PT Sans is replaced with Helvetica for reading mode

styles/screen.css

@@ -115,6 +115,7 @@ A {
 	margin:-8px 0 0 -45px;
 	color:#BBB;
 	line-height:1;
+	font-family:'PT Sans', sans-serif;
 	font-size:100px;
 	content:'\201C';
 	}