Featured image and comment box

Hi! Firstly, love the theme, it looks great! But I just had a few things I'd like help with (apologies if they're really dumb - I'm totally new to this). 1. When I set a featured image for my posts and enable the featured header, the featured image appears in the header AND just above the title of the post. I’d like it to just appear in the header – is that possible somehow? Example: http://www.lostinthemidlands.com/2016/10/10/skydiving-in-queenstown/ 2. I’d like to change the colour scheme of the comment box on my posts to match the rest of my site but can’t find the colour options to change it? Example: http://www.lostinthemidlands.com/2014/02/23/libreria-acqua-alta/ 3. The featured image slider on the homepage is a little different on my mobile site compared to desktop. On my computer the image that is currently displaying turns to a blank white box on the ribbon below (that shows all the featured images), whilst on my mobile it just displays the normal image and not a white box. I’d love it if my desktop version could look the same as the mobile one. Thank you so much for your help! Justine Homepage: http://www.lostinthemidlands.com