Indian stock markets closed Tuesday on a subdued note, with the Sensex and Nifty ending marginally lower amid thin year-end trading volumes. Persistent foreign institutional investor (FII) outflows and mixed global cues weighed on sentiment, despite some gains in PSU banks, metals, and auto stocks. Investors remained cautious, balancing sector-specific buying against profit-taking in some heavyweights, leading to a range-bound trading session.