淡然 is a literary adjective meaning 'indifferent' or 'unruffled' — a state of being calmly detached from outcomes or emotions. It often describes a person's attitude toward success, failure, or praise, carrying a positive connotation of inner peace rather than coldness. You'll see it in phrases like 淡然一笑 ('a faint, indifferent smile') or 淡然处之 ('to deal with something with calm indifference').