snapshot of https://github.com/shadcn-ui/ui.git (main, 2026-09-15; blobs > 131072B omitted)

apps/v4/hooks/use-mobile.ts

@@ -0,0 +1,17 @@
+import * as React from "react"
+
+export function useIsMobile(mobileBreakpoint = 768) {
+  const [isMobile, setIsMobile] = React.useState<boolean | undefined>(undefined)
+
+  React.useEffect(() => {
+    const mql = window.matchMedia(`(max-width: ${mobileBreakpoint - 1}px)`)
+    const onChange = () => {
+      setIsMobile(window.innerWidth < mobileBreakpoint)
+    }
+    mql.addEventListener("change", onChange)
+    setIsMobile(window.innerWidth < mobileBreakpoint)
+    return () => mql.removeEventListener("change", onChange)
+  }, [mobileBreakpoint])
+
+  return !!isMobile
+}