Hide RichText heading underline on PDPs; more breathing room after Hero

- der-eine's original "Was kann er?" heading was plain text, no
  decoration — RichText.tsx's shared heading converter always appends a
  small brand-underline span (wanted on blog/legal pages, not here).
  Hidden via a scoped CSS selector, same approach as the earlier icon-
  color overrides, not touching the shared component.
- Generic block spacing bumped from py-8 sm:py-12 to py-12 md:py-16,
  matching der-eine's own original Focus.tsx rhythm — felt too tight
  right after the Hero (reported 2026-08-30).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013Eg6h91yngXmSnM51wxXM8

app/components/ProductBlocks.tsx

@@ -99,7 +99,10 @@ export async function ProductBlocks({ product }: { product: Product }) {
         return <div key={block.id}>{renderProductBlock(block, ctx)}</div>;
       }
       return (
-        <Reveal key={block.id} className="w-full px-[var(--layout-padding-x)] py-8 sm:py-12">
+        // py-12 md:py-16 — matches der-eine's own original Focus.tsx
+        // rhythm exactly (this system's reference template); py-8 sm:py-12
+        // read as too tight right after the hero (reported 2026-08-30).
+        <Reveal key={block.id} className="w-full px-[var(--layout-padding-x)] py-12 md:py-16">
           {renderProductBlock(block, ctx)}
         </Reveal>
       );
@@ -145,9 +148,16 @@ export function renderProductBlock(block: ProductBlock, ctx: ProductBlockContext
     // below — without this, a heading/prose block sat edge-to-edge while
     // the cards under it were capped, reading as "still not width-limited"
     // even after the cards themselves were (reported 2026-08-30).
+    // [&_h2>span]:hidden — RichText's heading converter always appends a
+    // small brand-underline span under every h2 (shared with blog/legal
+    // pages, where it's wanted); der-eine's own original heading had no
+    // such decoration, plain text only (reported 2026-08-30). Hidden via
+    // CSS rather than a RichText prop, same "override scoped to
+    // ProductBlocks.tsx, don't touch the shared renderer" approach as the
+    // quote/stepRow cases.
     case "richTextSection":
       return (
-        <div key={block.id} className="max-w-[48rem] mx-auto">
+        <div key={block.id} className="max-w-[48rem] mx-auto [&_h2>span]:hidden">
           <RichText content={block.content} />
         </div>
       );