Morden: Add subtle box-shadow to the page

morden/sass/_extra-child-theme.scss

@@ -71,6 +71,7 @@ a {
 
 #page {
 	background: #{map-deep-get($config-global, "color", "background", "default")};
+	box-shadow: 0 0 30px rgba(#000, 0.2);
 	margin-left: auto;
 	margin-right: auto;
 

morden/style-rtl.css

@@ -3380,6 +3380,7 @@ p:not(.site-title) a:hover {
 
 #page {
 	background: white;
+	box-shadow: 0 0 30px rgba(0, 0, 0, 0.2);
 	margin-right: auto;
 	margin-left: auto;
 }

morden/style.css

@@ -3385,6 +3385,7 @@ p:not(.site-title) a:hover {
 
 #page {
 	background: white;
+	box-shadow: 0 0 30px rgba(0, 0, 0, 0.2);
 	margin-left: auto;
 	margin-right: auto;
 }