here is the complete code of CSS for images on my mx4 theme:
/********* Begin Images *********/
img.wp-smiley {border:none;}
/*img.wp-smiley {
border:none;
margin:0;
padding:0;
}*/
.entry img {
background-color: #ffffff;
border: 1px solid #dddddd;
/*-moz-border-radius:5px;*/
padding: 4px;
max-width: 334px;
}
.entrytext img {
background-color: #ffffff;
border: 1px solid #dddddd;
/*-moz-border-radius:5px;*/
padding: 4px;
max-width: 392px;
}
.img {
background-color: #ffffff;
border: 1px solid #dddddd;
/*-moz-border-radius:5px;*/
padding: 4px;
}
.imgleft {
float: left;
margin-bottom: 6px;
background-color: #ffffff;
border: 1px solid #dddddd;
/*-moz-border-radius:5px;*/
padding: 4px;
}
.imgright {
float: right;
margin-bottom: 6px;
background-color: #ffffff;
border: 1px solid #dddddd;
/*-moz-border-radius:5px;*/
padding: 4px;
}
p img {
max-width: 100%;
}
img.centered {
background-color: #ffffff;
border: 1px solid #dddddd;
/*-moz-border-radius:5px;*/
padding: 4px;
display: block;
margin-left: auto;
margin-right: auto;
}
img.alignright {
background-color: #ffffff;
border: 1px solid #dddddd;
/*-moz-border-radius:5px;*/
padding: 4px;
padding: 4px;
margin: 0 0 2px 7px;
display: inline;
}
img.alignleft {
background-color: #ffffff;
border: 1px solid #dddddd;
/*-moz-border-radius:5px;*/
padding: 4px;
padding: 4px;
margin: 0 7px 2px 0;
display: inline;
}
.gravatar {
float: left;
margin: 2px 10px 6px 0px;
background-color: #ffffff;
border: 1px solid #dddddd;
padding: 2px;
}
/********* End Images *********/