.alignment{
  text-align: center;
  margin-bottom: 30px;
}

.jumbotron{
  min-width: 450px;
  padding-top: 1em;
  padding-bottom: 2em;
}

table{
  margin: auto;
  margin-top: 20px;
}

td{
  font-size: 5em;
  text-align: center;
  width: 135px;
  height: 135px;
  max-width: 150px;
  min-width: 60px;
  border: 5px solid black;
}