Stacking widgets in the header

Hi folks – hoping you can help me fix some herder issues on http://www.jlbodyconditioning.com

I have two widgets in the header – the vantage social media (love this widget, btw) and just a text widget for the contact details, but, although I got them to align right where I want them using the code below, I have no idea what to add or change in the code to get the two widgets to display stacked rather than next to one another. Inserting “display: inline;” doesn’t seem to have an effect.

header#masthead hgroup #header-sidebar aside.widget {
  	position: relative;

	float: right;
	margin-bottom: 15px;
	margin-right: 25px;
}

Thanks!
H