Draw the strokes like the column-header-cell instead of using background-image

[fabiiomiiguel]

Hello :)

Maybe it will be nice, if instead of using sg-columns svelte-1clwlpk with background-image, you draw one row with something like column-header-cell with height 100%. That will allow to style the strokes with css.

What you think?

[ANovokmet]

This is actually how it used to be, but since the main goal for svelte-gantt I had, was for it to be as performant as possible, and these lines can be the cause of way too many divs in the DOM being created. What I should do is to provide more options for styling these columns.