Horizontal menu added but it does not look good on small screens.

I need to make sure that menu fits the column width of Less Framework.
I got the code of the menu from http://www.cssmenumaker.com/horizontal-css-menus

style.css

@@ -25,3 +25,20 @@ width:344px;
 float:left;
 padding-right:24px;
 }
+
+/* horizontal menu */
+.cssmenu ul {margin: 0; padding: 7px 6px 0; background: #7d7d7d url(overlay.png) repeat-x 0 -110px; line-height: 100%; border-radius: 1em; font: normal .8em/1.5em Arial, Helvetica, sans-serif; -webkit-border-radius: 5px; -moz-border-radius: 5px; border-radius: 5px; -webkit-box-shadow: 0 1px 3px rgba(0,0,0, .4); -moz-box-shadow: 0 1px 3px rgba(0,0,0, .4);}
+.cssmenu li {margin: 0 5px; padding: 0 0 8px; float: left; position: relative; list-style: none; }
+.cssmenu a {font-weight: bold; color: #e7e5e5; text-decoration: none; display: block; padding:  8px 20px; margin: 0; border-radius: 5px; -webkit-border-radius: 5px; -moz-border-radius: 5px;	 text-shadow: 0 1px 1px rgba(0,0,0, .3); }
+.cssmenu a:hover {background: #000; color: #fff;}
+.cssmenu .active a, 
+.cssmenu li:hover > a {background: #666 url(overlay.png) repeat-x 0 -40px; color: #444; border-top: solid 1px #f8f8f8; -webkit-box-shadow: 0 1px 1px rgba(0,0,0, .2); -moz-box-shadow: 0 1px 1px rgba(0,0,0, .2); box-shadow: 0 1px 1px rgba(0,0,0, .2); text-shadow: 0 1px 0 rgba(255,255,255, 1); }
+.cssmenu ul ul li:hover a,
+.cssmenu li:hover li a {background: none; border: none; color: #666; -webkit-box-shadow: none; -moz-box-shadow: none;}
+.cssmenu ul ul a:hover {background: #8f8f8f url(overlay.png) repeat-x 0 -100px !important; color: #fff !important; -webkit-border-radius: 5px; -moz-border-radius: 5px; border-radius: 5px; text-shadow: 0 1px 1px rgba(0,0,0, .1);}
+.cssmenu li:hover > ul {display: block;}
+.cssmenu ul ul {display: none; margin: 0; padding: 0; width: 185px; position: absolute; top: 40px; left: 0; background: #ddd url(overlay.png) repeat-x 0 0; border: solid 1px #b4b4b4; -webkit-border-radius: 5px; -moz-border-radius: 5px; border-radius: 5px; -webkit-box-shadow: 0 1px 3px rgba(0,0,0, .3); -moz-box-shadow: 0 1px 3px rgba(0,0,0, .3); box-shadow: 0 1px 3px rgba(0,0,0, .3);}
+.cssmenu ul ul li {float: none; margin: 0; padding: 3px; }
+.cssmenu ul ul a {font-weight: normal; text-shadow: 0 1px 0 #fff; }
+.cssmenu ul:after {content: '.'; display: block; clear: both; visibility: hidden; line-height: 0; height: 0;}
+* html .cssmenu  ul {height: 1%;}