style.css

body {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  height: 100vh;
  background-color: #f0f0f0;
}

.container {
  display: grid;
  grid-template-columns: repeat(var(--grid-size), 1fr);
  grid-template-rows: repeat(var(--grid-size), 1fr);
  width: 60vmin;
  height: 60vmin;
  gap: 1px;
}

/* Targeting each div inside the container. */
.container {
  border: 1px solid #666666;
}

/* using "::after" pseudoelement to change the divs to a square block. This could also be achieved with different means.  */
.container > div::after {
  content: "";
  display: block;
  padding-top: 100%; /* Makes the div a square by setting height relative to width */
}

.button {
  position: absolute;
  top: 20px;
  right: 20px;
  padding: 15px;
}

.info {
  position: absolute;
  top: 20px;
  left: 20px;
}