Set pitch and bearing
Map options extend CameraOptions, so you can set more than just center and zoom
<!DOCTYPE html>
    <meta charset='utf-8' />
    <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
    <script src=''></script>
    <link href='' rel='stylesheet' />
        body { margin:0; padding:0; }
        #map { position:absolute; top:0; bottom:0; width:100%; }

<div id='map'></div>
mapboxgl.accessToken = '<your access token here>';
var map = new mapboxgl.Map({
    container: 'map',
    style: 'mapbox://styles/mapbox/streets-v9',
    center: [-73.5804, 45.534830],
    pitch: 60, // pitch in degrees
    bearing: -60, // bearing in degrees
    zoom: 10

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