ul, li {
  display: block;
  margin: 0;
  padding: 0;
}

  li {
    list-style-type: none;
  }

.group-title, .tab {
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

  .group.active .group-title, .tab.active {
    font-weight: bold;
  }

  .group:hover .group-title {
    padding-right: 15px;
  }

.group, .tab {
  border-radius: 3px;
  border: 1px solid transparent;
  cursor: pointer;
  padding: 5px;
  position: relative;
}

  .group:hover, .tab:hover {
    background-color: #eaeaea;
    border-color: #d3d3d3;
  }

.tab-list {
  display: none;
  margin-top: 5px;
}

  .expanded .tab-list {
    display: block;
  }

.expanded .group-title {
  border-bottom: 1px solid #d3d3d3;
  padding-bottom: 5px;
}

.group-controls {
  display: none;
  font-size: 120%;
  position: absolute;
  right: 5px;
  top: 4px;
}

.group:hover .group-title {
  padding-right: 55px;
}

  .group:hover .group-controls {
    display: inline-block;
  }

ul, li {
  display: block;
  margin: 0;
  padding: 0;
}

  li {
    list-style-type: none;
  }

.group-title, .tab {
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

  .group.active .group-title, .tab.active {
    font-weight: bold;
  }

  .group:hover .group-title {
    padding-right: 15px;
  }

.group, .tab {
  border-radius: 3px;
  border: 1px solid transparent;
  cursor: pointer;
  padding: 5px;
  position: relative;
}

  .group:hover, .tab:hover {
    background-color: rgba(0, 0, 0, 0.06);
    border-color: rgba(0, 0, 0, 0.12);
  }

.tab-list {
  display: none;
  margin-top: 5px;
}

  .expanded .tab-list {
    display: block;
  }

.expanded .group-title {
  border-bottom: 1px solid rgba(0, 0, 0, 0.12);
  padding-bottom: 5px;
}

.group-controls {
  display: none;
  font-size: 120%;
  position: absolute;
  right: 5px;
  top: 4px;
}

.group:hover .group-title {
  padding-right: 55px;
}

  .group:hover .group-controls {
    display: inline-block;
  }

Use semi transparent black to support color themes
Use semi transparent black to support color themes
