Learn how to make your pages look great on both desktop and mobile. 1. Use Columns to center and align elements horizontally 2. Don't use more than 25px of Margins or Padding on Left and Right sides 3. Remember that background images (i.e. on Section) will crop. You can use Images. 4. Screen settings can be used to reveal or hide elements or sections per screen size. 5. Always toggle between the screen size previews to see how it looks while building an element or section. Don't wait until the end!