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

Piotr Manczak
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Piotr Manczak
Front End Web Development Techdegree Graduate 28,940 Points

How to change background color using JavaScript

It doesn't work. It doesn't say why. Any ideas what I'm doing wrong?

app.js
var warning = document.getElementById("warning");
var button = document.getElementById('makeItRed');

button.addEventListener('click', () => {
  warning.style.background-color = "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

I believe background-color is what you'd use in CSS. In JavaScript it's backgroundColor.