User blog comment:Brandon Rhea/Why Fandom Evolves: A Look Ahead in 2017/@comment-1474707-20170111181000/@comment-20644-20170111183331

The mobile skin and apps do have much more standardized CSS, but a lot of what custom CSS is used for doesn't translate well to mobile devices. A big reason for that is because it can affect page load time, which is crucial on mobile.

What we feel we need to do more of moving forward is work with communities on finding ways to display and organize content so it's tailored to the most amount of people, rather than trying to duplicate a desktop experience on mobile.