Constant style::values::computed::font::FONT_WEIGHT_FRACTION_BITS

pub const FONT_WEIGHT_FRACTION_BITS: u16 = 6;

font-weight: range 1..1000, fractional values permitted; keywords ‘normal’, ‘bold’ aliased to 400, 700 respectively.

We use an unsigned 10.6 fixed-point value (range 0.0 - 1023.984375)