diff --git a/README.md b/README.md
index 09c9b2b..8c60faa 100644
--- a/README.md
+++ b/README.md
@@ -3,11 +3,11 @@
 Format and reformat ascii proof trees like this one:
 
 ```text
-§                                                  *
-§                                    ----------------------------- [;] compose
-§                                    [a;b;]p(||) <-> [a;][b;]p(||)
-§                              ----------------------------------------- US
-§ [x:=*;][?x>0;][x:=x+1;]x>1   [?x>0;x:=x+1;]x>1 <-> [?x>0;][x:=x+1;]x>1
-§ ---------------------------------------------------------------------- RewriteAt
-§                        [x:=*;][?x>0;x:=x+1;]x>1
+§                                                   *
+§                                     ----------------------------- [;] compose
+§                                     [a;b;]p(||) <-> [a;][b;]p(||)
+§                               ----------------------------------------- US
+§  [x:=*;][?x>0;][x:=x+1;]x>1   [?x>0;x:=x+1;]x>1 <-> [?x>0;][x:=x+1;]x>1
+§  ---------------------------------------------------------------------- RewriteAt
+§                         [x:=*;][?x>0;x:=x+1;]x>1
 ```
diff --git a/src/main/scala/de/plugh/asciiprooftree/file/Block.scala b/src/main/scala/de/plugh/asciiprooftree/file/Block.scala
index 7b39ed1..82d01a7 100644
--- a/src/main/scala/de/plugh/asciiprooftree/file/Block.scala
+++ b/src/main/scala/de/plugh/asciiprooftree/file/Block.scala
@@ -5,7 +5,7 @@ case class Block(lines: Seq[(String, String)]):
 
   def last: (String, String) = lines.last
   def content: Seq[String] = lines.map((_, content) => content)
-  def toLines: Seq[String] = lines.map((prefix, content) => s"$prefix $content")
+  def toLines: Seq[String] = lines.map((prefix, content) => s"$prefix  $content")
 
   def extend(prefix: String, content: String): Block = Block(lines :+ (prefix, content))