diff --git a/app/src/components/Warehouse3D.tsx b/app/src/components/Warehouse3D.tsx
index 6c65dca..9ef2156 100644
--- a/app/src/components/Warehouse3D.tsx
+++ b/app/src/components/Warehouse3D.tsx
@@ -5,6 +5,7 @@ import { useGalpaoStore } from '../store/galpaoStore';
 import { useWindStore } from '../store/appStore';
 import SceneCanvas from './SceneCanvas';
 import FallbackDiagram from './FallbackDiagram';
+import { useCanvasTheme } from '../lib/theme';
 
 function pressureColor(cpe: number, cpi: number): THREE.Color {
   const p = cpe - cpi;
@@ -72,6 +73,8 @@ function PressureArrow({
 }
 
 export function WarehouseModel() {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const { width, length, height, roofPitch, wallCpe, roofCpe } = useGalpaoStore();
   const { windAngle, cpi } = useWindStore();
 
@@ -286,17 +289,17 @@ export function WarehouseModel() {
       {/* Cumeeira */}
       <mesh position={[0, height + roofHeight + 0.02, 0]}>
         <boxGeometry args={[0.08, 0.04, length + 0.1]} />
-        <meshStandardMaterial color="#2d3748" roughness={0.5} />
+        <meshStandardMaterial color={isDark ? "#475569" : "#2d3748"} roughness={0.5} />
       </mesh>
 
       {/* Bordas Laterais do Telhado (Beirais) */}
       <mesh position={[width / 2 + 0.02, height, 0]}>
         <boxGeometry args={[0.04, 0.08, length]} />
-        <meshStandardMaterial color="#2d3748" />
+        <meshStandardMaterial color={isDark ? "#475569" : "#2d3748"} />
       </mesh>
       <mesh position={[-width / 2 - 0.02, height, 0]}>
         <boxGeometry args={[0.04, 0.08, length]} />
-        <meshStandardMaterial color="#2d3748" />
+        <meshStandardMaterial color={isDark ? "#475569" : "#2d3748"} />
       </mesh>
 
       {/* === RÓTULOS 3D === */}
@@ -304,7 +307,7 @@ export function WarehouseModel() {
       <Text
         position={[0, height / 2, length / 2 + 1.0]}
         fontSize={Math.max(0.3, Math.min(0.6, width / 20))}
-        color="#1a202c"
+        color={isDark ? "#cbd5e1" : "#1a202c"}
         anchorX="center"
         anchorY="middle"
       >
@@ -316,7 +319,7 @@ export function WarehouseModel() {
         position={[0, height / 2, -length / 2 - 1.0]}
         rotation={[0, Math.PI, 0]}
         fontSize={Math.max(0.3, Math.min(0.6, width / 20))}
-        color="#1a202c"
+        color={isDark ? "#cbd5e1" : "#1a202c"}
         anchorX="center"
         anchorY="middle"
       >
@@ -328,7 +331,7 @@ export function WarehouseModel() {
         position={[-width / 2 - 1.0, height / 2, 0]}
         rotation={[0, -Math.PI / 2, 0]}
         fontSize={Math.max(0.3, Math.min(0.6, length / 20))}
-        color="#1a202c"
+        color={isDark ? "#cbd5e1" : "#1a202c"}
         anchorX="center"
         anchorY="middle"
       >
@@ -340,7 +343,7 @@ export function WarehouseModel() {
         position={[width / 2 + 1.0, height / 2, 0]}
         rotation={[0, Math.PI / 2, 0]}
         fontSize={Math.max(0.3, Math.min(0.6, length / 20))}
-        color="#1a202c"
+        color={isDark ? "#cbd5e1" : "#1a202c"}
         anchorX="center"
         anchorY="middle"
       >
@@ -351,6 +354,8 @@ export function WarehouseModel() {
 }
 
 export default function Warehouse3DViewer() {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const { width, length, height, roofPitch, wallCpe, roofCpe } = useGalpaoStore();
   const { windAngle, cpi } = useWindStore();
 
@@ -384,7 +389,13 @@ export default function Warehouse3DViewer() {
         shadow-camera-bottom={-maxDimension}
       />
       <WarehouseModel />
-      <Grid infiniteGrid fadeDistance={maxDimension * 5} sectionColor="#94a3b8" cellColor="#cbd5e1" position={[0, -0.01, 0]} />
+      <Grid 
+        infiniteGrid 
+        fadeDistance={maxDimension * 5} 
+        sectionColor={isDark ? "#475569" : "#94a3b8"} 
+        cellColor={isDark ? "#1e293b" : "#cbd5e1"} 
+        position={[0, -0.01, 0]} 
+      />
       <OrbitControls makeDefault minPolarAngle={0} maxPolarAngle={Math.PI / 2 - 0.05} />
       <Environment preset="city" />
     </SceneCanvas>
diff --git a/app/src/components/three/Bar3D.tsx b/app/src/components/three/Bar3D.tsx
index 96bf9ff..930a67e 100644
--- a/app/src/components/three/Bar3D.tsx
+++ b/app/src/components/three/Bar3D.tsx
@@ -3,6 +3,7 @@ import { OrbitControls, Grid, Environment, Text } from '@react-three/drei';
 import * as THREE from 'three';
 import SceneCanvas from '../SceneCanvas';
 import FallbackDiagram from '../FallbackDiagram';
+import { useCanvasTheme } from '@/lib/theme';
 
 export interface Bar3DInput {
   /** Tipo de seção */
@@ -34,14 +35,18 @@ function BarModel({
   alpha,
   cx,
 }: Bar3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
+  
   const barRadius = barType === 'circular' ? (diameter ?? 0.05) / 2 : Math.min(width ?? 0.1, 0.08) / 2;
   const barThickness = barType === 'circular' ? barRadius : barRadius * 0.5;
 
   const barColor = useMemo(() => {
     const intensity = Math.min(1, Math.abs(cx) / 2.5);
     const hue = 215 - intensity * 215;
-    return new THREE.Color(`hsl(${hue}, ${65 + intensity * 25}%, ${45 - intensity * 10}%)`);
-  }, [cx]);
+    const l = isDark ? (55 - intensity * 10) : (45 - intensity * 10);
+    return new THREE.Color(`hsl(${hue}, ${65 + intensity * 25}%, ${l}%)`);
+  }, [cx, isDark]);
 
   // Ação do vento deve rotacionar a barra em seu próprio eixo longitudinal (roll).
   // O eixo longitudinal na nossa geometria é o X.
@@ -87,7 +92,7 @@ function BarModel({
       <Text
         position={[0, -barRadius * 2 - 0.4, 0]}
         fontSize={0.3}
-        color="#1e40af"
+        color={isDark ? "#93c5fd" : "#1e40af"}
         anchorX="center"
         anchorY="top"
       >
@@ -172,6 +177,8 @@ function SectionShape({
 }
 
 export default function Bar3DViewer(input: Bar3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const { length, width, diameter } = input;
   const size = Math.max(length * 0.6, (width ?? diameter ?? 0.1) * 8);
 
@@ -192,7 +199,13 @@ export default function Bar3DViewer(input: Bar3DInput) {
       <ambientLight intensity={0.6} />
       <directionalLight position={[size, size, size]} intensity={1.2} castShadow shadow-mapSize-width={1024} shadow-mapSize-height={1024} />
       <BarModel {...input} />
-      <Grid infiniteGrid fadeDistance={size * 2} sectionColor="#94a3b8" cellColor="#cbd5e1" position={[0, -size * 0.3, 0]} />
+      <Grid 
+        infiniteGrid 
+        fadeDistance={size * 2} 
+        sectionColor={isDark ? "#475569" : "#94a3b8"} 
+        cellColor={isDark ? "#1e293b" : "#cbd5e1"} 
+        position={[0, -size * 0.3, 0]} 
+      />
       <OrbitControls makeDefault minPolarAngle={0} maxPolarAngle={Math.PI - 0.05} />
       <Environment preset="city" />
     </SceneCanvas>
diff --git a/app/src/components/three/Bridge3D.tsx b/app/src/components/three/Bridge3D.tsx
index a566a4b..08a4371 100644
--- a/app/src/components/three/Bridge3D.tsx
+++ b/app/src/components/three/Bridge3D.tsx
@@ -4,6 +4,7 @@ import * as THREE from 'three';
 import SceneCanvas from '../SceneCanvas';
 import FallbackDiagram from '../FallbackDiagram';
 import { WindArrow } from './WindArrow';
+import { useCanvasTheme } from '@/lib/theme';
 
 export interface Bridge3DInput {
   /** Maior vão Lₚ (m) */
@@ -34,6 +35,9 @@ function BridgeModel({
   cx,
   alpha,
 }: Bridge3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
+  
   const halfL = lp / 2;
   const halfW = width / 2;
   const deckThickness = Math.max(heg, 0.8);
@@ -43,11 +47,14 @@ function BridgeModel({
   const deckColor = useMemo(() => {
     const intensity = Math.min(1, Math.abs(cx) / 3);
     const hue = 200 - intensity * 60;
-    return new THREE.Color(`hsl(${hue}, ${55 + intensity * 30}%, ${50 - intensity * 8}%)`);
-  }, [cx]);
+    const l = isDark ? (60 - intensity * 8) : (50 - intensity * 8);
+    return new THREE.Color(`hsl(${hue}, ${55 + intensity * 30}%, ${l}%)`);
+  }, [cx, isDark]);
 
   // Pilar heights: posicionar 3 pilares ao longo do vão
   const pillarHeights = useMemo(() => [deckY - 0.5, deckY - 0.5, deckY - 0.5], [deckY]);
+  const barrierColor = isDark ? '#cbd5e1' : '#94a3b8';
+  const pillarColor = isDark ? '#94a3b8' : '#64748b';
 
   return (
     <group>
@@ -60,11 +67,11 @@ function BridgeModel({
       {/* Guarda-rodas/barreira lateral */}
       <mesh position={[0, deckY + deckThickness / 2 + 0.3, halfW - 0.15]} castShadow>
         <boxGeometry args={[lp, 0.5, 0.1]} />
-        <meshStandardMaterial color="#94a3b8" roughness={0.7} />
+        <meshStandardMaterial color={barrierColor} roughness={0.7} />
       </mesh>
       <mesh position={[0, deckY + deckThickness / 2 + 0.3, -halfW + 0.15]} castShadow>
         <boxGeometry args={[lp, 0.5, 0.1]} />
-        <meshStandardMaterial color="#94a3b8" roughness={0.7} />
+        <meshStandardMaterial color={barrierColor} roughness={0.7} />
       </mesh>
 
       {/* Pilares (3 ao longo do comprimento) */}
@@ -73,7 +80,7 @@ function BridgeModel({
         return (
           <mesh key={`pillar-${i}`} position={[x, h / 2, 0]} castShadow receiveShadow>
             <boxGeometry args={[1.5, h, 1.5]} />
-            <meshStandardMaterial color="#64748b" roughness={0.7} />
+            <meshStandardMaterial color={pillarColor} roughness={0.7} />
           </mesh>
         );
       })}
@@ -93,7 +100,7 @@ function BridgeModel({
       <Text
         position={[0, deckY + deckThickness + 1.5, 0]}
         fontSize={1.2}
-        color="#1e40af"
+        color={isDark ? "#93c5fd" : "#1e40af"}
         anchorX="center"
         anchorY="bottom"
       >
@@ -103,9 +110,9 @@ function BridgeModel({
   );
 }
 
-
-
 export default function Bridge3DViewer(input: Bridge3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const { lp, deckHeight, width } = input;
   const dist = Math.max(lp * 0.6, deckHeight * 2);
 
@@ -126,7 +133,13 @@ export default function Bridge3DViewer(input: Bridge3DInput) {
       <ambientLight intensity={0.6} />
       <directionalLight position={[lp, deckHeight * 3, width * 3]} intensity={1.2} castShadow shadow-mapSize-width={1024} shadow-mapSize-height={1024} />
       <BridgeModel {...input} />
-      <Grid infiniteGrid fadeDistance={lp * 0.5} sectionColor="#94a3b8" cellColor="#cbd5e1" position={[0, -0.01, 0]} />
+      <Grid 
+        infiniteGrid 
+        fadeDistance={lp * 0.5} 
+        sectionColor={isDark ? "#475569" : "#94a3b8"} 
+        cellColor={isDark ? "#1e293b" : "#cbd5e1"} 
+        position={[0, -0.01, 0]} 
+      />
       <OrbitControls makeDefault minPolarAngle={0} maxPolarAngle={Math.PI / 2 - 0.05} />
       <Environment preset="city" />
     </SceneCanvas>
diff --git a/app/src/components/three/Cylinder3D.tsx b/app/src/components/three/Cylinder3D.tsx
index ce882c4..cc8b5b6 100644
--- a/app/src/components/three/Cylinder3D.tsx
+++ b/app/src/components/three/Cylinder3D.tsx
@@ -3,6 +3,7 @@ import { OrbitControls, Grid, Environment, Text } from '@react-three/drei';
 import * as THREE from 'three';
 import SceneCanvas from '../SceneCanvas';
 import FallbackDiagram from '../FallbackDiagram';
+import { useCanvasTheme } from '@/lib/theme';
 
 export interface Cylinder3DInput {
   diameter: number;
@@ -22,6 +23,8 @@ function cylinderColor(cpe: number, cpi: number): THREE.Color {
 }
 
 function CylinderModel({ diameter, height, cpeProfile, cpi }: Cylinder3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const segments = 64;
   const radius = diameter / 2;
 
@@ -121,11 +124,11 @@ function CylinderModel({ diameter, height, cpeProfile, cpi }: Cylinder3DInput) {
       {/* Anéis de detalhe (bordas do cilindro) */}
       <mesh position={[0, height + 0.01, 0]} rotation={[-Math.PI / 2, 0, 0]}>
         <ringGeometry args={[radius - 0.03, radius + 0.03, segments]} />
-        <meshStandardMaterial color="#2d3748" roughness={0.5} />
+        <meshStandardMaterial color={isDark ? "#475569" : "#2d3748"} roughness={0.5} />
       </mesh>
       <mesh position={[0, 0.01, 0]} rotation={[-Math.PI / 2, 0, 0]}>
         <ringGeometry args={[radius - 0.03, radius + 0.03, segments]} />
-        <meshStandardMaterial color="#2d3748" roughness={0.5} />
+        <meshStandardMaterial color={isDark ? "#475569" : "#2d3748"} roughness={0.5} />
       </mesh>
 
       {/* Seta indicativa de direção do vento */}
@@ -154,7 +157,7 @@ function CylinderModel({ diameter, height, cpeProfile, cpi }: Cylinder3DInput) {
       <Text
         position={[0, height + 0.8, 0]}
         fontSize={Math.max(0.3, Math.min(0.6, diameter / 10))}
-        color="#1a202c"
+        color={isDark ? "#cbd5e1" : "#1a202c"}
         anchorX="center"
         anchorY="bottom"
       >
@@ -165,6 +168,9 @@ function CylinderModel({ diameter, height, cpeProfile, cpi }: Cylinder3DInput) {
 }
 
 export default function Cylinder3DViewer({ diameter, height, cpeProfile, cpi }: Cylinder3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
+
   const fallback = (
     <FallbackDiagram
       type="cylinder"
@@ -195,7 +201,13 @@ export default function Cylinder3DViewer({ diameter, height, cpeProfile, cpi }:
         shadow-camera-bottom={-maxDim}
       />
       <CylinderModel diameter={diameter} height={height} cpeProfile={cpeProfile} cpi={cpi} />
-      <Grid infiniteGrid fadeDistance={maxDim * 5} sectionColor="#94a3b8" cellColor="#cbd5e1" position={[0, -0.01, 0]} />
+      <Grid 
+        infiniteGrid 
+        fadeDistance={maxDim * 5} 
+        sectionColor={isDark ? "#475569" : "#94a3b8"} 
+        cellColor={isDark ? "#1e293b" : "#cbd5e1"} 
+        position={[0, -0.01, 0]} 
+      />
       <OrbitControls makeDefault minPolarAngle={0} maxPolarAngle={Math.PI / 2 - 0.05} />
       <Environment preset="city" />
     </SceneCanvas>
diff --git a/app/src/components/three/Dome3D.tsx b/app/src/components/three/Dome3D.tsx
index 55cb9ef..e866ae1 100644
--- a/app/src/components/three/Dome3D.tsx
+++ b/app/src/components/three/Dome3D.tsx
@@ -3,6 +3,7 @@ import { OrbitControls, Grid, Environment, Text } from '@react-three/drei';
 import * as THREE from 'three';
 import SceneCanvas from '../SceneCanvas';
 import FallbackDiagram from '../FallbackDiagram';
+import { useCanvasTheme } from '@/lib/theme';
 
 export interface Dome3DInput {
   diameter: number;
@@ -14,16 +15,19 @@ export interface Dome3DInput {
   cpeLateral: number;
 }
 
-function domeColor(cpe: number, cpi: number): THREE.Color {
+function domeColor(cpe: number, cpi: number, isDark: boolean): THREE.Color {
   const p = cpe - cpi;
   const intensity = Math.min(1, Math.abs(p) / 1.5);
+  const l = isDark ? (65 - intensity * 15) : (60 - intensity * 25);
   if (p > 0) {
-    return new THREE.Color(`hsl(${215 - intensity * 10}, ${70 + intensity * 25}%, ${Math.max(35, 60 - intensity * 25)}%)`);
+    return new THREE.Color(`hsl(${215 - intensity * 10}, ${70 + intensity * 25}%, ${Math.max(35, l)}%)`);
   }
-  return new THREE.Color(`hsl(0, ${70 + intensity * 25}%, ${Math.max(40, 60 - intensity * 20)}%)`);
+  return new THREE.Color(`hsl(0, ${70 + intensity * 25}%, ${Math.max(40, l + 5)}%)`);
 }
 
 function DomeModel({ diameter, rise, wallHeight, cpi, cpeBarlavento, cpeTopo, cpeLateral }: Dome3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const radius = diameter / 2;
   const segments = 64;
 
@@ -31,12 +35,6 @@ function DomeModel({ diameter, rise, wallHeight, cpi, cpeBarlavento, cpeTopo, cp
   const domeGeoms = useMemo(() => {
     const arr: { startTheta: number; endTheta: number; color: THREE.Color }[] = [];
     // Divide a circunferência completa (360°) em 6 zonas (simétricas)
-    // 0° a 60°: Barlavento
-    // 60° a 120°: Topo
-    // 120° a 180°: Lateral
-    // 180° a 240°: Lateral (espelhado)
-    // 240° a 300°: Topo (espelhado)
-    // 300° a 360°: Barlavento (espelhado)
     const zones = [
       { fromDeg: 0, toDeg: 60, cpe: cpeBarlavento },
       { fromDeg: 60, toDeg: 120, cpe: cpeTopo },
@@ -49,11 +47,11 @@ function DomeModel({ diameter, rise, wallHeight, cpi, cpeBarlavento, cpeTopo, cp
       arr.push({
         startTheta: (z.fromDeg * Math.PI) / 180,
         endTheta: (z.toDeg * Math.PI) / 180,
-        color: domeColor(z.cpe, cpi),
+        color: domeColor(z.cpe, cpi, isDark),
       });
     }
     return arr;
-  }, [cpeBarlavento, cpeTopo, cpeLateral, cpi]);
+  }, [cpeBarlavento, cpeTopo, cpeLateral, cpi, isDark]);
 
   // Raio da esfera da calota esférica baseada na flecha (rise) e raio da base (radius)
   const rSphere = useMemo(() => {
@@ -71,11 +69,11 @@ function DomeModel({ diameter, rise, wallHeight, cpi, cpeBarlavento, cpeTopo, cp
       {/* Detalhes de anéis metálicos nas bordas */}
       <mesh position={[0, 0.01, 0]} rotation={[-Math.PI / 2, 0, 0]}>
         <ringGeometry args={[radius - 0.03, radius + 0.03, segments]} />
-        <meshStandardMaterial color="#2d3748" roughness={0.5} />
+        <meshStandardMaterial color={isDark ? "#475569" : "#2d3748"} roughness={0.5} />
       </mesh>
       <mesh position={[0, wallHeight, 0]} rotation={[-Math.PI / 2, 0, 0]}>
         <ringGeometry args={[radius - 0.03, radius + 0.03, segments]} />
-        <meshStandardMaterial color="#2d3748" roughness={0.5} />
+        <meshStandardMaterial color={isDark ? "#475569" : "#2d3748"} roughness={0.5} />
       </mesh>
 
       {/* Cúpula de cobertura (Spherical Cap) segmentada */}
@@ -156,7 +154,7 @@ function DomeModel({ diameter, rise, wallHeight, cpi, cpeBarlavento, cpeTopo, cp
       <Text
         position={[0, wallHeight + rise + 0.8, 0]}
         fontSize={Math.max(0.3, Math.min(0.6, diameter / 12))}
-        color="#1a202c"
+        color={isDark ? "#cbd5e1" : "#1a202c"}
         anchorX="center"
         anchorY="bottom"
       >
@@ -167,6 +165,9 @@ function DomeModel({ diameter, rise, wallHeight, cpi, cpeBarlavento, cpeTopo, cp
 }
 
 export default function Dome3DViewer(props: Dome3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
+
   const fallback = (
     <FallbackDiagram
       type="dome"
@@ -197,7 +198,13 @@ export default function Dome3DViewer(props: Dome3DInput) {
         shadow-camera-bottom={-maxDim}
       />
       <DomeModel {...props} />
-      <Grid infiniteGrid fadeDistance={maxDim * 5} sectionColor="#94a3b8" cellColor="#cbd5e1" position={[0, -0.01, 0]} />
+      <Grid 
+        infiniteGrid 
+        fadeDistance={maxDim * 5} 
+        sectionColor={isDark ? "#475569" : "#94a3b8"} 
+        cellColor={isDark ? "#1e293b" : "#cbd5e1"} 
+        position={[0, -0.01, 0]} 
+      />
       <OrbitControls makeDefault minPolarAngle={0} maxPolarAngle={Math.PI / 2 - 0.05} />
       <Environment preset="city" />
     </SceneCanvas>
diff --git a/app/src/components/three/Dynamics3D.tsx b/app/src/components/three/Dynamics3D.tsx
index e2f75bc..52dc4e1 100644
--- a/app/src/components/three/Dynamics3D.tsx
+++ b/app/src/components/three/Dynamics3D.tsx
@@ -4,6 +4,7 @@ import { OrbitControls, Grid, Environment, Text } from '@react-three/drei';
 import * as THREE from 'three';
 import SceneCanvas from '../SceneCanvas';
 import FallbackDiagram from '../FallbackDiagram';
+import { useCanvasTheme } from '@/lib/theme';
 
 export interface Dynamics3DInput {
   /** Altura da estrutura (m) */
@@ -138,11 +139,13 @@ function VortexStreet({
 }
 
 function DynamicsModel(props: Dynamics3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   return (
     <group>
       <mesh rotation={[-Math.PI / 2, 0, 0]} position={[0, -0.01, 0]} receiveShadow>
         <planeGeometry args={[20, 20]} />
-        <meshStandardMaterial color="#94a3b8" transparent opacity={0.15} />
+        <meshStandardMaterial color={isDark ? "#1e293b" : "#94a3b8"} transparent opacity={0.15} />
       </mesh>
 
       <OscillatingBuilding
@@ -164,7 +167,7 @@ function DynamicsModel(props: Dynamics3DInput) {
       <Text
         position={[0, props.height * SCALE + 0.8, 0]}
         fontSize={0.5}
-        color="#1e40af"
+        color={isDark ? "#93c5fd" : "#1e40af"}
         anchorX="center"
         anchorY="bottom"
       >
@@ -175,6 +178,8 @@ function DynamicsModel(props: Dynamics3DInput) {
 }
 
 export default function Dynamics3DViewer(props: Dynamics3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const cameraDistance = Math.max(props.height * SCALE * 2, 6);
 
   const fallback = (
@@ -201,7 +206,13 @@ export default function Dynamics3DViewer(props: Dynamics3DInput) {
         shadow-mapSize-height={1024}
       />
       <DynamicsModel {...props} />
-      <Grid infiniteGrid fadeDistance={50} sectionColor="#94a3b8" cellColor="#cbd5e1" position={[0, -0.01, 0]} />
+      <Grid 
+        infiniteGrid 
+        fadeDistance={50} 
+        sectionColor={isDark ? "#475569" : "#94a3b8"} 
+        cellColor={isDark ? "#1e293b" : "#cbd5e1"} 
+        position={[0, -0.01, 0]} 
+      />
       <OrbitControls makeDefault minPolarAngle={0} maxPolarAngle={Math.PI / 2 - 0.05} />
       <Environment preset="city" />
     </SceneCanvas>
diff --git a/app/src/components/three/Sign3D.tsx b/app/src/components/three/Sign3D.tsx
index 79bbb4c..6b449ce 100644
--- a/app/src/components/three/Sign3D.tsx
+++ b/app/src/components/three/Sign3D.tsx
@@ -4,6 +4,7 @@ import * as THREE from 'three';
 import SceneCanvas from '../SceneCanvas';
 import FallbackDiagram from '../FallbackDiagram';
 import { WindArrow } from './WindArrow';
+import { useCanvasTheme } from '@/lib/theme';
 
 export interface Sign3DInput {
   /** Comprimento ℓ (m) */
@@ -34,6 +35,8 @@ function SignModel({
   cf,
   applicationPoint,
 }: Sign3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const baseY = groundClearance;
   const topY = baseY + height;
   const halfL = length / 2;
@@ -72,11 +75,11 @@ function SignModel({
         <>
           <mesh position={[0, (baseY + topY) / 2, halfL]} castShadow>
             <boxGeometry args={[0.3, height * 0.95, 0.04]} />
-            <meshStandardMaterial color="#64748b" opacity={0.6} transparent side={THREE.DoubleSide} />
+            <meshStandardMaterial color={isDark ? "#475569" : "#64748b"} opacity={0.6} transparent side={THREE.DoubleSide} />
           </mesh>
           <mesh position={[0, (baseY + topY) / 2, -halfL]} castShadow>
             <boxGeometry args={[0.3, height * 0.95, 0.04]} />
-            <meshStandardMaterial color="#64748b" opacity={0.6} transparent side={THREE.DoubleSide} />
+            <meshStandardMaterial color={isDark ? "#475569" : "#64748b"} opacity={0.6} transparent side={THREE.DoubleSide} />
           </mesh>
         </>
       )}
@@ -84,13 +87,13 @@ function SignModel({
       {/* Linha do solo (base translúcida) */}
       <mesh position={[0, 0, 0]} rotation={[-Math.PI / 2, 0, 0]} receiveShadow>
         <planeGeometry args={[length * 1.5, length * 1.5]} />
-        <meshStandardMaterial color="#94a3b8" opacity={0.15} transparent />
+        <meshStandardMaterial color={isDark ? "#1e293b" : "#94a3b8"} opacity={0.15} transparent />
       </mesh>
 
       {/* Eixo horizontal de referência de direção do vento */}
       <mesh position={[0, 0.005, 0]} rotation={[-Math.PI / 2, 0, 0]}>
         <planeGeometry args={[length * 1.5, 0.03]} />
-        <meshStandardMaterial color="#475569" opacity={0.5} transparent />
+        <meshStandardMaterial color={isDark ? "#334155" : "#475569"} opacity={0.5} transparent />
       </mesh>
 
       {/* Marca da excentricidade (Ponto de Aplicação da Resultante) */}
@@ -104,7 +107,7 @@ function SignModel({
         position={[0.2, (baseY + topY) / 2, applicationPoint]}
         rotation={[0, Math.PI / 2, 0]}
         fontSize={0.15}
-        color="#d97706"
+        color={isDark ? "#fcd34d" : "#d97706"}
         anchorX="left"
         anchorY="middle"
       >
@@ -123,24 +126,24 @@ function SignModel({
         {/* Linha vertical */}
         <mesh position={[0, (baseY + topY) / 2, 0]}>
           <boxGeometry args={[0.015, height, 0.015]} />
-          <meshStandardMaterial color="#64748b" />
+          <meshStandardMaterial color={isDark ? "#475569" : "#64748b"} />
         </mesh>
         {/* Traço superior */}
         <mesh position={[0, topY, 0]}>
           <boxGeometry args={[0.1, 0.015, 0.015]} />
-          <meshStandardMaterial color="#64748b" />
+          <meshStandardMaterial color={isDark ? "#475569" : "#64748b"} />
         </mesh>
         {/* Traço inferior */}
         <mesh position={[0, baseY, 0]}>
           <boxGeometry args={[0.1, 0.015, 0.015]} />
-          <meshStandardMaterial color="#64748b" />
+          <meshStandardMaterial color={isDark ? "#475569" : "#64748b"} />
         </mesh>
         {/* Texto da altura */}
         <Text
           position={[-0.15, (baseY + topY) / 2, 0]}
           rotation={[0, -Math.PI / 2, 0]}
           fontSize={0.25}
-          color="#475569"
+          color={isDark ? "#94a3b8" : "#475569"}
           anchorX="center"
           anchorY="middle"
         >
@@ -153,24 +156,24 @@ function SignModel({
         {/* Linha horizontal longitudinal */}
         <mesh position={[0, 0, 0]}>
           <boxGeometry args={[0.015, 0.015, length]} />
-          <meshStandardMaterial color="#64748b" />
+          <meshStandardMaterial color={isDark ? "#475569" : "#64748b"} />
         </mesh>
         {/* Traço frontal */}
         <mesh position={[0, 0, halfL]}>
           <boxGeometry args={[0.1, 0.015, 0.015]} />
-          <meshStandardMaterial color="#64748b" />
+          <meshStandardMaterial color={isDark ? "#475569" : "#64748b"} />
         </mesh>
         {/* Traço traseiro */}
         <mesh position={[0, 0, -halfL]}>
           <boxGeometry args={[0.1, 0.015, 0.015]} />
-          <meshStandardMaterial color="#64748b" />
+          <meshStandardMaterial color={isDark ? "#475569" : "#64748b"} />
         </mesh>
         {/* Texto do comprimento */}
         <Text
           position={[-0.15, 0, 0]}
           rotation={[0, -Math.PI / 2, 0]}
           fontSize={0.25}
-          color="#475569"
+          color={isDark ? "#94a3b8" : "#475569"}
           anchorX="center"
           anchorY="middle"
         >
@@ -182,7 +185,7 @@ function SignModel({
       <Text
         position={[0, topY + 0.6, 0]}
         fontSize={0.4}
-        color="#1a202c"
+        color={isDark ? "#cbd5e1" : "#1a202c"}
         anchorX="center"
         anchorY="bottom"
       >
@@ -203,6 +206,9 @@ export default function Sign3DViewer({
   forceKN,
   applicationPoint,
 }: Sign3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
+
   const fallback = (
     <FallbackDiagram
       type="sign"
@@ -230,7 +236,13 @@ export default function Sign3DViewer({
         forceKN={forceKN}
         applicationPoint={applicationPoint}
       />
-      <Grid infiniteGrid fadeDistance={maxDim * 5} sectionColor="#94a3b8" cellColor="#cbd5e1" position={[0, -0.01, 0]} />
+      <Grid 
+        infiniteGrid 
+        fadeDistance={maxDim * 5} 
+        sectionColor={isDark ? "#475569" : "#94a3b8"} 
+        cellColor={isDark ? "#1e293b" : "#cbd5e1"} 
+        position={[0, -0.01, 0]} 
+      />
       <OrbitControls makeDefault minPolarAngle={0} maxPolarAngle={Math.PI / 2 - 0.05} />
       <Environment preset="city" />
     </SceneCanvas>
diff --git a/app/src/components/three/Vault3D.tsx b/app/src/components/three/Vault3D.tsx
index 14612b4..dab7a86 100644
--- a/app/src/components/three/Vault3D.tsx
+++ b/app/src/components/three/Vault3D.tsx
@@ -3,6 +3,7 @@ import { OrbitControls, Grid, Environment, Text } from '@react-three/drei';
 import * as THREE from 'three';
 import SceneCanvas from '../SceneCanvas';
 import FallbackDiagram from '../FallbackDiagram';
+import { useCanvasTheme } from '@/lib/theme';
 
 export interface Vault3DInput {
   span: number;
@@ -12,16 +13,19 @@ export interface Vault3DInput {
   cpeProfile: Record<string, number>;
 }
 
-function vaultColor(cpe: number, cpi: number): THREE.Color {
+function vaultColor(cpe: number, cpi: number, isDark: boolean): THREE.Color {
   const p = cpe - cpi;
   const intensity = Math.min(1, Math.abs(p) / 1.5);
+  const l = isDark ? (65 - intensity * 15) : (60 - intensity * 25);
   if (p > 0) {
-    return new THREE.Color(`hsl(${215 - intensity * 10}, ${70 + intensity * 25}%, ${Math.max(35, 60 - intensity * 25)}%)`);
+    return new THREE.Color(`hsl(${215 - intensity * 10}, ${70 + intensity * 25}%, ${Math.max(35, l)}%)`);
   }
-  return new THREE.Color(`hsl(0, ${70 + intensity * 25}%, ${Math.max(40, 60 - intensity * 20)}%)`);
+  return new THREE.Color(`hsl(0, ${70 + intensity * 25}%, ${Math.max(40, l + 5)}%)`);
 }
 
 function VaultModel({ span, length, rise, cpi, cpeProfile }: Vault3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
   const segments = 64;
   const points = useMemo(() => {
     const pts: THREE.Vector3[] = [];
@@ -66,7 +70,7 @@ function VaultModel({ span, length, rise, cpi, cpeProfile }: Vault3DInput) {
     <group>
       {/* Casca da Abóbada */}
       {zones.map((zone, idx) => {
-        const color = vaultColor(zone.cpe, cpi);
+        const color = vaultColor(zone.cpe, cpi, isDark);
         const verts: number[] = [];
         for (let i = zone.startIdx; i <= zone.endIdx; i++) {
           verts.push(points[i].x, points[i].y, points[i].z);
@@ -94,20 +98,20 @@ function VaultModel({ span, length, rise, cpi, cpeProfile }: Vault3DInput) {
       {/* Tímpano Traseiro (Z = 0) */}
       <mesh position={[0, 0, 0]} castShadow receiveShadow>
         <shapeGeometry args={[archShape]} />
-        <meshStandardMaterial color="#cbd5e1" opacity={0.7} transparent side={THREE.DoubleSide} roughness={0.5} />
+        <meshStandardMaterial color={isDark ? "#334155" : "#cbd5e1"} opacity={0.7} transparent side={THREE.DoubleSide} roughness={0.5} />
       </mesh>
 
       {/* Tímpano Frontal (Z = length) */}
       <mesh position={[0, 0, length]} castShadow receiveShadow>
         <shapeGeometry args={[archShape]} />
-        <meshStandardMaterial color="#cbd5e1" opacity={0.7} transparent side={THREE.DoubleSide} roughness={0.5} />
+        <meshStandardMaterial color={isDark ? "#334155" : "#cbd5e1"} opacity={0.7} transparent side={THREE.DoubleSide} roughness={0.5} />
       </mesh>
 
       {/* Rótulo de dimensões */}
       <Text
         position={[0, rise + 0.6, length / 2]}
         fontSize={Math.max(0.3, Math.min(0.6, span / 20))}
-        color="#1a202c"
+        color={isDark ? "#cbd5e1" : "#1a202c"}
         anchorX="center"
         anchorY="bottom"
       >
@@ -118,6 +122,9 @@ function VaultModel({ span, length, rise, cpi, cpeProfile }: Vault3DInput) {
 }
 
 export default function Vault3DViewer({ span, length, rise, cpi, cpeProfile }: Vault3DInput) {
+  const theme = useCanvasTheme();
+  const isDark = theme === 'dark';
+
   const fallback = (
     <FallbackDiagram
       type="vault"
@@ -143,7 +150,13 @@ export default function Vault3DViewer({ span, length, rise, cpi, cpeProfile }: V
         shadow-mapSize-height={1024}
       />
       <VaultModel span={span} length={length} rise={rise} cpi={cpi} cpeProfile={cpeProfile} />
-      <Grid infiniteGrid fadeDistance={maxDimension * 5} sectionColor="#94a3b8" cellColor="#cbd5e1" position={[0, -0.01, 0]} />
+      <Grid 
+        infiniteGrid 
+        fadeDistance={maxDimension * 5} 
+        sectionColor={isDark ? "#475569" : "#94a3b8"} 
+        cellColor={isDark ? "#1e293b" : "#cbd5e1"} 
+        position={[0, -0.01, 0]} 
+      />
       <OrbitControls makeDefault minPolarAngle={0} maxPolarAngle={Math.PI / 2 - 0.05} />
       <Environment preset="city" />
     </SceneCanvas>