Unable to position image in page footer?

Hi all,

I have placed an image (purple color) in the page footer.

When i try to use the following code to align in center it doesn't change.If i use flexbox within panel it gets aligned to center but i dont want the grey shade panel backgound.I tried to apply via css too but failed.Please help me.

<footer >
  <Toolbar>
        <content >
          <FlexBox alignItems="Center" justifyContent="Center">
          <items>
            <Image src="images/logobar.png" height="54px">
            </Image>
          </items>
          </FlexBox>
        </content>
     </Toolbar>
  </footer>