Flex shorthand property

The flex property can have one of three keyword values:

• initial
• auto
• none

initial (flex: 0 1 auto)

• Growth: Doesn’t grow to absorb extra free space in the flex container.
• Shrinking: Shrinks to its minimum size to fit in the flex container.
• Sizing: The item is sized according to its width and height properties.
• Equivalent to flex: 0 1 auto

auto (flex: 1 1 auto)

• Growth: Grows to absorb extra free space in the flex container.
• Shrinking: Shrinks to its minimum size to fit in the flex container.
• Sizing: The item is sized according to its width and height properties.
• Equivalent to flex: 1 1 auto

none (flex 0 0 auto)

• Growth: Doesn’t grow to absorb extra free space in the flex container.
• Shrinking: Doesn’t shrink to its minimum size to fit in the flex container.
• Sizing: The item is sized according to its width and height properties.
• Equivalent to flex: 0 0 auto

Sources

• MDN Docs