i have a form that calculates a width input & Height Input.

It then calculates area and multiplies it by the selected material option.

i then add this formula to a "product field" and this seems to give me my correct values on the Total before i add it to my woocommerce basket.

What i wanted to know is how do i hide the "product field ID 19" from customers view, yet remain operational in its formula calculations.

i tried `.hidden {visibility: hidden!important; }`

in my wordpress themes custom .css file but its still visable, if i use conditional logic for something bizar like `if total area = 999999999`

but then the calculations dont give me the correct values but it hides the field.

am i doing something wrong here?