Flex Layout is a CSS module for web page layout that provides a flexible way to arrange and align elements. Flex layout enables elements within a container to automatically resize and adapt to different screen sizes and device types.
Flex layout is enabled by applying the display: flex or display: inline-flex properties on the container. Child elements inside a container become flex items and are arranged according to the container's main and cross axes.
Following are some important concepts of flex layout:
- Main axis and cross axis: The main axis of the container is the direction in which the flex items are arranged, which can be horizontal (row) or vertical (column). The cross axis is the direction perpendicular to the main axis.
- Flex container properties: including flex-direction, flex-wrap, flex-flow, justify-content and align-items, etc., used to control the arrangement and alignment of Flex items.
- Flex item attributes: including flex-grow, flex-shrink, flex-basis, flex, and align-self, etc., used to control the flexibility and alignment of the flex item in the container.
By using these properties flexibly, we can achieve various layout effects, such as horizontal centering, vertical centering, and equal layout. Flex layout has become one of the commonly used layout methods in modern web development. It is easy to understand, flexible and practical, and is suitable for various scenarios.