@Dottie: I see that you have changed our default slider to meta slider that is why there was gap issues. You can add the padding bottom by adding in the following CSS in “Appearance => Theme Options => Custom CSS” box.
.metaslider { padding-bottom: 30px; }
To change the color of the background behind my logo, you can go to “Appearance => Theme Options => Color Option” and pick the color to desire color or just add in color code in “Header Background Color”
I don’t recommend font size in responsive design site as it will effect in the mobile devices as well. So, to change the font size either you change it for all devices or write specific css only for large screens.
/* For Sidebar Widget Content */
#secondary .widget, .widget a { color: #000; }
/* For Sidebar Widget Title */
#secondary .widget .widget-title, #secondary .widget .widget-title a { color: #000; }