Firefox is using MS Gothic by default. But Meiryo looks much better (and it is by default in Chrome).
@@ -11,7 +11,7 @@ body {
background: #fff;
color: #000;
font-size: 14px;
- font-family: Tahoma, Arial, Verdana, sans-serif, Lucida Sans;
+ font-family: Tahoma, Arial, Verdana, Meiryo, "MS Gothic", sans-serif, Lucida Sans;
line-height: 1.5em;
text-align: center;
}