feat(carousel): 2 cols tablet, 3 cols desktop; equal-height cards

- PostOverviewBlock carousel: md:2 cols, lg:3 cols via snap-scroll
- PostCard: add class prop for external styling
- Carousel cards: h-full for equal height

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/components/PostCard.svelte

@@ -22,12 +22,14 @@
     href,
     tagBase = "/posts/tag",
     commentCount = null,
+    class: className = "",
   }: {
     post: PostWithImage;
     href: string;
     tagBase?: string;
     /** Approved comment count. `null` = unknown/loading, hide badge. `0` = also hide. */
     commentCount?: number | null;
+    class?: string;
   } = $props();
 
   const rawImg = $derived(post._rawImageUrl);
@@ -52,7 +54,7 @@
 <Card
   {href}
   layout="post"
-  class={isPastEvent ? "opacity-70 grayscale" : ""}
+  class="{isPastEvent ? 'opacity-70 grayscale' : ''} {className}"
 >
   <div class="relative aspect-3/2 w-full overflow-hidden bg-stein-100">
     {#if rawImg}

src/lib/components/blocks/PostOverviewBlock.svelte

@@ -1,7 +1,8 @@
 <script lang="ts">
   import { marked } from "$lib/markdown-safe";
   import PostCard from "../PostCard.svelte";
-  import Carousel from "$lib/components/Carousel.svelte";
+  import Icon from "@iconify/svelte";
+  import "$lib/iconify-offline";
   import { getBlockLayoutClasses } from "$lib/block-layout";
   import type { PostOverviewBlockData } from "$lib/block-types";
   import type { PostEntry } from "$lib/cms";
@@ -21,6 +22,13 @@
   const posts = $derived((block.postsResolved ?? []) as (PostEntry & { _resolvedImageUrl?: string })[]);
   const design = $derived(block.design || "cards");
   const tagBase = "/posts/tag";
+
+  let scroller: HTMLDivElement | undefined = $state();
+  function scrollByPage(dir: 1 | -1) {
+    if (!scroller) return;
+    scroller.scrollBy({ left: scroller.clientWidth * dir * 0.9, behavior: "smooth" });
+  }
+
   // Hide the entire block (headline, intro, footer link) when there are no
   // posts and no intro text — otherwise an empty section with just a heading
   // sits on the page.
@@ -74,16 +82,42 @@
       {/each}
     </div>
   {:else if design === "carousel" && posts.length > 0}
-    <Carousel count={posts.length} ariaLabel={block.headline ?? "Beiträge"}>
-      {#snippet item(i)}
-        <PostCard
-          post={posts[i]}
-          href={postHref(posts[i])}
-          tagBase={tagBase}
-          commentCount={commentCounts[postSlugForComments(posts[i])] ?? null}
-        />
-      {/snippet}
-    </Carousel>
+    <div class="relative">
+      <div
+        bind:this={scroller}
+        class="flex gap-4 overflow-x-auto scroll-smooth snap-x snap-mandatory pb-2 [scrollbar-width:thin]"
+      >
+        {#each posts as post}
+          <div class="shrink-0 snap-start flex flex-col w-full md:w-[calc((100%-1rem)/2)] lg:w-[calc((100%-2rem)/3)]">
+            <PostCard
+              post={post}
+              href={postHref(post)}
+              tagBase={tagBase}
+              commentCount={commentCounts[postSlugForComments(post)] ?? null}
+              class="h-full"
+            />
+          </div>
+        {/each}
+      </div>
+      {#if posts.length > 1}
+        <button
+          type="button"
+          onclick={() => scrollByPage(-1)}
+          aria-label="Zurück"
+          class="hidden md:flex absolute -left-3 top-1/2 -translate-y-1/2 -translate-x-1/2 size-7 items-center justify-center rounded-full bg-white/90 border border-stein-200 shadow-sm hover:bg-white hover:border-wald-700 transition"
+        >
+          <Icon icon="mdi:chevron-left" class="size-4" aria-hidden="true" />
+        </button>
+        <button
+          type="button"
+          onclick={() => scrollByPage(1)}
+          aria-label="Weiter"
+          class="hidden md:flex absolute -right-3 top-1/2 -translate-y-1/2 translate-x-1/2 size-7 items-center justify-center rounded-full bg-white/90 border border-stein-200 shadow-sm hover:bg-white hover:border-wald-700 transition"
+        >
+          <Icon icon="mdi:chevron-right" class="size-4" aria-hidden="true" />
+        </button>
+      {/if}
+    </div>
   {/if}
 
   {#if posts.length > 0}