diff --git a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js
index 4bc257a..e679f7e 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js
+++ b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js
@@ -10189,16 +10189,16 @@ function drawSpectrum(data) {
     spectrumGl.drawPoints(spectrumTmpMarkerPoints, Math.max(2, dpr * 1.6), cssColorToRgba(pal.waveformPeak));
   }
 
-  // ── Bandplan WebGL strip (bottom of spectrum, above waterfall) ──
+  // ── Bandplan WebGL strip (top of spectrum, above waterfall) ──
   if (bandplanRegion !== "off" && bandplanData) {
     const bpSegs = bandplanVisibleSegments(bandplanRegion, range.visLoHz, range.visHiHz);
     if (bpSegs.length > 0) {
       const bpH = Math.round(BANDPLAN_STRIP_CSS_HEIGHT * dpr);
-      const bpY = H - bpH;
+      const bpY = 0;
       // Dark backdrop so segments are readable over the spectrum fill.
       spectrumGl.fillRect(0, bpY, W, bpH, [0.07, 0.09, 0.15, 0.82]);
-      // Thin separator line at top of bandplan strip.
-      spectrumGl.drawSegments([0, bpY, W, bpY],
+      // Thin separator line at bottom of bandplan strip.
+      spectrumGl.drawSegments([0, bpY + bpH, W, bpY + bpH],
         [1, 1, 1, 0.08], Math.max(1, dpr * 0.5));
       const bpVerts = [];
       for (const seg of bpSegs) {
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css
index 0e296e1..9af5762 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css
+++ b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css
@@ -3303,10 +3303,10 @@ button:focus-visible, input:focus-visible, select:focus-visible {
 
 /* ── WebGL overlay mode ── When the spectrum canvas is visible the coloured
    segments are rendered via WebGL.  The DOM strip repositions itself as a
-   transparent label overlay at the bottom of the spectrum canvas. */
+   transparent label overlay at the top of the spectrum canvas. */
 #spectrum-bandplan-strip.bp-webgl {
   position: absolute;
-  top: calc(var(--spectrum-plot-height) - 18px);
+  top: 0;
   left: 0;
   right: 0;
   background: transparent;