You should be able to write a css selector for the select element within the div with a certain class. So, say you give the dropdown div the class “.dropdown-empty-message” or something, you should be able to use something like:
.dropdown-empty-message {
select.form-control {
option{
&:first-child{
<your styling here>
}
}
}
}
This specifically targets the first (empty) option of your drop-down.