<size 100><sym></sym></size> <size 50>Workperiod</size>
[=('{SETTING:ISCURRENTWORKPERIODOPEN}'=='TRUE' ? '<color #FF9BDD59><bold><size 50>OPEN</size></bold></color>' : '<block 5,5,5,5 Red><italic>CLOSED</italic></block>')]
Notice the line that is responsible for setting the background color:
<block 5,5,5,5 Red><italic>CLOSED</italic></block>
You can also specify color in Hex:
<block 5,5,5,5 #FF0000><italic>CLOSED</italic></block>
More flexibility to set transparency level in Hex with first 2 characters:
<block 5,5,5,5 #33FF0000><italic>CLOSED</italic></block>
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