feat: add landing page for mobile viewport

apps/gacha/src/app/layout.tsx

@@ -4,7 +4,7 @@ import { Navbar } from '@imphnen-frontend-service/ui/organisms';
 
 export const AppLayout: FC = (): ReactElement => {
   return (
-    <main className="bg-primary-50 min-h-screen px-20 py-[60px]">
+    <main className="bg-primary-50 min-h-screen px-8 py-[60px]">
       <Navbar />
       <Outlet />
     </main>

apps/gacha/src/app/page.tsx

@@ -1,7 +1,13 @@
+import { LandingPage } from '@imphnen-frontend-service/ui/organisms';
 import { FC, ReactElement } from 'react';
 
 export const Components: FC = (): ReactElement => {
-  return <>Hallo</>;
+  return (
+    <>
+      <LandingPage />
+      <div></div>
+    </>
+  );
 };
 
 export default Components;