:root {
    --menu-search-placeholder-color: #d1d1d1;
    --menu-search-placeholder-weight: lighter;
}

.et_pb_menu__search input::placeholder,
.et_pb_fullwidth_menu .et_pb_menu__search-input,
.et_pb_menu .et_pb_menu__search-input {
    color: var(--menu-search-placeholder-color);
    font-weight: var(--menu-search-placeholder-weight);
}