*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  background-image: linear-gradient(90deg, rgb(199, 15, 101), #7157, lightpink);
  margin: 0;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.piano {
  display: flex;
}

.key {
  height: calc(var(--width) * 4);
  width: var(--width);
  box-shadow: inset 0px 10px 5px black;
}

.White {
  --width: 90px;
  height: 350px;
  background-color: white;
  border: 1px solid #333;
}

.Black {
  --width: 60px;
  height: 240px;
  background-color: black;
  margin-left: calc(var(--width) / -2);
  margin-right: calc(var(--width) / -2);
  z-index: 1;
  border: 1px solid #333;
}

.White.active{
    background-color: #ccc;
}

.Black.active{
    background-color: #333;
}