Canvas element styling with d3.carto.map does not use d3.selectAll like SVG element styling because these aren't SVG elements.
This relies on using cartoLayer.markerColor() and cartoLayer.markerSize() and setting them to function based on the data. If you don't set markerColor, then it will rely on CSS styling of the associated class.
Modified http://d3js.org/d3.v3.min.js to a secure url
Modified http://d3js.org/topojson.v1.min.js to a secure url
Modified http://d3js.org/d3.geo.projection.v0.min.js to a secure url
Updated missing url http://bl.ocks.org/emeeks/raw/f3105fda25ff785dc5ed/tile.js to /emeeks/f3105fda25ff785dc5ed/example/tile.js
Updated missing url http://bl.ocks.org/emeeks/raw/f3105fda25ff785dc5ed/d3.quadtiles.js to /emeeks/f3105fda25ff785dc5ed/example/d3.quadtiles.js
Updated missing url http://bl.ocks.org/emeeks/raw/f3105fda25ff785dc5ed/d3.geo.raster.js to /emeeks/f3105fda25ff785dc5ed/example/d3.geo.raster.js
Updated missing url https://rawgit.com/emeeks/d3-carto-map/master/d3.carto.map.js to https://cdn.jsdelivr.net/gh/emeeks/d3-carto-map/d3.carto.map.js
https://d3js.org/d3.v3.min.js
https://d3js.org/topojson.v1.min.js
https://d3js.org/d3.geo.projection.v0.min.js
https://bl.ocks.org/emeeks/raw/f3105fda25ff785dc5ed/tile.js
https://bl.ocks.org/emeeks/raw/f3105fda25ff785dc5ed/d3.quadtiles.js
https://bl.ocks.org/emeeks/raw/f3105fda25ff785dc5ed/d3.geo.raster.js
https://rawgit.com/emeeks/d3-carto-map/master/d3.carto.map.js