guage governing permissions and
limitations under the License.
-->
<style>
  howto-tab {
    border: 1px solid black;
    padding: 20px;
  }
  howto-panel {
    padding: 20px;
    background-color: lightgray;
  }
  howto-tab[selected] {
    background-color: bisque;
  }

  /**
   * If JavaScript does not run, the element will not match `:defined`.
   * In that case this style adds spacing between tabs and previous panel.
   */
  howto-tabs:not(:defined), howto-tab:not(:defined), howto-panel:not(:defined) {
