Constructing a gray colorscale in d3.js -

Constructing a gray colorscale in d3.js -

i'm trying build custom colorscale in d3.js. scale looks this:

var color = d3.scale.linear() .domain([ext[0], ext[1]]) .range(["#d1d1d1", "#000000"]);

values in domain : 500, 35676000

but when i'm calling color doesn't take in between color range.

.attr('fill', function(d, i){ homecoming color(i); })

d3.js