CSS Flexible Box Layout is a module of CSS that defines a CSS box model optimized for user interface design. In the flex layout model, the children of a flex container can be laid out in any direction, and can “flex” their sizes, either growing to fill unused space or shrinking to avoid overflowing the parent. Both horizontal and vertical alignment of the children can be easily manipulated. Nesting of these boxes (horizontal inside vertical, or vertical inside horizontal) can be used to build layouts in two dimensions.
The flexCSS property is a shorthand property specifying the ability of a flex item to alter its dimensions to fill available space. Flex items can be stretched to use available space proportional to their flex grow factor or their flex shrink factor to prevent overflow.
The CSSflex-wrap property specifies whether flex items are forced into a single line or can be wrapped onto multiple lines. If wrapping is allowed, this property also enables you to control the direction in which lines are stacked.
The CSSorder property specifies the order used to lay out flex items in their flex container. Elements are laid out in the ascending order of the order value. Elements with the same order value are laid out in the order in which they appear in the source code.
The CSS3 Flexible Box, or flexbox, is a layout mode providing for the arrangement of elements on a page such that the elements behave predictably when the page layout must accommodate different screen sizes and different display devices. For many applications, the flexible box model provides an improvement over the block model in that it does not use floats, nor do the flex container's margins collapse with the margins of its contents.