superset-frontend/packages/superset-frontend/src/dashboard/stylesheets/components/divider.less

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
.dashboard-component-divider {
  width: 100%;
  padding: 8px 0; /* this is padding not margin to enable a larger mouse target */
  background-color: transparent;
}

.dashboard-component-divider:after {
  content: '';
  height: 1px;
  width: 100%;
  background-color: @gray-light;
  display: block;
}

.new-component-placeholder.divider-placeholder:after {
  content: '';
  height: 2px;
  width: 100%;
  background-color: @gray-light;
}

.dragdroppable .dashboard-component-divider {
  cursor: move;
}