diff --git a/core/styles/tiddlywiki.css b/core/styles/tiddlywiki.css
index a346410bf..1e29bd3fa 100644
--- a/core/styles/tiddlywiki.css
+++ b/core/styles/tiddlywiki.css
@@ -5008,6 +5008,35 @@ body {
   padding-top: 40px;
 }
 
+/*
+Tweaks for full screen mode
+*/
+
+html:-webkit-full-screen {
+  width: 100%;
+  height: 100%;
+}
+
+html:-moz-full-screen {
+  width: 100%;
+  height: 100%;
+}
+
+html:-ms-full-screen {
+  width: 100%;
+  height: 100%;
+}
+
+html:-o-full-screen {
+  width: 100%;
+  height: 100%;
+}
+
+html:full-screen {
+  width: 100%;
+  height: 100%;
+}
+
 /*
 Tiddler styles
 */
diff --git a/cssbuild/tiddlywiki.less b/cssbuild/tiddlywiki.less
index 3a78d747a..31885f295 100644
--- a/cssbuild/tiddlywiki.less
+++ b/cssbuild/tiddlywiki.less
@@ -42,6 +42,15 @@ body {
 	padding-top: @navbarHeight;	// Allow for the navbar
 }
 
+/*
+Tweaks for full screen mode
+*/
+html:-webkit-full-screen	{ width: 100%; height: 100%; }
+html:-moz-full-screen		{ width: 100%; height: 100%; }
+html:-ms-full-screen		{ width: 100%; height: 100%; }
+html:-o-full-screen			{ width: 100%; height: 100%; }
+html:full-screen			{ width: 100%; height: 100%; }
+
 /*
 Tiddler styles
 */