docs: improve placement of open button when iframed

Author: jpoehnelt

.storybook/page.css

@@ -2,3 +2,11 @@
 .docblock-argstable-body td:nth-child(3) {
     display: none;
 }
+
+body {
+    height: 100vh;
+}
+
+#storybook-root {
+    height: 100%;
+}

src/stories/utils/lazy-preview-element.ts

@@ -23,8 +23,10 @@ export class LazyPreviewElement<
 		const style = document.createElement("style");
 		style.textContent = `
 lazy-preview {
+    height: 100%;
 	display: flex;
 	justify-content: center;
+	align-items: center;
 }
 
 lazy-preview button {