Determine if focus is within a specific element.
Focus is within form: false
<script lang="ts"> import { IsFocusWithin } from "runed"; let formElement = $state<HTMLFormElement>(); const focusWithinForm = new IsFocusWithin(() => formElement); </script> <p>Focus within form: {focusWithinForm.current}</p> <form bind:this={formElement}> <input type="text" /> <button type="submit">Submit</button> </form>