This combination of a black and white horizontal striped cardigan and a white crew-neck t-shirt is hard proof that a safe casual outfit can still look seriously chic. For something more on the classy end to finish off this outfit, complete your look with a pair of black leather heeled sandals. Keep this combo in your head come warmer days, and rest assured, you'll save a ton of time racking your brain for a look on more than one occasion.