Quickstart: Preact

1 Initialize project

npm create vite@latest css-hooks-playground -- --template preact-ts
cd css-hooks-playground
npm install && npm install @css-hooks/preact

2 Start dev server

npm run dev

Visit http://localhost:5173 to view changes in real time.

3 Set up CSS Hooks

Create a src/css.ts module with the following contents:

import { createHooks } from "@css-hooks/preact";

export const { styleSheet, css } = createHooks({
  hooks: {
    "&:active": "&:active",
  },
  debug: import.meta.env.DEV,
});

4 Add style sheet

Modify src/main.tsx to add the style sheet to the document:

import { render } from 'preact'
import { App } from './app.tsx'
import './index.css'
import { styleSheet } from './css.ts'

render(<App />, document.getElementById('app')!)
render(
  <>
    <style dangerouslySetInnerHTML={{ __html: styleSheet() }} />
    <App />
  </>,
  document.getElementById('app')!
)

5 Add conditional style

Use the configured &:active hook to implement an effect when the counter button is pressed:

// src/app.tsx

import { useState } from 'preact/hooks'
import preactLogo from './assets/preact.svg'
import viteLogo from '/vite.svg'
import './app.css'
import { css } from './css.ts'

export function App() {
  const [count, setCount] = useState(0)

  return (
    <>
      <div>
        <a href="https://vitejs.dev" target="_blank">
          <img src={viteLogo} className="logo" alt="Vite logo" />
        </a>
        <a href="https://preactjs.com" target="_blank">
          <img src={preactLogo} className="logo preact" alt="Preact logo" />
        </a>
      </div>
      <h1>Vite + Preact</h1>
      <div className="card">
        <button onClick={() => setCount((count) => count + 1)}>
        <button
          onClick={() => setCount((count) => count + 1)}
          style={css({
            transition: "transform 75ms",
            on: $ => [
              $("&:active", {
                transform: "scale(0.9)"
              })
            ]
          })}
        >
          count is {count}
        </button>
        <p>
          Edit <code>src/app.tsx</code> and save to test HMR
        </p>
      </div>
      <p className="read-the-docs">
        Click on the Vite and Preact logos to learn more
      </p>
    </>
  )
}