diff --git a/app/globals.css b/app/globals.css
index bd4a613..453dc28 100644
--- a/app/globals.css
+++ b/app/globals.css
@@ -5,6 +5,7 @@
 :root {
   --background: #fafaf9;
   --foreground: #1c1917;
+  --spinner-accent: #57534e;
 }
 
 @media (prefers-color-scheme: dark) {
@@ -14,6 +15,10 @@
   }
 }
 
+.dark {
+  --spinner-accent: #a8a29e;
+}
+
 body {
   color: var(--foreground);
   background: var(--background);
@@ -368,6 +373,80 @@ h6 {
   animation: chart-live-flash-core-down 1.8s ease-in-out infinite;
 }
 
+/* 3D arc loading spinner */
+.loading-spinner {
+  position: relative;
+  transform-style: preserve-3d;
+  perspective: 800px;
+}
+
+.loading-spinner--sm {
+  width: 2rem;
+  height: 2rem;
+}
+
+.loading-spinner--md {
+  width: 3rem;
+  height: 3rem;
+}
+
+.loading-spinner--lg {
+  width: 4rem;
+  height: 4rem;
+}
+
+.loading-spinner__arc {
+  position: absolute;
+  inset: 0;
+  border-radius: 50%;
+  border-bottom: 3px solid var(--spinner-accent);
+}
+
+.loading-spinner--sm .loading-spinner__arc {
+  border-bottom-width: 2px;
+}
+
+.loading-spinner__arc:nth-child(1) {
+  animation: loading-spinner-rotate-1 1.15s linear infinite;
+  animation-delay: -0.8s;
+}
+
+.loading-spinner__arc:nth-child(2) {
+  animation: loading-spinner-rotate-2 1.15s linear infinite;
+  animation-delay: -0.4s;
+}
+
+.loading-spinner__arc:nth-child(3) {
+  animation: loading-spinner-rotate-3 1.15s linear infinite;
+}
+
+@keyframes loading-spinner-rotate-1 {
+  from {
+    transform: rotateX(35deg) rotateY(-45deg) rotateZ(0);
+  }
+  to {
+    transform: rotateX(35deg) rotateY(-45deg) rotateZ(1turn);
+  }
+}
+
+@keyframes loading-spinner-rotate-2 {
+  from {
+    transform: rotateX(50deg) rotateY(10deg) rotateZ(0);
+  }
+  to {
+    transform: rotateX(50deg) rotateY(10deg) rotateZ(1turn);
+  }
+}
+
+@keyframes loading-spinner-rotate-3 {
+  from {
+    transform: rotateX(35deg) rotateY(55deg) rotateZ(0);
+  }
+  to {
+    transform: rotateX(35deg) rotateY(55deg) rotateZ(1turn);
+  }
+}
+
 @media (prefers-reduced-motion: reduce) {
   .chart-sparkle-sweep--loading,
   .chart-sparkle-flash--loading,
@@ -375,7 +454,8 @@ h6 {
   .chart-scrub-point--active,
   .chart-live-flash-ring,
   .chart-live-flash-core--up,
-  .chart-live-flash-core--down {
+  .chart-live-flash-core--down,
+  .loading-spinner__arc {
     animation: none;
   }
 
diff --git a/components/ChartComponent.tsx b/components/ChartComponent.tsx
index 561b335..ecd3d36 100644
--- a/components/ChartComponent.tsx
+++ b/components/ChartComponent.tsx
@@ -772,7 +772,7 @@ export function ChartComponent({
             className="flex items-center justify-center rounded-xl bg-stone-100/50 dark:bg-stone-900/40"
             style={{ height: `${height}px` }}
           >
-            <LoadingSpinner size="md" message="Updating chart..." />
+            <LoadingSpinner size="md" />
           </div>
         )}
       </div>
diff --git a/components/LoadingSpinner.tsx b/components/LoadingSpinner.tsx
index 8c22260..31efe70 100644
--- a/components/LoadingSpinner.tsx
+++ b/components/LoadingSpinner.tsx
@@ -4,45 +4,53 @@ import { DNA_BODY } from "@/lib/design-dna";
 
 /**
  * LoadingSpinner Component
- * Reusable loading indicator with configurable size and optional message.
- * Supports dark mode via Tailwind CSS classes.
+ * 3D arc spinner with theme-aware accent color via `--spinner-accent`.
  *
  * Requirements: 14.1
  */
 
 export interface LoadingSpinnerProps {
-  /** Spinner size: "sm" (20px), "md" (32px), or "lg" (48px). Defaults to "md". */
+  /** Spinner size: "sm" (32px), "md" (48px), or "lg" (64px). Defaults to "md". */
   size?: "sm" | "md" | "lg";
-  /** Optional message displayed below the spinner */
+  /** Accessible label (screen readers only unless `showMessage` is true). */
   message?: string;
+  /** Show the message visibly below the spinner. Defaults to false. */
+  showMessage?: boolean;
   /** Additional CSS class names */
   className?: string;
 }
 
 const SIZE_CLASSES: Record<NonNullable<LoadingSpinnerProps["size"]>, string> = {
-  sm: "h-5 w-5 border-2",
-  md: "h-8 w-8 border-2",
-  lg: "h-12 w-12 border-[3px]",
+  sm: "loading-spinner--sm",
+  md: "loading-spinner--md",
+  lg: "loading-spinner--lg",
 };
 
 export function LoadingSpinner({
   size = "md",
   message,
+  showMessage = false,
   className = "",
 }: LoadingSpinnerProps) {
+  const label = message ?? "Loading";
+
   return (
     <div
       className={`flex flex-col items-center justify-center ${className}`}
       role="status"
       aria-live="polite"
-      aria-label={message ?? "Loading"}
+      aria-label={label}
       data-testid="loading-spinner"
     >
-      <div
-        className={`animate-spin rounded-full border-stone-700 border-b-transparent dark:border-stone-300 ${SIZE_CLASSES[size]}`}
-      />
-      {message && <p className={`mt-3 ${DNA_BODY}`}>{message}</p>}
-      <span className="sr-only">{message ?? "Loading"}</span>
+      <div className={`loading-spinner ${SIZE_CLASSES[size]}`} aria-hidden>
+        <div className="loading-spinner__arc" />
+        <div className="loading-spinner__arc" />
+        <div className="loading-spinner__arc" />
+      </div>
+      {showMessage && message && (
+        <p className={`mt-3 ${DNA_BODY}`}>{message}</p>
+      )}
+      <span className="sr-only">{label}</span>
     </div>
   );
 }
diff --git a/components/__tests__/ColorContrast.test.tsx b/components/__tests__/ColorContrast.test.tsx
index ceda564..27baff6 100644
--- a/components/__tests__/ColorContrast.test.tsx
+++ b/components/__tests__/ColorContrast.test.tsx
@@ -86,7 +86,7 @@ describe("Color Contrast Compliance (Req 18.3)", () => {
   describe("LoadingSpinner", () => {
     it("uses readable stone text (not text-gray-400) for message text in dark mode", () => {
       const { container } = render(
-        <LoadingSpinner message="Loading data..." />
+        <LoadingSpinner message="Loading data..." showMessage />
       );
       const messageEl = container.querySelector("p");
       expect(messageEl).not.toBeNull();
diff --git a/components/__tests__/LoadingSpinner.test.tsx b/components/__tests__/LoadingSpinner.test.tsx
index cde5fd0..fafad43 100644
--- a/components/__tests__/LoadingSpinner.test.tsx
+++ b/components/__tests__/LoadingSpinner.test.tsx
@@ -24,33 +24,36 @@ describe("LoadingSpinner", () => {
     expect(screen.getByText("Loading")).toBeDefined(); // sr-only text
   });
 
-  it("should display a custom message below the spinner", () => {
+  it("should display a custom message for screen readers only by default", () => {
     render(<LoadingSpinner message="Fetching data..." />);
-    const messages = screen.getAllByText("Fetching data...");
-    expect(messages.length).toBe(2); // visible <p> + sr-only <span>
+    expect(screen.getAllByText("Fetching data...")).toHaveLength(1);
+    expect(screen.queryByRole("paragraph")).toBeNull();
     const spinner = screen.getByTestId("loading-spinner");
     expect(spinner.getAttribute("aria-label")).toBe("Fetching data...");
   });
 
+  it("should show visible message when showMessage is true", () => {
+    render(<LoadingSpinner message="Fetching data..." showMessage />);
+    expect(screen.getAllByText("Fetching data...")).toHaveLength(2);
+  });
+
   it("should render small size variant", () => {
     const { container } = render(<LoadingSpinner size="sm" />);
-    const spinnerCircle = container.querySelector(".animate-spin");
-    expect(spinnerCircle?.classList.contains("h-5")).toBe(true);
-    expect(spinnerCircle?.classList.contains("w-5")).toBe(true);
+    const arcSpinner = container.querySelector(".loading-spinner");
+    expect(arcSpinner?.classList.contains("loading-spinner--sm")).toBe(true);
+    expect(container.querySelectorAll(".loading-spinner__arc")).toHaveLength(3);
   });
 
   it("should render medium size variant (default)", () => {
     const { container } = render(<LoadingSpinner />);
-    const spinnerCircle = container.querySelector(".animate-spin");
-    expect(spinnerCircle?.classList.contains("h-8")).toBe(true);
-    expect(spinnerCircle?.classList.contains("w-8")).toBe(true);
+    const arcSpinner = container.querySelector(".loading-spinner");
+    expect(arcSpinner?.classList.contains("loading-spinner--md")).toBe(true);
   });
 
   it("should render large size variant", () => {
     const { container } = render(<LoadingSpinner size="lg" />);
-    const spinnerCircle = container.querySelector(".animate-spin");
-    expect(spinnerCircle?.classList.contains("h-12")).toBe(true);
-    expect(spinnerCircle?.classList.contains("w-12")).toBe(true);
+    const arcSpinner = container.querySelector(".loading-spinner");
+    expect(arcSpinner?.classList.contains("loading-spinner--lg")).toBe(true);
   });
 
   it("should apply additional className", () => {
@@ -60,7 +63,7 @@ describe("LoadingSpinner", () => {
   });
 
   it("should include sr-only text for screen readers", () => {
-    render(<LoadingSpinner message="Loading chart" />);
+    render(<LoadingSpinner message="Loading chart" showMessage />);
     const srOnly = screen.getByText("Loading chart", {
       selector: ".sr-only",
     });
diff --git a/package.json b/package.json
index 1bfb2c0..c054a62 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "the-open-stock",
-  "version": "0.66.0",
+  "version": "0.67.0",
   "private": true,
   "scripts": {
     "dev": "bun --bun next dev",