.comment-form .comment-form-author, .comment-form .comment-form-email, .comment-form .comment-form-url, .comment-form .comment-form-phone {
    float: none !important;
}

.comment-form [for="author"], .comment-form [for="email"], .comment-form [for="url"], .comment-form [for="phone"] {
    float: none !important;
}

.comment-respond .comment-form-author, .comment-respond .comment-form-email, .comment-respond .comment-form-url, .comment-respond .comment-form-phone {
    float: none !important;
}

.comment-form .comment-form-email {
    margin: 0 !important;
}