diff --git a/src/lib/TestCard.svelte b/src/lib/TestCard.svelte
index e16b42e..de93e06 100644
--- a/src/lib/TestCard.svelte
+++ b/src/lib/TestCard.svelte
@@ -4,6 +4,7 @@
 	import Axes from '$lib/Axes.svelte';
 	import ColorGradient from '$lib/ColorGradient.svelte';
 	import BrightnessGradient from '$lib/BrightnessGradient.svelte';
+	import { onMount } from 'svelte';
 
 	let sizes = {
 		blockSize: 64,
@@ -19,6 +20,12 @@
 	$: circleBlocks =
 		2 * Math.floor((Math.min(sizes.horizontalCount, sizes.verticalCount) * 0.66) / 2) +
 		(sizes.horizontalCount % 2);
+
+	onMount(() => {
+		window.addEventListener('dblclick', () => {
+			document.body.requestFullscreen();
+		})
+	});
 </script>
 
 <div