diff --git a/Controllers/QRController.cs b/Controllers/QRController.cs
index 676492f..7784cd6 100644
--- a/Controllers/QRController.cs
+++ b/Controllers/QRController.cs
@@ -300,6 +300,10 @@ namespace QRRapidoApp.Controllers
             var requestId = Guid.NewGuid().ToString("N")[..8];
             var userId = User?.FindFirst(ClaimTypes.NameIdentifier)?.Value;
             var isAuthenticated = User?.Identity?.IsAuthenticated ?? false;
+
+            // DEBUG: Log detalhado dos parâmetros recebidos
+            _logger.LogInformation("🔍 [DEBUG] GenerateRapidWithLogo called - RequestId: {RequestId}, ApplyLogoColorization: {ApplyLogoColorization}, LogoSizePercent: {LogoSizePercent}, HasLogo: {HasLogo}", 
+                requestId, request.ApplyLogoColorization, request.LogoSizePercent, request.HasLogo);
             
             using (_logger.BeginScope(new Dictionary<string, object>
             {
diff --git a/Services/QRRapidoService.cs b/Services/QRRapidoService.cs
index 92f6867..e8f872f 100644
--- a/Services/QRRapidoService.cs
+++ b/Services/QRRapidoService.cs
@@ -265,7 +265,12 @@ namespace QRRapidoApp.Services
                         }));
                     
                     using var outputStream = new MemoryStream();
-                    resizedImage.Save(outputStream, new PngEncoder());
+                    // Preservar formato e cores originais ao redimensionar
+                    resizedImage.Save(outputStream, new PngEncoder
+                    {
+                        ColorType = PngColorType.RgbWithAlpha,
+                        CompressionLevel = PngCompressionLevel.DefaultCompression
+                    });
                     var resizedBytes = outputStream.ToArray();
                     
                     _logger.LogInformation("Logo redimensionado: {OriginalSize} -> {NewSize} bytes", 
@@ -491,13 +496,16 @@ namespace QRRapidoApp.Services
                 var backgroundY = (qrImage.Height - backgroundSize) / 2;
                 
                 // MELHORIA: Aplicar colorização se solicitado
-                _logger.LogDebug("Processing logo - Apply colorization: {ApplyColorization}", 
-                    request.ApplyLogoColorization);
+                _logger.LogInformation("🎨 [LOGO DEBUG] Processing logo - ApplyColorization: {ApplyColorization}, PrimaryColor: {PrimaryColor}", 
+                    request.ApplyLogoColorization, request.PrimaryColor);
                 
                 using Image finalLogo = request.ApplyLogoColorization
                     ? ApplyLogoColorization(logoImage, request.PrimaryColor)
                     : logoImage.Clone(ctx => { }); // Create a copy to avoid disposing the original
                 
+                _logger.LogInformation("🎨 [LOGO DEBUG] Logo processing path: {Path}", 
+                    request.ApplyLogoColorization ? "COLORIZED" : "ORIGINAL_COLORS");
+                
                 if (finalLogo == null)
                 {
                     _logger.LogError("Final logo is null after processing, cannot apply logo overlay");
@@ -531,7 +539,11 @@ namespace QRRapidoApp.Services
                 // Convert back to byte array
                 _logger.LogDebug("Saving final image with logo overlay");
                 using var outputStream = new MemoryStream();
-                finalImage.Save(outputStream, new PngEncoder());
+                finalImage.Save(outputStream, new PngEncoder
+                {
+                    ColorType = PngColorType.RgbWithAlpha,
+                    CompressionLevel = PngCompressionLevel.DefaultCompression
+                });
                 var result = outputStream.ToArray();
                 
                 _logger.LogInformation("Logo overlay completed successfully - Final image size: {FinalSize} bytes", 
@@ -570,7 +582,7 @@ namespace QRRapidoApp.Services
                 _logger.LogDebug("Creating colorized image with dimensions {Width}x{Height}", 
                     originalLogo.Width, originalLogo.Height);
                 
-                // Apply colorization by processing each pixel
+                // Apply intelligent colorization: preserve light backgrounds, colorize dark elements
                 var colorizedLogo = originalLogo.Clone(ctx =>
                 {
                     ctx.ProcessPixelRowsAsVector4((span, point) =>
@@ -578,19 +590,36 @@ namespace QRRapidoApp.Services
                         for (int x = 0; x < span.Length; x++)
                         {
                             var pixel = span[x];
-                            // Preserve alpha, but colorize RGB channels based on luminance
+                            
+                            // Calculate luminance (brightness) of the pixel
                             var luminance = (pixel.X * 0.299f + pixel.Y * 0.587f + pixel.Z * 0.114f);
-                            span[x] = new Vector4(
-                                rgba.R / 255f * luminance,
-                                rgba.G / 255f * luminance,
-                                rgba.B / 255f * luminance,
-                                pixel.W  // Preserve alpha
-                            );
+                            
+                            // Define threshold for "background" vs "content"
+                            // Values above 0.8 (bright) are considered background and preserved
+                            var brightnessThreshold = 0.8f;
+                            
+                            if (luminance > brightnessThreshold)
+                            {
+                                // Preserve bright pixels (background) - keep original colors
+                                span[x] = pixel;
+                            }
+                            else
+                            {
+                                // Colorize dark pixels (content/drawings) with QR color
+                                // Use inverse luminance for intensity (darker pixels get more color)
+                                var intensity = Math.Max(0.1f, 1.0f - luminance);
+                                span[x] = new Vector4(
+                                    rgba.R / 255f * intensity,
+                                    rgba.G / 255f * intensity,
+                                    rgba.B / 255f * intensity,
+                                    pixel.W  // Preserve alpha
+                                );
+                            }
                         }
                     });
                 });
                 
-                _logger.LogDebug("Logo colorization completed successfully");
+                _logger.LogInformation("✨ Smart logo colorization completed - Preserving bright pixels (>0.8), colorizing dark content with {Color}", targetColor);
                 return colorizedLogo;
             }
             catch (Exception ex)
diff --git a/wwwroot/js/qr-speed-generator.js b/wwwroot/js/qr-speed-generator.js
index 3395c28..d05df0e 100644
--- a/wwwroot/js/qr-speed-generator.js
+++ b/wwwroot/js/qr-speed-generator.js
@@ -573,8 +573,8 @@ class QRRapidoGenerator {
             
             // NOVOS PARÂMETROS DE LOGO APRIMORADO
             const logoSettings = this.getLogoSettings();
-            formData.append('logoSizePercent', logoSettings.logoSizePercent.toString());
-            formData.append('applyLogoColorization', logoSettings.applyColorization.toString());
+            formData.append('LogoSizePercent', logoSettings.logoSizePercent.toString());
+            formData.append('ApplyLogoColorization', logoSettings.applyColorization.toString());
             
             // Add logo file
             formData.append('logo', logoUpload.files[0]);
@@ -586,8 +586,9 @@ class QRRapidoGenerator {
             console.log('🎨 Preparando FormData com logo:', {
                 logoFile: logoUpload.files[0].name,
                 logoSize: logoUpload.files[0].size + ' bytes',
-                logoSizePercent: logoSizeSlider?.value || logoSettings.logoSizePercent || '20',
-                colorization: logoColorizeToggle?.checked || logoSettings.applyColorization || false,
+                LogoSizePercent: logoSettings.logoSizePercent,
+                ApplyLogoColorization: logoSettings.applyColorization,
+                checkboxChecked: logoColorizeToggle?.checked,
                 endpoint: '/api/QR/GenerateRapidWithLogo'
             });