Technical Specification: Interactive ASCII Character Reference Tool

Overview

A high-performance, responsive, single-page web application that provides a searchable, interactive index of the standard ASCII character set (0-127) and extended ASCII range (128-255). This tool is designed for developers, students, and engineers requiring instant lookups of character encoding values.

Core Features

• Live Search & Filtering: Instant-search functionality that updates the table in real-time as the user types (filters by Name, Decimal, Hex, Octal, or Binary).
• Comprehensive Data Display: Table layout showing Decimal, Hex, Octal, Binary, Character, and HTML Entity for every ASCII value.
• Extended Range Toggle: Switch between Standard (0-127) and Extended (128-255) ASCII ranges.
• Interactive Detail View: Clicking a row opens a non-intrusive detail panel showing the specific character information clearly.
• One-Click Copy: Ability to copy the character code or the literal character to the clipboard.

UI/UX Design

• Layout:
  • Header: Sticky header with a prominent search bar and a segment control to toggle between Standard and Extended sets.
  • Main Content: A clean, striped table design or a card-based grid (user-selectable) to view the ASCII list.
  • Detail Modal: A central, lightweight modal for deep-dive information on a selected character.
• Visual Aesthetic:
  • Palette: White backgrounds (#FFFFFF), light gray borders (#E5E7EB), Slate-800 text (#1E293B) for readability, and Primary Blue (#2563EB) for call-to-actions.
  • Typography: Inter or System-sans font stack. Monospace fonts for character and code columns.
  • Animations: Subtle fade-in for search results. Smooth transitions when toggling data ranges. No layout shifts.

Technical Constraints & Requirements

• Architecture: The entire application must be contained in a single .html file.
• Frameworks: Pure Vanilla JavaScript, HTML5, and CSS3 only. No build steps (React/Vue/Angular).
• Sandbox Compatibility:
  • NO LocalStorage: Do not attempt to save user preferences via persistent storage.
  • NO Popups: No alert() or prompt(). All user notifications (e.g., "Copied to clipboard!") must be implemented as non-blocking toasts or UI elements.
• Performance: JavaScript logic must handle the search filtering efficiently in-memory. The entire dataset (256 items) should be pre-loaded as a static JSON object within the script tag.
• Responsive: The table must gracefully collapse columns on small screens, prioritizing the 'Character' and 'Decimal/Hex' values.

Development Guidelines

1. State Management: Use a simple JavaScript object to manage the current view (filtered list vs. full list) and the currently active selection.
2. CDN Usage: Use Tailwind CSS via CDN for styling to maintain a modern SaaS look while keeping file size small.
3. Accessibility: Ensure high contrast ratios and keyboard navigability for the search input and table items.
4. No Dependencies: Avoid heavy external libraries. If icon sets are needed, use a lightweight SVG-based library or inline SVGs.