Homepride Flour created a stunning photographic website for the iconic product. Discover the products, heritage, recipes and community that have powered Great British Baking since 1964. The canvas can be a desktop, mobile screen or anything in between. Pixel density can also vary, so we need units that are flexible and work everywhere. That's where relative units like percents come in handy. So making something 50% wide means it will always take half of the screen (or viewport, which is the size of the opened browser window).