Move to TanStack Start from Next.js (#184)

web/app/hooks/use-theme.ts

@@ -0,0 +1,25 @@
+import * as React from "react"
+
+export const useTheme = () => {
+  const [isDarkMode, setIsDarkMode] = React.useState(false)
+
+  React.useEffect(() => {
+    const darkModeMediaQuery = window.matchMedia("(prefers-color-scheme: dark)")
+    setIsDarkMode(darkModeMediaQuery.matches)
+
+    const handleChange = (e: MediaQueryListEvent) => {
+      const newDarkMode = e.matches
+      setIsDarkMode(newDarkMode)
+    }
+
+    darkModeMediaQuery.addEventListener("change", handleChange)
+
+    return () => {
+      darkModeMediaQuery.removeEventListener("change", handleChange)
+    }
+  }, [])
+
+  return isDarkMode
+}
+
+export default useTheme