diff --git a/css-teaching/css.css b/css-teaching/css.css
index c472a5f..c577279 100644
--- a/css-teaching/css.css
+++ b/css-teaching/css.css
@@ -166,32 +166,29 @@
 }
 .ov-ce{
 	text-align: center;
+	transform: translate(-50%, -50%);
 }
 .o-visible{
 	width: 170px;
 	height: 85px;
 	border: solid 2px black;
 	overflow: visible;
-	text-align: center;
 }
 .o-hidden{
 	width: 170px;
 	height: 85px;
 	border: solid 2px black;
 	overflow: hidden;
-	text-align: center;
 }
 .o-scroll{
 	width: 175px;
 	height: 95px;
 	border: solid 2px black;
 	overflow: scroll;
-	text-align: center;
 }
 .o-auto{
 	width: 175px;
 	height: 95px;
 	border: solid 2px black;
 	overflow: auto;
-	text-align: center;
 }