Update installation.md

installation.md

@@ -12,7 +12,7 @@ Once you have installed Yggdrasil, take a look at:
 - [Public Peers](https://github.com/yggdrasil-network/public-peers) — public nodes to connect to
 - [Public Services](services.md) — services running inside the Yggdrasil Network
 
-## Linux
+### Linux
 
 Yggdrasil is well supported on Linux. There are a number of distribution packages and additional installation instructions available:
 
@@ -21,29 +21,29 @@ Yggdrasil is well supported on Linux. There are a number of distribution package
 - [Gentoo Linux](installation-linux-gentoo.md)
 - [Manual install or build from source](installation-linux-other.md)
 
-## macOS
+### macOS
 
 Yggdrasil is well supported on macOS. The preferred installation method is the `.pkg` installer:
 
 - [macOS `.pkg` installer](installation-macos-pkg.md)
 - [Manual install or build from source](installation-macos-other.md)
 
-## Windows
+### Windows
 
 Yggdrasil works on Windows and [an MSI installer is available](installation-windows.md), but the installer is supported on a best-effort basis only and is not well tested.
 
-## FreeBSD
+### FreeBSD
 
 Yggdrasil is well supported on FreeBSD and [an official `net/yggdrasil` port](https://www.freshports.org/net/yggdrasil/) is available.
 
-## Ubiquiti EdgeRouter
+### Ubiquiti EdgeRouter
 
 Yggdrasil is well supported on EdgeOS 2.x and [packages are available](installation-linux-edgeos.md).
 
-## Android
+### Android
 
 An [Yggdrasil port to Android](https://github.com/yggdrasil-network/yggdrasil-android/releases) has been contributed by the community.
 
-## iOS
+### iOS
 
 Yggdrasil is supported on iOS but no binary builds exist at this time. You will need an Apple Developer subscription, access to the Network Extensions entitlements and to [build the app from source](https://github.com/yggdrasil-network/yggdrasil-ios).