Styling Your Next.js App
Add styles to a Next.js 15 application using global CSS, CSS Modules, and Tailwind CSS within the App Router.
Styling Your Next.js App is a free Next.js 15 Fullstack (App Router + Server Actions) lesson on CoddyKit — lesson 4 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Next.js 15 Fullstack (App Router + Server Actions) learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Styling Options Overview
Next.js supports several styling approaches out of the box: global CSS, scoped CSS Modules, utility-first Tailwind, and CSS-in-JS libraries.
Global Stylesheet
Global CSS is imported once in the root layout and applies to every page — ideal for resets and base typography.
import "./globals.css";
export default function RootLayout({ children }) {
return (<html lang="en"><body>{children}</body></html>);
}CSS Modules for Scope
A CSS Module (x.module.css) generates locally-scoped class names, so component styles never leak into each other.
import styles from "./button.module.css";
export default function Button() {
return <button className={styles.primary}>Click</button>;
}Inside the Module File
Inside a module you write class names normally — Next.js hashes them at build time to keep them unique.
.primary {
background: rebeccapurple;
color: white;
padding: 8px 16px;
}Tailwind CSS
Tailwind gives you utility classes you compose right in your markup. It's the most common styling choice in modern Next.js apps.
export default function Card() {
return <div className="rounded-lg bg-white p-4 shadow">Hello</div>;
}Setting Up Tailwind
To set up Tailwind, install it and add its three directives to your global stylesheet so the utility classes become available.
@tailwind base;
@tailwind components;
@tailwind utilities;Conditional Classes
Toggle classes by state for conditional styling. A helper like clsx keeps the logic clean and readable.
import clsx from "clsx";
<button className={clsx("btn", isActive && "btn-active")} />Fonts with next/font
The next/font module self-hosts fonts with zero layout shift and no extra request to a font provider — performant typography for free.
import { Inter } from "next/font/google";
const inter = Inter({ subsets: ["latin"] });Server vs Client Styling
Global CSS and CSS Modules work in Server Components. Some CSS-in-JS libraries need a Client Component boundary or special setup.
Responsive Design
Tailwind's responsive prefixes like md: and lg: apply styles at breakpoints, making mobile-first layouts effortless.
<div className="text-sm md:text-base lg:text-lg">Responsive text</div>Choosing an Approach
Pick by job: CSS Modules for component isolation, Tailwind for fast utility-driven UI, and global CSS for resets and base typography.
Quick Check
What does a CSS Module give you that a global stylesheet does not?
Recap
Recap: Next.js styling spans global CSS, scoped CSS Modules, and Tailwind utilities, plus next/font for fast type and responsive breakpoints.
Frequently asked questions
Is the “Styling Your Next.js App” lesson free?
Yes — the full text of “Styling Your Next.js App” is free to read here on the web, and the Next.js 15 Fullstack (App Router + Server Actions) course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Next.js 15 Fullstack (App Router + Server Actions) course, upgrade to CoddyKit PRO.
What will I learn in “Styling Your Next.js App”?
Add styles to a Next.js 15 application using global CSS, CSS Modules, and Tailwind CSS within the App Router. You practise Next.js 15 Fullstack (App Router + Server Actions) with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Next.js 15 Fullstack (App Router + Server Actions)?
No prior experience is required. Next.js 15 Fullstack (App Router + Server Actions) on CoddyKit is structured for beginners through advanced learners; this is — lesson 4 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Styling Your Next.js App” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Next.js 15 Fullstack (App Router + Server Actions) lesson?
Yes. Every Next.js 15 Fullstack (App Router + Server Actions) lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- Project Setup & CLI
- File-System Routing Basics
- Pages & Layouts Overview
- Styling Your Next.js App