Add 404 template

patterns/hidden-404.php

@@ -0,0 +1,42 @@
+<?php
+/**
+ * Title: 404
+ * Slug: twentytwentyfive/hidden-404
+ * Inserter: no
+ *
+ * @package TwentyTwentyFive
+ */
+
+?>
+
+<!-- wp:columns {"style":{"spacing":{"padding":{"top":"50px","bottom":"50px","left":"50px","right":"50px"},"blockGap":{"left":"22px"}}}} -->
+<div class="wp-block-columns" style="padding-top:var(--wp--preset--spacing--50);padding-right:var(--wp--preset--spacing--50);padding-bottom:var(--wp--preset--spacing--50);padding-left:var(--wp--preset--spacing--50)">
+	<!-- wp:column {"width":"40%"} -->
+	<div class="wp-block-column" style="flex-basis:40%">
+		<!-- wp:image {"width":"524px","height":"670px","scale":"cover","sizeSlug":"large","linkDestination":"none"} -->
+		<figure class="wp-block-image size-large is-resized">
+			<img src="<?php echo esc_url( get_template_directory_uri() ); ?>/assets/images/image-from-rawpixel-id-13029755-jpeg.webp" alt="" class="" style="object-fit:cover;width:524px;height:670px" />
+		</figure>
+		<!-- /wp:image -->
+	</div>
+	<!-- /wp:column -->
+
+	<!-- wp:column {"verticalAlignment":"bottom","width":"60%"} -->
+	<div class="wp-block-column is-vertically-aligned-bottom" style="flex-basis:60%">
+		<!-- wp:heading {"level":1,"style":{"typography":{"fontStyle":"normal","fontWeight":"500"}},"fontSize":"x-large"} -->
+		<h1 class="wp-block-heading has-x-large-font-size" style="font-style:normal;font-weight:500">
+			<?php echo esc_html_x( 'Page not found', 'twentytwentyfive' ); ?>
+		</h1>
+		<!-- /wp:heading -->
+
+		<!-- wp:paragraph {"style":{"typography":{"fontSize":"22px"}}} -->
+		<p style="font-size:22px">
+			<?php echo esc_html_x( 'The page you are looking for doesn\'t exist, or it has been moved. Please try searching using the form below.', 'twentytwentyfive' ); ?>
+		</p>
+		<!-- /wp:paragraph -->
+
+		<!-- wp:search {"label":"","placeholder":"<?php echo esc_attr_x( 'Type something...', 'twentytwentyfive' ); ?>","buttonText":"<?php echo esc_attr_x( 'Search', 'twentytwentyfive' ); ?>","style":{"border":{"radius":"50px","width":"1px"},"typography":{"fontSize":"18px"}},"borderColor":"opacity-20"} /-->
+	</div>
+	<!-- /wp:column -->
+</div>
+<!-- /wp:columns -->

readme.txt

@@ -35,3 +35,9 @@ This theme bundles the following third-party resources:
 
 === Images ===
 
+License: CC0 https://creativecommons.org/publicdomain/zero/1.0/
+
+Small totara tree on ridge above Long Point, Porirua Harbour, by Leslie Adkin.
+Public domain.
+image-from-rawpixel-id-13029755-jpeg.webp
+https://www.rawpixel.com/image/13029755

templates/404.html

@@ -0,0 +1,10 @@
+<!-- wp:template-part {"slug":"header","area":"header","tagName":"header"} /-->
+
+<!-- wp:group {"tagName":"main","layout":{"type":"constrained"}} -->
+<main class="wp-block-group">
+    <!-- wp:pattern {"slug":"twentytwentyfive/hidden-404"} /-->
+</main>
+<!-- /wp:group -->
+
+<!-- wp:template-part {"slug":"footer","area":"footer","tagName":"footer"} /-->
+