src/driver.scss

div#driver-popover-item {
  display: none;
  position: absolute;
  background: white;
  color: #2d2d2d;
  margin: 0;
  padding: 15px;
  border-radius: 5px;
  min-width: 250px;
  max-width: 300px;
  box-shadow: 0 1px 10px rgba(0, 0, 0, 0.4);
  z-index: 1000000000;

  .driver-popover-tip {
    border: 5px solid white;
    content: '';
    position: absolute;

    &.bottom {
      bottom: -10px;
      border-top-color: white;
      border-right-color: transparent;
      border-bottom-color: transparent;
      border-left-color: transparent;
    }

    &.left {
      left: -10px;
      top: 10px;
      border-top-color: transparent;
      border-right-color: white;
      border-bottom-color: transparent;
      border-left-color: transparent;
    }

    &.right {
      right: -10px;
      top: 10px;
      border-top-color: transparent;
      border-right-color: transparent;
      border-bottom-color: transparent;
      border-left-color: white;
    }

    &.top {
      top: -10px;
      border-top-color: transparent;
      border-right-color: transparent;
      border-bottom-color: white;
      border-left-color: transparent;
    }
  }

  .driver-popover-footer {
    display: block;
    clear: both;
    margin-top: 5px;

    a {
      display: inline-block;
      padding: 3px 10px;
      border: 1px solid #d4d4d4;
      text-decoration: none;
      text-shadow: 1px 1px 0 #fff;
      color: #2d2d2d;
      font: 11px/normal sans-serif;
      cursor: pointer;
      outline: 0;
      background-color: #f1f1f1;
      border-radius: 2px;
      zoom: 1;
      margin: 10px 0 0;
    }

    a.driver-disabled {
      color: #808080;
      cursor: default;
      pointer-events: none;
    }

    .driver-close-btn {
      float: left;
    }

    .driver-btn-group {
      float: right;
    }
  }

  .driver-popover-title {
    font: 19px/normal sans-serif;
    margin: 0 0 5px;
    font-weight: bold;
    display: block;
    position: relative;
    line-height: 1.5;
    zoom: 1;
  }

  .driver-popover-description {
    margin-bottom: 0;
    font: 14px/normal sans-serif;
    line-height: 1.5;
    color: #2d2d2d;
    font-weight: normal;
    zoom: 1;
  }
}