How to change road color in mapbox basic map in plotly.js

The roads are useful references for the map I am trying to create (scattermapbox over choroplethmapbox). However, the white roads are too distracting. Is there a way to change the color of the roads to gray? Here is the layout config:
var layout = {
scope: ‘usa’,
dragmode: “zoom”,
margin: { r: 0, t: 0, b: 0, l: 0, pad: 2 },
mapbox: { style: ‘basic’,
center: {lon: -98.4, lat: 39.5},
zoom: 3,

I think an alternative is to change the outline color of the markers to a dark color. Anyone knows a way to do that? I don’t seem to be able to find a way to do it.