Videos
To embed a video, add URL inside a fenced code block with the video identifier.
```video
https://www.youtube.com/watch?v=RcnksOUugcA
```
The default player aspect ratio is 4:3. You can set ratio by ratio=16:9, and set max width with 640px by max-width=640. Alignment can also be set to left, center or right:
```video ratio=16:9 max-width=640 align=center
https://www.youtube.com/watch?v=RcnksOUugcA
```