ul#top-menu.menu li { font-size: 20px; /* values in rem, em or px */ }
I’ve set colors to black and white in above pieces of code. You can set the color you want, with its rgb, rgba, hexadecimal or name.
.navigation-top, .main-navigation ul { background: black !important; }
.navigation-top a, .menu-toggle { color: white !important; }
.navigation-top { background-image: url("https://mydomain.com/wp-content/uploads/2017/07/picture.jpg") !important; } .main-navigation ul { background: transparent !important; }