Hi guys, I'm looking to add a donation option to the cart to support a designated charity. This is much more likely to be taken-up in-cart than one placed on a block somewhere on the site. My idea was to give the customer the option to tick a box during checkout which lets them add an extra 5% of the value of their order which will then be donated and we will match their donation with an equal amount (totaling 10% of the value of their order to be donated). Hopefully this would work with the donations block so it doesn't require manual updating of donation amounts etc. I would like it to be added as a percentage of the sale as opposed to having a block somewhere else on the site as this allows me to match the donation out of a portion of the profits. Otherwise just having a donations block would allow people to make sporadic donations which may potentially l make it unsustainable for me to afford if I am to match it and there is a lull period as my product category is slow moving. Alternatively I thought to give people a "save or donate" option, where with every order they receive a pair of codes that gives them a choice. One which gives them a 5% discount on their next purchase and the other which adds a 5% donation to their next purchase which we then match. I thought this might be able to be done with a negative value discount code, or via the 'tax' tab, but unfortunately neither option seems to work. I know there is a plugin out there that allows dollar-value donations to be made in cart, but when you're selling products this then adds sales tax which is an issue and again I'd prefer percentages as opposed to dollar values. Does anyone have any idea how to implement this, maybe via another plugin that you know of, or maybe Squarespace already has this and I'm missing it somehow? Thank you!