text: const map = new carto.Map({
      container: 'map',
      background: 'black'
  });
  
  const source = new carto.source.GeoJSON(sources['multi-line-string']);
  const viz = new carto.Viz('width: 30');
  const layer = new carto.Layer('layer', source, viz);
  
  layer.addTo(map);
  layer.on('loaded', () => {
      window.loaded = true;
  });
  