccc;">
	<center> This is a div </center>
<input type="textbox_id" id="text_id" name="Enter Your Name" /> <br/><br/>

<select size="10" id="select_id"> 
	<option> Option #1 </option>
	<option> Option #1 </option>
	<option> Option #1 </option>

<ol id="list_id">
	<li> Item #1 </li>
	<li> Item #2 </li>
	<li> Item #3 </li>

Java-script file:

$(’#div_id’).addClass(‘class2’); // ‘#div_id’ <==> this // this will apply class2 on the div by clicking on it

	$('button').addClass('class1');		// this will apply class1 on the buttons by clicking on the div

	$('button').css({				// this will apply css elements to all buttons
		'color': 'red',
		'font-size': '30pt',
		'background-color': '#ccc'


I don’t see where you’ve told your HTML to load your .js files.

I have placed these tags in the head tag

I do not know why it does not appear in the comments box

Make sure you put three backticks ``` in the line above and the line below your code block
This is the link of the whole code on
Thanks for help

<script type="text/javascript" src="script.js"></script>
This is the line that will call your JS file.
So, on your computer, your index.html file needs to have this line, your .js file needs to be named script.js, and they need to be in the same folder.

Yes! I did all this but still not working.
I put the index.html beside the script.js in the same folder.
when i tried to replace the script.js content with something like: alert(‘test’) it’s works on the browser, but when i change the content to the jquery code, then it’s not work.

Try downloading the jQuery file and linking it to your HTML the same way. Call the file jquery.js

I already tired this solution and linked it on the head tag, but still not working
none of them works

Do you have these files in a GitHub repo?

At this point I’m at a loss without the ability to tweak the code files myself.

Which github repo files?

The files you’re currently having trouble getting to work

I downloaded them from

I meant your files. Gotta be able to see how your index.html, scripts.js, and jquery.js all fit together.