Support margin style flag

document.go

@@ -26,21 +26,29 @@ func (e *DocumentElement) Finish(w io.Writer, node *bf.Node, tr *TermRenderer) e
 		indent = rules.Indent
 		suffix = rules.Suffix
 	}
-
+	pw := &PaddingWriter{
+		Padding: uint(tr.WordWrap + int(indent*2)),
+		PadFunc: func(wr io.Writer) {
+			renderText(w, rules, " ")
+		},
+		Forward: &AnsiWriter{
+			Forward: w,
+		},
+	}
 	iw := &IndentWriter{
 		Indent: indent,
 		Forward: &AnsiWriter{
-			Forward: w,
+			Forward: pw,
 		},
 	}
 	_, err := iw.Write(tr.document.Bytes())
 	if err != nil {
 		return err
 	}
+	renderText(iw, rules, suffix)
 
 	tr.document.Reset()
 	tr.blockStyle.Pop()
 
-	renderText(w, rules, suffix)
 	return nil
 }