Site para escolher a cor: https://htmlcolorcodes.com/
Para alterar a cor dos icones:
Branco = brightness(100).
Preto = brightness(0).
Script
.head-primary, .nav-secondary .nav-account, .desktop-list-subitems {
background-color: #0e1b4d;
}
.nav-list-link, .transition-soft {
color: white !important;
}
.head-primary .utilities-item svg, svg.icon-inline.icon-md {
filter: brightness(100) saturate(100%)
}
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