# Page Not Found

The URL `introduccion/core.css` does not exist. This page may have been moved, renamed, or deleted.

## Suggested Pages

You may be looking for one of the following:
- [Introducción](https://ajgallego.gitbook.io/bootstrap-4/introduccion.md)
- [Frameworks responsive](https://ajgallego.gitbook.io/bootstrap-4/introduccion/introduccion-frameworks.md)
- [Probando el responsive](https://ajgallego.gitbook.io/bootstrap-4/introduccion/introduccion-pruebas.md)
- [Funcionamiento del diseño adaptable](https://ajgallego.gitbook.io/bootstrap-4/introduccion/introduccion-funcionamiento.md)
- [Ordenación de columnas](https://ajgallego.gitbook.io/bootstrap-4/sistema-de-rejilla/ordenacion-de-columnas.md)

## How to find the correct page

If the exact page cannot be found, you can still retrieve the information using the documentation query interface.

### Option 1 — Ask a question (recommended)

Perform an HTTP GET request on the documentation index with the `ask` parameter:

```
GET https://ajgallego.gitbook.io/bootstrap-4/introduccion.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

### Option 2 — Browse the documentation index

Full index: https://ajgallego.gitbook.io/bootstrap-4/sitemap.md

Use this to discover valid page paths or navigate the documentation structure.

### Option 3 — Retrieve the full documentation corpus

Full export: https://ajgallego.gitbook.io/bootstrap-4/llms-full.txt

Use this to access all content at once and perform your own parsing or retrieval. It will be more expensive.

## Tips for requesting documentation

Prefer `.md` URLs for structured content, append `.md` to URLs (e.g., `/bootstrap-4/introduccion.md`).

You may also use `Accept: text/markdown` header for content negotiation.