diff --git a/Makefile b/Makefile
index 8b9b9a5..b76aec2 100644
--- a/Makefile
+++ b/Makefile
@@ -28,11 +28,11 @@ pdf: $(BUILD)/pdf/$(BOOKNAME).pdf
 
 $(BUILD)/epub/$(BOOKNAME).epub: $(TITLE) $(CHAPTERS) $(METADATA_YAML)
 	mkdir -p $(BUILD)/epub
-	pandoc -s $(TOC) --chapters --number-offset=0 -S --epub-metadata=$(METADATA_XML) --epub-cover-image=$(COVER_IMAGE) -o $@ $^
+	pandoc -s $(TOC) --top-level-division --number-offset=0 -S --epub-metadata=$(METADATA_XML) --epub-cover-image=$(COVER_IMAGE) -o $@ $^
 
 $(BUILD)/html/$(BOOKNAME).html: $(CHAPTERS) $(METADATA_YAML)
 	mkdir -p $(BUILD)/html
-	pandoc -s $(TOC) --chapters --number-offset=0 --standalone --to=html5 --css=css/$(BOOKNAME).css -o $@ $^
+	pandoc -s $(TOC) --top-level-division --number-offset=0 --standalone --to=html5 --css=css/$(BOOKNAME).css -o $@ $^
 
 $(BUILD)/html/fonts/%: fonts/%
 	mkdir -p $(BUILD)/html/fonts