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The holy grail of the web design layout: Flexbox. It is the strongest tool to align an item, the duo relative-absolute. You can force the position of WHATEVER you want using this duo, something as small as an icon or as big as your <main>. You can create as much <div>'s as you desire to stretch the whole viewport. You need to define a general margin class so your elements will have their own well-defined space. The same goes for padding, you can play with the numbers of the top, bottom, left and right attributes.