function valid_Form(txtSellerName, txtEmail) {
    if (emptyField(txtSellerName)) {
        alert('Please enter name');
        txtSellerName.focus();
        return false;
    }

    if (emptyField(txtEmail)) {
        alert('Please enter email');
        txtEmail.focus();
        return false;
    }
    if (!validEmailId(txtEmail.value)) {
        alert('Please enter valid email(eg. you@domain.com)');
        txtEmail.focus();
        return false;
    }
}