How do you expect anybody to properly help you without a link?
Based on the preview of the Photolistic theme:
Open the style.css file in WP dashboard-Appearance-Editor
Find line 431:
#access .menu-header, div.menu {
border-bottom-color: #aaa;
border-bottom-style: dashed;
border-bottom-width: 1px;
border-top-color: #aaa;
border-top-style: dashed;
border-top-width: 1px;
font-size: 13px;
margin-bottom: 0;
margin-left: auto;
margin-right: auto;
margin-top: 0;
width: 60%;
}
Increase the percentage value of “width” selector.
If this is still not enough, find line 451:
#access a {
-moz-text-decoration-color: -moz-use-text-color;
-moz-text-decoration-line: none;
-moz-text-decoration-style: solid;
color: #999;
display: inline;
font-size: 12px;
font-weight: 900;
letter-spacing: -1px;
line-height: 38px;
padding-bottom: 0;
padding-left: 10px;
padding-right: 10px;
padding-top: 0;
}
Decrease the values of “padding-right” and/or “padding-left”. You can also decrease the values of “font-weigth” and/or “font-size”, although the readibility will worsen. Shortening the link titles can help, but you probably already knew this.