User theme has 4 variations (Green,yellow and blue.You can always add more with css).

$('#start').on('click',function(){
    $.amaran({
        'theme'     :'user blue',
        'content'   :{
            img:'http://api.randomuser.me/0.2/portraits/men/36.jpg',
            user:'John Walker',
            message:'Lorem ipsum dolor sit amet, consectetur adipisicing elit. Cupiditate, ducimus?'
        },
        'position'  :'bottom right',
        'outEffect' :'slideBottom'
    });
});