Flyout Quick Launch Menu

Find:
 <SharePoint:AspMenu id=”V4QuickLaunchMenu”
 V4QuickLaunchMenu
Set StaticDisplayLevels and MaximumDynamicDisplayLevels to 1.
Open _styles\corev4.css
find the below section and add the background color so that it's not transparent.
.s4-ql ul.root ul > li > a{
/* ADD THIS */
background-color:white;