a タグ周りの構造を修正

Author: mucho613

_includes/header.html

@@ -13,9 +13,9 @@ <h1 class="xl:block hidden mx-auto max-w-lg pt-5 px-8">
           alt="DojoCon Japan 2025 Inspire Next." />
       </a>
       <div class="flex items-cetner gap-x-2 shrink-0">
-        <div class="px-3 py-2 rounded-sm text-center bg-[#cc8f2e] text-[#f5f5f5] justify-center">
-          <a href="/registration/">参加申込</a>
-        </div>
+        <a href="/registration/" class="px-3 py-2 rounded-sm text-center bg-[#cc8f2e] text-[#f5f5f5] justify-center">
+          参加申込
+        </a>
         <button id="menu-btn" type="button" aria-label="メニューを開く"
           class="flex p-2 size-10 shrink-0 flex-col items-center justify-center rounded border border-gray-300 bg-white cursor-pointer">
           <i class="fa-solid fa-bars"></i>