diff --git a/src/Plugins/Nop.Plugin.Payments.TapPay/Views/PaymentInfo.cshtml b/src/Plugins/Nop.Plugin.Payments.TapPay/Views/PaymentInfo.cshtml
index 3aff7fd..2d40946 100755
--- a/src/Plugins/Nop.Plugin.Payments.TapPay/Views/PaymentInfo.cshtml
+++ b/src/Plugins/Nop.Plugin.Payments.TapPay/Views/PaymentInfo.cshtml
@@ -8,13 +8,70 @@
 <input type="hidden" asp-for="ServerType" />
 <input type="hidden" id="Prime" name="Prime" />
 
-<table width="100%" cellspacing="2" cellpadding="1" border="0">
+<style>
+    .tappay-table {
+        width: 100%;
+        border-collapse: separate;
+        border-spacing: 2px 10px;
+    }
+
+    .tappay-table label {
+        font-weight: 600;
+        color: #555;
+    }
+
+    .tappay-table .form-control,
+    .tappay-table .tappay-input {
+        height: 38px;
+        border: 1px solid #ccc;
+        border-radius: 4px;
+        padding: 8px;
+        box-sizing: border-box;
+        transition: border-color .2s ease, color .2s ease, box-shadow .2s ease;
+    }
+
+    .tappay-table .tappay-input {
+        width: 100%;
+    }
+
+    .tappay-table .has-error .form-control,
+    .tappay-table .has-error .tappay-input {
+        border-color: #e74c3c;
+        color: #e74c3c;
+        box-shadow: 0 0 0 1px rgba(231, 76, 60, 0.15);
+    }
+
+    .tappay-table .has-success .form-control,
+    .tappay-table .has-success .tappay-input {
+        border-color: #2ecc71;
+        color: #2ecc71;
+        box-shadow: 0 0 0 1px rgba(46, 204, 113, 0.15);
+    }
+
+    .tappay-table .phone-wrapper {
+        display: flex;
+        gap: 6px;
+        align-items: center;
+    }
+
+    .tappay-table .country-code-input {
+        max-width: 70px;
+        text-align: center;
+    }
+
+    .tappay-table .country-prefix {
+        font-weight: 600;
+        margin-right: 4px;
+    }
+</style>
+
+<table class="tappay-table" width="100%" cellspacing="2" cellpadding="1" border="0">
     <tr class="card-number-group">
         <td>
             <label><span id="cardtype"></span>@T("Payment.CardNumber"):</label>
         </td>
         <td>
-            <div class="form-control card-number" style="height: 20px"></div>
+            <div class="form-control card-number"></div>
         </td>
     </tr>
     <tr class="expiration-date-group">
@@ -22,7 +79,7 @@
             <label>@T("Payment.ExpirationDate"):</label>
         </td>
         <td>
-            <div class="form-control expiration-date" style="height: 20px"></div>
+            <div class="form-control expiration-date"></div>
         </td>
     </tr>
     <tr class="ccv-group">
@@ -30,23 +87,23 @@
             <label>@T("Payment.CardCode"):</label>
         </td>
         <td>
-            <div class="form-control ccv" style="height: 20px"></div>
+            <div class="form-control ccv"></div>
         </td>
     </tr>
-    <tr>
+    <tr class="name-en-group">
         <td>
             <label>@T("Payment.CardHolderName"):</label>
         </td>
         <td>
-            <input type="text" id="CardholderNameEn" name="CardholderNameEn" maxlength="45" placeholder="@T("Payment.CardHolderName")"/>
+            <input class="tappay-input" type="text" id="CardholderNameEn" name="CardholderNameEn" maxlength="45" placeholder="@T("Payment.CardHolderName")"/>
         </td>
     </tr>
-    <tr>
+    <tr class="email-group">
         <td>
             <label>@T("Payment.CardHolderEmail"):</label>
         </td>
         <td>
-            <input type="text" id="CardholderEmail" name="CardholderEmail" maxlength="40" placeholder="@T("Payment.CardHolderEmail")"/>
+            <input class="tappay-input" type="text" id="CardholderEmail" name="CardholderEmail" maxlength="40" placeholder="@T("Payment.CardHolderEmail")"/>
         </td>
     </tr>
     <tr id="phone_group">
@@ -54,14 +111,107 @@
             <label>@T("Payment.CardHolderPhone"):</label>
         </td>
         <td>
-            <div style="display: flex">
-                +<input type="tel" id="CardholderPhoneNumberCountryCode" name="CardholderPhoneNumberCountryCode" minlength="1" maxlength="3" placeholder="886" value="886"/>
-                <input type="tel" id="CardholderPhoneNumber" name="CardholderPhoneNumber" maxlength="16" placeholder="912345678"/>
+            <div class="phone-wrapper">
+                <div class="phone-code-group">
+                    <span class="country-prefix">+</span>
+                    <input class="tappay-input country-code-input" type="tel" id="CardholderPhoneNumberCountryCode" name="CardholderPhoneNumberCountryCode" minlength="1" maxlength="4" placeholder="886" value="886"/>
+                </div>
+                <div class="phone-number-group">
+                    <input class="tappay-input phone-number-input" type="tel" id="CardholderPhoneNumber" name="CardholderPhoneNumber" maxlength="16" placeholder="912345678"/>
+                </div>
             </div>
         </td>
     </tr>
 </table>
 <script asp-location="Footer">
+    var tappayCustomFieldState = {
+        nameEn: { valid: false, dirty: false },
+        email: { valid: false, dirty: false },
+        phoneCode: { valid: false, dirty: false },
+        phoneNumber: { valid: false, dirty: false }
+    };
+
+    var tappayCanGetPrime = false;
+
+    function setGroupState(selector, isValid, isDirty) {
+        var group = $(selector);
+        group.removeClass('has-error has-success');
+        if (isDirty) {
+            group.addClass(isValid ? 'has-success' : 'has-error');
+        }
+    }
+
+    function validateNameEn(markDirty) {
+        var value = $('#CardholderNameEn').val().trim();
+        tappayCustomFieldState.nameEn.dirty = tappayCustomFieldState.nameEn.dirty || markDirty || value.length > 0;
+        tappayCustomFieldState.nameEn.valid = /^[A-Za-z]+(?:[\s'-][A-Za-z]+)*$/.test(value) && value.length > 1;
+        setGroupState('.name-en-group', tappayCustomFieldState.nameEn.valid, tappayCustomFieldState.nameEn.dirty);
+        return tappayCustomFieldState.nameEn.valid;
+    }
+
+    function validateEmail(markDirty) {
+        var value = $('#CardholderEmail').val().trim();
+        tappayCustomFieldState.email.dirty = tappayCustomFieldState.email.dirty || markDirty || value.length > 0;
+        tappayCustomFieldState.email.valid = /^[^\s@@]+@@[^\s@@]+\.[^\s@@]+$/.test(value);
+        setGroupState('.email-group', tappayCustomFieldState.email.valid, tappayCustomFieldState.email.dirty);
+        return tappayCustomFieldState.email.valid;
+    }
+
+    function validatePhoneCode(markDirty) {
+        var value = $('#CardholderPhoneNumberCountryCode').val().trim();
+        tappayCustomFieldState.phoneCode.dirty = tappayCustomFieldState.phoneCode.dirty || markDirty || value.length > 0;
+        tappayCustomFieldState.phoneCode.valid = /^\d{1,4}$/.test(value);
+        setGroupState('#phone_group .phone-code-group', tappayCustomFieldState.phoneCode.valid, tappayCustomFieldState.phoneCode.dirty);
+        return tappayCustomFieldState.phoneCode.valid;
+    }
+
+    function validatePhoneNumber(markDirty) {
+        var value = $('#CardholderPhoneNumber').val().trim();
+        tappayCustomFieldState.phoneNumber.dirty = tappayCustomFieldState.phoneNumber.dirty || markDirty || value.length > 0;
+        tappayCustomFieldState.phoneNumber.valid = /^\d{4,16}$/.test(value);
+        setGroupState('#phone_group .phone-number-group', tappayCustomFieldState.phoneNumber.valid, tappayCustomFieldState.phoneNumber.dirty);
+        return tappayCustomFieldState.phoneNumber.valid;
+    }
+
+    function areCustomFieldsValid(markDirty) {
+        var nameValid = validateNameEn(markDirty);
+        var emailValid = validateEmail(markDirty);
+        var phoneCodeValid = validatePhoneCode(markDirty);
+        var phoneNumberValid = validatePhoneNumber(markDirty);
+
+        return nameValid && emailValid && phoneCodeValid && phoneNumberValid;
+    }
+
+    function updateSubmitButton(canGetPrime) {
+        if (typeof canGetPrime === 'boolean') {
+            tappayCanGetPrime = canGetPrime;
+        }
+        var canSubmit = tappayCanGetPrime && areCustomFieldsValid(false);
+        $('.button-1.payment-info-next-step-button').prop('disabled', !canSubmit);
+    }
+
+    $(function () {
+        $('#CardholderNameEn').on('input blur', function () {
+            validateNameEn(true);
+            updateSubmitButton();
+        });
+        $('#CardholderEmail').on('input blur', function () {
+            validateEmail(true);
+            updateSubmitButton();
+        });
+        $('#CardholderPhoneNumberCountryCode').on('input blur', function () {
+            validatePhoneCode(true);
+            updateSubmitButton();
+        });
+        $('#CardholderPhoneNumber').on('input blur', function () {
+            validatePhoneNumber(true);
+            updateSubmitButton();
+        });
+
+        // initialize default validation state
+        validatePhoneCode(false);
+        updateSubmitButton(false);
+    });
     
     $.ajax({
         url: "https://js.tappaysdk.com/sdk/tpdirect/v5.24.0", 
@@ -69,10 +219,10 @@
         cache: true,
         success: function() {
             TPDirect.setupSDK($('#AppId').val(), $('#AppKey').val(), $('#ServerType').val());
-            $('.button-1.payment-info-next-step-button').attr('disabled', true);
+            $('.button-1.payment-info-next-step-button').prop('disabled', true);
             $('.button-1.payment-info-next-step-button').removeAttr('onclick');
             $('.button-1.payment-info-next-step-button').off('click');
-            $('.button-1.payment-info-next-step-button').click(function() {
+            $('.button-1.payment-info-next-step-button').click(function(event) {
                 event.preventDefault();
                 
                 // fix keyboard issue in iOS device
@@ -81,6 +231,14 @@
                 const tappayStatus = TPDirect.card.getTappayFieldsStatus();
                 console.log(tappayStatus);
 
+                tappayCanGetPrime = tappayStatus.canGetPrime;
+
+                if (!areCustomFieldsValid(true)) {
+                    updateSubmitButton(tappayCanGetPrime);
+                    alert('請完整填寫持卡人資訊');
+                    return;
+                }
+
                 // Check TPDirect.card.getTappayFieldsStatus().canGetPrime before TPDirect.card.getPrime
                 if (tappayStatus.canGetPrime === false) {
                     alert('can not get prime');
@@ -173,13 +331,7 @@
                 // update.canGetPrime === true
                 //     --> you can call TPDirect.card.getPrime()
                 // const submitButton = document.querySelector('button[type="submit"]')
-                if (update.canGetPrime) {
-                    // submitButton.removeAttribute('disabled')
-                    $('.button-1.payment-info-next-step-button').removeAttr('disabled');
-                } else {
-                    // submitButton.setAttribute('disabled', true)
-                    $('.button-1.payment-info-next-step-button').attr('disabled', true);
-                }
+                updateSubmitButton(update.canGetPrime);
 
                 /* Change card type display when card type change */
                 /* ============================================== */