diff --git a/css/styles.css b/css/styles.css
index 4054acc..562389b 100644
--- a/css/styles.css
+++ b/css/styles.css
@@ -8,8 +8,9 @@ body, html {
   margin: 0;
   /* Disable text selection */
   -webkit-user-select: none; /* Safari */
-  -ms-user-select: none; /* IE 10 and IE 11 */
-  user-select: none; /* Standard syntax */
+  -moz-user-select: none;    /* Firefox */
+  -ms-user-select: none;     /* Internet Explorer/Edge */
+  user-select: none;         /* Non-prefixed version, currently supported by Chrome, Opera and Safari */
 }
 
 body {