Coins arrondis et fieldset sur ie

<article class="miniForm">
                <form action="" method="post">
                   <fieldset>
                        <legend>Contact rapide</legend>
                        <input type="email" placeholder="Votre email" required>
                        <textarea placeholder="Votre message"></textarea>
                        <input type="submit" value="Valider">
                    </fieldset> 
                </form>
            </article>  

/*MINI FORMULAIRE*/
article.miniForm {
    margin-top: -15px;
    margin-bottom: 10px;
}
.miniForm form {
    padding: -10px 0 0 0;
 }
/* CONDITION POUR FIREFOX */
@-moz-document url-prefix()
{
.miniForm form {
    padding: 0 0 0 0;
    margin-top: 15px;
    margin-bottom: -5px;
 }
}
/* FIN CONDITION */
.miniForm fieldset {
    margin: auto;
    padding:5px;
    width:160px;
    height: 170px;
    border:1px solid #fff;
    border-radius: 5px;
 }
/* CONDITION POUR FIREFOX */
@-moz-document url-prefix()
{
.miniForm fieldset {
    margin:10px auto;
    padding:10px;
    width:150px;
    height: 154px;
    border:1px solid #fff;
    border-radius: 5px;
 }
}
/* FIN CONDITION */

/* CONDITION POUR FIREFOX */
@-moz-document url-prefix()
{
.miniForm legend {
    text-align: left;
    color:#fff;
    font-weight:bold;
    margin-top: -10px;
 }
}
/* FIN CONDITION */

.miniForm legend {
    text-align: left;
    color:#fff;
    font-weight:bold;
    margin-bottom: -10px;
 }
.miniForm input {
    margin:0;
    padding:3px;
    width:140px;
    border:1px solid #ddd;
    border-radius: 5px;
 }
.miniForm textarea {
    margin:0;
    padding:3px;
    width:140px;
    height: 60px;
    border:1px solid #ddd;
    border-radius: 5px;
 }
.miniForm input[type=submit] 
	{
    float: right;
    margin-right: 5px;
    margin-top: 3px;
    margin-bottom: 5px;
    width:150px;
	height:30px;
	border-radius:5px;
	color:#393939;
    }
/* CONDITION POUR CHROME ET SAFARI */
@media screen and (-webkit-min-device-pixel-ratio:0) {
.miniForm input[type=submit] {   
    float: right;
    margin-right: 5px;
    margin-top: -7px;
    margin-bottom: 5px;
    width:150px;
	height:30px;
	border-radius:5px;
	color:#393939;
    }
}
/* CONDITION POUR FIREFOX */
@-moz-document url-prefix()
{
.miniForm input[type=submit] 
	{
    float: right;
    margin: auto;
    margin-top: -4px;
    width:150px;
	height:30px;
	border-radius:5px;
	color:#393939;
	}
}
/* FIN CONDITION */