Set fixed column count

sass/chordpro.scss

@@ -26,9 +26,8 @@ table {
 }
 
 html.column-view .song {
-	column-width: 15em;
-  column-gap: 6em;
-	column-fill: auto;
+	column-width: auto;
+	column-count: 2;
 	max-height: 100vh;
 	overflow: visible;
 

sass/style.scss

@@ -179,6 +179,8 @@ main.song {
 	height: 100dvh;
 	display: flex;
 	flex-direction: column;
+	max-width: 60em;
+	margin: 0 auto;
 
 	iframe {
 		flex-grow: 1;