I have an easy question for which I hope you could help:
Feed Git's answer is perfect, here's another example with multiple attributes. Just separate with commas:
:style="[printing ? {'margin' : '0px 0px 20px 0px', 'min-height': '830px', 'box- shadow': 'none', 'border': 'none'} : {'margin': '0px 0px 20px 0px', 'min-height': '830px'}]
The form follows (for someone like me who's new at this):
:style="[boolVariable ? { true } : { false }]