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JavaScript JavaScript and the DOM (Retiring) Responding to User Interaction Adding an Event Listener

my head is up side down

i cant find the problem

app.js
const warning = document.getElementById("warning");
let button = document.querySelector("#makeItRed");
button.addEventListener('click' , () => {

 warning.style.backgroundcolor = "red"});
index.html
<!DOCTYPE html>
<html>
    <head>
        <title>Adding an Event Listener</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <div id="warning">
            Warning: My background should be red!
        </div>
        <button id="makeItRed">Make It Red!</button>
        <script src="app.js"></script>
    </body>
</html>

2 Answers

Steven Parker
Steven Parker
229,644 Points

In JavaScript, CSS style property names use camel case.

So where you have "backgroundcolor", it should be "backgroundColor" (with a capital "C").

thank you very much

Here is the answer to those questions:

const warning = document.getElementById("warning");
let button = document.getElementById("makeItRed");

button.addEventListener('click', () => {
       warning.style.backgroundColor = "red";
  });

thanks!