I would like to move my menu to the top left on the desktop view as it is on the mobile view and reduce the spacing of the header and slideshow so there is not so much white space. My site is www.onestylishpet.com
I have gone through your site your logo size is very big, so its looking like that, after removing padding margin
it will look like this
for more spacing you want to reduce you have change the logo size !