diff --git a/examples/web/index.css b/examples/web/index.css
index 8ad5b2dc84d823ed784fe47780283c364d71c6cf..78245cd105082b4d47815cc2b680f6cbfd011864 100644
--- a/examples/web/index.css
+++ b/examples/web/index.css
@@ -246,6 +246,15 @@ p {
     top: 24px;
 }
 
+.button-area {
+    user-select: none;
+    -o-user-select: none;
+    -ms-user-select: none;
+    -moz-user-select: none;
+    -khtml-user-select: none;
+    -webkit-user-select: none;
+}
+
 .button-area > * {
     margin-bottom: 12px;
 }