styles.css

body {
  background-image: url("img/redwall.jpg");
  background-color: #000;
  text-align: center;
 }

 h1 {
  color: #ffc600;
  font-size: 50px;
  text-shadow: 5px 5px 5px black;
  font-size: 3.75em;
  text-transform: uppercase;
  letter-spacing: 4px;
  padding-top: 40px;
  margin-bottom: 0;
 }

 p {
   color: white;
   font-size: 1.2em;
   font-style: italic;
   margin: 10px 0;
   text-shadow: 0 0 5px black;
 }

 .keys {
   display: flex;
   flex-wrap: wrap;
   flex-direction: row;
 }

.key {
  border: 4px solid black;
  border-radius: 5px;
  margin: 1rem;
  font-size: 1.5rem;
  padding: 1rem .5rem;
  transition: all 0.1s;
  flex: 1 1 115px;
  text-align: center;
  color: white;
  background: rgba(0, 0, 0, 0.4);
  text-shadow: 0 0 5px black;
}

.playing {
  transform: scale(1.1);
  border-color: #ffc600;
  box-shadow: #ffc600;
}

kbd {
  display: block;
  font-size: 40px;
}

.sound {
  font-size: 0.75em;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: #ffc600;
}