diff --git a/kallithea/public/css/style.css b/kallithea/public/css/style.css
--- a/kallithea/public/css/style.css
+++ b/kallithea/public/css/style.css
@@ -4787,6 +4787,10 @@ span.pr-closed-tag {
     line-height: 1.5em;
 }
 
+.pr-box {
+    max-width: 978px;
+}
+
 /****
   PERMS
 *****/
diff --git a/kallithea/templates/pullrequests/pullrequest_show.html b/kallithea/templates/pullrequests/pullrequest_show.html
--- a/kallithea/templates/pullrequests/pullrequest_show.html
+++ b/kallithea/templates/pullrequests/pullrequest_show.html
@@ -23,7 +23,7 @@ ${self.repo_context_bar('showpullrequest
         ${self.breadcrumbs()}
     </div>
 
-    <div class="form" style="float: left">
+    <div class="form pr-box" style="float: left">
         <div class="pr-details-title ${'closed' if c.pull_request.is_closed() else ''}">
             ${_('Title')}: ${c.pull_request.title}
             %if c.pull_request.is_closed():