diff --git a/build.sh b/build.sh
index 58267c1..fa42c3d 100755
--- a/build.sh
+++ b/build.sh
@@ -1,4 +1,5 @@
 #!/bin/bash
 set -e  # exit when any command fails
 asciidoctor livro.adoc -o index.html
+sed -i -e 's/<img/& loading="lazy" /g' index.html # add lazy loading to images
 open index.html
diff --git a/livro.adoc b/livro.adoc
index 1c4c379..8c1d1ef 100644
--- a/livro.adoc
+++ b/livro.adoc
@@ -7,7 +7,6 @@ include::atributos-pt_BR.adoc[]
 :xrefstyle: short
 :sectnums:
 :sectlinks:
-:data-uri:
 :toc:
 :toclevels: 2
 :!chapter-signifier:
@@ -159,4 +158,4 @@ include::capitulos/cap21.adoc[]
 
 == 🚧 Descritores de atributos
 
-== 🚧 Metaprogramação com classes
\ No newline at end of file
+== 🚧 Metaprogramação com classes