15 + Flexbox Background Image Desktop Wallpaper. It usely consists of a large background image and a title. For this example I've also added a header with logo and menu button and two buttons for some call to action.

21 + Flexbox Background Image HD Wallpapers
These terminologies will be used throughout this guide.
Power Of "Flexbox" CSS
flexbox - CSS Flex navbar - how? - Stack Overflow
CSS Flexbox #9. The align-content Property
CSS3 FlexBox - CSS3gen
CSS Flexbox #15. How to Create a Megamenu With Flexbox
css - HTML Flexbox Gallery - Stack Overflow
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