h1 {
  text-align: center;
}

.header {
  margin-bottom: 32px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.grid {
  width: 600px;
  height: 600px;
  margin: 0 auto;
}

.row {
  display: flex;
}

.box {
  width: 200px;
  height: 200px;
  border: 1px solid #222222;
  box-sizing: border-box;
  text-align: center;
  line-height: 200px;
  font-size: 64px;
  cursor: pointer;
}