The styles on my links doesn't work on the Gmail email client. I use both inline and in the body tag styles, but it doesn't change at all. Here is the code I use:

.linkCell a,  .linkCell a:link, .linkCell a:hover, .linkCell a:visited {
            text-align: center !important;
            display: block !important;
            line-height: 40px !important;
            color: #fefefe !important;
            font-weight: bold !important;
            text-transform: uppercase !important;
            font-size: 14px !important;
            font-family: 'Trebuchet MS', Helvetica, sans-serif !important;
            text-decoration: none !important;
}