diff --git a/main.c b/main.c
index b8d7327..b209605 100644
--- a/main.c
+++ b/main.c
@@ -190,7 +190,8 @@ void DrawControlPanel(Michelson *mic) {
     int startY = 30;
     int contentWidth = UI_WIDTH - 40;
     int btnSize = 30;
-    int sliderWidth = contentWidth - (btnSize * 2) - 10; 
+    int spectrumWidth = contentWidth - (btnSize * 2) - 10;
+    int sliderWidth = spectrumWidth;
 
     GuiSetStyle(DEFAULT, TEXT_SIZE, 16);
     GuiSetStyle(DEFAULT, BASE_COLOR_NORMAL, 0x2D2D2DFF);    
@@ -215,11 +216,41 @@ void DrawControlPanel(Michelson *mic) {
     DrawText(TextFormat("Longueur d'onde: %.0f nm", mic->lambda), startX, startY, 20, COLOR_TEXT_SEC);
     
     float stepLambda = speedMode ? 10.0f : 1.0f;
-
+    
     if (GuiButtonRepeat((Rectangle){startX, startY + 30, btnSize, 25}, "-", shouldRepeat)) mic->lambda -= stepLambda;
-    GuiSlider((Rectangle){startX + btnSize + 5, startY + 30, sliderWidth - 40, 25}, NULL, NULL, &mic->lambda, 380, 780);
-    if (GuiButtonRepeat((Rectangle){startX + btnSize + sliderWidth - 30, startY + 30, btnSize, 25}, "+", shouldRepeat)) mic->lambda += stepLambda;
-    DrawRectangle(startX + contentWidth - 30, startY + 30, 30, 25, WavelengthToColor(mic->lambda));
+
+    Rectangle spectrumRect = {startX + btnSize + 5, startY + 30, spectrumWidth, 25};
+    
+    for (int i = 0; i < spectrumRect.width; i++) {
+        float prog = (float)i / spectrumRect.width;
+        float l = 380.0f + prog * (780.0f - 380.0f);
+        Color c = WavelengthToColor(l);
+        DrawLine(spectrumRect.x + i, spectrumRect.y, spectrumRect.x + i, spectrumRect.y + spectrumRect.height, c);
+    }
+    DrawRectangleLinesEx(spectrumRect, 1, DARKGRAY);
+
+    if (CheckCollisionPointRec(GetMousePosition(), spectrumRect)) {
+        if (IsMouseButtonDown(MOUSE_LEFT_BUTTON)) {
+            float mouseX = GetMouseX() - spectrumRect.x;
+            float ratio = mouseX / spectrumRect.width;
+            mic->lambda = 380.0f + ratio * (780.0f - 380.0f);
+        }
+    }
+
+    float currentRatio = (mic->lambda - 380.0f) / (780.0f - 380.0f);
+    if (currentRatio < 0) currentRatio = 0;
+    if (currentRatio > 1) currentRatio = 1;
+    
+    float cursorX = spectrumRect.x + currentRatio * spectrumRect.width;
+    
+    DrawLine(cursorX - 1, spectrumRect.y, cursorX - 1, spectrumRect.y + spectrumRect.height, BLACK);
+    DrawLine(cursorX + 1, spectrumRect.y, cursorX + 1, spectrumRect.y + spectrumRect.height, BLACK);
+    DrawLine(cursorX, spectrumRect.y, cursorX, spectrumRect.y + spectrumRect.height, WHITE);
+
+    if (GuiButtonRepeat((Rectangle){startX + btnSize + spectrumWidth + 10, startY + 30, btnSize, 25}, "+", shouldRepeat)) mic->lambda += stepLambda;
+    
+    if (mic->lambda < 380) mic->lambda = 380;
+    if (mic->lambda > 780) mic->lambda = 780;
 
 
     // Pos M1
diff --git a/michelson b/michelson
index 808344e..11f75cb 100755
Binary files a/michelson and b/michelson differ