slickgrid/controls/slick.columnpicker.css

.slick-columnpicker {
  border: 1px solid #718BB7;
  background: #f0f0f0;
  padding: 6px;
  -moz-box-shadow: 2px 2px 2px silver;
  -webkit-box-shadow: 2px 2px 2px silver;
  box-shadow: 2px 2px 2px silver;
  min-width: 150px;
  cursor: default;
  position:absolute;
  z-index:20;
	overflow:auto;
  resize: both;
}

.slick-columnpicker > .close {
  float: right;
}

.slick-columnpicker .title {
  font-size: 16px;
  width: 60%;
  border-bottom: solid 1px #d6d6d6;
  margin-bottom: 10px;
}

.slick-columnpicker li {
  list-style: none;
  margin: 0;
  padding: 0;
  background: none;
}

.slick-columnpicker input {
  margin: 4px;
}

.slick-columnpicker li a {
  display: block;
  padding: 4px;
  font-weight: bold;
}

.slick-columnpicker li a:hover {
  background: white;
}

/* Excluded item from Column Picker will be hidden */
.slick-columnpicker-list li.hidden {
  display: none;
}