div#container {
  position: fixed;
  right: 0;
  bottom: 0;
  left: 0;
  height: 64px;
}
div.audio-player-container {
  position: relative;
  height: 100%;
}
div.audio-player {
  width: 64px;
  height: 32px;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  flex-direction: row;
  background-color: #111;
}
div#box-play-head {
  margin: 0 8px;
  width: 200px;
  height: 32px;
  display: flex;
  align-items: center;
}
.svg-btn {
  fill: #333;
}
.svg-btn:hover {
  fill: #999;
}
#btn-pause-group {
  display: none;
}
div.btn {
  cursor: pointer;
}
.fadeIn {
  opacity: 1;
  transition: opacity 250ms linear;
}
.fadeOut {
  opacity: 0;
  transition: opacity 400ms linear;
}