Keep interpolation in var CSS function #163

Job	Run time
Static analysis	20s
Dart tests \| Dart stable \| ubuntu-latest	1m 9s
Node tests \| Dart stable \| Node 18 \| ubuntu-latest	1m 5s
Dart tests \| Dart stable \| windows-latest	1m 45s
Node tests \| Dart stable \| Node 18 \| windows-latest	2m 16s
Dart tests \| Dart stable \| macos-latest	1m 57s
Node tests \| Dart stable \| Node 18 \| macos-latest	1m 30s
Node tests \| Dart stable \| Node 16 \| ubuntu-latest	1m 5s
Node tests \| Dart stable \| Node 14 \| ubuntu-latest	1m 5s
Node tests \| Dart dev \| Node \| ubuntu-latest	1m 1s
Sanity checks	0s
Deploy npm	0s
Deploy Github: Linux	0s
Deploy Homebrew	0s
Deploy Pub	0s
Deploy Github: Mac OS	0s
Deploy Github: Windows	0s
	13m 13s

Provide feedback