With the help of JavaScript, please try this:
Step1:- In my case, there are three HyperLink(a1,a2,a3)in my .aspx page. Suppose, we want to set the color (a1:-Red, a2:- Green, a3:-Blue) on the click of the button (onclick).
<a id="a1" onclick="showred()">Red</a><br />
<a id="a2" onclick="showgreen()">Green</a><br />
<a id="a3" onclick="showblue()">Blue</a>
Step2:- In the head part, we specify the JavaScript function:-
function showred()
{
document.getElementById('a1').style.color='Red';
}
function showgreen()
{
document.getElementById('a2').style.color='Green';
}
function showblue()
{
document.getElementById('a3').style.color='Blue';
}