/* ===== BASE & RESET ===== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #dbeafe;
    --success: #16a34a;
    --success-light: #dcfce7;
    --danger: #dc2626;
    --danger-light: #fee2e2;
    --warning: #f59e0b;
    --warning-light: #fef3c7;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --radius: 10px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--gray-100);
    color: var(--gray-800);
    min-height: 100vh;
    line-height: 1.6;
}

/* ===== APP CONTAINER ===== */
.app-container {
    max-width: 960px;
    margin: 0 auto;
    padding: 20px 16px 40px;
}

/* ===== HEADER ===== */
.app-header {
    text-align: center;
    margin-bottom: 24px;
}
.header-content .logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
}
.header-content .logo i {
    font-size: 28px;
    color: var(--primary);
}
.header-content h1 {
    font-size: 24px;
    font-weight: 700;
    color: var(--gray-900);
}
.header-content .subtitle {
    color: var(--gray-500);
    font-size: 14px;
    margin-top: 4px;
}

/* ===== PROGRESS BAR ===== */
.progress-bar {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0;
    margin-bottom: 28px;
    padding: 0 20px;
}
.step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    position: relative;
}
.step-circle {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
    background: var(--gray-200);
    color: var(--gray-500);
    transition: all 0.3s;
}
.step span {
    font-size: 12px;
    font-weight: 500;
    color: var(--gray-400);
    white-space: nowrap;
    transition: all 0.3s;
}
.step.active .step-circle {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 0 0 4px var(--primary-light);
}
.step.active span {
    color: var(--primary);
    font-weight: 600;
}
.step.completed .step-circle {
    background: var(--success);
    color: #fff;
}
.step.completed span {
    color: var(--success);
}
.step-line {
    flex: 1;
    height: 3px;
    background: var(--gray-200);
    margin: 0 8px;
    margin-bottom: 22px;
    border-radius: 2px;
    transition: background 0.3s;
    min-width: 40px;
    max-width: 100px;
}
.step-line.active {
    background: var(--primary);
}

/* ===== PANELS ===== */
.step-panel {
    display: none;
}
.step-panel.active {
    display: block;
    animation: fadeIn 0.3s ease;
}
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}
.panel-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow);
    border: 1px solid var(--gray-200);
}
.panel-card h2 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 6px;
    display: flex;
    align-items: center;
    gap: 10px;
}
.panel-card h2 i {
    color: var(--primary);
}
.panel-card > p {
    color: var(--gray-500);
    font-size: 14px;
    margin-bottom: 20px;
}

/* ===== UPLOAD ZONE ===== */
.upload-zone {
    border: 2px dashed var(--gray-300);
    border-radius: var(--radius);
    padding: 48px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
    background: var(--gray-50);
}
.upload-zone:hover, .upload-zone.dragover {
    border-color: var(--primary);
    background: var(--primary-light);
}
.upload-zone i {
    font-size: 40px;
    color: var(--gray-400);
    margin-bottom: 12px;
}
.upload-zone:hover i, .upload-zone.dragover i {
    color: var(--primary);
}
.upload-zone p {
    color: var(--gray-600);
    font-size: 15px;
}
.upload-zone p.small {
    color: var(--gray-400);
    font-size: 13px;
    margin-top: 4px;
}

/* ===== FILE INFO ===== */
.file-info {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 14px 18px;
    background: var(--success-light);
    border-radius: var(--radius);
    margin-top: 16px;
    border: 1px solid #bbf7d0;
}
.file-info i {
    color: var(--success);
    font-size: 20px;
}
.file-info #fileName {
    font-weight: 600;
    color: var(--gray-800);
}
.file-info #fileRows {
    color: var(--gray-500);
    font-size: 13px;
    margin-left: auto;
}
.file-info .btn-small {
    margin-left: 8px;
}
.hidden {
    display: none !important;
}

/* ===== MAPPING GRID ===== */
.mapping-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-bottom: 24px;
}
.mapping-item {
    display: flex;
    flex-direction: column;
    gap: 4px;
}
.mapping-item label {
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-600);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.mapping-item select {
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    font-family: inherit;
    background: #fff;
    color: var(--gray-800);
    cursor: pointer;
}
.mapping-item select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}
.mapping-item .required-star {
    color: var(--danger);
}

/* ===== PREVIEW TABLE ===== */
.preview-section {
    margin-top: 16px;
}
.preview-section h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.preview-section h3 i {
    color: var(--primary);
}
.table-wrapper {
    overflow-x: auto;
    border: 1px solid var(--gray-200);
    border-radius: 8px;
}
#previewTable {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
}
#previewTable th {
    background: var(--gray-50);
    font-weight: 600;
    text-align: left;
    padding: 10px 12px;
    border-bottom: 2px solid var(--gray-200);
    white-space: nowrap;
    color: var(--gray-700);
}
#previewTable td {
    padding: 8px 12px;
    border-bottom: 1px solid var(--gray-100);
    white-space: nowrap;
    color: var(--gray-600);
}
#previewTable tr:last-child td {
    border-bottom: none;
}

/* ===== CONFIG ===== */
.config-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 24px;
}
.config-card {
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: 8px;
    padding: 20px;
}
.config-card h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.config-card h3 i {
    color: var(--primary);
}
.config-option {
    margin-bottom: 14px;
}
.config-option:last-child {
    margin-bottom: 0;
}
.config-option > label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 6px;
}
.config-option select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    font-family: inherit;
    background: #fff;
    cursor: pointer;
}
.config-option select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}
.config-option input[type="checkbox"] {
    margin-right: 6px;
    accent-color: var(--primary);
}
.config-hint {
    font-size: 12px;
    color: var(--gray-400);
    margin-top: 4px;
}
.config-hint code {
    background: var(--gray-200);
    padding: 1px 5px;
    border-radius: 3px;
    font-size: 11px;
}
.config-summary {
    grid-column: 1 / -1;
}
.config-summary .summary-row {
    display: flex;
    justify-content: space-between;
    padding: 6px 0;
    border-bottom: 1px solid var(--gray-200);
    font-size: 14px;
}
.config-summary .summary-row:last-child {
    border-bottom: none;
}
.config-summary .summary-label {
    color: var(--gray-500);
}
.config-summary .summary-value {
    font-weight: 600;
    color: var(--gray-800);
}

/* ===== BUTTONS ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.2s;
}
.btn-primary {
    background: var(--primary);
    color: #fff;
}
.btn-primary:hover {
    background: var(--primary-dark);
}
.btn-secondary {
    background: var(--gray-200);
    color: var(--gray-700);
}
.btn-secondary:hover {
    background: var(--gray-300);
}
.btn-success {
    background: var(--success);
    color: #fff;
}
.btn-success:hover {
    background: #15803d;
}
.btn-danger {
    background: var(--danger);
    color: #fff;
}
.btn-danger:hover {
    background: #b91c1c;
}
.btn-small {
    padding: 4px 10px;
    font-size: 12px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    background: var(--danger-light);
    color: var(--danger);
    font-weight: 600;
    transition: all 0.2s;
}
.btn-small:hover {
    background: var(--danger);
    color: #fff;
}
.btn-large {
    padding: 14px 28px;
    font-size: 16px;
}
.btn-row {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
    margin-top: 20px;
}

/* ===== XML PREVIEW ===== */
.xml-preview-section {
    margin: 20px 0;
}
.xml-preview-section h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.xml-preview-section h3 i {
    color: var(--primary);
}
.file-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 12px;
}
.file-tab {
    padding: 6px 14px;
    font-size: 12px;
    font-weight: 600;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    background: #fff;
    cursor: pointer;
    font-family: inherit;
    transition: all 0.2s;
    color: var(--gray-600);
}
.file-tab:hover {
    border-color: var(--primary);
    color: var(--primary);
}
.file-tab.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}
.xml-preview-wrapper {
    border: 1px solid var(--gray-200);
    border-radius: 8px;
    overflow: hidden;
}
.xml-preview {
    background: var(--gray-900);
    color: #e5e7eb;
    padding: 20px;
    font-size: 13px;
    line-height: 1.7;
    overflow-x: auto;
    max-height: 500px;
    overflow-y: auto;
    white-space: pre;
    font-family: 'Courier New', Courier, monospace;
}

/* ===== RESULT INFO ===== */
#resultInfo {
    background: var(--success-light);
    border: 1px solid #bbf7d0;
    border-radius: 8px;
    padding: 16px 20px;
    margin-bottom: 16px;
}
#resultInfo .result-header {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 8px;
}
#resultInfo .result-header i {
    color: var(--success);
    font-size: 20px;
}
#resultInfo .result-header h3 {
    font-size: 16px;
    font-weight: 700;
    color: var(--success);
}
#resultInfo .result-stats {
    display: flex;
    gap: 20px;
    font-size: 14px;
    color: var(--gray-700);
}
#resultInfo .result-stats strong {
    color: var(--gray-900);
}

/* ===== BACKORDER UI ===== */
.backorder-sub {
    margin-top: 10px;
}
.specific-order-input-row {
    display: flex;
    gap: 8px;
    align-items: center;
}
.specific-order-input-row .config-input {
    flex: 1;
}
.btn-small-add {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 8px 14px;
    border: none;
    border-radius: 6px;
    font-size: 13px;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    background: var(--primary);
    color: #fff;
    white-space: nowrap;
    transition: all 0.2s;
}
.btn-small-add:hover {
    background: var(--primary-dark);
}
.order-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: 10px;
    min-height: 28px;
}
.order-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    background: var(--primary-light);
    color: var(--primary-dark);
    border: 1px solid #93c5fd;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}
.tag-remove {
    background: none;
    border: none;
    color: var(--primary);
    font-size: 16px;
    font-weight: 700;
    cursor: pointer;
    padding: 0;
    line-height: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    transition: all 0.15s;
}
.tag-remove:hover {
    background: var(--danger);
    color: #fff;
}
.no-tags-hint {
    font-size: 12px;
    color: var(--gray-400);
    font-style: italic;
}
.order-hint-list {
    color: var(--gray-500);
    font-weight: 500;
}
.order-checkbox-list {
    max-height: 160px;
    overflow-y: auto;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    background: #fff;
    padding: 8px 10px;
}
.order-checkbox-item {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 4px 0;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-700);
    cursor: pointer;
}
.order-checkbox-item:hover {
    color: var(--primary);
}
.order-checkbox-item input[type="checkbox"] {
    accent-color: var(--primary);
    margin: 0;
}
.config-input {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    font-family: inherit;
    background: #fff;
}
.config-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}
#backorderOptions {
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px dashed var(--gray-300);
}
#resultInfo .result-stats {
    display: flex;
    flex-wrap: wrap;
    gap: 12px 20px;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    .app-container {
        padding: 12px 10px 30px;
    }
    .panel-card {
        padding: 18px;
    }
    .mapping-grid {
        grid-template-columns: 1fr;
    }
    .config-grid {
        grid-template-columns: 1fr;
    }
    .header-content h1 {
        font-size: 20px;
    }
    .btn-row {
        flex-wrap: wrap;
    }
    .progress-bar {
        padding: 0 8px;
    }
    .step span {
        font-size: 10px;
    }
}