Did an initial first round interview at my school's career center. First interview was mostly fit type questions. From "Why Citigroup?" to some basic questions about my interests and resume. Was invited for superday that same week. Met with 3 different seniors during superday. Went well with 2/3 of the seniors. The second senior grilled me with technical questions and I flustered because I had not prepared enough (learned my lesson since then). Now that I look back on it, the questions were very simple (linking the three accounting sheets, simple PV questions, etc.). Overall a good process and I learned a lot from the experience since then.