With mobile accounting for well over half of global web traffic, designing for the small screen first is no longer a stylistic preference — it is the only order that produces honest priorities.
Mobile-first forces a content hierarchy. When there is room for one call to action above the fold, the team has to agree on which one. That agreement then improves the desktop layout too.
Practically: design the narrow layout at real device widths, not a scaled artboard. Test touch targets at 44px minimum. Assume a slow network and design the loading state as a first-class screen rather than a spinner.
The desktop layout then becomes an enhancement — more columns, more breathing room, richer imagery — rather than a compromise that gets progressively amputated.
