unable to center image on slideshow

I have 3 images on flexSlider. I already check “align center” box in Advanced setting. but all images are not aligned properly

Here is my setting:
Width: 1024 px
Height: 340 px
Advanced setting:
Image crop: Smart-crop
Carousel margin: 200 px
Slide delay: 3000 ms
Animation speed: 600 ms
Slide direction: horizontal
Easing: linear
checked boxes:
> 100% width
> Center align
> auto play
> Carousel mode
> hover pause

The page I need help with: [log in to see the link]