You may not be able to do this using pure CSS. But, a little javascript can do it nicely.
A crude way to do it –
var sel = document.getElementById('select_id');
sel.addEventListener('click', function(el){
var options = this.children;
for(var i=0; i < this.childElementCount; i++){
options[i].style.color="white";
}
var selected = this.children[this.selectedIndex];
selected.style.color="red";
}, false);