diff --git a/themes/tiddlywiki/vanilla/base.tid b/themes/tiddlywiki/vanilla/base.tid
index e7a77a295..446a56caa 100644
--- a/themes/tiddlywiki/vanilla/base.tid
+++ b/themes/tiddlywiki/vanilla/base.tid
@@ -1,6 +1,9 @@
 title: $:/themes/tiddlywiki/vanilla/base
 tags: [[$:/tags/stylesheet]]
 
+\define if-no-sidebar(text)
+<$reveal state="$:/state/sidebar" type="nomatch" text="yes" default="yes">$text$</$reveal>
+\end
 \rules only filteredtranscludeinline transcludeinline macrodef macrocallinline
 /*
 ** Start with the normalize CSS reset, and then belay some of its effects
@@ -463,6 +466,17 @@ a.tw-tiddlylink-external:hover {
 		width: {{$:/themes/tiddlywiki/vanilla/metrics##storywidth}};
 		padding: 42px 42px 42px 42px;
 	}
+
+
+
+<<if-no-sidebar "
+
+	.story-river {
+		width: auto;
+	}
+
+">>
+
 }
 
 @media print {
@@ -526,6 +540,14 @@ a.tw-tiddlylink-external:hover {
 		width: {{$:/themes/tiddlywiki/vanilla/metrics##tiddlerwidth}};
 	}
 
+<<if-no-sidebar "
+
+	.tw-tiddler-frame {
+		width: auto;
+	}
+
+">>
+
 	.tw-tiddler-info {
 		margin: 0 -42px 0 -42px;
 	}