Need help multiplying cells together across multiple columns, then getting a total

Hi!
I'm trying to set up a sheet to help me with pricing my jewelry and I would so appreciate any pointers in the right direction.

I'm attaching a sample sheet, and it show where I got so far (the row with the total of 6.92) and lower down shows what I'm trying to have happen, which is for the value in each yellow cell (highlighted for this example, but I'm trying for a formula that scans the whole row for values greater than zero in any column) to be multiplied by the value in each purple cell, and then those figures totaled in the green cell.

The other thing I've already run into is that when I try to either pull the formula down or copy/paste it lower in the sheet, both sets of cell indicators (like B5, etc, I don't know what they're called) change accordingly (which is to be expected) but I'm wondering if there's a way to "lock" one set (the yellow cells, which will always be the reference) and have the indicators for the purple cells move lower and lower as we pull down/copy lower in the sheet. Hope that makes sense!

Thanks so much for any wisdom

Kindest regards,
Julia

That's exactly what I was looking for, thank you so much! It solves both problems, and really cleanly The absolute values part is great to understand. Thank you for the kind help!