No engineering branch is difficult if you have a casual attitude towards it. Every engineering ranch is challenging if you have a robust attitude towards it. The same is true for civil engineering. I took my B.Tech casually and studied only before the exam. I never found civil a difficult branch. Some of friends spent day and night studying and they found civil very challenging.
To pass in engineering, one only needs to memorize and learn superficially. To succeed in engineering, one has to go into the depths of the subject.