nav{
}
nav ul{
    background: green;
    padding: 0px;
    margin: 0px;
    list-style: none;
}
nav ul li{
    list-style: none;
    float: left;
    font-size: 12px;
    display:inline;
    
}

nav ul li a {
    padding: 10px 14px 10px 14px;
    color: darkgrey;
    font-family: "Tahoma", "Arial", "Verdana", "Lucida Grande CE", "Helvetica CE";
    text-decoration:none;
    display:block;
    font-weight: 600;
    
}
nav ul li a:hover {
    color:white;
    
}
.active a{
    padding: 0px 14px 10px 14px;
    display: block;
    margin: 0px;
    padding: 0px;
    color: white;
    font-weight: 600;
    border-color: white  transparent transparent transparent ; /* pak upravit zobacek*/
    border-style: solid;
    border-width: 10px 20px 10px 20px;
    
    
}