diff --git a/layouts/404.html b/layouts/404.html
index 0628f45..5e6a065 100644
--- a/layouts/404.html
+++ b/layouts/404.html
@@ -1,27 +1,39 @@
-<div style='font-family:system-ui,"Segoe UI",Roboto,Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji"; height:100vh; text-align:center; display:flex; flex-direction:column; align-items:center; justify-content:center'>
-  <div>
-    <style>
-      body {
-        color: #000;
-        background: #fff;
-        margin: 0;
-      }
-      .next-error-h1 {
-        border-right: 1px solid rgba(0, 0, 0, 0.3);
-      }
-      @media (prefers-color-scheme: dark) {
-        body {
-          color: #fff;
-          background: #000;
-        }
-        .next-error-h1 {
-          border-right: 1px solid rgba(255, 255, 255, 0.3);
-        }
-      }
-    </style>
-    <h1 class="next-error-h1" style='display: inline-block; margin: 0 20px 0 0; padding-right: 23px; font-size: 24px; font-weight: 500; vertical-align: top; line-height: 49px; font-feature-settings: "rlig" 1,"calt" 1,"ss01" 1,"ss06" 1 !important;'>404</h1>
-    <div style="display: inline-block; text-align: left">
-      <h2 style="font-size: 14px; font-weight: 400; line-height: 49px; margin: 0">This page could not be found.</h2>
+<!DOCTYPE html>
+<html lang="en">
+
+<body
+    style='font-family:system-ui,"Segoe UI",Roboto,Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji"; height:100vh; text-align:center; display:flex; flex-direction:column; align-items:center; justify-content:center'>
+    <div>
+        <style>
+            body {
+                color: #000;
+                background: #fff;
+                margin: 0;
+            }
+
+            .next-error-h1 {
+                border-right: 1px solid rgba(0, 0, 0, 0.3);
+            }
+
+            @media (prefers-color-scheme: dark) {
+                body {
+                    color: #fff;
+                    background: #000;
+                }
+
+                .next-error-h1 {
+                    border-right: 1px solid rgba(255, 255, 255, 0.3);
+                }
+            }
+        </style>
+        <h1 class="next-error-h1"
+            style='display: inline-block; margin: 0 20px 0 0; padding-right: 23px; font-size: 24px; font-weight: 500; vertical-align: top; line-height: 49px; font-feature-settings: "rlig" 1,"calt" 1,"ss01" 1,"ss06" 1 !important;'>
+            404</h1>
+        <div style="display: inline-block; text-align: left">
+            <h2 style="font-size: 14px; font-weight: 400; line-height: 49px; margin: 0">This page could not be found.
+            </h2>
+        </div>
     </div>
-  </div>
-</div>
+</body>
+
+</html>
