.dunetrack {
  position: relative;
  user-select: none;
  -o-user-select: none;
  -ms-user-select: none;
  -moz-user-select: none;
  -webkit-user-select: none;
  margin: 0;
  height: 24px;
  padding: 0;
  line-height: 24px;
  box-sizing: border-box;
  display: none;
  margin-top: 2px;
}

.dunetrack > span.holder {
  background: #d4d4d4;
  position: absolute;
  top: 0;
  left: 0;
  min-width: 100%;
  height: 24px;
  padding: 0 5px;
  line-height: 24px;
  box-sizing: border-box;
  text-align: center;
  vertical-align: top;
  border-radius: 0 2px 2px 0;
  box-sizing: border-box;
  cursor: pointer;
  transition: all 0.3s;
  white-space: nowrap;
}

.dunetrack > span.holder > span.fold {
  position: absolute;
  right: 100%;
  bottom: 0;
  width: 0;
  height: 0;
  border-width: 16px 0 0 24px;
  border-style: solid;
  border-color: #d4d4d4 transparent;
}

.dunetrack > span.holder > span.fold::before {
  content: ' ';
  position: absolute;
  background: #d4d4d4;
  height: 8px;
  width: 24px;
  bottom: 16px;
  right: 0;
  border-radius: 2px 0 0 0;
}

.dunetrack > span.holder > span.fold::after {
  content: ' ';
  position: absolute;
  right: 100%;
  bottom: 0;
  width: 0;
  height: 0;
  border-width: 16px 0 0 24px;
  border-style: solid;
  border-color: rgba(0, 0, 0, 0.1) transparent;
  box-shadow: 1px -1px 1px rgba(0, 0, 0, 0.25);
}

.dunetrack.reveal {
  user-select: all;
  -o-user-select: all;
  -ms-user-select: all;
  -moz-user-select: all;
  -webkit-user-select: all;
}

.dunetrack.reveal > span.holder {
  opacity: 0;
  pointer-events: none;
  left: 100% !important;
}