Does it provide a variable to say whether it's on mobile(phone) or PC ？

[Chasen-Zhang]

Does it provide a variable to say whether it's on mobile(phone) or PC ？

[Josh-Cena]

There's a @theme/hooks/useWindowSize hook which you can use in your React app. useWindowSize() returns desktop, mobile, or ssr if it is server-side rendered. We use it ourselves:

docusaurus/packages/docusaurus-theme-classic/src/theme/DocSidebar/index.tsx

Lines 123 to 136 in 44b87c7

	const windowSize = useWindowSize();
	// Desktop sidebar visible on hydration: need SSR rendering
	const shouldRenderSidebarDesktop =
	windowSize === 'desktop' || windowSize === 'ssr';
	// Mobile sidebar not visible on hydration: can avoid SSR rendering
	const shouldRenderSidebarMobile = windowSize === 'mobile';
	return (
	<>
	{shouldRenderSidebarDesktop && <DocSidebarDesktopMemo {...props} />}
	{shouldRenderSidebarMobile && <DocSidebarMobileMemo {...props} />}
	</>