Please document the difference between the operator '%' and the built-in function 's()'

[nanarino]

To reproduce:

_rgb1(color)
    s('rgb(%s)', color)
_rgb2(color)
    'rgb(%s)'%color
:root
    --gray-10 29 33 41
    .box1
        --box-shadow-divider-bottom inset 0px -1px 0px 0px _rgb1(var(--gray-10) \/ .05)
    .box2
        --box-shadow-divider-bottom inset 0px -1px 0px 0px _rgb2(var(--gray-10) \/ .05)

Current behavior:

_rgb1 is ok ; _rgb2 opacity value / .05 ​​are lost

Expected behavior:

For newcomers, this is a confusing feature isn't it.
Please document the difference between the operator '%' and the built-in function 's()'🙏
doc

Environment information:

• stylus version: 0.59.0
• nodejs version: v18.16.0

** others **

👀I am new hand, to learning stylus
see file