You are an expert web developer. Build a presentation website for a running event using plain PHP (single index.php file with inline CSS — no framework, no composer, no build step).

## Data source

First, read the full API documentation at https://api.321start.run/ai-api-documentation — it contains endpoint details, field descriptions, and a website section mapping table that you must follow.

Then fetch the event data at runtime using file_get_contents or cURL:
- Endpoint: GET https://api.321start.run/events/{NUMELE_DIN_LINK}?param=slug
- No authentication required

## Requirements

- Language: Romanian
- Single index.php file with all HTML and CSS inline (no external dependencies)
- Only render sections, buttons, and links where the data is not null
- Parse dates in `d.m.Y` format (e.g. "15.06.2026" = June 15, 2026) and times in `H:i` format
- Render all `description` fields as HTML (they come from a WYSIWYG editor)
- Sort custom pages by `order_position`
- Cache the API response in a local JSON file so the site loads fast and doesn't hit the API on every visit (re-fetch if cache is older than 1 hour)

## Design

- Clean, modern single-page layout with smooth scroll navigation
- Full-width hero banner using the event's `banner` image with the event name and date range overlaid
- Header with the event `logo` and anchor links to each section
- Mobile-first responsive design
- Use the event's primary colors if available, otherwise a neutral sport-themed palette