I couldn't get support to show me where this was because they don't do custom code but I figured it out on my own so I thought I would share in case others are interested. I am using the "Warehouse" theme and therefore instructions may be specific to this theme.
I wanted the SKU to be at least 20Px and I wanted it to display in red...
In the theme.scss.liquid file you locate .product-meta__reference
the code you want will look like this:
You will change it to this.
You can choose whatever color class you want I chose this one because It was already the color I was looking for.
You can assign whatever color class you want and then once you have done this the color itself can be adjusted along with everything else assigned to it via the theme visual editor.
Please share your site url so that i can check and let you know.
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