botsArena/src/arenas/connectFour/style.css

.tabledoc{border-collapse:collapse;}
.tabledoc tr td,.tabledoc tr th{border: 1px solid green; padding-left: 5px;}

.battleGrid{display:table-cell; padding-left:10px; border-collapse:collapse; margin: 20px 20px 20px 20px;}
.battleGrid tr{}
.battleGrid tr td{border: 1px dashed green; text-align: center; font-weight: bold;min-width:20px; height:20px;}