Modern JavaScript from the Beginning - Second Edition - Manipulating Styles and Classes

The video tutorial covers manipulating CSS classes and styles using JavaScript. It begins with an introduction to CSS class manipulation, followed by setting up HTML elements with specific classes. The tutorial then demonstrates using JavaScript to select elements, set up events, and manipulate classes using the className property and classList methods. It concludes with direct style manipulation using JavaScript, showcasing how to dynamically change styles and classes in response to events.

What is the primary reason for using JavaScript to manipulate CSS classes?

• To simplify the HTML structure

• To enable dynamic functionality based on user interactions

• To add static styles to elements

• To change styles when the page loads

Which method is used to select a single element by its class in JavaScript?

• querySelectorAll

• getElementsByClassName

• querySelector

• getElementById

What happens when you set a new class name using the className property?

• It toggles the new class on and off

• It removes all existing classes and sets the new class

• It only affects inline styles

• It appends the new class to existing classes

Which method allows you to add a class without removing existing classes?

• className

• addClass

• setClass

• classList.add

How can you toggle a class on and off using JavaScript?

• Using classList.remove

• Using classList.add

• Using classList.toggle

• Using className

What is the purpose of the replace method in classList?

• To toggle a class

• To replace one class with another

• To remove a class

• To add a new class

How do you change the style of an element directly using JavaScript?

• Using setAttribute

• Using the style property

• Using classList

• Using className