Hard proof that a dress shirt and light blue skinny jeans are amazing when worn together in a laid-back outfit. Add a pair of tan monks to the equation to avoid looking too casual. So if you're looking for a stylish yet mature outfit, this one fits the bill.
For smart style with a modern finish, make a dress shirt and grey gingham dress pants your outfit choice. Add a pair of tan monks to this getup and the whole ensemble will come together. You can take cues from outfits like this if you've hit your 30s and you want to take a more mature direction in your personal style.