html ul li e.g. example eg sample

to css page header

<ul id=:"nav">
<li><a href="home.html">home</a>,/li>
<li><a href="about.html">About Us</a>,/li>
<li><a href="product.html">Our Product</a>,/li>
</ul>

no . style
ul#nav,ul#nav li{
list-style:none;
margin:0;
padding:0;
}

on a line style
ul#nav,ul#nav li{
float:left;
list-style:none;
margin:0;
padding:0;
}

Button style 

ul#nav{
font-family:aaaaa;
font-size:.82em;
background-color:#DDD;
}

ul#nav li a{
border: 1px solid #000;
display:block;
float:left;
padding: 3px;
}