Index: wp-includes/sitemaps/class-wp-sitemaps-stylesheet.php
===================================================================
--- wp-includes/sitemaps/class-wp-sitemaps-stylesheet.php	(revision 48180)
+++ wp-includes/sitemaps/class-wp-sitemaps-stylesheet.php	(working copy)
@@ -89,6 +89,8 @@
 				<style>{$css}</style>
 			</head>
 			<body>
+				<div id="sitemap">
+
 				<div id="sitemap__header">
 					<h1>{$title}</h1>
 					<p>{$description}</p>
@@ -129,6 +131,8 @@
 						</tbody>
 					</table>
 				</div>
+
+				</div>
 			</body>
 		</html>
 	</xsl:template>
@@ -195,6 +199,8 @@
 				<style>{$css}</style>
 			</head>
 			<body>
+				<div id="sitemap">
+
 				<div id="sitemap__header">
 					<h1>{$title}</h1>
 					<p>{$description}</p>
@@ -223,6 +229,8 @@
 						</tbody>
 					</table>
 				</div>
+
+				</div>
 			</body>
 		</html>
 	</xsl:template>
