DIV list links refuse to touch - html

Question

My links are not Start Class and Center class for my website I am building. I have gone over this several times and can not see what I have done wrong. Can someone please assist me with this?
My html
<DIV class="outline">
<DIV class="navigation">
<ul>
<li class="orange start">Home</li>
<li class="orange center">Forum</li>
</ul>
</DIV>
</DIV>
My Css class
/*Start Links*/
a:link {
color: #FFFFFF;
text-decoration: none;
margin: 0;
}
a:visited {
color: #FFFFFF;
text-decoration: none;
}
a:hover {
color: #FFFFFF;
text-decoration: none;
}
a:active {
color: #FFFFFF;
text-decoration: none;
}
.navigation ul li {
margin: 0px auto;
display: inline-block;
}
/*End Links*/
/*Start Button*/
.start {
display: inline-block;
outline: none;
cursor: pointer;
text-align: center;
text-decoration: none;
font: 14px/100% Arial, Helvetica, sans-serif;
padding: .5em 2em .55em;
text-shadow: 0 1px 1px rgba(0,0,0,.3);
-webkit-border-radius: .5em 0 0 .5em;
-moz-border-radius: .5em 0 0 .5em;
border-radius: .5em 0 0 .5em;
-webkit-box-shadow: 0 1px 2px rgba(0,0,0,.2);
-moz-box-shadow: 0 1px 2px rgba(0,0,0,.2);
box-shadow: 0 1px 2pxrgba(0,0,0,.2);
margin: 0px;
}
.center {
display: inline-block;
outline: none;
cursor: pointer;
text-align: center;
text-decoration: none;
font: 14px/100% Arial, Helvetica, sans-serif;
padding: .5em 2em .55em;
text-shadow: 0 1px 1px rgba(0,0,0,.3);
-webkit-border-radius: 0;
-moz-border-radius: 0;
border-radius: 0;
-webkit-box-shadow: 0 1px 2px rgba(0,0,0,.2);
-moz-box-shadow: 0 1px 2px rgba(0,0,0,.2);
box-shadow: 0 1px 2pxrgba(0,0,0,.2);
margin: 0;
}
.button {
display: inline-block;
outline: none;
cursor: pointer;
text-align: center;
text-decoration: none;
font: 14px/100% Arial, Helvetica, sans-serif;
padding: .5em 2em .55em;
text-shadow: 0 1px 1px rgba(0,0,0,.3);
-webkit-border-radius: .5em;
-moz-border-radius: .5em;
border-radius: .5em;
-webkit-box-shadow: 0 1px 2px rgba(0,0,0,.2);
-moz-box-shadow: 0 1px 2px rgba(0,0,0,.2);
box-shadow: 0 1px 2pxrgba(0,0,0,.2);
}
.button:hover {
text-decoration: none;
}
.button:active {
position: relative;
top: 1px;
}
.orange {
color: #fef4e9;
border: solid 1px #da7c0c;
background: #f78d1d;
background: -webkit-gradient(linear, left top, left bottom, from(#faa51a), to(#f47a20));
background: -moz-linear-gradient(top, #faa51a, #f47a20);
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#faa51a', endColorstr='#f47a20');
}
.orange:hover {
background: #f47c20;
background: -webkit-gradient(linear, left top, left bottom, from(#f88e11), to(#f06015));
background: -moz-linear-gradient(top, #f88e11, #f06015);
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#f88e11', endColorstr='#f06015');
}
.orange:active {
color: #fcd3a5;
background: -webkit-gradient(linear, left top, left bottom, from(#f47a20), to(#faa51a));
background: -moz-linear-gradient(top, #f47a20, #faa51a);
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#f47a20', endColorstr='#faa51a');
}
/*End Button*/
/*Start Website*/
body {
background-color: #393939;
color: #FFFFFF;
padding: 0;
margin: 0;
}
.header {
display: inline-block;
width: 100%;
text-align: left;
border:solid 2px red;
}
.circle {
float: left;
width: 100px;
height:100px;
display: inline-block;
background: #FF5A09;
-webkit-border-radius: 50%;
-moz-border-radius: 50%;
border-radius: 50%;
}
.header h1.first {
margin-top: 30px;
margin-left: -92px;
margin-right: 5px;
display: inline-block;
color: #FFFFFF;
}
.header h1.last {
display: inline;
color: #FF5A09;
}
.header .right {
display: block;
height: auto;
float: right;
padding: 10px 10px 10px 10px;
border-left: solid 2px red;
}
.navigation {
margin: 0 auto;
display: inline-block;
width: 100%;
text-align: center;
}
.outline {
display: block;
margin: 0 auto;
width: 980px;
border: solid 2px red;
}
.content {
display: inline-block;
width: 60%;
border: solid 2px red;
margin: 0 auto;
}
.footer {
display: block;
width: 100%;
border: solid 2px red;
padding: 10px 0 10px 0;
text-align: center;
}
/*End Website*/
/*Start slider*/
/*End slider*/

Answer 1

It is because the whitespace between the <li> elements is significant. If you remove all whitespace, the elements will be right next to each other. Either you just do this:
<li class="orange start">Home</li><li class="orange center">Forum</li>
Or, if you want to keep the line breaks in code, which I usually think is a good thing, you can insert an HTML comment like this:
<li class="orange start">Home</li><!--
--><li class="orange center">Forum</li>
It's a matter of taste, but I tend to favor the latter because I find it more readable.