pub fn svg_attr_len_px(tag: &str, name: &str) -> Option<f64>Expand description
An SVG length attribute in CSS px. A unitless value is user units, i.e. px.
None for anything that isn’t an absolute length (%, em, ex, …) —
those are resolved against a viewport we don’t have, so the caller must fall
back to the viewBox rather than treat the bare number as pixels.