Hello,

1-menu’s background color:
You can change the background color and font color in Specular > Header Options > Dropdown Options & Mobile Menu > Dropdown Background Color / Dropdown typography.

2-Link color:

.menu-small ul.menu > li > a {
    color: #fff !important;
}

3-Link hover color:

.menu-small ul.menu > li > a:hover {
    color: #fff !important;
}

4-Visited link color:

.menu-small ul.menu > li > a:visited {
    color: #fff !important;
}

Change the color to your wish.

Best regards!