ant-design/style/components/timepicker/Panel.less

.@{timepicker-prefix-cls}-panel-inner {
  display: inline-block;
  position: relative;
  outline: none;
  border: 1px solid #ccc;
  list-style: none;
  font-size: 12px;
  text-align: left;
  background-color: #fff;
  border-radius: @border-radius-base;
  box-shadow: 0 1px 5px #ccc;
  background-clip: padding-box;
  border: 1px solid #ccc;
  line-height: 1.5;
}