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My company has ruled out QuickBooks because it falls short as a subscription billing platform when the rules approach telecom complexity - prorate first month charges, prorate last month credits, roll up subaccount charges/credits in an N-level customer hierarchy, bill the customer once per the product's/service's cycle (week, month, ...

I am considering Method CRM.  I've searched the forum for information about CSS templates, but I've not been able to locate information on whether I can bring my own CSS, modify the standard templates, etc. How much control over the CSS templates do I have?