Attributes#

An attribute block is a list of items in braces:

{#install .wide width=320 title="Getting started" open}

Items are separated by spaces or commas: {type=bar, title=Sales} is valid. Unquoted values cannot contain whitespace, quotes, =, `, {, } or ,.

Where attributes are allowed#

Directives, after the name or label:

:::note[Heads up]{#release-note collapsible}
Collapsible callouts render as a `details` element.
:::

Headings, at the end of the line:

### Configuration file {#config}

Images, directly after the closing parenthesis:

![Logo](logo.png){width=120 .round}

Code blocks, after the language:

```sh {title="Terminal"}
markup check docs
```

markup check docs

For headings and images, braces are only read as attributes when the first item is #id, .class or key=value, so # Using {braces} keeps its text.

Values and validation#

Attribute values are text. Each component declares a type for every attribute, and values are converted before rendering: value=72 becomes the number 72, open or open=true the boolean true. The declared attributes of every built-in component are in Components.

Problems are reported with the position of the item:

#id and .class are accepted by every component.