Why CSS variables are used - Quick Recap

Recall & Review

beginner

What are CSS variables?

CSS variables are custom properties that store values you can reuse throughout your CSS. They start with two dashes, like --main-color.

beginner

How do CSS variables help with consistency?

By using CSS variables, you can define a value once and use it many times. This keeps colors, fonts, and sizes consistent across your website.

beginner

How do CSS variables make updating styles easier?

If you want to change a color or size, you only update the variable value once. All places using that variable update automatically.

intermediate

Can CSS variables be changed with JavaScript?

Yes! You can change CSS variables dynamically using JavaScript, which helps create interactive and responsive designs.

beginner

What is the syntax to use a CSS variable inside a style?

Use the var() function. For example, color: var(--main-color); applies the value of --main-color.

What is the main benefit of using CSS variables?

A They automatically fix broken CSS.

B They make CSS run faster in browsers.

C They replace HTML tags.

D They allow reusing values easily across styles.

CSS variables let you store values once and reuse them, making your styles consistent and easier to update.

How do you define a CSS variable?

A Using <code>variable-name: value;</code> in HTML.

B Using <code>$variable-name: value;</code> in CSS.

C Using <code>--variable-name: value;</code> inside a selector.

D Using <code>var(variable-name) = value;</code>.

CSS variables are defined with two dashes before the name inside a CSS selector, like --main-color: blue;.

Which function is used to access a CSS variable's value?

A getVar()

B var()

C useVar()

D fetchVar()

The var() function is used to get the value of a CSS variable, for example color: var(--main-color);.

Can CSS variables be changed after the page loads?

A Yes, with JavaScript.

B No, they are fixed.

C Only in Internet Explorer.

D Only by refreshing the page.

JavaScript can update CSS variables dynamically, allowing interactive style changes without reloading.

Why are CSS variables better than repeating the same value everywhere?

A They reduce errors and make updates easier.

B They make the page load slower.

C They only work in Chrome.

D They require special plugins.

Using variables avoids mistakes from typing values many times and lets you update styles quickly by changing one place.

Explain why CSS variables improve website style management.

Think about how changing one value can update many places.

Describe how CSS variables can be used with JavaScript.

Consider how websites change colors or themes on user actions.