The flex-grow CSS property sets the flex grow factor to the provided number.
object.style.flexGrow = "value";
<'flex-grow'> = <number [0,∞]>
<number [0, ∞]>
An integer or zero or more decimal digits followed by a dot (.) followed by one or more decimal digits. The first character may be preceded by a positive sign (+). The last character may be succeeded by an exponent (e or E) and an integer.