Solpart Menu Effect
  EffectsShadowColor Color of the shadow menueffectsshadowcolor  
  EffectsTransition Determines which transition to display menueffectsmenutransition Supports:  None, AlphaFade, AlphaFadeBottomRight, Barn, Blinds, Checkerboard, ConstantWave, Fade, GradientWipe, Inset, Iris, RadialWipe, Random, RandomBars, Slide, Spiral, Stretch, Strips, Wave, Wheel, Zigzag
  EffectsDuration Number of seconds the transition will take menueffectsmenutransitionlength  
  EffectsShadowDirection Determines which direction the shadow will fall menueffectsshadowdirection Supports: None, Top, Upper Right, Right, Lower Right, Bottom, Lower Left, Left, Upper Left
  EffectsShadowStrength Determines how opaque the shadow is menueffectsshadowstrength  
  StyleMenuEffects IE only property for SubMenu styles and transitions menueffectsstyle  

Good article from Skinning Toolkit

Main Menu - SolPart Menu Styling Classes

Follow the links below or from the bottom of the menu to view a demonstration of the SolPart Menu classes from the default.css file that comes as standard with DotNetNuke.

If you need to learn how to style an element of a DotNetNuke skin, enter the element into the search box at the top left, for instance, breadcrumbs.