app/scripts/terrain/terrain.directive.html
<span ng-hide='tr.mobile' class="interface-visible interface-clickable ewa-checkbox">
<!--
Terrain?
<input type="checkbox" ng-model="tr.terrain">
-->
<button ng-click="tr.toggleTerrain()" class="icon-big terrain-icon" ng-class="{active: tr.terrain}" title="Terrain"></button>
</span>