How to Fix CSS Not Applying in Your React App

Struggling with CSS not applying in React? This guide walks you through fixing your styles and ensuring they render correctly in your app.
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This video is based on the question stackoverflow.com/q/74980488/ asked by the user 'Han Qin' ( stackoverflow.com/u/13370954/ ) and on the answer stackoverflow.com/a/74980630/ provided by the user 'FocusCookie' ( stackoverflow.com/u/6280925/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

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How to Fix CSS Not Applying in Your React App: A Step-by-Step Guide

When you’re developing a React application, it can be frustrating to see your meticulously crafted styles not applying as expected. You might have followed along with a guide, imported your CSS correctly, and yet, nothing seems to happen when you run your app. If this situation sounds familiar, you're not alone!

In this post, we’ll break down common issues related to CSS not applying in React and provide clear, step-by-step solutions. Let’s dive into it!

Understanding the Problem

Suppose you’ve copied CSS from a guide into your index.css file in React, but it's not showing up in your app. Here’s a brief overview of what could be going awry:

Import Placement: It might be that you're not importing your CSS file correctly in your components.

CSS File Location: The location of your index.css file can influence whether it gets recognized.

React Case Sensitivity: React is case sensitive, and issues might arise due to casing errors in the class names.

Solution: Step-By-Step Guide

1. Importing CSS in the Right Place

First and foremost, ensure that your index.css file is imported in the correct location. Here’s what you should do:

Only Import in index.js: Make sure you're importing your index.css file in index.js, and remove any other imports from App.js. Here’s how it should look:

[[See Video to Reveal this Text or Code Snippet]]

2. Checking File Location and Path

Next, check that the index.css file is in the same folder as your index.js file, typically the src folder. Ensure you're using the correct relative path when importing:

[[See Video to Reveal this Text or Code Snippet]]

3. Looking for Case Sensitivity Issues

In your App.js, when you apply class names or IDs to your elements, make sure they exactly match the styles you've defined in your CSS. For example, in your App.js:

You used className="Container" but in your CSS, it's defined as .container (with a lowercase 'c'). React treats these as different names. Make sure to use the same casing in your JSX as defined in your CSS.

Updated App.js code:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By following these steps, you should be able to solve the issue of CSS not applying in your React app. Remember to:

Ensure your CSS file is imported only in index.js.

Check that the file path is correct.

Match the class names and IDs exactly in terms of casing.

With these adjustments, your styles should render beautifully in your application, enhancing your user interface effectively. Happy coding!