Clarify screens installation steps

Author: kacperkapusciak

src/css/custom.css

@@ -26,6 +26,8 @@
   --ifm-home-color-white: #f7f7ff;
 
   --ifm-menu-color-background-active: rgb(107, 82, 174, 0.1);
+
+  --docusaurus-highlighted-code-line-bg: #ebebeb;
 }
 
 :root[data-theme='dark'] {
@@ -42,6 +44,8 @@
   --ifm-home-color-background-secondary: #585b82;
   --ifm-home-color-highlight: #9692ff;
   --ifm-home-color-border: #f7f7ff;
+
+  --docusaurus-highlighted-code-line-bg: rgba(255, 255, 255, 0.07);
 }
 
 .menu {

versioned_docs/version-6.x/getting-started.md

@@ -68,12 +68,16 @@ npx pod-install ios
 `react-native-screens` package requires one additional configuration step to properly
 work on Android devices. Edit `MainActivity.java` file which is located in `android/app/src/main/java/<your package name>/MainActivity.java`.
 
-Add the following code to the body of `MainActivity` class:
-
-```java
-@Override
-protected void onCreate(Bundle savedInstanceState) {
-  super.onCreate(null);
+Add the highlighted code to the body of `MainActivity` class:
+
+```java {3-6}
+public class MainActivity extends ReactActivity {
+  // ...
+  @Override
+  protected void onCreate(Bundle savedInstanceState) {
+    super.onCreate(null);
+  }
+  // ...
 }
 ```
 

versioned_docs/version-7.x/getting-started.md

@@ -68,12 +68,16 @@ npx pod-install ios
 `react-native-screens` package requires one additional configuration step to properly
 work on Android devices. Edit `MainActivity.java` file which is located in `android/app/src/main/java/<your package name>/MainActivity.java`.
 
-Add the following code to the body of `MainActivity` class:
-
-```java
-@Override
-protected void onCreate(Bundle savedInstanceState) {
-  super.onCreate(null);
+Add the highlighted code to the body of `MainActivity` class:
+
+```java {3-6}
+public class MainActivity extends ReactActivity {
+  // ...
+  @Override
+  protected void onCreate(Bundle savedInstanceState) {
+    super.onCreate(null);
+  }
+  // ...
 }
 ```