TCPDF not render all CSS properties

I try to make a PDF writing CSS and HTML but my CSS doesn't appear in my PDF. The only thing considered is the font-size and font-color.

I give you the code (sorry, it's a little long...)

$config = sfTCPDFPluginConfigHandler::loadConfig('my_config');

    $doc_title    = "Fiche Logement";

    $html = <<<EOF
<style>
        .informations {
            padding: 10px;
            margin: 10px;
            border: 1px dotted black;}
        .informations table {
            margin-top: 10px;}
        #modif {
            margin: 20px;
            text-align: left;
            float: right;}
        #modif th {
            padding-left: 10px;}
        #modif td {
            padding-left: 10px;}
        #adresse {
            width: 307px;
            float: left;}
        #reservataire {
            width: 307px;
            float: right;}
        #intergen {
            width: 307px;
            float: right;}
        #infos {
            width: 290px;
            float: left;}
        #handicap {
            padding-bottom: 12px;
            width: 324px;
            float: right;}
        #charges {
            margin-bottom: 20px;
            width: 307px;
            float: left;}
        #loyer {
            width: 307px;
            float: right;}
        #commentaires {
            clear: both;}
        h2 {
            font-variant: small-caps;
            text-align: center;
            font-size: 19px;
            font-weight: bold;
            padding: 0px 0px 2px 5px;
            margin: 15px 0px 20px 0px;
            color: #000000;
            border-top: 1px dotted black;
            border-bottom: 1px dotted black;}

        h3 {
            width: 250px;
            font-variant: small-caps;
            font-size: 15px;
            font-weight: bold;
            padding: 0px 0px 0px 5px;
            margin: 0px;
            color: #225D6D;
            border-top: 1px dotted black;
            border-bottom: 1p