title: How to add shadow in @react-navigation/bottom-tabs?
body: <p>i am trying to apply shadow on react-native bottom tab but i am unable to do that,
  how can we add shadow on react native bottom tab?</p>
  <p>my tab bar style.</p>
  <pre><code>   tabBarOptions={{  
        style: {
          // flex:1,
          position: 'absolute',
          backgroundColor:
          themeColorcontext.themeColor == 'light' ? '#fff' : '#222',
          borderTopLeftRadius: vpWidth*0.085,
          borderTopRightRadius: vpWidth*0.085,
          height: vpHeight*0.15,
          shadowColor: themeColorcontext.themeColor == 'light' ? 'rgba(0,0,0,0.5)' : 'rgba(255,255,255,0.5)',
          shadowOffset: { width: 0, height: 6 },
          shadowOpacity: 1,
          shadowRadius: 6,  
          elevation: 10,
          // flexWrap:'wrap', 
          borderTopColor:themeColorcontext.themeColor == 'light' ? '#fff' : '#222',
          borderTopWidth:1,
          borderWidth:1,
          borderColor:themeColorcontext.themeColor == 'light' ? '#fff' : '#222',
          // width:20
        },
      }}
  </code></pre>