Basic CSS (Flexbox)

main axis - The main axis of a flex container is the primary axis along which flex items are laid out

Beware, it is not necessarily horizontal; it depends on the flex-direction property (see below).

Order

By default, flex items are laid out in the source order. However, the order property controls the order in which they appear in the flex container.

flex-wrap: wrap;

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. 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.

cross axis - The axis perpendicular to the main axis is called the cross axis

Its direction depends on the main axis direction.

[attr=value]

Used to style boxes in class selectors

Flexbox Box Model

a layout mode for using flexible boxes in user interfaces

[type='radio'] { margin: 20px 0px 20px 0px; }

changes the margins of all elements with the attribute type and a corresponding value of radio

background-color property

configures the background color of an element, repeating property for each flex-item

Main axis

going to the right, horizontal line, x (flex-direction: row / column) 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.

Alignment

how the edges of a line, paragraph, object, or table are positioned horizontally and vertically between the margins or on a page

flex-direction: column;

items arranged from top to bottom

style elements

originally, we styled classes and now we're going to style elements

wrapping

paper or other material used to cover or protect something

.box

selector for multiple items to add width, text-shadow, text-align, color, etc.

Auto(prefix)

self

flex property

used to customize the size of each flex item

nested

A ______ class is a class declared within the body of another class

Cross-axis

A line or center line that crosses a primary axis, typically perpendicular to the primary axis, x and y (flex-direction: row / column)

flex-direction

Controls the direction of the child boxes in the parent box; also affects the flex-pack property, (flex-direction is set to row on default) 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

cross-start | cross-end

Flex lines are filled with items and placed into the container starting on the cross-start side of the flex container and going toward the cross-end side

flex-grow

Flexible Box Layout: Specifies how much the item will grow relative to the rest. This defines the ability for a flex item to grow if necessary. It accepts a unitless value that serves as a proportion. It dictates what amount of the available space inside the flex container the item should take up. If all items have flex-grow set to 1, the remaining space in the container will be distributed equally to all children. If one of the children has a value of 2, the remaining space would take up twice as much space as the others (or it will try to, at least). } Negative numbers are invalid.

flex-shrink

Flexible Box Layout: Specifies how the item will shrink relative to the rest

align-items

Flexible Box Layout: Specifies the alignment for items inside a flexible container.

flexbox

Offers flexible layouts for UI design.

reordering

Organizing and clarifying information of spreadsheet by sequential placement of tabs and slides

justify-content

Specifies the alignment between the items inside a flexible container when the items do not use all available space

justify-content

Specifies the alignment between the items inside a flexible container when the items do not use all available space This defines the alignment along the main axis. It helps distribute extra free space leftover 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 | start | end | left | right ... + safe | unsafe; } flex-start (default): items are packed toward the start of the flex-direction. flex-end: items are packed toward the end of the flex-direction. start: items are packed toward the start of the writing-mode direction. end: items are packed toward the end of the writing-mode direction. left: items are packed toward left edge of the container, unless that doesn't make sense with the flex-direction, then it behaves like start. right: items are packed toward right edge of the container, unless that doesn't make sense with the flex-direction, then it behaves like start. 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. Note that that browser support for these values is nuanced. For example, space-between never got support from some versions of Edge, and start/end/left/right aren't in Chrome yet. MDN has detailed charts. The safest values are flex-start, flex-end, and center. There are also two additional keywords you can pair with these values: safe and unsafe. Using safe ensures that however you do this type of positioning, you can't push an element such that it renders off-screen (e.g. off the top) in such a way the content can't be scrolled too (called "data loss").

align-content

Specifies the alignment between the lines inside a flexible container when the items do not use all available space

align-self

Specifies the alignment for selected items inside a flexible container

flex-basis

Specifies the initial length of a flexible item This defines the default size of an element before the remaining space is distributed. It can be a length (e.g. 20%, 5rem, etc.) or a keyword. The auto keyword means "look at my width or height property" (which was temporarily done by the main-size keyword until deprecated). The content keyword means "size it based on the item's content" - this keyword isn't well supported yet, so it's hard to test and harder to know what its brethren max-content, min-content, and fit-content do.

cross size - The width or height of a flex item, whichever is in the cross dimension, is the item's cross size

The cross size property is whichever of 'width' or 'height' that is in the cross dimension.

main size - A flex item's width or height, whichever is in the main dimension, is the item's main size

The flex item's main size property is either the 'width' or 'height' property, whichever is in the main dimension.

align-content

This aligns a flex container's lines within when there is extra space in the cross-axis, similar to how justify-content aligns individual items within the main-axis. Note: this property has no effect when there is only one line of flex items. .container { align-content: flex-start | flex-end | center | space-between | space-around | space-evenly | stretch | start | end | baseline | first baseline | last baseline + ... safe | unsafe; } flex-start / start: items packed to the start of the container. The (more supported) flex-start honors the flex-direction while start honors the writing-mode direction. flex-end / end: items packed to the end of the container. The (more support) flex-end honors the flex-direction while end honors the writing-mode direction. center: items centered in the container space-between: items evenly distributed; the first line is at the start of the container while the last one is at the end space-around: items evenly distributed with equal space around each line space-evenly: items are evenly distributed with equal space around them stretch (default): lines stretch to take up the remaining space The safe and unsafe modifier keywords can be used in conjunction with all the rest of these keywords (although note browser support), and deal with helping you prevent aligning elements such that the content becomes inaccessible.

align-self

This allows the default alignment (or the one specified by align-items) to be overridden for individual flex items. Please see the align-items explanation to understand the available values. .item { align-self: auto | flex-start | flex-end | center | baseline | stretch; } Note that float, clear and vertical-align have no effect on a flex item.

display: flex;

This defines a flex container; inline or block depending on the given value. It enables a flex context for all its direct children. Note that CSS columns have no effect on a flex container.

align-items

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 | first baseline | last baseline | start | end | self-start | self-end + ... safe | unsafe; } stretch (default): stretch to fill the container (still respect min-width/max-width) flex-start / start / self-start: items are placed at the start of the cross axis. The difference between these is subtle, and is about respecting the flex-direction rules or the writing-mode rules. flex-end / end / self-end: items are placed at the end of the cross axis. The difference again is subtle and is about respecting flex-direction rules vs. writing-mode rules. center: items are centered in the cross-axis baseline: items are aligned such as their baselines align The safe and unsafe modifier keywords can be used in conjunction with all the rest of these keywords (although note browser support), and deal with helping you prevent aligning elements such that the content becomes inaccessible.

flex-flow

This is a shorthand for the flex-direction and flex-wrap properties, which together define the flex container's main and cross axes. The default value is row nowrap.

flex

This is the shorthand for flex-grow, flex-shrink and flex-basis combined. The second and third parameters (flex-shrink and flex-basis) are optional. The default is 0 1 auto, but if you set it with a single number value, it's like 1 0. .item { flex: none | [ <'flex-grow'> <'flex-shrink'>? || <'flex-basis'> ] } It is recommended that you use this shorthand property rather than set the individual properties. The shorthand sets the other values intelligently.