CSS - Responzywność

fieldset
{
    border: 0px;
    margin: 0px;
    margin-left: 20px;
    padding: 0px;
}

@media screen and (max-width: 700px)
{
    fieldset
    {
        margin-left: auto;
        margin-right: auto;
        padding: 0px
    }
}