#scenario{border-collapse:collapse;position:relative}.sc-tile{width:50px;height:50px;border:1px solid green}.defender{width:30px;height:30px;background-color:green}.bullet{width:10px;height:10px;position:absolute;background-color:red;border-radius:10px;border:1px solid #000}.attacker{width:30px;height:30px;background-color:blue}