Had been to a temple today with my wife. Spent almost 3 hours outdoors (no AC, no shopping, mostly walking, and some public transport by a tuktuk). It is 110 F here. So, minimally casual.
Chose to pair my magenta Polo with a dark wash denim (Levis 512; this is mid-waist, slim fit, and tapered leg). My new sling bag (blue canvas), brown belt, tan-leather strapped watch, and tan nubuck loafers complete the attire.