feat: put link to skills in separate nav

src/pages/index.astro

@@ -25,11 +25,15 @@ import BaseLayout from "../layouts/BaseLayout.astro";
       <section class="text-soft">
         <p>Fachinformatiker für Anwendungsentwicklung</p>
       </section>
-      <nav>
-        <ul class="flex flex-col gap-2">
-          <li>
-            <a href="/skills">Skills</a>
+      <nav aria-label="Seitennavigation">
+        <ul class="flex gap-2">
+          <li class="flex justify-center">
+            <a href="/skills" class="underline font-medium">Skills</a>
           </li>
+        </ul>
+      </nav>
+      <nav aria-label="Externe Links">
+        <ul class="flex flex-col gap-2">
           <li>
             <ButtonLink
               class="link-matrix"

src/pages/skills.astro

@@ -33,8 +33,8 @@ const kcStart = new Date(2026, 0, 1);
   <main class="flex items-center justify-center">
     <article>
       <div class="mb-8 flex items-baseline gap-6">
-        <a href="/" title="Zurück" class="text-soft rounded-full"
-          ><ArrowLeftCircle class="size-9" /></a
+        <a href="/" aria-label="Zurück" title="Zurück" class="text-soft rounded-full"
+          ><ArrowLeftCircle role="presentation" class="size-9" /></a
         >
         <h1>Skills</h1>
       </div>