mention config.card in templates in README

README.md

@@ -276,7 +276,7 @@ Touchpads can have a separate icon and label for the center and each direction.
 
 Almost all fields support nunjucks templating. Nunjucks is a templating engine for JavaScript, which is heavily based on the jinja2 templating engine for Python which Home Assistant uses. While the syntax of nunjucks and jinja2 is almost identical, you may find the [nunjucks documentation](https://mozilla.github.io/nunjucks/templating.html) useful. Most extensions supported by Home Assistant templates are supported by this templating system, but not all and the syntax may vary. Please see the [ha-nunjucks](https://github.com/Nerwyn/ha-nunjucks) repository for a list of available extensions. If you want additional extensions to be added or have templating questions or bugs, please make an issue or discussion on that repository, not this one.
 
-You can include the current value of a remote element and it's units by using the variables `value` and `unit` in a label template. You can also include `hold_secs` in a template if performing a momentary end action. Each remote element can also reference it's configuration using `config` within templates. `config.entity` and `config.attribute` will return the remote element's entity ID and attribute with their templates rendered (if they have them), and other templated config fields can be rendered within templates by wrapping them in the function `render` within a template.
+You can include the current value of a remote element and it's units by using the variables `value` and `unit` in a label template. You can also include `hold_secs` in a template if performing a momentary end action. Each remote element can also reference it's configuration using `config` within templates. `config.entity` and `config.attribute` will return the remote element's entity ID and attribute with their templates rendered (if they have them), and other templated config fields can be rendered within templates by wrapping them in the function `render` within a template. You can access the entire card config in a template via `config.card`, and global values such as remote ID within that like `config.card.remote_id`. Note that default values for some fields are not actually in the config and will not appear in templates, and you have to default to them using "or", like `config.card.platform or 'Android TV'`.
 
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