diff --git a/Makefile b/Makefile
index b7e332a..ac8d78f 100644
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@
 help:
 	@echo "Please use \`make <target>' where <target> is one of"
 	@echo "  pdf        to make standalone PDF files"
-	
+
 clean:
 	rm -rf $(BUILDDIR)/*
 
@@ -14,4 +14,4 @@ html:
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."
 
 pdf:
-	asciidoctor-pdf -a pdf-themesdir=resources/themes -a pdf-theme=gwift-theme source/main.adoc -t -r asciidoctor-diagram
+	asciidoctor-pdf -a pdf-themesdir=resources/themes -a pdf-theme=book.yml source/main.adoc -t
diff --git a/resources/themes/basic-theme.yml b/resources/themes/book.yml
similarity index 83%
rename from resources/themes/basic-theme.yml
rename to resources/themes/book.yml
index 7c737fd..d35a223 100644
--- a/resources/themes/basic-theme.yml
+++ b/resources/themes/book.yml
@@ -11,4 +11,7 @@ admonition:
     caution:
       name: fa-fire
       stroke_color: ff0000
-      size: 24
\ No newline at end of file
+      size: 24
+image:
+  caption:
+    align: inherit
\ No newline at end of file