diff --git a/README.md b/README.md
index ee8e78c..d201623 100644
--- a/README.md
+++ b/README.md
@@ -1,12 +1,19 @@
 # bootstrap-auto-dark-mode
 
-Include this script to set the bootstrap >= 5.3 dark-mode automatically based on system settings.
+This script adds the missing auto-dark mode to the new theme feature of Bootstrap 5.3.
 
-The mode will switch automatically, also when the user changes the system settings while the page is shown.
+It switches the Bootstrap theme automatically between light and dark mode, depending on the system settings, if you set the `data-bs-theme` attribute of your &lt;html> to `auto`.
 
 ## Usage
 
-```html
-<script src="./src/bootstrap-auto-dark-mode.js"></script>
-```
+Use it by just including `bootstrap-auto-dark-mode.js` in your header and setting `data-bs-theme` to `auto`.
 
+```html
+    <html data-bs-theme="auto">
+        <head>
+            <!-- you code -->
+            <script src="./src/bootstrap-auto-dark-mode.js"></script>
+        </head>
+        <!-- your code -->
+        …
+```
diff --git a/index.html b/index.html
index 18c9f2e..3fcf44d 100644
--- a/index.html
+++ b/index.html
@@ -1,5 +1,5 @@
 <!doctype html>
-<html lang="en">
+<html lang="en" data-bs-theme="auto">
 <head>
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
@@ -12,14 +12,33 @@
 
 <h1>bootstrap-auto-dark-mode</h1>
 
-<p>This script automatically switches the Bootstrap theme between light and dark mode, depending on the system settings.</p>
+<p>This script adds an auto-dark mode to the new theme feature of Bootstrap 5.3.</p>
 
-<p>Use it by just including <code>bootstrap-auto-dark-mode.js</code> in your header.</p>
+<p>It switches the Bootstrap theme automatically between light and dark mode, depending on the system settings, if
+    you set the <code>data-bs-theme</code> attribute of your <code>&lt;html></code> to <code>auto</code>.</p>
+
+<p>Use it by just including <code>bootstrap-auto-dark-mode.js</code> in your header and setting <code>data-bs-theme</code> to <code></code>auto</code>.</p>
 
 <code>
-    &lt;script src="./src/bootstrap-auto-dark-mode.js">&lt;/script>
+    <pre>
+    &lt;html data-bs-theme="<b class="text-success">auto</b>">
+        &lt;head>
+            […]
+            <b class="text-success">&lt;script src="./src/bootstrap-auto-dark-mode.js">&lt;/script></b>
+        &lt;/head>
+        […]
+    </pre>
 </code>
 
+<h2>Switch manually</h2>
+
+<button class="btn btn-primary" onclick="document.documentElement.setAttribute('data-bs-theme', 'light')">Light
+    mode
+</button>
+<button class="btn btn-primary" onclick="document.documentElement.setAttribute('data-bs-theme', 'dark')">Dark
+    mode
+</button>
+
 <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/js/bootstrap.bundle.min.js"
         integrity="sha384-geWF76RCwLtnZ8qwWowPQNguL3RmwHVBC9FhGdlKrxdiJJigb/j/68SIy3Te4Bkz"
         crossorigin="anonymous"></script>
diff --git a/package.json b/package.json
index b07993f..9a751fa 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "bootstrap-auto-dark-mode",
   "version": "1.0.1",
-  "description": "Switches the bootstrap >= 5.3 dark-mode automatically based on system settings.",
+  "description": "Adds the missing auto dark mode to Bootstrap >= 5.3, which switches automatically, based on system settings.",
   "main": "index.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"
