style.scss

$white: #c0c0c0;
$background: rgba(128, 128, 128, 0.25);

html,
body {
  margin: 0;
  padding: 0;
  overflow: hidden;
  height: 100%;
  width: 100%;
  background: #000;
  font-family: Helvetica, sans-serif;
}

button,
label {
  box-sizing: border-box;
  appearance: none;
  border: none;
  min-width: 5rem;
  color: $white;
  font-size: 1rem;
  padding: 0.5rem;
  border-radius: 0.125rem;
  border: 0.0675em solid #404040;
  background: $background;
  box-shadow: 0 0.125em #101010;
  text-shadow: 0 0.0625em #202020;
  user-select: none;
  cursor: pointer;
  &:hover {
    background: rgba(128, 128, 128, 0.5);
  }

  &#webaudio {
    position: absolute;
    bottom: 5rem;
    left: 2rem;
  }
}

#tone-content {
  /* Magenta and Tone.js */
  width: calc(66.66% - 8rem);
  max-width: 24rem;
  position: absolute;
  bottom: 5rem;
  left: 50%;
  transform: translateX(-50%);
  color: white;
  code {
    position: absolute;
    top: 100%;
    &#playback {
      right: 0;
      cursor: pointer;
    }
    &#score {
      left: 0;
    }
  }

  details {
    color: #fff;
    user-select: none;
    position: relative;
    padding-bottom: 1em;
    summary {
      position: absolute;
      bottom: 0;
      width: 100%;
    }
    textarea#midiJSON {
      font-family: monospace;
      height: 8em;
      width: 100%;
      box-sizing: border-box;
    }
  }

  #midiSequence {
    position: absolute;
    bottom: 3rem;
    width: 100%;
    height: 6rem;
    overflow: hidden;
    overflow-x: auto;
    z-index: -1;
    #magenta {
      display: block;
      width: auto !important;
      height: 100% !important;
      //image-rendering: pixelated;
      pointer-events: none;
    }
  }

  label#midiLabel {
    position: relative;
    display: block;
    width: 100%;
    text-align: center;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    border-style: dashed;
    input#midiFile {
      opacity: 0;
      position: absolute;
      width: 100%;
      height: 100%;
      top: 0;
      left: 0;
      z-index: -1;
    }
  }
  line-height: 1;
}

* {
  /* Works on Firefox */
  scrollbar-width: thin;
  scrollbar-color: $white $background;

  /* Works on Chrome, Edge, and Safari */
  &::-webkit-scrollbar {
    width: 0.5rem;
    height: 0.5rem;
  }

  &::-webkit-scrollbar-track {
    background: $background;
  }

  &::-webkit-scrollbar-thumb {
    background-color: $white;
    border: 0.125rem solid $background;
  }
}

button,
label,
details,
textarea {
  font-size: 0.75rem;
}