:root {
  font-family: Avenir, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  color: white;
  background-color: black;
  font-size: 2em;
}
table {
  border-collapse: collapse;
  margin: 20px auto;
}
td {
  border: 1px solid darkred;
  width: 50px;
  height: 50px;
}
td div, #next div {
  width: 35px;
  height: 35px;
  margin: auto auto;
  border-radius: 50%;
}
header {
  margin-top: 5vh;
  margin-left: 5vh;
  text-align: center;
}
header div {
  margin: 20px;
}
#next div {
  display: inline-block;
}