Put archieves below nav menu

Try this in child theme’s stylesheet.

/*--------------------------------*\
	Move up archive widget
\*--------------------------------*/

#page { position: relative; }

#archives-3 {
	position: absolute;
	top: 280px; left: 250px;
	z-index: 200;
	width: 200px;
	text-align: center;
}

#main #primary { margin-top: 48px; }