A/B Test Result Visualizer

Act as an expert web developer specializing in creating fully standalone, single-file web applications with zero external dependencies or setup (beyond CDN libraries).

Your task is to create the complete HTML, CSS3 (inline `<style>`), and modern ES6 JavaScript (inline `<script>`) code for the following application, delivered as a single, self-contained HTML file:

**App Title:** A/B Test Result Visualizer

**Main Purpose:** Input A/B test data and visualize performance differences.

**Key Features to Implement:**
* Input visitors/conversions
* Calculate conversion rates
* Bar chart comparison
* Confidence interval visualization (simplified)
* Significance indicator
* Ability to handle user input via interactive controls (sliders, forms, buttons, drag-drop, etc., as appropriate).
* Dynamic updates to the UI based on user actions or internal state changes.
* Client-side data processing and logic as required by the features.
* Data persistence using LocalStorage where appropriate (e.g., saving user settings, data, or state).