Codecademy - 25th Exercise (Piano Keys - CSS)

body{
  margin: 0;
  padding: 0;
  font-family: sans-serif;
  background: #ffc63f;
}
.title{
  font-size: 36px;
  margin-top: 10px;
  margin-bottom: 0px;
  padding: 0;
  color: #141c3a;
  text-transform: uppercase;
  letter-spacing: 2px;
  text-align: center;
}
#demo{
  text-align: center;
  font-size: 18px;
  margin-top: 15px;
  color: #141c3a;
  letter-spacing: 1px;
  font-style: italic;
}
.piano{
  width: 305px;
  height: 210px;
  display: block;
  margin: 0 auto;
  background-color: #fd4d3f;
  margin-top: 30px;
}
.key{
  width: 30px;
  height: 200px;
  display: inline-block;
  border: solid #141c3a 2px;
  box-shadow: 2px 5px;
  background-color: white;
  color: #141c3a;
}
.black-key{
  width: 25px;
  height: 100px;
  display: inline-block;
  background-color: #141c3a;
  color: white;
  position: absolute;
  margin-left: -12px;
  padding: 0px;
}
.keynote{
  width: 20px;
  height: 20px;
  text-align: center;
  display: block;
  margin: 0 auto;
  margin-top: 175px;
  color: #141c3a;
}
.black-keynote{
  width: 20px;
  height: 20px;
  text-align: center;
  display: block;
  margin: 0 auto;
  margin-top: 75px;
}
#lyrics{
  width: 400px;
  height: 240px;
  display: block;
  margin: 0 auto;
  padding-left: 20px;
  margin-top: 50px;
  background-color: #fd4d3f;
}
#column-one, #column-two, #column-three, #column-four, #column-five, #column-six, #column-optional{
  width: 90px;
  display: inline-block;
  text-align: center;
  margin-top: 30px;
}
#column-optional{
  display: none;
}
#word-one, #word-two, #word-three, #word-four, #word-five, #word-six, #word-optional{
  background-color: white;
  width: 90px;
  height: 25px;
  padding-top: 10px;
  letter-spacing: 5px;
  color: #141c3a;
}
#letter-note-one, #letter-note-two, #letter-note-three, #letter-note-four, #letter-note-five, #letter-note-six, #letter-note-optional{
  color: white;
  width: 25px;
  height: 25px;
  margin-top: 15px;
  margin-left: 35px;
}
#first-next-line, #second-next-line, #third-next-line, #fourth-next-line{
  width: 80px;
  height: 40px;
  font-size: 16px;
  position: absolute;
  margin-top: 30px;
  margin-left: 10px;
  border: none;
  background-color: #ffc63f;
  color: #141c3a;
  letter-spacing: 1px;
  cursor: pointer;
}