label {
    display:block;
    margin-top:10px;
    letter-spacing:1px;
}
 
.principal {
    display:block;
    margin:0 auto;
    width:100%;
    color: #666666;
    font-family:Arial;
}
 
form {
    margin:0 auto;
    width:100%;
}
 
input, textarea {
    width:100%;
    height:35px;
    background:#666666;
    border:2px solid #f6f6f6;
    padding:5px;
    margin-top:1px;
    font-size:20px;
    color:#ffffff;
     box-sizing: border-box;
}
 
textarea {
    height:150px;
}
#submit {
    width:85px;
    height:35px;
    border:none;
    margin-top:20px;
    cursor:pointer;
}