* {
  margin: 0;
  text-align: center;
}

h1 {
  margin-bottom: 10px;
}

body {
  display: grid;
  justify-content: center;
  align-content: center;
  margin-top: 20px;
}

#container {
  display: inline-grid;
  border: 2px solid black;
  background-color: white;
  width: 500px;
  height: 500px;
  /* grid-template-columns: repeat(16, 1fr);
  grid-template-rows: repeat(16, 1fr); */
}

.grid {
  border: 1px solid #ddd;
}

button {
  border-radius: 5px;
  background-color: #eee;
  border-color: black;
  margin: 5px;
}