Fixed example

src/routes/readme/7/+page.svelte

@@ -19,7 +19,7 @@
 			</div>
 
 			<div class="card--actions">
-				<a class="btn" href="#whatever">Call to action</a>
+				<a class="btn" href="/readme">Call to action</a>
 			</div>
 		</div>
 	`;

src/routes/readme/7/Button.svelte

@@ -1,12 +1,15 @@
 <script lang="ts">
+	import { base } from '$app/paths';
 	import type { HTMLButtonAttributes } from 'svelte/elements';
 
 	export let href: string | undefined = undefined;
 	export let type: HTMLButtonAttributes['type'] = 'button';
 </script>
 
 {#if href}
-	<a {...$$restProps} {href}><slot /></a>
+	<a {...$$restProps} href={href?.startsWith('/') ? base + href : href}
+		><slot /></a
+	>
 {:else}
 	<button {...$$restProps} {type}><slot /></button>
 {/if}