Show Color Preview in LESS Files

 I have a LESS file that imports another LESS file.

@import "variables.less";

If I use a color variable, the color does not show in the gutter like regular color values.

.main {

    color: @main-color;  // no color preview

    color: #FFFFFF;  // color preview

}

Is there a problem with my configuration?  I am using IntelliJ 15.0.4.