in beta/src/pages/_document.tsx [18:54]
(function () {
function setTheme(newTheme) {
window.__theme = newTheme;
if (newTheme === 'dark') {
document.documentElement.classList.add('dark');
} else if (newTheme === 'light') {
document.documentElement.classList.remove('dark');
}
}
var preferredTheme;
try {
preferredTheme = localStorage.getItem('theme');
} catch (err) { }
window.__setPreferredTheme = function(newTheme) {
preferredTheme = newTheme;
setTheme(newTheme);
try {
localStorage.setItem('theme', newTheme);
} catch (err) { }
};
var initialTheme = preferredTheme;
var darkQuery = window.matchMedia('(prefers-color-scheme: dark)');
if (!initialTheme) {
initialTheme = darkQuery.matches ? 'dark' : 'light';
}
setTheme(initialTheme);
darkQuery.addListener(function (e) {
if (!preferredTheme) {
setTheme(e.matches ? 'dark' : 'light');
}
});
})();