Hi Aspirant

The marks required for civil branch or any other branch depends on not only on marks rather depends on various factor:

1.difficulty level of the paper

2.Number of students appeared

Both of these are the basis of cut off of the paper .And cut off of the paper can determine your rank and college you will get in .You will have to qualify in each subjects to overall qualify in JEE Advance.

You can check the previous year trends of marks as well as rank.Visit the link given below:

https://engineering.careers360.com/articles/jee-advanced-rank-list

https://engineering.careers360.com/articles/jee-advanced-cutoff-for-iit-guwahati

hope this helps you.