function currentOpac(id, opacEnd, millisec) { 
    //standard opacity is 100 
    var currentOpac = 100; 
     
    //if the element has an opacity set, get it 
    if(document.getElementById(id).style.opacity < 100) { 
        currentOpac = document.getElementById(id).style.opacity * 100; 
    } 

    //call for the function that changes the opacity 
    opacity(id, currentOpac, opacEnd, millisec) 
}