You could use the :first-child and :last-child pseudo-selectors
:
tr td:first-child{
color:red;
}
tr td:last-child {
color:green
}
Or you can use other way like
// To first child
tr td:nth-child(1){
color:red;
}
// To last child
tr td:nth-last-child(1){
color:green;
}
Both way are perfectly working