#piano {
  margin-top: 15px;
  display: block;
  white-space: nowrap;
  height: 25vh;
  max-height: 200px;
  min-height: 100px;
  background: #aaa;
  background: #aaa;
  overflow-y: hidden;
  overflow-x: scroll;
}

#piano > div {
  position: relative;
  box-sizing: border-box;
  height: 100%;
  width: 40px;
  background: #f9f9f9;
  display: inline-block;
  margin-right: 2px;
  margin-left: 2px;

  color: black;
}

#piano div span {
  position: absolute;
  bottom: 0.5em;
  width: 100%;
  text-align: center;
  pointer-events: none;
}

#piano div[data-note='E'],
#piano div[data-note='B'] {
  margin-right: 0;
}

#piano div[data-note$='#'] {
  background-color: #333;
  height: 65%;
  width: 24px;
  margin-left: calc(-12px - 1px);
  margin-right: calc(-12px - 1px);
  z-index: 1;
  bottom: 35%;
}

#piano div.pressed {
  background-color: #aaa;
}


.waveform-container {
  max-width: 200px;
}

.trace-container {
  display: inline-block;
}

code.trace-binary + code.trace-text {
  margin-left: 5px;
}

code.trace-binary + code.trace-text:before {
  content: '=';
  padding-right: 10px;
}