Conditional Formatting in Line or Area Graph

Hello,

I have a one problem in Conditional Formatting in Line Graph.

Example:  

When I selected one Primary Scheme it has one Scheme Start Date and One Scheme End Date.

Scheme Start Date  : 1-7-2022
Scheme End Date  : 11-7-22

so Duration Between Scheme Start and End Date is 10 Days.

After that I Create a Two coloum in My Dataset one is Pre Scheme Date and Post Scheme Date Which is Before and After Scheme Days

Pre Date : 21-06-2022
Post Date : 21-07-2022

Now I want a Trend Line between Pre and Post Date and get Coditional Formatting between Scheme Start and Stop Date ....Like i highlight the trend between scheme Start and Stop Date.