CSS not showing up on Windows browsers

I’m a CSS newbie and am learning as I go along. I’ve installed Rubric for now, but for some reason the CSS is not loading on PCs. I’m not sure whether there is a problem with the CSS, or my settings.
This is the code:
—-
/* Whole page
——————————————– */
body {
background-image: url(“images/rubric/gradient.gif”);
background-attachment: fixed;
background-position: bottom;
background-repeat: repeat-x;
}
#content {
margin-right: 20em;
margin-left: 40px;
background-color: #fff;
padding: 0.5em;
margin-top: 160px;
border: 1px #eee solid;
}
/* Image from sxc.hu (https://www.sxc.hu/browse.phtml?f=view&id=16710)
Thanks bradleym! */
#header {
position: absolute;
top: 40px;
left: 0px;
background-image: url(“images/rubric/pen-sm.jpg”);
background-position: top right;
background-repeat: no-repeat;
width:80%;
margin: 0;
height: 150px;
padding-left: 45px;
font-family: Georgia;
font-weight: normal;
font-size: 3em;
}
/* Content & menu
——————————————– */
#menu {
width: 14em;
position: absolute;
float: right;
top: 200px;
right: 5em;
font-size: 90%;
}
* html #menu { /* make IE put it in the right place */
right: 5em;
}
#menu ul {
margin-top: 0;
padding-left: 0;
margin-left: 0;
list-style: none;
color: #B54141;
/*text-indent: 1000em;*/
}
#menu a:link, #menu a:visited {
color: black;
border: none;
}
#menu ul ul {
margin-left: 0;
list-style: disc;
list-style-position: inside;
padding-left: 0.5em;
text-indent: 0;
color: black;
}
#menu form{
margin: 0;
}
#menu form br {
display:none;
}
input {
width: 6em;
font-family: Verdana, Tahoma, Arial, sans-serif;
}
/* Post
——————————————– */
#content h2 {
font-size: 0.9em;
color: #666;
margin-bottom: 0;
margin-top: 0;
}
h3 {
font-size: 1.5em;
font-weight: normal;
margin-bottom: 0.33em;
}
.storytitle {
margin-top: 0.25em;
}
.post-categories {
display: inline;
margin: 0;
padding: 0;
}
.post-categories li {
display: inline;
margin-left: 0 3px 0 0;
padding: 0;
}
.post .meta {
font-size: 0.85em;
color: #666;
}
.post .meta * {
margin-top: 0;
}
.post .feedback {
margin-bottom: 3em;
border-bottom: 1px solid #ccc;
padding-bottom: 1px;
}
/* Credit
——————————————– */
p.credit {
margin-right: 20em;
margin-left: 40px;
padding: 0.5em;
font-size: 90%;
}
p.credit a:visited, p.credit a:link {
border: none;
}
/* Basic typography
——————————————– */
body {
font-family: Verdana, Tahoma, Arial, sans-serif;
font-size: 80%;
}
p, td, th, li {
font-size: 1em;
line-height: 1.65em;
}
a:link, a:visited {
text-decoration: none;
color: #B54141;
border: 1px solid white;
}
a:hover {
background-color: #eee;
border: 1px solid #ccc;
}
/* Temporary & testing
——————————————– */
/* Backup of coloured menu headings
#menu ul {
margin-top: 0;
padding-left: 0;
margin-left: 0;
list-style: none;
background-color: #B54141;
color: #fff;
padding: 1px;
}
#menu ul ul {
background-color: white;
margin-left: 0;
list-style: disc;
list-style-position: inside;
padding-left: 0.5em;
}
#menu ul ul * {
background-color: white;
color: #000;
width: 100%;
}
#menu table, #menu form, #menu caption {
background-color: #fff;
color: black;
width: 100%;
}
*/
—
If anyone can offer any suggestions and advice, I would be most grateful.
Thanks in advance.