Add 404 page

i18n.json

@@ -9,6 +9,7 @@
       "/house": ["house", "common"],
       "/tos": ["tos", "common"],
       "/hcunews": ["hcunews", "common"],
-      "/minecraft": ["minecraft", "common"]
+      "/minecraft": ["minecraft", "common"],
+      "/404": ["404", "common"]
     }
   }

locales/en/404.json

@@ -0,0 +1,4 @@
+{
+    "caption": "The requested page does not exist on this website.",
+    "return": "Return to top"
+}

locales/ja/404.json

@@ -0,0 +1,4 @@
+{
+    "caption": "要求されたページはこのウェブサイト上に存在しません。",
+    "return": "トップページへ戻る"
+}

pages/404.js

@@ -0,0 +1,29 @@
+// Base layout
+import Layout from "./components/Layout"
+
+// React Router
+import { useRouter } from 'next/router'
+
+// Next.js
+import Link from 'next/link'
+import useTranslation from 'next-translate/useTranslation'
+
+export default function Custom404(props) {
+  const router = useRouter()
+  const { locale, locales, defaultLocale, pathname } = router
+  const { t, lang } = useTranslation("404")
+
+  return (
+    <Layout title="404">
+      <div className="text-center mb-10 mt-10">
+      <p className="text-3xl">404</p>
+      <p className="text-xl">{t('caption')}</p>
+      <Link href="/">
+        <a>
+            <p className="mt-5">{t('return')}</p>
+        </a>
+      </Link>
+      </div>
+    </Layout>
+  )
+}