styles.css

body {
  font-family: monospace;
  color: #2b1061;
}

body::after {
  content: '';
  background-image: url(./supermario.jpg);
  background-size: cover;
  opacity: 1;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  position: fixed;
  z-index: -1;
}

h1 {
  font-size: 3em;
}

.row > div {
  background-color: rgba(189, 172, 247, 0.3);
  float: left;
  width: 100px;
  height: 100px;
  cursor: pointer;
  font-size: 3rem;
  line-height: 7rem;
}

.row {
  /* background-color: white; */
  clear: both;
  margin: auto;
  width: 302px;
}

.top {
  border-bottom: 1px solid #1e0b5a;
}

.bottom {
  border-top: 1px solid #1e0b5a;
}

.left {
  border-right: 1px solid #1e0b5a;
}

.right {
  border-left: 1px solid #1e0b5a;
}

.highlight:hover {
  background-color: rgba(189, 172, 247, 0.6);;
}

#board {
  padding-top: 8rem;
  text-align: center;
}