Project Development Principles: Reliability & Anti-Regression

To ensure the stability and evolution of the merc1305.github.io project, every agent or developer MUST follow these principles:

1. Respect "Invisible" Features

The project contains many subtle optimizations (mobile paddings, specific margins, visited link colors).

Rule: Never perform large-block replacements in HTML/CSS without first grepping for @media, style=, and :visited.
Action: Use multi_replace_file_content with surgical precision rather than replacing entire sections.

The project serves users on various devices, including mobile.

Rule: Any change to index.css or HTML structure MUST be manually checked against mobile breakpoints (e.g., < 768px).
Checklist:
- Viewport meta tag is present.
- No horizontal scrolling on mobile.
- Tap targets are at least 44x44px.
- Font sizes remain readable (min 16px/1rem for body).

The order of sections in mining-stratum/index.html is intentional.

Rule: Relocating blocks (e.g., moving tutorials to the bottom) should only be done if explicitly requested.
Caution: If refactoring, ensure that informational "help" blocks (tool-intro, tldr) are preserved and correctly styled.

Rule: Before making a change, run git diff HEAD~1 or check recent commit messages to understand what "features" were just added.
Goal: Avoid reverting the previous agent's work.

Rule: NEVER accidentally remove <meta name="viewport" ...> from HTML files. It is the single most critical line for mobile usability.

Failure to follow these rules results in a broken user experience and technical debt.