Add guide box for chassis camera

web/app.css

@@ -19,14 +19,18 @@
     --border: #e5e7eb;
     --bg: #f9fafb;
     --surface: #ffffff;
-    --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.05);
-    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.08), 0 2px 4px -2px rgba(0,0,0,0.05);
+    --shadow: 0 1px 3px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.05);
+    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
 
     --radius: 8px;
     --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
 }
 
-* { box-sizing: border-box; margin: 0; padding: 0; }
+* {
+    box-sizing: border-box;
+    margin: 0;
+    padding: 0;
+}
 
 body {
     font-family: var(--font);
@@ -45,6 +49,7 @@ body {
     top: 0;
     z-index: 100;
 }
+
 .header-inner {
     max-width: 1100px;
     margin: 0 auto;
@@ -54,6 +59,7 @@ body {
     align-items: center;
     justify-content: space-between;
 }
+
 .header-brand {
     display: flex;
     align-items: center;
@@ -62,8 +68,16 @@ body {
     font-size: 15px;
     color: var(--text);
 }
-.header-brand svg { color: var(--blue); }
-.header-right { display: flex; align-items: center; gap: 12px; }
+
+.header-brand svg {
+    color: var(--blue);
+}
+
+.header-right {
+    display: flex;
+    align-items: center;
+    gap: 12px;
+}
 
 .status-dot {
     width: 8px;
@@ -71,8 +85,14 @@ body {
     border-radius: 50%;
     display: inline-block;
 }
-.status-dot.online { background: var(--green); }
-.status-dot.offline { background: var(--red); }
+
+.status-dot.online {
+    background: var(--green);
+}
+
+.status-dot.offline {
+    background: var(--red);
+}
 
 .btn-install {
     font-family: var(--font);
@@ -96,6 +116,7 @@ body {
     max-width: 100%;
     overflow-x: auto;
 }
+
 .tab-btn {
     font-family: var(--font);
     font-size: 14px;
@@ -109,7 +130,11 @@ body {
     white-space: nowrap;
     transition: color 0.15s, border-color 0.15s;
 }
-.tab-btn:hover { color: var(--text); }
+
+.tab-btn:hover {
+    color: var(--text);
+}
+
 .tab-btn.active {
     color: var(--blue);
     border-bottom-color: var(--blue);
@@ -122,8 +147,13 @@ body {
     padding: 24px 20px;
 }
 
-.tab-panel { display: none; }
-.tab-panel.active { display: block; }
+.tab-panel {
+    display: none;
+}
+
+.tab-panel.active {
+    display: block;
+}
 
 .two-col {
     display: grid;
@@ -131,8 +161,11 @@ body {
     gap: 20px;
     align-items: start;
 }
+
 @media (max-width: 768px) {
-    .two-col { grid-template-columns: 1fr; }
+    .two-col {
+        grid-template-columns: 1fr;
+    }
 }
 
 /* ── Panel ─────────────────────────────────────────────── */
@@ -142,19 +175,23 @@ body {
     border-radius: var(--radius);
     box-shadow: var(--shadow);
 }
+
 .panel-header {
     padding: 16px 20px;
     border-bottom: 1px solid var(--border);
 }
+
 .panel-header h2 {
     font-size: 15px;
     font-weight: 600;
 }
+
 .panel-desc {
     color: var(--text-2);
     font-size: 13px;
     margin-top: 2px;
 }
+
 .panel-body {
     padding: 20px;
     display: flex;
@@ -168,12 +205,15 @@ body {
     flex-direction: column;
     gap: 6px;
 }
+
 label {
     font-size: 13px;
     font-weight: 500;
     color: var(--text-2);
 }
-.input, .select {
+
+.input,
+.select {
     font-family: var(--font);
     font-size: 14px;
     color: var(--text);
@@ -185,7 +225,9 @@ label {
     transition: border-color 0.15s;
     width: 100%;
 }
-.input:focus, .select:focus {
+
+.input:focus,
+.select:focus {
     border-color: var(--blue);
 }
 
@@ -198,6 +240,7 @@ label {
     padding: 3px;
     gap: 2px;
 }
+
 .seg-btn {
     flex: 1;
     font-family: var(--font);
@@ -211,6 +254,7 @@ label {
     cursor: pointer;
     transition: all 0.15s;
 }
+
 .seg-btn.active {
     background: var(--surface);
     color: var(--text);
@@ -231,12 +275,20 @@ label {
     background: var(--bg);
     text-align: center;
 }
+
 .dropzone:hover {
     border-color: var(--blue);
     background: var(--blue-light);
 }
-.dropzone svg { color: var(--text-3); }
-.dropzone span { font-size: 13px; color: var(--text-2); }
+
+.dropzone svg {
+    color: var(--text-3);
+}
+
+.dropzone span {
+    font-size: 13px;
+    color: var(--text-2);
+}
 
 /* ── Camera ────────────────────────────────────────────── */
 .camera-step {
@@ -247,7 +299,12 @@ label {
     flex-direction: column;
     gap: 10px;
 }
-.camera-step.disabled { opacity: 0.4; pointer-events: none; }
+
+.camera-step.disabled {
+    opacity: 0.4;
+    pointer-events: none;
+}
+
 .step-label {
     font-size: 12px;
     font-weight: 600;
@@ -255,6 +312,7 @@ label {
     text-transform: uppercase;
     letter-spacing: 0.5px;
 }
+
 .cam-view {
     width: 100%;
     min-height: 160px;
@@ -262,11 +320,13 @@ label {
     border-radius: 6px;
     overflow: hidden;
 }
+
 .snap-preview {
     width: 100%;
     border-radius: 6px;
     display: block;
 }
+
 .cam-actions {
     display: flex;
     gap: 8px;
@@ -287,38 +347,66 @@ label {
     border: none;
     transition: all 0.15s;
 }
+
 .btn-primary {
     background: var(--blue);
     color: #fff;
 }
-.btn-primary:hover:not(:disabled) { background: #1d4ed8; }
-.btn-primary:disabled { opacity: 0.4; cursor: not-allowed; }
+
+.btn-primary:hover:not(:disabled) {
+    background: #1d4ed8;
+}
+
+.btn-primary:disabled {
+    opacity: 0.4;
+    cursor: not-allowed;
+}
+
 .btn-secondary {
     background: var(--surface);
     color: var(--text);
     border: 1px solid var(--border);
 }
-.btn-secondary:hover:not(:disabled) { background: var(--bg); }
-.btn-secondary:disabled { opacity: 0.4; cursor: not-allowed; }
+
+.btn-secondary:hover:not(:disabled) {
+    background: var(--bg);
+}
+
+.btn-secondary:disabled {
+    opacity: 0.4;
+    cursor: not-allowed;
+}
+
 .btn-ghost {
     background: transparent;
     color: var(--text-2);
     border: 1px solid var(--border);
 }
-.btn-ghost:hover { background: var(--bg); }
-.btn-full { width: 100%; }
+
+.btn-ghost:hover {
+    background: var(--bg);
+}
+
+.btn-full {
+    width: 100%;
+}
 
 /* ── Spinner ───────────────────────────────────────────── */
 .spinner {
     width: 14px;
     height: 14px;
-    border: 2px solid rgba(255,255,255,0.3);
+    border: 2px solid rgba(255, 255, 255, 0.3);
     border-top-color: currentColor;
     border-radius: 50%;
     animation: spin 0.7s linear infinite;
     display: inline-block;
 }
-@keyframes spin { to { transform: rotate(360deg); } }
+
+@keyframes spin {
+    to {
+        transform: rotate(360deg);
+    }
+}
 
 /* ── Empty State ───────────────────────────────────────── */
 .empty-state {
@@ -330,7 +418,11 @@ label {
     text-align: center;
     color: var(--text-3);
 }
-.empty-state p { font-size: 13px; max-width: 260px; }
+
+.empty-state p {
+    font-size: 13px;
+    max-width: 260px;
+}
 
 /* ── Result Banner ─────────────────────────────────────── */
 .result-banner {
@@ -342,25 +434,39 @@ label {
     margin-bottom: 16px;
     border: 1px solid;
 }
+
 .result-banner.EXACT {
     background: var(--green-light);
     border-color: #bbf7d0;
 }
+
 .result-banner.CORRECTED {
     background: var(--amber-light);
     border-color: #fde68a;
 }
+
 .result-banner.FAILED {
     background: var(--red-light);
     border-color: #fecaca;
 }
+
 .banner-title {
     font-size: 14px;
     font-weight: 600;
 }
-.EXACT .banner-title { color: var(--green); }
-.CORRECTED .banner-title { color: var(--amber); }
-.FAILED .banner-title { color: var(--red); }
+
+.EXACT .banner-title {
+    color: var(--green);
+}
+
+.CORRECTED .banner-title {
+    color: var(--amber);
+}
+
+.FAILED .banner-title {
+    color: var(--red);
+}
+
 .banner-sub {
     font-size: 12px;
     color: var(--text-2);
@@ -373,12 +479,17 @@ label {
     border-collapse: collapse;
     margin-bottom: 16px;
 }
+
 .result-table td {
     padding: 8px 0;
     border-bottom: 1px solid var(--border);
     vertical-align: top;
 }
-.result-table tr:last-child td { border-bottom: none; }
+
+.result-table tr:last-child td {
+    border-bottom: none;
+}
+
 .rt-label {
     font-size: 12px;
     font-weight: 500;
@@ -386,8 +497,15 @@ label {
     width: 40%;
     padding-right: 12px;
 }
-.rt-value { font-size: 14px; }
-.mono { font-family: 'Courier New', monospace; letter-spacing: 0.5px; }
+
+.rt-value {
+    font-size: 14px;
+}
+
+.mono {
+    font-family: 'Courier New', monospace;
+    letter-spacing: 0.5px;
+}
 
 /* ── Preprocessing Tabs ─────────────────────────────────── */
 .section-title {
@@ -398,12 +516,14 @@ label {
     letter-spacing: 0.5px;
     margin-bottom: 8px;
 }
+
 .pre-tabs {
     display: flex;
     gap: 4px;
     overflow-x: auto;
     margin-bottom: 10px;
 }
+
 .pre-tab {
     font-family: var(--font);
     font-size: 12px;
@@ -417,12 +537,17 @@ label {
     white-space: nowrap;
     transition: all 0.15s;
 }
-.pre-tab:hover { color: var(--text); }
+
+.pre-tab:hover {
+    color: var(--text);
+}
+
 .pre-tab.active {
     background: var(--blue);
     color: #fff;
     border-color: var(--blue);
 }
+
 .pre-img-wrap {
     border: 1px solid var(--border);
     border-radius: var(--radius);
@@ -430,6 +555,7 @@ label {
     background: #f3f4f6;
     position: relative;
 }
+
 .pre-img-wrap img {
     width: 100%;
     display: block;
@@ -437,6 +563,7 @@ label {
     object-fit: contain;
     background: #000;
 }
+
 .pre-ocr-label {
     padding: 8px 12px;
     font-size: 12px;
@@ -453,6 +580,7 @@ label {
     color: var(--text-2);
     margin-bottom: 6px;
 }
+
 .progress-track {
     height: 6px;
     background: var(--bg);
@@ -460,6 +588,7 @@ label {
     border: 1px solid var(--border);
     overflow: hidden;
 }
+
 .progress-fill {
     height: 100%;
     background: var(--blue);
@@ -472,9 +601,13 @@ label {
     grid-template-columns: repeat(4, 1fr);
     gap: 12px;
 }
+
 @media (max-width: 600px) {
-    .stats-grid { grid-template-columns: 1fr 1fr; }
+    .stats-grid {
+        grid-template-columns: 1fr 1fr;
+    }
 }
+
 .stat-card {
     border: 1px solid var(--border);
     border-radius: var(--radius);
@@ -482,27 +615,38 @@ label {
     text-align: center;
     background: var(--bg);
 }
+
 .stat-value {
     font-size: 22px;
     font-weight: 700;
     color: var(--text);
     line-height: 1.2;
 }
+
 .stat-label {
     font-size: 12px;
     color: var(--text-2);
     margin-top: 4px;
 }
 
-.table-toolbar { margin-bottom: 12px; }
-.search-input { max-width: 300px; }
+.table-toolbar {
+    margin-bottom: 12px;
+}
+
+.search-input {
+    max-width: 300px;
+}
+
+.table-scroll {
+    overflow-x: auto;
+}
 
-.table-scroll { overflow-x: auto; }
 .data-table {
     width: 100%;
     border-collapse: collapse;
     font-size: 13px;
 }
+
 .data-table th {
     text-align: left;
     padding: 8px 12px;
@@ -513,13 +657,20 @@ label {
     border-bottom: 1px solid var(--border);
     white-space: nowrap;
 }
+
 .data-table td {
     padding: 10px 12px;
     border-bottom: 1px solid var(--border);
     vertical-align: middle;
 }
-.data-table tbody tr:hover { background: var(--bg); }
-.data-table tbody tr:last-child td { border-bottom: none; }
+
+.data-table tbody tr:hover {
+    background: var(--bg);
+}
+
+.data-table tbody tr:last-child td {
+    border-bottom: none;
+}
 
 .badge {
     display: inline-block;
@@ -529,21 +680,34 @@ label {
     border-radius: 20px;
     letter-spacing: 0.2px;
 }
-.badge-exact { background: var(--green-light); color: var(--green); }
-.badge-corrected { background: var(--amber-light); color: var(--amber); }
-.badge-failed { background: var(--red-light); color: var(--red); }
+
+.badge-exact {
+    background: var(--green-light);
+    color: var(--green);
+}
+
+.badge-corrected {
+    background: var(--amber-light);
+    color: var(--amber);
+}
+
+.badge-failed {
+    background: var(--red-light);
+    color: var(--red);
+}
 
 /* ── Modal ─────────────────────────────────────────────── */
 .modal {
     position: fixed;
     inset: 0;
-    background: rgba(0,0,0,0.5);
+    background: rgba(0, 0, 0, 0.5);
     z-index: 500;
     display: flex;
     align-items: center;
     justify-content: center;
     padding: 20px;
 }
+
 .modal-box {
     background: var(--surface);
     border-radius: var(--radius);
@@ -552,6 +716,7 @@ label {
     max-width: 860px;
     overflow: hidden;
 }
+
 .modal-head {
     display: flex;
     justify-content: space-between;
@@ -561,6 +726,7 @@ label {
     font-weight: 600;
     font-size: 14px;
 }
+
 .modal-close-btn {
     background: none;
     border: none;
@@ -570,7 +736,12 @@ label {
     line-height: 1;
     padding: 0 4px;
 }
-.modal-body { padding: 20px; max-height: 75vh; overflow-y: auto; }
+
+.modal-body {
+    padding: 20px;
+    max-height: 75vh;
+    overflow-y: auto;
+}
 
 /* ── Toasts ────────────────────────────────────────────── */
 .toast-stack {
@@ -582,6 +753,7 @@ label {
     gap: 8px;
     z-index: 1000;
 }
+
 .toast {
     background: var(--surface);
     border: 1px solid var(--border);
@@ -596,14 +768,58 @@ label {
     align-items: center;
     gap: 8px;
 }
-.toast.success { border-left: 3px solid var(--green); }
-.toast.error   { border-left: 3px solid var(--red); }
-.toast.info    { border-left: 3px solid var(--blue); }
+
+.toast.success {
+    border-left: 3px solid var(--green);
+}
+
+.toast.error {
+    border-left: 3px solid var(--red);
+}
+
+.toast.info {
+    border-left: 3px solid var(--blue);
+}
+
 @keyframes slide-up {
-    from { opacity: 0; transform: translateY(8px); }
-    to   { opacity: 1; transform: translateY(0); }
+    from {
+        opacity: 0;
+        transform: translateY(8px);
+    }
+
+    to {
+        opacity: 1;
+        transform: translateY(0);
+    }
+}
+
+/* ADD THIS TO THE END OF YOUR EXISTING app.css — guide box for chassis camera capture */
+
+.chassis-video-wrap {
+    position: relative;
+    display: inline-block;
+    width: 100%;
+}
+
+.guide-box {
+    position: absolute;
+    top: 50%;
+    left: 50%;
+    transform: translate(-50%, -50%);
+    width: 70%;
+    height: 22%;
+    border: 3px solid #2563eb;
+    border-radius: 8px;
+    box-shadow: 0 0 0 9999px rgba(0, 0, 0, 0.45);
+    pointer-events: none;
+    z-index: 2;
 }
 
 /* ── Utilities ─────────────────────────────────────────── */
-.hidden { display: none !important; }
-.hidden-input { display: none; }
+.hidden {
+    display: none !important;
+}
+
+.hidden-input {
+    display: none;
+}

web/app.js

@@ -91,7 +91,7 @@ document.addEventListener('DOMContentLoaded', () => {
     function setupDropzone(dzId, inputId, nameId, isBarcode) {
         const dz = document.getElementById(dzId);
         const inp = document.getElementById(inputId);
-        const nm  = document.getElementById(nameId);
+        const nm = document.getElementById(nameId);
 
         dz.addEventListener('click', () => inp.click());
         dz.addEventListener('dragover', e => { e.preventDefault(); dz.classList.add('active'); });
@@ -158,19 +158,23 @@ document.addEventListener('DOMContentLoaded', () => {
                     validate();
                 });
             },
-            () => {}
+            () => { }
         ).catch(e => { toast(`Camera error: ${e}`, 'error'); startBarcodeCam.textContent = 'Start Camera'; qr = null; });
     });
 
     // ── Camera — chassis ─────────────────────────────────────
     let chassisStream = null;
-    const chassisVideo   = document.getElementById('chassis-video');
-    const chassisCanvas  = document.getElementById('chassis-canvas');
-    const snapContainer  = document.getElementById('chassis-snap-container');
-    const snapImg        = document.getElementById('chassis-snap-img');
+    const chassisVideo = document.getElementById('chassis-video');
+    const chassisCanvas = document.getElementById('chassis-canvas');
+    const snapContainer = document.getElementById('chassis-snap-container');
+    const snapImg = document.getElementById('chassis-snap-img');
     const startChassisCam = document.getElementById('start-chassis-cam');
-    const captureBtn     = document.getElementById('capture-chassis');
-    const retakeBtn      = document.getElementById('reset-chassis-snap');
+    const captureBtn = document.getElementById('capture-chassis');
+    const retakeBtn = document.getElementById('reset-chassis-snap');
+    const guideBox = document.getElementById('chassis-guide-box');
+
+    // Guide box region as fractions of the video frame (matches CSS: 70% wide, 22% tall, centered)
+    const GUIDE_BOX_FRACTION = { widthFrac: 0.70, heightFrac: 0.22, xFrac: 0.15, yFrac: 0.39 };
 
     startChassisCam.addEventListener('click', async () => {
         if (chassisStream) { stopChassisCamera(); return; }
@@ -180,21 +184,37 @@ document.addEventListener('DOMContentLoaded', () => {
             });
             chassisVideo.srcObject = chassisStream;
             chassisVideo.classList.remove('hidden');
+            guideBox.classList.remove('hidden');
             captureBtn.classList.remove('hidden');
             snapContainer.classList.add('hidden');
             retakeBtn.classList.add('hidden');
             startChassisCam.textContent = 'Stop';
-        } catch(e) { toast(`Camera error: ${e.message}`, 'error'); }
+        } catch (e) { toast(`Camera error: ${e.message}`, 'error'); }
     });
 
     captureBtn.addEventListener('click', () => {
-        chassisCanvas.width = chassisVideo.videoWidth;
-        chassisCanvas.height = chassisVideo.videoHeight;
-        chassisCanvas.getContext('2d').drawImage(chassisVideo, 0, 0);
+        const vw = chassisVideo.videoWidth;
+        const vh = chassisVideo.videoHeight;
+
+        // Crop to just the guide box region so OCR only sees the framed chassis strip
+        const cropX = vw * GUIDE_BOX_FRACTION.xFrac;
+        const cropY = vh * GUIDE_BOX_FRACTION.yFrac;
+        const cropW = vw * GUIDE_BOX_FRACTION.widthFrac;
+        const cropH = vh * GUIDE_BOX_FRACTION.heightFrac;
+
+        chassisCanvas.width = cropW;
+        chassisCanvas.height = cropH;
+        chassisCanvas.getContext('2d').drawImage(
+            chassisVideo,
+            cropX, cropY, cropW, cropH,   // source rect (the guide box area)
+            0, 0, cropW, cropH            // destination rect (full canvas)
+        );
+
         chassisCanvas.toBlob(blob => {
             chassisBlob = blob;
             snapImg.src = URL.createObjectURL(blob);
             chassisVideo.classList.add('hidden');
+            guideBox.classList.add('hidden');
             captureBtn.classList.add('hidden');
             snapContainer.classList.remove('hidden');
             retakeBtn.classList.remove('hidden');
@@ -215,12 +235,13 @@ document.addEventListener('DOMContentLoaded', () => {
         if (chassisStream) { chassisStream.getTracks().forEach(t => t.stop()); chassisStream = null; }
         chassisVideo.srcObject = null;
         chassisVideo.classList.add('hidden');
+        guideBox.classList.add('hidden');
         captureBtn.classList.add('hidden');
         startChassisCam.textContent = 'Start Camera';
     }
 
     function stopAllCameras() {
-        if (qr) { qr.stop().catch(() => {}); qr = null; startBarcodeCam.textContent = 'Start Camera'; }
+        if (qr) { qr.stop().catch(() => { }); qr = null; startBarcodeCam.textContent = 'Start Camera'; }
         stopChassisCamera();
     }
 
@@ -273,14 +294,14 @@ document.addEventListener('DOMContentLoaded', () => {
         const banner = document.getElementById('result-banner');
         banner.className = `result-banner ${d.status}`;
         const icons = {
-            EXACT:     '✓',
+            EXACT: '✓',
             CORRECTED: '~',
-            FAILED:    '✗'
+            FAILED: '✗'
         };
         const subs = {
-            EXACT:     'Raw OCR matched the barcode exactly.',
+            EXACT: 'Raw OCR matched the barcode exactly.',
             CORRECTED: 'Match achieved after error-correction.',
-            FAILED:    'OCR output could not be matched.'
+            FAILED: 'OCR output could not be matched.'
         };
         document.getElementById('banner-icon').textContent = icons[d.status];
         document.getElementById('banner-title').textContent = d.status === 'EXACT' ? 'Exact Match' : d.status === 'CORRECTED' ? 'Corrected Match' : 'No Match';
@@ -288,10 +309,10 @@ document.addEventListener('DOMContentLoaded', () => {
 
         // Table
         document.getElementById('res-expected').textContent = d.barcode_val;
-        document.getElementById('res-raw').textContent      = d.raw_ocr || '—';
+        document.getElementById('res-raw').textContent = d.raw_ocr || '—';
         document.getElementById('res-corrected').textContent = d.corrected_ocr || '—';
-        document.getElementById('res-conf').textContent     = `${Math.round(d.confidence * 100)}%`;
-        document.getElementById('res-filter').textContent   = d.winning_label || '—';
+        document.getElementById('res-conf').textContent = `${Math.round(d.confidence * 100)}%`;
+        document.getElementById('res-filter').textContent = d.winning_label || '—';
 
         // Preprocessing carousel
         const tabs = document.querySelectorAll('.pre-tab');
@@ -326,8 +347,8 @@ document.addEventListener('DOMContentLoaded', () => {
     }
 
     // ── Modal ────────────────────────────────────────────────
-    const modal     = document.getElementById('modal');
-    const modalImg  = document.getElementById('modal-img');
+    const modal = document.getElementById('modal');
+    const modalImg = document.getElementById('modal-img');
     const modalTitle = document.getElementById('modal-title');
 
     function openModal(url, title) {
@@ -341,6 +362,6 @@ document.addEventListener('DOMContentLoaded', () => {
 
     // ── Service Worker ───────────────────────────────────────
     if ('serviceWorker' in navigator) {
-        navigator.serviceWorker.register('/sw.js').catch(() => {});
+        navigator.serviceWorker.register('/sw.js').catch(() => { });
     }
-});
+});

web/index.html

@@ -1,5 +1,6 @@
 <!DOCTYPE html>
 <html lang="en">
+
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
@@ -13,13 +14,15 @@
     <link rel="stylesheet" href="app.css">
     <script src="https://unpkg.com/html5-qrcode" type="text/javascript"></script>
 </head>
+
 <body>
     <header class="header">
         <div class="header-inner">
             <div class="header-brand">
-                <svg width="22" height="22" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-                    <rect x="2" y="5" width="20" height="14" rx="2"/>
-                    <line x1="2" y1="10" x2="22" y2="10"/>
+                <svg width="22" height="22" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"
+                    stroke-linecap="round" stroke-linejoin="round">
+                    <rect x="2" y="5" width="20" height="14" rx="2" />
+                    <line x1="2" y1="10" x2="22" y2="10" />
                 </svg>
                 <span>Chassis OCR</span>
             </div>
@@ -64,7 +67,10 @@
                             <label>Barcode Image</label>
                             <div class="dropzone" id="barcode-dropzone">
                                 <input type="file" id="barcode-file" accept="image/*" class="hidden-input">
-                                <svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5"><path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4M17 8l-5-5-5 5M12 3v12"/></svg>
+                                <svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor"
+                                    stroke-width="1.5">
+                                    <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4M17 8l-5-5-5 5M12 3v12" />
+                                </svg>
                                 <span id="barcode-file-name">Drop or click to upload</span>
                             </div>
                         </div>
@@ -72,7 +78,10 @@
                             <label>Chassis Image</label>
                             <div class="dropzone" id="chassis-dropzone">
                                 <input type="file" id="chassis-file" accept="image/*" class="hidden-input">
-                                <svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5"><path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4M17 8l-5-5-5 5M12 3v12"/></svg>
+                                <svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor"
+                                    stroke-width="1.5">
+                                    <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4M17 8l-5-5-5 5M12 3v12" />
+                                </svg>
                                 <span id="chassis-file-name">Drop or click to upload</span>
                             </div>
                         </div>
@@ -87,7 +96,10 @@
                         </div>
                         <div class="camera-step disabled" id="cam-step-2">
                             <div class="step-label">Step 2 — Capture Chassis</div>
-                            <video id="chassis-video" autoplay playsinline class="cam-view hidden"></video>
+                            <div class="chassis-video-wrap">
+                                <video id="chassis-video" autoplay playsinline class="cam-view hidden"></video>
+                                <div id="chassis-guide-box" class="guide-box hidden"></div>
+                            </div>
                             <canvas id="chassis-canvas" class="hidden"></canvas>
                             <div id="chassis-snap-container" class="hidden">
                                 <img id="chassis-snap-img" class="snap-preview" src="" alt="Chassis snapshot">
@@ -120,7 +132,12 @@
                 </div>
                 <div class="panel-body" id="result-body">
                     <div id="result-empty" class="empty-state">
-                        <svg width="40" height="40" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5"><circle cx="12" cy="12" r="10"/><line x1="12" y1="8" x2="12" y2="12"/><line x1="12" y1="16" x2="12.01" y2="16"/></svg>
+                        <svg width="40" height="40" viewBox="0 0 24 24" fill="none" stroke="currentColor"
+                            stroke-width="1.5">
+                            <circle cx="12" cy="12" r="10" />
+                            <line x1="12" y1="8" x2="12" y2="12" />
+                            <line x1="12" y1="16" x2="12.01" y2="16" />
+                        </svg>
                         <p>Select a pair and run OCR to see results.</p>
                     </div>
 
@@ -179,4 +196,5 @@
 
     <script src="app.js"></script>
 </body>
-</html>
+
+</html>