:first-child {
//styles here
}
:nth-child(1) { //the benefit of this is you can do it for 2nd, 3rd etc...
//styles here
}
/*CSS First - forth child*/
:first-child {}
:nth-child(2){}
:nth-child(3){}
:nth-child(4){}
:nth-child(1){
/* css code here */
}
li:nth-child(-n+5) {
color: green;
}
selector:first-child{
//style
}