Why is the Bartik theme right sidebar positioned over my content?

Hey, I made a very simple subtheme of Bartik. I copied over the layout.css file to my subtheme to tweak the position and size of the right sidebar, but now the sidebar has shifted left into my content.

I even tried deleting my new css file and removed the line stylesheets[all][] = css/layout.css from the .info file of the subtheme, so my website should now by default use the layout.css file from Bartik right? But it doesn't. My website is www.howtogetintomedicine.com if you want to see the problem.

The section of code in bold below is what I edited. Anyone have any idea why this is happening?

/* ---------- Basic Layout Styles ----------- */

html,
body,
#page {
height: 100%;
}
#page-wrapper {
min-height: 100%;
min-width: 960px;
}
#header div.section,
#featured div.section,
#messages div.section,
#main,
#triptych,
#footer-columns,
#footer {
width: 960px;
margin-left: auto;
margin-right: auto;
}
#header div.section {
position: relative;
}
.region-header {
float: right; /* LTR */
margin: 0 5px 10px;
}
.with-secondary-menu .region-header {
margin-top: 3em;
}
.without-secondary-menu .region-header {
margin-top: 15px;
}
#secondary-menu {
position: absolute;
right: 0; /* LTR */
top: 0;
width: 480px;
}
#content,
#sidebar-first,
#sidebar-second,
.region-triptych-first,
.region-triptych-middle,
.region-triptych-last,
.region-footer-firstcolumn,
.region-footer-secondcolumn,
.region-footer-thirdcolumn,
.region-footer-fourthcolumn {
display: inline;
float: left; /* LTR */
position: relative;
}
.one-sidebar #content {
width: 720px;
}
.two-sidebars #content {
width: 480px;
}
.no-sidebars #content {
width: 960px;
float: none;
}
#sidebar-first,
#sidebar-second {
width: 240px;

}
#main-wrapper {
min-height: 300px;
}
#content .section,
.sidebar .section {
padding: 0 15px;
}
#breadcrumb {
margin: 0 15px;
}
.region-triptych-first,
.region-triptych-middle,
.region-triptych-last {
margin: 20px 20px 30px;
width: 280px;
}
#footer-wrapper {
padding: 35px 5px 30px;
}
.region-footer-firstcolumn,
.region-footer-secondcolumn,
.region-footer-thirdcolumn,
.region-footer-fourthcolumn {
padding: 0 10px;
width: 220px;
}
#footer {
width: 940px;
min-width: 920px;
}