diff --git a/app/customize/components/ThemeQuickPresets.empty-fallback.test.tsx b/app/customize/components/ThemeQuickPresets.empty-fallback.test.tsx
new file mode 100644
index 000000000..94117da7d
--- /dev/null
+++ b/app/customize/components/ThemeQuickPresets.empty-fallback.test.tsx
@@ -0,0 +1,67 @@
+import { describe, expect, it, vi } from 'vitest';
+import { render, screen } from '@testing-library/react';
+import '@testing-library/jest-dom/vitest';
+
+import { ThemeQuickPresets } from './ThemeQuickPresets';
+
+describe('ThemeQuickPresets Edge Cases & Empty/Missing Inputs Verification', () => {
+  it('renders successfully with an unknown theme value', () => {
+    expect(() =>
+      render(<ThemeQuickPresets theme="unknown-theme" onThemeChange={vi.fn()} />)
+    ).not.toThrow();
+
+    expect(screen.getAllByRole('button').length).toBeGreaterThan(0);
+  });
+
+  it('renders preset buttons while no active theme matches', () => {
+    render(<ThemeQuickPresets theme="missing-theme" onThemeChange={vi.fn()} />);
+
+    const activeButtons = screen
+      .getAllByRole('button')
+      .filter((button) => button.getAttribute('aria-pressed') === 'true');
+
+    expect(activeButtons).toHaveLength(0);
+  });
+
+  it('maintains default layout structure when active indicators are absent', () => {
+    const { container } = render(
+      <ThemeQuickPresets theme="invalid-theme" onThemeChange={vi.fn()} />
+    );
+
+    const wrapper = container.querySelector('.theme-quick-presets');
+
+    expect(wrapper).toBeInTheDocument();
+    expect(wrapper?.children.length).toBeGreaterThan(0);
+
+    expect(container.querySelector('.tqp-ring')).toBeNull();
+    expect(container.querySelector('.tqp-dot')).toBeNull();
+  });
+
+  it('renders buttons with fallback styling and accessible labels', () => {
+    render(<ThemeQuickPresets theme="not-configured" onThemeChange={vi.fn()} />);
+
+    const buttons = screen.getAllByRole('button');
+
+    expect(buttons.length).toBeGreaterThan(0);
+
+    buttons.forEach((button) => {
+      expect(button).toHaveClass('tqp-btn');
+      expect(button).toHaveAttribute('aria-label');
+      expect(button).toHaveAttribute('style');
+    });
+  });
+
+  it('renders theme preview icons and structural markers without runtime failures', () => {
+    const { container } = render(<ThemeQuickPresets theme="" onThemeChange={vi.fn()} />);
+
+    const svgs = container.querySelectorAll('svg');
+
+    expect(svgs.length).toBeGreaterThan(0);
+
+    svgs.forEach((svg) => {
+      expect(svg).toHaveAttribute('aria-hidden', 'true');
+    });
+
+    expect(container.querySelector('.theme-quick-presets')).toBeInTheDocument();
+  });
+});