Use css-definition for getContext-function?

Question

Is it possible to define a stylesheet for functions in js?

<canvas id="canv" onclick=loadContext() />

#canv {
    width: 500px;
    height: 200px;
    background-color: darkblue; 
}


function loadContext ()
{
    var context = canv.getContext("2d");
    /* use css-definition here? */
    context.strokeStyle = "white";  
    context.beginPath();
    context.moveTo(0, 0);
    context.lineTo(300, 150);
    context.stroke();   
}

I'd like to use a definition in css instead of "white".

JSFiddle

Thanks for your help. Joe