Files
fuz-site/src/islands/ThemeToggle.jsx

43 lines
1.1 KiB
JavaScript

import { useEffect, useState } from "preact/hooks";
export default function ThemeToggle() {
const [isDark, setIsDark] = useState(false);
const [mounted, setMounted] = useState(false);
useEffect(() => {
// unikamy SSR, działamy dopiero po stronie klienta
if (typeof window === "undefined") return;
const saved = localStorage.getItem("theme");
const systemPrefersDark = window.matchMedia("(prefers-color-scheme: dark)").matches;
const dark = saved === "dark" || (!saved && systemPrefersDark);
setIsDark(dark);
document.documentElement.classList.toggle("dark", dark);
setMounted(true);
}, []);
const toggleTheme = () => {
const newDark = !isDark;
setIsDark(newDark);
document.documentElement.classList.toggle("dark", newDark);
localStorage.setItem("theme", newDark ? "dark" : "light");
};
if (!mounted) return null;
return (
<button
type="button"
onClick={toggleTheme}
class="theme-toggle-btn"
aria-label="Zmień motyw"
>
{isDark ? "🌙" : "🌞"}
</button>
);
}