THtmlHotTrack.ColHeadingStyle Property
Style to apply to the heading columns when the mouse is over a cell. You can use any css style here. Set it to empty if you don't want to highlight the headings. Note that highlighting the columns will increase the size of the generated file, so leave this one empty if you want to minimize the file size. Row and cell hot-track won't increase the file size.
Syntax
Unit: FlexCel.Render
property THtmlHotTrack.ColHeadingStyle: string