This is my stylesheet for caption:
.wp-caption {
border: 1px solid #DDDDDD;
text-align: center;
background-color: #EEEEEE;
padding: 4px 0px 5px 0px;
-moz-border-radius: 3px;
-khtml-border-radius: 3px;
-webkit-border-radius: 3px;
border-radius: 3px;
}
.wp-caption img {
margin: 0px 0px 5px 0px;
padding: 0px;
border: 0px;
}
.wp-caption p.wp-caption-text {
margin: 0px;
padding: 0px 0px 0px 0px;
font-size: 11px;
font-weight: normal;
line-height: 12px;
}