Hi,

You can add css code here http://www.awesomescreenshot.com/image/431375/60a65bbd73398f66ec983fe267a49737

@media (min-width: 991px) and (max-width: 1199px){
    h1{ font-size: 40px!important; }
    .header-handyman ul li { font-size: 20px!important; }
}

@media (min-width: 768px) and (max-width: 991px){
    h1{ font-size: 30px!important; }
    .header-handyman ul li { font-size: 20px!important; }
}

@media (max-width: 767px){
    h1 { font-size: 20px!important; }
    .header-handyman ul li { font-size: 20px!important; }

}

You can change 40,30,20 to your size.