Flex Basis

Specifies the initial length of a flexible item. This will override any width value, unless flex-basis is set to auto (see below).

Value Description
autoDefault. The existing width of the flexible item is honoured. If the item has no explicit width set, the width will be according to its content.
(numeric)E.g. '400' would set the flex-basis to 400 pixels. Other commonly used units include 'em' and '%'. So you could enter '50%'

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