superset-frontend/packages/superset-frontend/src/dashboard/stylesheets/grid.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.
 */

/* this is the ParentSize wrapper */
.grid-container > div:first-child {
  height: inherit !important;
}

.grid-content {
  display: flex;
  flex-direction: column;
}

/* gutters between rows */
.grid-content > div:not(:only-child):not(:last-child):not(.empty-droptarget) {
  margin-bottom: 16px;
}

/* Editing guides */
.grid-column-guide {
  position: absolute;
  top: 0;
  min-height: 100%;
  background-color: fade(@indicator-color, @opacity-light);
  pointer-events: none;
  box-shadow: inset 0 0 0 1px fade(@indicator-color, @opacity-medium-heavy);
}

.grid-row-guide {
  position: absolute;
  left: 0;
  bottom: 2;
  height: 2;
  background-color: @indicator-color;
  pointer-events: none;
  z-index: @z-index-above-dashboard-charts;
}