Bold some horizontal borders in the datatable

I need to split a table row (to separate some groups).
How do some horizontal borders in the datatable with thick bold lines?
Is that possible?

You can apply a custom CSS-style to the rows. Check the snippet:

http://webix.com/snippet/ffec1aff

Listopad, Thank you so much!


Спасибо большое за помощь.

The new little problem emerged.
I need your’s advice/help.

When cells is selected the line border is disappear.
Do it may be fixed? Is it difficult?

see snippet:
http://webix.com/snippet/e07a5d6b

http://webix.com/snippet/9b1315e7

It’s Great!

chris, you - a magician !!!

Many thanks to you!