Implement comprehensive mobile experience improvements for Add Fuel Record screen

- Add mobile-first modal design with full-screen layout and slide-up animation
- Optimize touch targets to minimum 44px with proper spacing
- Convert to single-column mobile layout stacking all form fields vertically
- Replace Bootstrap datepicker with native HTML5 date input on mobile
- Simplify tag selection with mobile-friendly chip input and touch targets
- Default to Simple mode on mobile with clear mode toggle
- Implement bottom sheet pattern with swipe-to-dismiss gesture
- Add mobile-specific CSS with touch feedback and proper breakpoints
- Implement progressive enhancement with mobile detection utilities

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Views/Vehicle/Gas/_GasModal.cshtml

@@ -56,7 +56,7 @@
     <form>
         <div class="form-group">
             <div class="row">
-                <div class="col-md-6 col-12">
+                <div class="col-md-6 col-12 mobile-single-column">
                     <input type="text" id="workAroundInput" style="height:0px; width:0px; display:none;">
                     <!-- Simple Mode Fields -->
                     <div id="simpleModeFields" style="@(useSimpleFuelEntry ? "" : "display:none;")">
@@ -136,7 +136,7 @@
                         @await Html.PartialAsync("_ExtraField", Model.GasRecord.ExtraFields)
                     </div>
                 </div>
-                <div class="col-md-6 col-12" id="secondColumnFields" style="@(useSimpleFuelEntry ? "display:none;" : "")">
+                <div class="col-md-6 col-12 mobile-single-column" id="secondColumnFields" style="@(useSimpleFuelEntry ? "display:none;" : "")">
                     <label for="gasRecordNotes">@translator.Translate(userLanguage,"Notes(optional)")<a class="link-underline link-underline-opacity-0" onclick="showLinks(this)"><i class="bi bi-markdown ms-2"></i></a></label>
                     <textarea id="gasRecordNotes" class="form-control" rows="5">@Model.GasRecord.Notes</textarea>
                     <div>

wwwroot/css/site.css

@@ -98,12 +98,292 @@ html {
         aspect-ratio: 1/1;
         border-style: dashed;
         border-width: 2px;
-        page-break-after: always;
     }
-    .recordSticker {
+}
+
+/* Mobile-First Modal Improvements */
+@media (max-width: 768px) {
+    /* Full-screen modal on mobile */
+    .modal-dialog {
+        margin: 0;
+        width: 100vw;
+        height: 100vh;
+        max-width: none;
+        max-height: none;
+    }
+    
+    .modal-content {
+        height: 100vh;
+        border-radius: 0;
+        border: none;
+        display: flex;
+        flex-direction: column;
+    }
+    
+    /* Slide-up animation for mobile modals */
+    .modal.fade .modal-dialog {
+        transform: translateY(100%);
+        transition: transform 0.3s ease-out;
+    }
+    
+    .modal.show .modal-dialog {
+        transform: translateY(0);
+    }
+    
+    .modal-body {
+        flex: 1;
+        overflow-y: auto;
+        padding: 1rem;
+    }
+    
+    .modal-header {
+        flex-shrink: 0;
+        padding: 1rem;
+        border-bottom: 1px solid #dee2e6;
+    }
+    
+    .modal-footer {
+        flex-shrink: 0;
+        padding: 1rem;
+        border-top: 1px solid #dee2e6;
+    }
+    
+    /* Touch-friendly targets - minimum 44px */
+    .btn {
+        min-height: 44px;
+        min-width: 44px;
+        padding: 0.75rem 1rem;
+    }
+    
+    .btn-sm {
+        min-height: 44px;
+        min-width: 44px;
+        padding: 0.5rem 0.75rem;
+    }
+    
+    .btn-close {
+        width: 44px;
+        height: 44px;
+        padding: 0.75rem;
+    }
+    
+    .form-control {
+        min-height: 44px;
+        padding: 0.75rem;
+        font-size: 16px; /* Prevents zoom on iOS */
+    }
+    
+    .form-select {
+        min-height: 44px;
+        padding: 0.75rem;
+        font-size: 16px;
+    }
+    
+    .form-check-input {
+        width: 1.5rem;
+        height: 1.5rem;
+        margin-top: 0.25rem;
+    }
+    
+    .form-check-label {
+        min-height: 44px;
+        display: flex;
+        align-items: center;
+        padding-left: 0.5rem;
+    }
+    
+    .input-group-text {
+        min-height: 44px;
+        display: flex;
+        align-items: center;
+        justify-content: center;
+    }
+    
+    /* Single column layout on mobile */
+    .col-md-6 {
+        flex: 0 0 100% !important;
+        max-width: 100% !important;
+    }
+    
+    /* Mobile form spacing */
+    .form-group {
+        margin-bottom: 1.5rem;
+    }
+    
+    .form-group label {
+        margin-bottom: 0.75rem;
+        font-weight: 500;
+    }
+    
+    .form-group input,
+    .form-group select,
+    .form-group textarea {
+        margin-bottom: 1rem;
+    }
+    
+    /* Simplified header layout on mobile */
+    .modal-header .d-flex {
+        flex-direction: column;
+        align-items: stretch !important;
+    }
+    
+    .modal-header .modal-title {
+        margin-bottom: 1rem;
+        text-align: center;
+    }
+    
+    .modal-header .form-check {
+        justify-content: center;
+        margin-bottom: 0.5rem;
+    }
+    
+    .modal-header .btn-close {
+        position: absolute;
+        top: 1rem;
+        right: 1rem;
+        margin: 0;
+    }
+    
+    /* Mobile-friendly footer buttons */
+    .modal-footer {
+        display: flex;
+        flex-direction: column;
+        gap: 0.5rem;
+    }
+    
+    .modal-footer .btn {
+        width: 100%;
+        margin: 0;
+    }
+    
+    .modal-footer .btn:first-child {
+        order: 2; /* Move delete button to bottom */
+    }
+    
+    .modal-footer .btn:last-child {
+        order: 1; /* Move primary action to top */
+    }
+    
+    .modal-footer .btn:nth-child(2) {
+        order: 3; /* Cancel button in middle */
+    }
+    
+    /* Bottom sheet pattern for mobile */
+    .modal-content {
+        position: relative;
+    }
+    
+    .modal-content::before {
+        content: '';
+        position: absolute;
+        top: 8px;
+        left: 50%;
+        transform: translateX(-50%);
+        width: 40px;
+        height: 4px;
+        background-color: #dee2e6;
+        border-radius: 2px;
+        z-index: 1000;
+        cursor: grab;
+    }
+    
+    .modal-content::before:active {
+        cursor: grabbing;
+    }
+    
+    /* Touch feedback for interactive elements */
+    .btn:active,
+    .form-control:active,
+    .form-check-input:active {
+        transform: scale(0.98);
+        transition: transform 0.1s ease;
+    }
+    
+    /* Improved focus states for mobile */
+    .form-control:focus,
+    .form-select:focus {
+        border-color: #86b7fe;
+        box-shadow: 0 0 0 0.25rem rgba(13, 110, 253, 0.25);
+        outline: none;
+    }
+    
+    /* Mobile tag input styling */
+    .mobile-tag-input .bootstrap-tagsinput {
+        border-radius: 6px;
+        border: 1px solid #ced4da;
+    }
+    
+    .mobile-tag-input .bootstrap-tagsinput:focus-within {
+        border-color: #86b7fe;
+        box-shadow: 0 0 0 0.25rem rgba(13, 110, 253, 0.25);
+    }
+    
+    .mobile-tag-input .tag {
+        background-color: #0d6efd;
+        color: white;
+        border-radius: 4px;
+        margin: 2px;
+        padding: 4px 8px;
+        font-size: 14px;
+    }
+    
+    /* Enhanced mobile breakpoints for better responsiveness */
+    .mobile-single-column {
+        width: 100% !important;
+        max-width: 100% !important;
+        flex: 0 0 100% !important;
+    }
+    
+    /* Improved mobile modal animations */
+    .modal.fade .modal-dialog {
+        transform: translateY(100%);
+        transition: transform 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
+    }
+    
+    .modal.show .modal-dialog {
+        transform: translateY(0);
+    }
+    
+    /* Mobile keyboard adjustments */
+    .modal-body {
+        /* Prevent viewport scaling when keyboard appears */
+        position: relative;
+        overflow-y: auto;
+        -webkit-overflow-scrolling: touch;
+    }
+    
+    /* Accessibility improvements for mobile */
+    .form-label {
+        font-weight: 600;
+        color: #212529;
+        margin-bottom: 0.5rem;
+    }
+    
+    /* Error state improvements for mobile */
+    .is-invalid {
+        border-color: #dc3545 !important;
+        border-width: 2px !important;
+    }
+    
+    .is-invalid:focus {
+        box-shadow: 0 0 0 0.25rem rgba(220, 53, 69, 0.25) !important;
+    }
+    
+    /* Success state for mobile */
+    .is-valid {
+        border-color: #198754 !important;
+        border-width: 2px !important;
+    }
+    
+    .is-valid:focus {
+        box-shadow: 0 0 0 0.25rem rgba(25, 135, 84, 0.25) !important;
+    }
+}
+
+.recordSticker {
     height: 100%;
     page-break-after: always;
-    }
+}
     .stickerNote {
         height:100%;
     }

wwwroot/js/gasrecord.js

@@ -1,11 +1,133 @@
+// Mobile detection utility
+function isMobileDevice() {
+    return window.matchMedia("(max-width: 768px)").matches || 
+           /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent);
+}
+
+// Initialize form inputs based on device type
+function initializeFormInputs() {
+    if (isMobileDevice()) {
+        // Convert date input to native HTML5 on mobile
+        var dateInput = $('#gasRecordDate');
+        if (dateInput.length) {
+            dateInput.attr('type', 'date');
+            dateInput.removeClass('datepicker'); // Remove Bootstrap datepicker class
+        }
+        
+        // Default to simple mode on mobile
+        var modeToggle = $('#fuelEntryModeToggle');
+        if (modeToggle.length && !modeToggle.is(':checked')) {
+            modeToggle.prop('checked', true);
+            toggleFuelEntryMode(true);
+        }
+        
+        // Initialize mobile-friendly tag selector
+        initMobileTagSelector($("#gasRecordTag"));
+    } else {
+        // Use Bootstrap datepicker on desktop
+        initDatePicker($('#gasRecordDate'));
+        
+        // Use standard tag selector on desktop
+        initTagSelector($("#gasRecordTag"));
+    }
+}
+
+// Mobile-optimized tag selector
+function initMobileTagSelector(input) {
+    if (input.length) {
+        // Initialize with mobile-friendly options
+        input.tagsinput({
+            maxTags: 5, // Limit tags on mobile
+            trimValue: true,
+            confirmKeys: [13, 44, 32], // Enter, comma, space
+            focusClass: 'focus',
+            freeInput: true
+        });
+        
+        // Add mobile-specific styling
+        input.parent().addClass('mobile-tag-input');
+        
+        // Increase touch target size for mobile
+        input.parent().find('.bootstrap-tagsinput').css({
+            'min-height': '44px',
+            'padding': '8px',
+            'font-size': '16px' // Prevent zoom on iOS
+        });
+        
+        // Style the input within tags
+        input.parent().find('.bootstrap-tagsinput input').css({
+            'font-size': '16px',
+            'min-height': '30px'
+        });
+    }
+}
+
+// Swipe to dismiss functionality for mobile modals
+function initSwipeToDismiss() {
+    if (!isMobileDevice()) return;
+    
+    var modal = $('#gasRecordModal');
+    var modalContent = modal.find('.modal-content');
+    var startY = 0;
+    var currentY = 0;
+    var isDragging = false;
+    var threshold = 100; // Minimum swipe distance to dismiss
+    
+    // Touch start
+    modalContent.on('touchstart', function(e) {
+        startY = e.originalEvent.touches[0].clientY;
+        isDragging = true;
+        modalContent.css('transition', 'none');
+    });
+    
+    // Touch move
+    modalContent.on('touchmove', function(e) {
+        if (!isDragging) return;
+        
+        currentY = e.originalEvent.touches[0].clientY;
+        var deltaY = currentY - startY;
+        
+        // Only allow downward swipes
+        if (deltaY > 0) {
+            modalContent.css('transform', `translateY(${deltaY}px)`);
+        }
+    });
+    
+    // Touch end
+    modalContent.on('touchend', function(e) {
+        if (!isDragging) return;
+        
+        isDragging = false;
+        var deltaY = currentY - startY;
+        
+        modalContent.css('transition', 'transform 0.3s ease-out');
+        
+        if (deltaY > threshold) {
+            // Dismiss modal
+            modalContent.css('transform', 'translateY(100%)');
+            setTimeout(function() {
+                hideAddGasRecordModal();
+                modalContent.css('transform', '');
+            }, 300);
+        } else {
+            // Snap back
+            modalContent.css('transform', '');
+        }
+    });
+}
+
 function showAddGasRecordModal() {
     $.get(`/Vehicle/GetAddGasRecordPartialView?vehicleId=${GetVehicleId().vehicleId}`, function (data) {
         if (data) {
             $("#gasRecordModalContent").html(data);
-            //initiate datepicker
+            
-            initDatePicker($('#gasRecordDate'));
+            // Initialize inputs based on device type
-            initTagSelector($("#gasRecordTag"));
+            initializeFormInputs();
+            
             $('#gasRecordModal').modal('show');
+            
+            // Initialize swipe to dismiss for mobile
+            initSwipeToDismiss();
         }
     });
 }
@@ -25,11 +147,16 @@ function showEditGasRecordModal(gasRecordId, nocache) {
     $.get(`/Vehicle/GetGasRecordForEditById?gasRecordId=${gasRecordId}`, function (data) {
         if (data) {
             $("#gasRecordModalContent").html(data);
-            //initiate datepicker
+            
-            initDatePicker($('#gasRecordDate'));
+            // Initialize inputs based on device type
-            initTagSelector($("#gasRecordTag"));
+            initializeFormInputs();
+            
             $('#gasRecordModal').modal('show');
             bindModalInputChanges('gasRecordModal');
+            
+            // Initialize swipe to dismiss for mobile
+            initSwipeToDismiss();
+            
             $('#gasRecordModal').off('shown.bs.modal').on('shown.bs.modal', function () {
                 if (getGlobalConfig().useMarkDown) {
                     toggleMarkDownOverlay("gasRecordNotes");
@@ -441,10 +568,14 @@ function editMultipleGasRecords(ids) {
     $.post('/Vehicle/GetGasRecordsEditModal', { recordIds: ids }, function (data) {
         if (data) {
             $("#gasRecordModalContent").html(data);
-            //initiate datepicker
+            
-            initDatePicker($('#gasRecordDate'));
+            // Initialize inputs based on device type
-            initTagSelector($("#gasRecordTag"));
+            initializeFormInputs();
+            
             $('#gasRecordModal').modal('show');
+            
+            // Initialize swipe to dismiss for mobile
+            initSwipeToDismiss();
         }
     });
 }