Style border every days

Can I style the border after each day?

Thank you!

Hi @linhtv97,
In order to change the border color of the chart-cell from css, you should change the .gantt_task_cell rule, like in this code fragment:
.gantt_task_cell { border-right: 1px solid red; }
Here is the snippet that demonstrates how does it work(HTML tab):
Also, you can work with cells styles more flexible, using gantt.templates.timeline_cell_class
Here is an example:
If you have config with hours scale, you may want to change only the end/start day cells, in this snippet, you can see how it could be implemented: