Add Logo to navigation and change size of slider

I was wondering how I would go about removing the white space about the navigation (indicated by the red arrows)

I would also like to place my logo within the navigation bar (indicated by the red arrows)

Lastly, I was wondering if it is possible to reduce the size of the slider window. It is a bit large for the images. Wanted to shrink it a bit on both sides of the margin to make it more square than rectangle. (indicated by the red arrows)

http://lisanamataphotography.com/wp-content/uploads/2017/08/Shrink_Slider.png

Any help with these and where I can generally change theses like these (style.css, etc.) is helpful. I’m always willing to learn 😛

Thanks again!