Properties for the Parent
(flex container)
Properties for the Children
(flex items)
display
This defines a flex container; inline or block depending on the given value. It enables a flex context for all its direct children.
.container {display: flex; /* or inline-flex */}
Note that CSS columns have no effect on a flex container.
flex-direction
the four possible values of flex-direction being shown: top to bottom, bottom to top, right to left, and left to right
This establishes the main-axis, thus defining the direction flex items are placed in the flex container. Flexbox is (aside from optional wrapping) a single-direction layout concept. Think of flex items as primarily laying out either in horizontal rows or vertical columns.
.container {flex-direction: row | row-reverse | column | column-reverse;}
row (default): left to right in ltr; right to left in rtl
row-reverse: right to left in ltr; left to right in rtl
column: same as row but top to bottom
column-reverse: same as row-reverse but bottom to top
flex-wrap
two rows of boxes, the first wrapping down onto the second
By default, flex items will all try to fit onto one line. You can change that and allow the items to wrap as needed with this property.
.container{flex-wrap: nowrap | wrap | wrap-reverse;}
nowrap (default): all flex items will be on one line
wrap: flex items will wrap onto multiple lines, from top to bottom.
wrap-reverse: flex items will wrap onto multiple lines from bottom to top.
There are some visual demos of flex-wrap here.
justify-content
flex items within a flex container demonstrating the different spacing options
This defines the alignment along the main axis. It helps distribute extra free space left over when either all the flex items on a line are inflexible, or are flexible but have reached their maximum size. It also exerts some control over the alignment of items when they overflow the line.
.container {justify-content: flex-start | flex-end | center | space-between | space-around | space-evenly;}
flex-start (default): items are packed toward the start line
flex-end: items are packed toward the end line
center: items are centered along the line
space-between: items are evenly distributed in the line; first item is on the start line, last item on the end line
space-around: items are evenly distributed in the line with equal space around them. Note that visually the spaces aren’t equal, since all the items have equal space on both sides. The first item will have one unit of space against the container edge, but two units of space between the next item because that next item has its own spacing that applies.
space-evenly: items are distributed so that the spacing between any two items (and the space to the edges) is equal.
align-items
demonstration of differnet alignment options, like all boxes stuck to the top of a flex parent, the bottom, stretched out, or along a baseline
This defines the default behavior for how flex items are laid out along the cross axis on the current line. Think of it as the justify-content version for the cross-axis (perpendicular to the main-axis).
.container {align-items: stretch | flex-start | flex-end | center | baseline;}
stretch (default): stretch to fill the container (still respect min-width/max-width)
flex-start: cross-start margin edge of the items is placed on the cross-start line
flex-end: cross-end margin edge of the items is placed on the cross-end line
center: items are centered in the cross-axis
baseline: items are aligned such as their baselines align