fix css for mobile devices

Signed-off-by: Artem Anufrij <artem.anufrij@live.de>

css/style.css

@@ -856,18 +856,19 @@ button.button-inline:hover {
 	.board-header-controls.app-popover-menu-utils {
 		display: none;
 	}
-
-	.stack {
-		width: 100%;
-		display: block;
-	}
-
 	.stack h2 .stack-actions {
 		display: flex;
 		opacity: 0.25;
 	}
 }
 
+@media (max-width: 480px) {
+	.stack {
+		width: 100%;
+		display: block;
+	}
+}
+
 /**
  * Markdown rendering
  */