body {
  font-family: Arial, sans-serif;
  text-align: center;
}

#array {
  display: flex;
  justify-content: center;
  margin: 30px;
}

.block {
  width: 40px;
  height: 40px;
  margin: 5px;
  line-height: 40px;
  border: 1px solid black;
  background-color: #f2f2f2;
}

.active {
  background-color: yellow;
}

.sorted {
  background-color: lightgreen;
}

input, button {
  padding: 6px;
  margin: 5px;
}