Nested Group Spacing/padding

[ehumphri]

I'm looking to create some nested containers (trying to diagram AWS VPC, AZ, subnets), and it would be nice to space so they don't all land on top of each other.

`diagram:
fill: "snow"
columns: 21
rows: 21
gridLines: false
gridPaddingInner: .4
groupPadding: .33
margins: {top: 20, right: 20, bottom: 50, left: 20 }
iconTextRatio: .33
title:
color: black
heightPercentage: 6
logoFill: none
stroke: lightgrey
type: "bar"
cisco: &cisco
color: black
fill: white
stroke: black
iconFamily: cisco
aws: &aws
color: black
fill: white
stroke: black
iconFamily: aws
cloud: &cloud
<<: *cisco
iconStroke: black
iconStrokeWidth: 2

instance: &instance {<<: *aws, icon: "cmpt_ec2_instance"}
router: &router {<<: *cisco, icon: "router"}
firewall: &firewall {<<: *cisco, icon: "firewall"}

icons:
firewall1: {<<: *firewall, x: 6, y: 17}
vma: {<<: *instance, x: 5, y: 15}
vmb: {<<: *firewall, x: 6, y: 15}
vmc: {<<: *instance, x: 7, y: 15}
proxy: {<<: *instance, x: 6, y: 13}
vm1: {<<: *instance, x: 4, y: 12}
vm2: {<<: *instance, x: 5, y: 12}
vm3: {<<: *instance, x: 6, y: 12}
vm4: {<<: *instance, x: 7, y: 12}
vm5: {<<: *instance, x: 8, y: 12}

connections:

vpc: &vpc
color: "black"
stroke: "black"
fill: "none"
strokeWidth: .5
textLocation: leftMiddle

az: &az
color: "black"
stroke: "black"
fill: "none"
strokeWidth: .5
strokeDashArray: [3,3]
textLocation: topRight

subnet: &subnet
color: "black"
stroke: "black"
fill: "none"
strokeWidth: .5
textLocation: topLeft

groups:
public sub 1: { <<: *subnet, name: public sub 1, members: [firewall1] }
private sub 1a: { <<: *subnet, name: private sub 1, members: [vma,vmb,vmc] }
private sub 1b: { <<: *subnet, name: private sub 2, members: [proxy,vm1,vm2,vm3,vm4,vm5] }
AZ1: { <<: *az, name: Availability Zone 1, members: [public sub 1,private sub 1a,private sub 1b] }

ProdVPC1: { <<: *vpc, name: Prod VPC 1, members: [AZ1] }
`

How can I get some spacing between ProdVPC1 and AZ1 groups? I've read through the docs, I've fiddled around a ton, I just can't seem to figure it out.