<script> import Timer from './Timer.svelte'; let open = false; let seconds = 0; const toggle = () => (open = !open); const handleTick = () => (seconds += 1); </script> <div> <button on:click={toggle}>{open ? 'Close' : 'Open'} Timer</button> <p> The Timer component has been open for {seconds} {seconds === 1 ? 'second' : 'seconds'} </p> {#if open} <Timer callback={handleTick} /> {/if} </div>