diff --git a/css/chess.css b/css/chess.css
index 0785f4e..0c1e87e 100644
--- a/css/chess.css
+++ b/css/chess.css
@@ -467,7 +467,7 @@ button:disabled .silhouette {
    background-image: url(../svg/new-game.svg);
    background-size: contain;
    background-repeat: no-repeat;
-   opacity: 25%;
+   opacity: 0.25;
 }
 
 .game-tile-title {