diff --git a/frontend/src/app/core/constants/colors.const.ts b/frontend/src/app/core/constants/colors.const.ts
new file mode 100644
index 0000000..66b1336
--- /dev/null
+++ b/frontend/src/app/core/constants/colors.const.ts
@@ -0,0 +1,41 @@
+export interface ColorOption {
+  label: string;
+  value: string;
+  hex: string;
+  outOfStock?: boolean;
+}
+
+export interface ColorCategory {
+  name: string; // 'Glossy' | 'Matte'
+  colors: ColorOption[];
+}
+
+export const PRODUCT_COLORS: ColorCategory[] = [
+  {
+    name: 'Lucidi', // Glossy
+    colors: [
+      { label: 'Black', value: 'Black', hex: '#1a1a1a' }, // Not pure black for visibility
+      { label: 'White', value: 'White', hex: '#f5f5f5' },
+      { label: 'Red', value: 'Red', hex: '#d32f2f', outOfStock: true },
+      { label: 'Blue', value: 'Blue', hex: '#1976d2' },
+      { label: 'Green', value: 'Green', hex: '#388e3c' },
+      { label: 'Yellow', value: 'Yellow', hex: '#fbc02d' }
+    ]
+  },
+  {
+    name: 'Opachi', // Matte
+    colors: [
+      { label: 'Matte Black', value: 'Matte Black', hex: '#2c2c2c' }, // Lighter charcoal for matte
+      { label: 'Matte White', value: 'Matte White', hex: '#e0e0e0' },
+      { label: 'Matte Gray', value: 'Matte Gray', hex: '#757575' }
+    ]
+  }
+];
+
+export function getColorHex(value: string): string {
+    for (const cat of PRODUCT_COLORS) {
+        const found = cat.colors.find(c => c.value === value);
+        if (found) return found.hex;
+    }
+    return '#facf0a'; // Default Brand Color if not found
+}
diff --git a/frontend/src/app/features/calculator/calculator-page.component.ts b/frontend/src/app/features/calculator/calculator-page.component.ts
index ac8aefe..7122a4b 100644
--- a/frontend/src/app/features/calculator/calculator-page.component.ts
+++ b/frontend/src/app/features/calculator/calculator-page.component.ts
@@ -72,11 +72,14 @@ export class CalculatorPageComponent {
     
     details += `- File:\n`;
     req.items.forEach(item => {
-        details += `  * ${item.file.name} (Qtà: ${item.quantity})\n`;
+        details += `  * ${item.file.name} (Qtà: ${item.quantity}`;
+        if (item.color) {
+            details += `, Colore: ${item.color}`;
+        }
+        details += `)\n`;
     });
 
     if (req.mode === 'advanced') {
-       if (req.color) details += `- Colore: ${req.color}\n`;
        if (req.infillDensity) details += `- Infill: ${req.infillDensity}%\n`;
     }
 
diff --git a/frontend/src/app/features/calculator/components/upload-form/upload-form.component.html b/frontend/src/app/features/calculator/components/upload-form/upload-form.component.html
index 334fd93..e89b46d 100644
--- a/frontend/src/app/features/calculator/components/upload-form/upload-form.component.html
+++ b/frontend/src/app/features/calculator/components/upload-form/upload-form.component.html
@@ -3,7 +3,10 @@
   <div class="section">
     @if (selectedFile()) {
       <div class="viewer-wrapper">
-         <app-stl-viewer [file]="selectedFile()"></app-stl-viewer>
+         <app-stl-viewer 
+            [file]="selectedFile()"
+            [color]="getSelectedFileColor()">
+         </app-stl-viewer>
          <!-- Close button removed as requested -->
       </div>
     }
@@ -29,15 +32,25 @@
                     </div>
                     
                     <div class="card-body">
-                         <div class="qty-group">
-                            <label>Qtà</label>
-                            <input 
-                                type="number" 
-                                min="1" 
-                                [value]="item.quantity"
-                                (change)="updateItemQuantity(i, $event)"
-                                class="qty-input"
-                                (click)="$event.stopPropagation()">
+                        <div class="card-controls">
+                             <div class="qty-group">
+                                <label>QTÀ</label>
+                                <input 
+                                    type="number" 
+                                    min="1" 
+                                    [value]="item.quantity"
+                                    (change)="updateItemQuantity(i, $event)"
+                                    class="qty-input"
+                                    (click)="$event.stopPropagation()">
+                            </div>
+
+                            <div class="color-group">
+                                <label>COLORE</label>
+                                <app-color-selector 
+                                    [selectedColor]="item.color" 
+                                    (colorSelected)="updateItemColor(i, $event)">
+                                </app-color-selector>
+                            </div>
                         </div>
                         
                         <button type="button" class="btn-remove" (click)="removeItem(i); $event.stopPropagation()" title="Remove file">
@@ -81,12 +94,6 @@
 
   @if (mode() === 'advanced') {
     <div class="grid">
-         <app-select
-          formControlName="color"
-          [label]="'CALC.COLOR' | translate"
-          [options]="colors"
-        ></app-select>
-        
         <app-select
           formControlName="infillPattern"
           [label]="'CALC.PATTERN' | translate"
diff --git a/frontend/src/app/features/calculator/components/upload-form/upload-form.component.scss b/frontend/src/app/features/calculator/components/upload-form/upload-form.component.scss
index 1cee5e1..3331860 100644
--- a/frontend/src/app/features/calculator/components/upload-form/upload-form.component.scss
+++ b/frontend/src/app/features/calculator/components/upload-form/upload-form.component.scss
@@ -16,18 +16,18 @@
 /* Grid Layout for Files */
 .items-grid {
     display: grid;
-    grid-template-columns: 1fr;
-    gap: var(--space-3);
+    grid-template-columns: 1fr 1fr; /* Force 2 columns on mobile */
+    gap: var(--space-2); /* Tighten gap for mobile */
     margin-top: var(--space-4);
     margin-bottom: var(--space-4);
     
     @media(min-width: 640px) {
-        grid-template-columns: 1fr 1fr;
+        gap: var(--space-3);
     }
 }
 
 .file-card {
-    padding: var(--space-3);
+    padding: var(--space-2); /* Reduced from space-3 */
     background: var(--color-neutral-100);
     border: 1px solid var(--color-border);
     border-radius: var(--radius-md);
@@ -35,7 +35,9 @@
     cursor: pointer;
     display: flex;
     flex-direction: column;
-    gap: var(--space-2);
+    gap: 4px; /* Reduced gap */
+    position: relative; /* For absolute positioning of remove btn */
+    min-width: 0; /* Allow flex item to shrink below content size if needed */
     
     &:hover { border-color: var(--color-neutral-300); }
     &.active {
@@ -47,11 +49,13 @@
 
 .card-header {
     overflow: hidden;
+    padding-right: 25px; /* Adjusted */
+    margin-bottom: 2px;
 }
 
 .file-name { 
     font-weight: 500; 
-    font-size: 0.85rem; 
+    font-size: 0.8rem; /* Smaller font */
     color: var(--color-text);
     display: block;
     white-space: nowrap;
@@ -61,34 +65,64 @@
 
 .card-body {
     display: flex;
-    justify-content: space-between;
     align-items: center;
+    padding-top: 0;
 }
 
-.qty-group {
+.card-controls {
     display: flex;
-    align-items: center;
-    gap: var(--space-2);
-    label { font-size: 0.75rem; color: var(--color-text-muted); text-transform: uppercase; letter-spacing: 0.5px; }
+    align-items: flex-end; /* Align bottom of input and color circle */
+    gap: 16px; /* Space between Qty and Color */
+    width: 100%;
+}
+
+.qty-group, .color-group {
+    display: flex;
+    flex-direction: column; /* Stack label and input */
+    align-items: flex-start;
+    gap: 0px; 
+    
+    label { 
+        font-size: 0.6rem; 
+        color: var(--color-text-muted); 
+        text-transform: uppercase; 
+        letter-spacing: 0.5px; 
+        font-weight: 600;
+        margin-bottom: 2px;
+    }
+}
+
+.color-group {
+    align-items: flex-start; /* Align label left */
+    /* margin-right removed */
+    
+    /* Override margin in selector for this context */
+    ::ng-deep .color-selector-container {
+        margin-left: 0;
+    }
 }
 
 .qty-input {
-    width: 40px;
-    padding: 2px 4px;
+    width: 36px; /* Slightly smaller */
+    padding: 1px 2px;
     border: 1px solid var(--color-border);
     border-radius: var(--radius-sm);
     text-align: center;
-    font-size: 0.9rem;
+    font-size: 0.85rem;
     background: white;
+    height: 24px; /* Explicit height to match color circle somewhat */
     &:focus { outline: none; border-color: var(--color-brand); }
 }
 
 .btn-remove {
-    width: 24px;
-    height: 24px;
+    position: absolute;
+    top: 4px;
+    right: 4px;
+    width: 18px;
+    height: 18px;
     border-radius: 4px;
-    border: 1px solid transparent; // var(--color-border);
-    background: transparent; // white;
+    border: none;
+    background: transparent;
     color: var(--color-text-muted);
     font-weight: bold;
     cursor: pointer;
@@ -96,12 +130,11 @@
     align-items: center;
     justify-content: center;
     transition: all 0.2s;
-    font-size: 0.9rem;
+    font-size: 0.8rem;
     
     &:hover { 
         background: var(--color-danger-100); 
         color: var(--color-danger-500);
-        border-color: var(--color-danger-200);
     }
 }
 
diff --git a/frontend/src/app/features/calculator/components/upload-form/upload-form.component.ts b/frontend/src/app/features/calculator/components/upload-form/upload-form.component.ts
index 4229e3e..6415414 100644
--- a/frontend/src/app/features/calculator/components/upload-form/upload-form.component.ts
+++ b/frontend/src/app/features/calculator/components/upload-form/upload-form.component.ts
@@ -7,17 +7,20 @@ import { AppSelectComponent } from '../../../../shared/components/app-select/app
 import { AppDropzoneComponent } from '../../../../shared/components/app-dropzone/app-dropzone.component';
 import { AppButtonComponent } from '../../../../shared/components/app-button/app-button.component';
 import { StlViewerComponent } from '../../../../shared/components/stl-viewer/stl-viewer.component';
+import { ColorSelectorComponent } from '../../../../shared/components/color-selector/color-selector.component';
 import { QuoteRequest } from '../../services/quote-estimator.service';
+import { getColorHex } from '../../../../core/constants/colors.const';
 
 interface FormItem {
     file: File;
     quantity: number;
+    color: string;
 }
 
 @Component({
   selector: 'app-upload-form',
   standalone: true,
-  imports: [CommonModule, ReactiveFormsModule, TranslateModule, AppInputComponent, AppSelectComponent, AppDropzoneComponent, AppButtonComponent, StlViewerComponent],
+  imports: [CommonModule, ReactiveFormsModule, TranslateModule, AppInputComponent, AppSelectComponent, AppDropzoneComponent, AppButtonComponent, StlViewerComponent, ColorSelectorComponent],
   templateUrl: './upload-form.component.html',
   styleUrl: './upload-form.component.scss'
 })
@@ -44,15 +47,6 @@ export class UploadFormComponent {
     { label: 'Alta definizione', value: 'High' }
   ];
   
-  colors = [
-      { label: 'Black', value: 'Black' },
-      { label: 'White', value: 'White' },
-      { label: 'Gray', value: 'Gray' },
-      { label: 'Red', value: 'Red' },
-      { label: 'Blue', value: 'Blue' },
-      { label: 'Green', value: 'Green' },
-      { label: 'Yellow', value: 'Yellow' }
-  ];
   infillPatterns = [
       { label: 'Grid', value: 'grid' },
       { label: 'Gyroid', value: 'gyroid' },
@@ -69,7 +63,7 @@ export class UploadFormComponent {
       quality: ['Standard', Validators.required],
       notes: [''],
       // Advanced fields
-      color: ['Black'],
+      // Color removed from global form
       infillDensity: [20, [Validators.min(0), Validators.max(100)]],
       infillPattern: ['grid'],
       supportEnabled: [false]
@@ -85,7 +79,8 @@ export class UploadFormComponent {
         if (file.size > MAX_SIZE) {
             hasError = true;
         } else {
-            validItems.push({ file, quantity: 1 });
+            // Default color is Black
+            validItems.push({ file, quantity: 1, color: 'Black' });
         }
     }
 
@@ -129,6 +124,18 @@ export class UploadFormComponent {
       }
   }
 
+  // Helper to get color of currently selected file
+  getSelectedFileColor(): string {
+      const file = this.selectedFile();
+      if (!file) return '#facf0a'; // Default
+      
+      const item = this.items().find(i => i.file === file);
+      if (item) {
+          return getColorHex(item.color);
+      }
+      return '#facf0a';
+  }
+
   updateItemQuantity(index: number, event: Event) {
       const input = event.target as HTMLInputElement;
       let val = parseInt(input.value, 10);
@@ -141,6 +148,14 @@ export class UploadFormComponent {
       });
   }
 
+  updateItemColor(index: number, newColor: string) {
+      this.items.update(current => {
+          const updated = [...current];
+          updated[index] = { ...updated[index], color: newColor };
+          return updated;
+      });
+  }
+
   removeItem(index: number) {
       this.items.update(current => {
           const updated = [...current];
@@ -155,7 +170,7 @@ export class UploadFormComponent {
   onSubmit() {
     if (this.form.valid && this.items().length > 0) {
       this.submitRequest.emit({
-        items: this.items(), // Pass the items array
+        items: this.items(), // Pass the items array including colors
         ...this.form.value,
         mode: this.mode()
       });
diff --git a/frontend/src/app/features/calculator/services/quote-estimator.service.ts b/frontend/src/app/features/calculator/services/quote-estimator.service.ts
index 0d17653..de25a77 100644
--- a/frontend/src/app/features/calculator/services/quote-estimator.service.ts
+++ b/frontend/src/app/features/calculator/services/quote-estimator.service.ts
@@ -5,11 +5,11 @@ import { map, catchError } from 'rxjs/operators';
 import { environment } from '../../../../environments/environment';
 
 export interface QuoteRequest {
-  items: { file: File, quantity: number }[];
+  items: { file: File, quantity: number, color?: string }[];
   material: string;
   quality: string;
   notes?: string;
-  color?: string;
+  // color removed from global scope
   infillDensity?: number;
   infillPattern?: string;
   supportEnabled?: boolean;
@@ -69,8 +69,11 @@ export class QuoteEstimatorService {
              formData.append('machine', 'bambu_a1'); 
              formData.append('filament', this.mapMaterial(request.material));
              formData.append('quality', this.mapQuality(request.quality));
+             
+             // Send color for both modes if present, defaulting to Black
+             formData.append('material_color', item.color || 'Black');
+
              if (request.mode === 'advanced') {
-                if (request.color) formData.append('material_color', request.color);
                 if (request.infillDensity) formData.append('infill_density', request.infillDensity.toString());
                 if (request.infillPattern) formData.append('infill_pattern', request.infillPattern);
                 if (request.supportEnabled) formData.append('support_enabled', 'true');
diff --git a/frontend/src/app/shared/components/color-selector/color-selector.component.html b/frontend/src/app/shared/components/color-selector/color-selector.component.html
new file mode 100644
index 0000000..79df3df
--- /dev/null
+++ b/frontend/src/app/shared/components/color-selector/color-selector.component.html
@@ -0,0 +1,39 @@
+<div class="color-selector-container">
+  @if (isOpen()) {
+      <div class="backdrop" (click)="close()"></div>
+  }
+
+  <div 
+    class="color-circle trigger" 
+    [style.background-color]="getCurrentHex()"
+    [title]="selectedColor()"
+    (click)="toggleOpen()">
+  </div>
+
+  @if (isOpen()) {
+    <div class="color-popup">
+      @for (category of categories; track category.name) {
+        <div class="category">
+          <div class="category-name">{{ category.name }}</div>
+          <div class="colors-grid">
+            @for (color of category.colors; track color.value) {
+              <div 
+                class="color-item" 
+                (click)="selectColor(color)"
+                [class.disabled]="color.outOfStock">
+                
+                <div class="selection-ring" 
+                     [class.active]="selectedColor() === color.value"
+                     [class.out-of-stock]="color.outOfStock">
+                     <div class="color-circle small" [style.background-color]="color.hex"></div>
+                </div>
+                
+                <span class="color-name">{{ color.label }}</span>
+              </div>
+            }
+          </div>
+        </div>
+      }
+    </div>
+  }
+</div>
diff --git a/frontend/src/app/shared/components/color-selector/color-selector.component.scss b/frontend/src/app/shared/components/color-selector/color-selector.component.scss
new file mode 100644
index 0000000..3bf8b75
--- /dev/null
+++ b/frontend/src/app/shared/components/color-selector/color-selector.component.scss
@@ -0,0 +1,136 @@
+.color-selector-container {
+  position: relative;
+  display: inline-block;
+  // margin-left: 10px; // Handled by parent now
+}
+
+.backdrop {
+    position: fixed;
+    top: 0;
+    left: 0;
+    width: 100vw;
+    height: 100vh;
+    z-index: 999;
+    background: transparent;
+    cursor: default;
+}
+
+.color-circle {
+  width: 20px; /* Reduced from 24px */
+  height: 20px;
+  border-radius: 50%;
+  border: 2px solid #ddd;
+  cursor: pointer;
+  transition: transform 0.2s, box-shadow 0.2s;
+  box-shadow: 0 1px 2px rgba(0,0,0,0.1);
+
+  &.trigger:hover {
+    transform: scale(1.1);
+    box-shadow: 0 2px 4px rgba(0,0,0,0.15);
+  }
+
+  &.small {
+    width: 20px;
+    height: 20px;
+    border: 1px solid #eee;
+  }
+}
+
+.color-popup {
+  position: absolute;
+  top: calc(100% + 8px); // Explicit gap
+  left: -2px; // Align left edge with slight offset
+  background: white;
+  border: 1px solid #eee;
+  border-radius: 8px; /* Slightly tighter radius */
+  padding: 12px;
+  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
+  z-index: 1000;
+  width: 230px; /* Increased size */
+  
+  // Little triangle arrow
+  &::before {
+    content: '';
+    position: absolute;
+    top: -6px;
+    left: 8px; // Align arrow to left side near trigger
+    border-width: 0 6px 6px 6px;
+    border-style: solid;
+    border-color: transparent transparent white transparent;
+  }
+}
+
+.category {
+  margin-bottom: 12px;
+  
+  &:last-child {
+    margin-bottom: 0;
+  }
+}
+
+.category-name {
+  font-size: 11px;
+  text-transform: uppercase;
+  color: #888;
+  margin-bottom: 6px;
+  font-weight: 600;
+  letter-spacing: 0.5px;
+}
+
+.colors-grid {
+  display: grid;
+  grid-template-columns: repeat(3, 1fr); /* 3 columns for better alignment */
+  gap: 12px;
+}
+
+.color-item {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 4px;
+  cursor: pointer;
+  text-align: center;
+  
+  &:hover .selection-ring {
+    transform: scale(1.1);
+  }
+  
+  &.disabled {
+    cursor: not-allowed;
+    opacity: 0.6;
+    &:hover .selection-ring { transform: none; }
+  }
+}
+
+.selection-ring {
+  position: relative;
+  border-radius: 50%;
+  border: 2px solid transparent;
+  transition: all 0.2s;
+  padding: 2px; /* Space for ring */
+  
+  &.active {
+    border-color: var(--color-brand, #facf0a);
+    box-shadow: 0 0 0 1px var(--color-brand, #facf0a);
+  }
+  
+  &.out-of-stock::after {
+        content: '';
+        position: absolute;
+        top: 50%;
+        left: 50%;
+        width: 100%;
+        height: 2px;
+        background: #cc0000;
+        transform: translate(-50%, -50%) rotate(-45deg);
+  }
+}
+
+.color-name {
+    font-size: 0.65rem;
+    color: #444;
+    line-height: 1.1;
+    max-width: 100%;
+    overflow: hidden;
+    text-overflow: ellipsis;
+}
diff --git a/frontend/src/app/shared/components/color-selector/color-selector.component.ts b/frontend/src/app/shared/components/color-selector/color-selector.component.ts
new file mode 100644
index 0000000..cfd8d1a
--- /dev/null
+++ b/frontend/src/app/shared/components/color-selector/color-selector.component.ts
@@ -0,0 +1,40 @@
+import { Component, input, output, signal } from '@angular/core';
+import { CommonModule } from '@angular/common';
+import { TranslateModule } from '@ngx-translate/core';
+import { PRODUCT_COLORS, getColorHex, ColorCategory, ColorOption } from '../../../core/constants/colors.const';
+
+@Component({
+  selector: 'app-color-selector',
+  standalone: true,
+  imports: [CommonModule, TranslateModule],
+  templateUrl: './color-selector.component.html',
+  styleUrl: './color-selector.component.scss'
+})
+export class ColorSelectorComponent {
+  selectedColor = input<string>('Black');
+  colorSelected = output<string>();
+
+  isOpen = signal(false);
+
+  categories: ColorCategory[] = PRODUCT_COLORS;
+
+  toggleOpen() {
+    this.isOpen.update(v => !v);
+  }
+
+  selectColor(color: ColorOption) {
+    if (color.outOfStock) return;
+    
+    this.colorSelected.emit(color.value);
+    this.isOpen.set(false);
+  }
+
+  // Helper to find hex for the current selected value
+  getCurrentHex(): string {
+    return getColorHex(this.selectedColor());
+  }
+
+  close() {
+      this.isOpen.set(false);
+  }
+}
diff --git a/frontend/src/app/shared/components/stl-viewer/stl-viewer.component.ts b/frontend/src/app/shared/components/stl-viewer/stl-viewer.component.ts
index 038c6b8..b9ce5cc 100644
--- a/frontend/src/app/shared/components/stl-viewer/stl-viewer.component.ts
+++ b/frontend/src/app/shared/components/stl-viewer/stl-viewer.component.ts
@@ -15,6 +15,8 @@ import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js';
 })
 export class StlViewerComponent implements OnInit, OnDestroy, OnChanges {
   @Input() file: File | null = null;
+  @Input() color: string = '#facf0a'; // Default Brand Color
+
   @ViewChild('rendererContainer', { static: true }) rendererContainer!: ElementRef;
 
   private scene!: THREE.Scene;
@@ -34,6 +36,12 @@ export class StlViewerComponent implements OnInit, OnDestroy, OnChanges {
     if (changes['file'] && this.file) {
       this.loadFile(this.file);
     }
+    
+    if (changes['color'] && this.currentMesh && !changes['file']) {
+        // Update existing mesh color if only color changed
+        const mat = this.currentMesh.material as THREE.MeshPhongMaterial;
+        mat.color.set(this.color);
+    }
   }
 
   ngOnDestroy() {
@@ -99,7 +107,7 @@ export class StlViewerComponent implements OnInit, OnDestroy, OnChanges {
         }
 
         const material = new THREE.MeshPhongMaterial({ 
-          color: 0xFACF0A, // Brand color
+          color: this.color, 
           specular: 0x111111,
           shininess: 200 
         });