An OmniStudio Developer needs to ensure that a FlexCard displays correctly on small mobile screens...

Padding is the correct property because padding controls the internal space between an element’s content and its border. In this scenario, the developer wants to reduce horizontal space inside the FlexCard on small mobile screens, so the relevant adjustment is left and right padding. Margin would control space outside the element, between the element and surrounding elements, not inside the element. Border controls the line or visual boundary around the element. “Spacing” is too generic and is not the precise CSS box-model property being tested. Salesforce FlexCard styling documentation explains that FlexCard elements can be styled through the Style panel and CSS-related properties, and the CSS box model distinction makes padding the correct answer for internal spacing.

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