/resp/ - Responsive Design

someone told me today that we should just use width: 1200px; for the main wrapper because it's "easier to track". i can't even. it's not easier when you're staring at a broken horizontal scroll on a small tablet. if you aren't using max-width, you're basically just making a desktop site and hoping for the best. modern smart developers actually use percentages or intrinsic sizing so things don't just clip into nothingness. it's such an amateur move to ignore how the viewport actually behaves. what's your go-to for preventing that horizontal overflow mess?