diff --git a/docs/en/Themes/Basic.md b/docs/en/Themes/Basic.md
index a0165c803a..819138de5f 100644
--- a/docs/en/Themes/Basic.md
+++ b/docs/en/Themes/Basic.md
@@ -1,3 +1,2 @@
-## Basic Theme
+This document has been moved to [here](../UI/AspNetCore/Basic-Theme.md).
 
-TODO
\ No newline at end of file
diff --git a/docs/en/UI/AspNetCore/Basic-Theme.md b/docs/en/UI/AspNetCore/Basic-Theme.md
index 3435e94a8b..5f28475f43 100644
--- a/docs/en/UI/AspNetCore/Basic-Theme.md
+++ b/docs/en/UI/AspNetCore/Basic-Theme.md
@@ -1,3 +1,90 @@
 # ASP.NET Core MVC / Razor Pages: The Basic Theme
 
-This document is in progress. See the [Theming](Theming.md) document.
\ No newline at end of file
+The Basic Theme is a theme implementation for the ASP.NET Core MVC / Razor Pages UI. It is a minimalist theme that doesn't add any styling on top of the plain [Bootstrap](https://getbootstrap.com/). You can take the Basic Theme as the **base theme** and build your own theme or styling on top of it. See the *Customization* section.
+
+The Basic Theme has RTL (Right-to-Left language) support.
+
+> If you are looking for a professional, enterprise ready theme, you can check the [Lepton Theme](https://commercial.abp.io/themes), which is a part of the [ABP Commercial](https://commercial.abp.io/).
+
+> See the [Theming document](Theming.md) to learn about themes.
+
+## Installation
+
+**This theme is already installed** when you create a new solution using the [startup templates](../../Startup-Templates/Index.md). If you need to manually install it, follow the steps below:
+
+* Install the [Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic](https://www.nuget.org/packages/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic) NuGet package to your web project.
+* Add `AbpAspNetCoreMvcUiBasicThemeModule` into the `[DependsOn(...)]` attribute for your [module class](../../Module-Development-Basics.md) in the web project.
+* Install the [@abp/aspnetcore.mvc.ui.theme.basic](https://www.npmjs.com/package/@abp/aspnetcore.mvc.ui.theme.basic) NPM package to your web project (e.g. `npm install @abp/aspnetcore.mvc.ui.theme.basic` or `yarn add @abp/aspnetcore.mvc.ui.theme.basic`).
+* Run `gulp` command in a command line terminal in the web project's folder.
+
+## Layouts
+
+The Basic Theme implements the standard layouts. All the layouts implement the following parts;
+
+* Global [Bundles](Bundling-Minification.md)
+* [Page Alerts](Page-Alerts.md)
+* [Layout Hooks](Layout-Hooks.md)
+* [Widget](Widgets.md) Resources
+
+### The Application Layout
+
+![basic-theme-application-layout](../../images/basic-theme-application-layout.png)
+
+Application Layout implements the following parts, in addition to the common parts mentioned above;
+
+* Branding
+* Main [Menu](Navigation-Menu.md)
+* Main [Toolbar](Toolbars.md) with Language Selection & User Menu
+
+### The Account Layout
+
+![basic-theme-account-layout](D:\Github\abp\docs\en\images\basic-theme-account-layout.png)
+
+Application Layout implements the following parts, in addition to the common parts mentioned above;
+
+* Branding
+* Main [Menu](Navigation-Menu.md)
+* Main [Toolbar](Toolbars.md) with Language Selection & User Menu
+* Tenant Switch Area
+
+### Empty Layout
+
+Empty layout is empty, as its name stands for. However, it implements the common parts mentioned above.
+
+## Customization
+
+You have two options two customize this theme:
+
+### Overriding Styles/Components
+
+In this approach, you continue to use the the theme as NuGet and NPM packages and customize the parts you need to. There are several ways to customize it;
+
+#### Override the Styles
+
+1. Create a CSS file in the `wwwroot` folder of your project:
+
+![example-global-styles](../../images/example-global-styles.png)
+
+2. Add the style file to the global bundle, in the `ConfigureServices` method of your [module](../../Module-Development-Basics.md):
+
+````csharp
+Configure<AbpBundlingOptions>(options =>
+{
+    options.StyleBundles.Configure(BasicThemeBundles.Styles.Global, bundle =>
+    {
+        bundle.AddFiles("/styles/global-styles.css");
+    });
+});
+````
+
+#### Override the Components
+
+See the [User Interface Customization Guide](Customization-User-Interface.md) to learn how you can replace components, customize and extend the user interface.
+
+### Copy & Customize
+
+You can download the [source code](https://github.com/abpframework/abp/tree/dev/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic) of the Basic Theme, copy the project content into your solution, re-arrange the package/module dependencies (see the Installation section above to understand how it was installed to the project) and freely customize the theme based on your application requirements.
+
+## See Also
+
+* [Theming](Theming.md)
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diff --git a/docs/en/UI/AspNetCore/Customization-User-Interface.md b/docs/en/UI/AspNetCore/Customization-User-Interface.md
index c4e196fbb9..d2a1193a53 100644
--- a/docs/en/UI/AspNetCore/Customization-User-Interface.md
+++ b/docs/en/UI/AspNetCore/Customization-User-Interface.md
@@ -132,7 +132,7 @@ The screenshot below was taken from the **basic theme** comes with the applicati
 
 ![bookstore-brand-area-highlighted](../../images/bookstore-brand-area-highlighted.png)
 
-[The basic theme](../../Themes/Basic.md) defines some view components for the layout. For example, the highlighted area with the red rectangle above is called **Brand component**. You probably want to customize this component by adding your **own application logo**. Let's see how to do it.
+[The basic theme](Basic-Theme.md) defines some view components for the layout. For example, the highlighted area with the red rectangle above is called **Brand component**. You probably want to customize this component by adding your **own application logo**. Let's see how to do it.
 
 First, create your logo and place under a folder in your web application. We used `wwwroot/logos/bookstore-logo.png` path. Then copy the Brand component's view ([from here](https://github.com/abpframework/abp/blob/dev/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Basic/Themes/Basic/Components/Brand/Default.cshtml)) from the basic theme files under the `Themes/Basic/Components/Brand` folder. The result should be similar the picture below:
 
diff --git a/docs/en/docs-nav.json b/docs/en/docs-nav.json
index 9510da38eb..c5bc0eeb3a 100644
--- a/docs/en/docs-nav.json
+++ b/docs/en/docs-nav.json
@@ -450,7 +450,13 @@
             },
             {
               "text": "Theming",
-              "path": "UI/AspNetCore/Theming.md"
+              "path": "UI/AspNetCore/Theming.md",
+              "items": [
+                {
+                  "text": "The Basic Theme",
+                  "path": "UI/AspNetCore/Basic-Theme.md"
+                }
+              ]
             },
             {
               "text": "JavaScript API",
diff --git a/docs/en/images/example-global-styles.png b/docs/en/images/example-global-styles.png
new file mode 100644
index 0000000000..04232aa62d
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