Hello guys, i have a simple css file called Titulos.css who contain this:

h1 {    font: 50px Tahoma, Helvetica, Arial, Sans-Serif; text-align: center; color: #111; text-shadow: 0px 2px 3px #555;    }
h2 {    font: 14px Tahoma, Helvetica, Arial, Sans-Serif; text-align: center; color: #CCC; text-shadow: 0px 1px 2px #555;    }
h3 {    font: 10px Tahoma, Helvetica, Arial, Sans-Serif; text-align: center; color: #CCC;   }
b1 {    font: 16px Tahoma, Helvetica, Arial, Sans-Serif; color: #DDD;   }
b2 {    font: 10px Tahoma, Helvetica, Arial, Sans-Serif; color: #F9F7ED;    }
.caja {  width: 690px; height: 40px; background-color: transparent; border: 0px solid #000000; font-size:x-large; color: #222; font-family: 'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande', 'Lucida Sans', Arial, sans-serif; font-weight: bold;" size="299";  }
.style1 {   text-align: right; }

And a page who call this file like:

<link rel="stylesheet" type="text/css" href="LIB/titulos.css" />

Later in this page im trying to use some of the styles like:

<div id="todo" align="center" >
    <div id="cabeza" style="width:850px;height:100px">
    </div>
    <div id="contenido" style="width:850px;height:420px;background-image: url(IMG/cuadro.png)" >
        <div id="titulo" style="width:765px;height:75px;padding-top: 18px;margin: auto;text-align: left;">
            <b1>Bienvenido <b><?php echo($username); ?></b></b1><br>
            <?php $check = mysql_query("SELECT * FROM sms WHERE ref = '".$username."' ORDER BY fecha DESC LIMIT 0, 1") or die(mysql_error());
            while($info = mysql_fetch_array( $check )) { 
                echo("<b1> Tu ultimo mensaje enviado fue: </b1><b2>" . $info['texto'] . " enviado el " . $info['fecha'] . "</b2>");

That only a part of the code of course, the think is, Firefox and Chrome display the code above like this: that as you can see have the styles applied. But when i see the code from IE 8 (even 7 or 6) this is what you see: So, what do you think?