<style>
.boxdraw {
    background: rgba(56,135,190,0.1);
    border: 2px solid #3887be;
    position: absolute;
    top: 0;
    left: 0;
    width: 0;
    height: 0;
}
</style>

<div id='map'></div>

<script>
var map = new mapboxgl.Map({
    container: 'map',
    style: 'mapbox://styles/mapbox/streets-v9',
    center: [-98, 38.88],
    minZoom: 2,
    zoom: 3
});

// Disable default box zooming.
map.boxZoom.disable();

// Create a popup, but don't add it to the map yet.
var popup = new mapboxgl.Popup({
    