feat: add new documentation pages

docs/src/content/docs/reference/errors.mdx

@@ -1,3 +1,92 @@
 ---
 title: Errors
 ---
+
+import Seo from '../../../components/Seo.astro'
+
+<Seo
+    seo={{
+        title: 'Errors',
+        description: 'Errors Unistyles will throw',
+    }}
+>
+
+Unistyles will only throw errors when it is used incorrectly.
+
+### RuntimeUnavailable
+
+*"Unistyles runtime is not available. Make sure you followed the installation instructions"*
+
+This error will be thrown if you try to use Unistyles before it was initialized. 
+Make sure you followed the installation [setup](/start/setup/).
+
+Still getting this error? Check [FAQ](/reference/faq/).
+
+### ThemeNotFound / ThemeNotRegistered
+
+*"You are trying to get a theme that is not registered with UnistylesRegistry"*
+
+and
+
+*"You are trying to set a theme that was not registered with UnistylesRegistry"*
+
+These errors occur when you call `UnistylesRuntime.setTheme` with a theme that has not been registered with `UnistylesRegistry`.
+This situation can arise if you don't use TypeScript. Confirm that all your themes are registered with `UnistylesRegistry.addThemes` before using them.
+
+### ThemeNotSelected
+
+*"Your themes are registered, but you didn't select the initial theme"*
+
+This error is thrown if you have registered multiple themes but failed to select an initial one.
+
+Follow theming [guide](/reference/theming/) to learn how to select the initial theme.
+
+### ThemesCannotBeEmpty
+
+*"You are trying to register empty themes object"*
+
+This error occurs if you attempt to register an empty themes object with  `UnistylesRegistry.addThemes`.
+
+The `addThemes` method expects a key-value pair with at least one theme.
+
+Follow theming [guide](/reference/theming/) to learn how to register your themes.
+
+If you don't want to use themes, simply don't register them.
+
+### BreakpointsCannotBeEmpty
+
+*"You are trying to register empty breakpoints object"*
+
+This error will be thrown if you try to register empty breakpoints object with `UnistylesRegistry.addBreakpoints`.
+
+Breakpoints are optional, if you don't want to use them, simply don't register them.
+
+### BreakpointsMustStartFromZero
+
+*"You are trying to register breakpoints that don't start from 0"*
+
+This error occurs when you attempt to register breakpoints that do not start from 0.
+Begin your first breakpoint with a value of 0 to mimic CSS cascade.
+
+### InvalidPluginName
+
+*"Plugin name can't start from reserved prefix __unistyles"*
+
+This error is thrown if you attempt to register a plugin with a name that begins with the `__unistyles` prefix.
+This prefix is reserved for Unistyles' internal plugins.
+
+### DuplicatePluginName
+
+*"You are trying to register a plugin with a name that is already registered"*
+
+This error occurs when you attempt to register a plugin with a name that has already been registered.
+Review your list of plugins. Perhaps you included the same plugin twice? Or, maybe a plugin with the same name has already been created by someone from the community?
+
+### CantRemoveInternalPlugin
+
+*"You are trying to remove an internal unistyles plugin"*
+
+This error is thrown if you attempt to remove an internal Unistyles plugin.
+Currently, it's not possible to remove internal plugins as they are essential for Unistyles to function properly.
+
+</Seo>

docs/src/content/docs/reference/faq.mdx

@@ -1,3 +1,62 @@
 ---
 title: FAQ
 ---
+
+import { Card, CardGrid } from '@astrojs/starlight/components'
+import Seo from '../../../components/Seo.astro'
+
+<Seo
+    seo={{
+        title: 'FAQ',
+        description: 'Frequently asked questions about the Unistyles'
+    }}
+>
+
+Here, you can find answers to the most frequently asked questions about Unistyles.
+
+### Why Unistyles runtime is not available?
+
+This error occurs when you try to use a Unistyles feature without proper installation.
+
+Possible causes include:
+- Running the app in Expo Go, which is not supported.
+- Running your Expo project without rebuilding it using the `expo prebuild` command
+- Forgetting to execute `pod install` in your bare React Native project
+- Omitting the import of the file where you set up your UnistylesRegistry eg. in your `App.tsx` file
+
+### I'm trying to override library types, but I'm receiving error that react-native-unistyles is not found?
+
+To override types, you must import something from `react-native-unistyles`, such as `UnistylesRegistry`.
+
+### Adaptive mode doesn't work for me
+
+To enable adaptive mode, you need to register two themes named `light` and `dark` and set the `adaptiveThemes` flag to true within `UnistylesRegistry`.
+
+If your app still doesn't automatically switch themes, ensure that:
+- For Expo your `app.json` contains a `userInterfaceStyle` key with the value `automatic`
+- For bare React Native, your `Info.plist` does not have the `UIUserInterfaceStyle` key set to a hardcoded value
+- `Appearance` from `react-native` is set to `null`
+- You have phone with iOS 13+ or Android 10+
+- Your device supports dark mode
+
+### I'm getting some TypeScript error for my stylesheet
+
+This should not occur, but if it does, please create a new issue in the GitHub repository.
+
+Unistyles is built with first-class support for TypeScript, inferring all the types for you. 
+There should be no need for extra steps. Please include your stylesheet and the error you're encountering in the issue.
+
+### Does Unistyles support PlatformColor?
+
+Yes, it does! You can even use PlatformColor in your themes!
+
+### Are class components supported?
+
+No, the library only supports functional components. 
+If you need support for class components, you would need to create a wrapper component.
+
+### How to use Unistyles with Expo?
+
+Unistyles supports Expo. However, it can't be used with Expo Go.
+
+</Seo>

docs/src/content/docs/reference/for-library-authors.mdx

@@ -1,3 +1,118 @@
 ---
 title: For library authors
 ---
+
+import Seo from '../../../components/Seo.astro'
+
+<Seo
+    seo={{
+        title: 'For library authors',
+        description: 'A guide for library authors on how to use Unistyles in their projects.'
+    }}
+>
+
+Unistyles is highly extensible and can be utilized to build UI Kits and other kinds of projects.
+
+## Using Unistyles in your library
+
+`UnistylesRegistry` can be invoked lazily after resolving user-required configurations, such as themes and plugins.
+
+You can call `UnistylesRegistry` multiple times to override configurations. 
+However, keep in mind that `UnistylesRegistry` makes a roundtrip to C++, which can add up to **1ms** of additional setup time for Unistyles.
+
+To manipulate your config without replacing it, you should use [UnistylesRuntime](/reference/unistyles-runtime/).
+
+## Timing
+
+Unistyles core does not have an asynchronous API. 
+This means you can invoke `UnistylesRegistry` right before the first `useStyle` call:
+
+```tsx
+import { UnistylesRegistry, useInitialTheme, useStyles } from 'react-native-unistyles'
+
+export const App: React.FunctionComponent = () => {
+    UnistylesRegistry
+        .addConfig(...)
+        .addBreakpoints(...)
+
+    useInitialTheme('dark')
+
+    const { styles } = useStyles(stylesheet)
+
+    return (
+        // your app
+    )
+}
+
+// stylesheet
+```
+
+:::tip
+Registering themes at runtime is also possible, although it is not yet implemented in the core. 
+If you need this feature, please open a discussion.
+:::
+
+## Plugins
+
+You can extend Unistyles with your plugins that may transform the output to the desired style.
+Currently, Unistyles supports one lifecycle hook: [onParsedStyle](/reference/plugins/).
+
+## When does Unistyles re-render?
+
+Unistyles only re-renders when it receives an event from C++. This means `useStyles` supports component memoization.
+
+You should expect re-renders only when:
+- The theme changes.
+- The device orientation changes.
+- The screen size changes (web only).
+- A plugin is registered or unregistered.
+
+:::tip
+Storing library config in `UnistylesRuntime` is also a possibility. 
+If you need this feature, please open a discussion.
+:::
+
+## No React Context
+
+Unistyles does not use the React Context API. This means that users do not need to wrap their app with a `Provider`, 
+reducing boilerplate and making your library more user-friendly.
+
+## New architecture ready
+
+Unistyles handles all native configurations and supports new architecture, 
+ensuring you don't need to worry about Fabric or other low-level concepts.
+
+Your UI Kit can support all React Native apps out of the box.
+
+## Minimum requirements
+
+Unistyles is compatible with:
+- React Native version >=0.66
+- TypeScript >4.0
+- iOS 13+
+- Android 5+
+
+## CSS styles
+
+There is ongoing work on custom CSS compiler that could
+entirely replace the React Native Web StyleSheet API,
+offering better Developer Experience (DX) and more predictable re-renders, e.g. with media queries.
+
+Unistyles 2.0 was developed with this feature in mind. 
+If you are interested, please open a discussion and share your use case.
+
+## Why choose Unistyles?
+
+Unistyles offers a unique architecture not available in any other library. Built on top of the React Native StyleSheet API, it is fully compatible with it.
+
+Without component abstraction, you have the freedom to build one. Unistyles supports various platforms and is easily extendable, particularly with plugins and variants.
+
+With its smart architecture, you can maintain the same rendering time as the [core](/start/benchmarks/).
+
+:::tip
+If you need any cool feature to support your UI Kit, please open a discussion.
+
+I'm happy to help you with your use case!
+:::
+
+</Seo>