css improvements

src/frontend/static/style.css

@@ -1,10 +1,12 @@
 body {
+  padding: 5vmin;
   display: grid;
   grid-template-columns: 1fr 1fr;
   grid-template-rows: min-content 1fr;
   grid-template-areas:
     "counters counters"
     "game1 game2";
+  grid-column-gap: 5vmin;
 }
 
 section.counters {
@@ -47,7 +49,7 @@ table.game-board-table {
 
 table.game-board-table tbody.game-board td {
   border: solid 6px black;
-  padding: 3px
+  padding: 3px;
 }
 
 tbody.game-board button,
@@ -70,6 +72,6 @@ tbody.game-board button.square-O {
   background-size: 100% 100%;
 }
 
-tbody.game-board button.square-_ {
+tbody.game-board button.square-_:enabled {
   cursor: pointer;
 }