Two Qs: 1) Tagline alignment; 2) Menu buttons

Hey there.

I hope you’re well! 🙂

1. You could add some margin on the left so that the H3 tag shifts over:

#logo h3{
	margin-left: 10px;
}

Change the 10 part up or down to whatever works with your site.

2. For the menu you could use some CSS like this:

#menu .current_page_item{
	background-color:#000;
}

You would change the colour to one of your choosing, here is a helpful site for hex codes:

http://www.color-hex.com/

There is a chance that the theme has a CSS field in the options, if not then you can make a child theme:

http://codex.wordpress.org/Child_Themes
http://premium.wpmudev.org/blog/create-wordpress-child-theme/

Or you can instead use a plugin if you like:

http://wordpress.org/plugins/custom-css-manager-plugin/screenshots/

http://wordpress.org/plugins/my-custom-css/screenshots/

http://wordpress.org/plugins/pc-custom-css/

http://wordpress.org/plugins/imporved-simpler-css/screenshots/

Have a fantastic day! 🙂