diff --git a/static/feed_style.xsl b/static/feed_style.xsl
index 1a2a509..1e413bb 100644
--- a/static/feed_style.xsl
+++ b/static/feed_style.xsl
@@ -14,13 +14,8 @@
         <meta charset="utf-8"/>
         <meta http-equiv="content-type" content="text/html; charset=utf-8"/>
         <meta name="viewport" content="width=device-width, initial-scale=1"/>
-        <!-- The base URL is assumed to be the first URL in the sitemap. -->
-        <xsl:variable name="baseUrl" select="(sitemap:urlset/sitemap:url)[1]/sitemap:loc"/>
-        <!-- Remove http[s]:// -->
-        <xsl:variable name="baseUrlWithoutProtocol" select="substring-after($baseUrl, '://')"/>
-        <!-- Remove trailing slash -->
-        <xsl:variable name="clean_base_url" select="substring-before($baseUrlWithoutProtocol, '/')"/>
-        <link rel="stylesheet" href="{$baseUrl}main.css"/>
+        <xsl:variable name="baseUrl" select="/atom:feed/tabi:metadata/tabi:base_url"/>
+        <link rel="stylesheet" href="{$baseUrl}/main.css"/>
         <link rel="stylesheet" href="{/atom:feed/atom:link[@rel='extra-stylesheet']/@href}" />
 
       </head>
diff --git a/templates/atom.xml b/templates/atom.xml
index 0f50753..0546214 100644
--- a/templates/atom.xml
+++ b/templates/atom.xml
@@ -9,6 +9,7 @@
 <?xml-stylesheet href="{{ get_url(path='/feed_style.xsl', trailing_slash=false) | safe }}" type="text/xsl"?>
 <feed xmlns="http://www.w3.org/2005/Atom" xml:lang="{{ lang }}">
     <tabi:metadata xmlns:tabi="https://github.com/welpo/tabi">
+        <tabi:base_url>{{ config.base_url }}</tabi:base_url>
         <tabi:separator>
             {{  config.extra.separator | default(value="•") }}
         </tabi:separator>