diff --git a/spec/src/main/asciidoc/cdi-spec.asciidoc b/spec/src/main/asciidoc/cdi-spec.asciidoc
index 76724bc3..aaecdf30 100644
--- a/spec/src/main/asciidoc/cdi-spec.asciidoc
+++ b/spec/src/main/asciidoc/cdi-spec.asciidoc
@@ -33,9 +33,10 @@ include::architecture.asciidoc[]
 [[part_1]]
 = Part I - Core CDI
 
-== {cdi_lite}
+include::core/core_structure.adoc[]
 
-:leveloffset: +1
+[[part_1a]]
+= Part I.A - {cdi_lite}
 
 include::core/definition.asciidoc[]
 
@@ -59,11 +60,8 @@ include::core/spi_lite.asciidoc[]
 
 include::core/packagingdeployment.asciidoc[]
 
-:leveloffset: -1
-
-== {cdi_full}
-
-:leveloffset: +1
+[[part_1b]]
+= Part I.B - {cdi_full}
 
 include::core/definition_full.asciidoc[]
 
@@ -85,8 +83,6 @@ include::core/spi_full.asciidoc[]
 
 include::core/packagingdeployment_full.asciidoc[]
 
-:leveloffset: -1
-
 [[part_2]]
 = Part II - CDI in Java SE
 
diff --git a/spec/src/main/asciidoc/core/core_structure.adoc b/spec/src/main/asciidoc/core/core_structure.adoc
new file mode 100644
index 00000000..a6381b12
--- /dev/null
+++ b/spec/src/main/asciidoc/core/core_structure.adoc
@@ -0,0 +1,10 @@
+:numbered!:
+
+== Structure
+
+The Core CDI specification has two subparts:
+
+* {cdi_lite} specification which contains a subset of CDI features and which can be implemented in more restricted environments; this is part of the Jakarta EE Core Profile;
+* {cdi_full} specification that builds on top of Lite and adds all advanced CDI features; this is the classic CDI platform that is part of the Jakarta EE Web Profile and Jakarta EE Platform.
+
+:numbered:
diff --git a/spec/src/main/asciidoc/core/definition_full.asciidoc b/spec/src/main/asciidoc/core/definition_full.asciidoc
index 486e6610..98dcb010 100644
--- a/spec/src/main/asciidoc/core/definition_full.asciidoc
+++ b/spec/src/main/asciidoc/core/definition_full.asciidoc
@@ -1,7 +1,8 @@
-[[concepts_full]]
-
+[partintro]
+--
 {cdi_full} contains all the functionality defined in {cdi_lite} and adds some additional features such as specialization, decorators, session scope or conversation scope.
 Some of these concepts were briefly mentioned in the previous {cdi_lite} chapter and this section of specification defines them in depth.
+--
 
 [[scopes_full]]
 
diff --git a/spec/src/main/asciidoc/preface.asciidoc b/spec/src/main/asciidoc/preface.asciidoc
index eeee2f9a..d14a4b77 100644
--- a/spec/src/main/asciidoc/preface.asciidoc
+++ b/spec/src/main/asciidoc/preface.asciidoc
@@ -15,9 +15,9 @@ include::license-{license}.asciidoc[]
 This document is organized in 4 parts:
 
 * An introduction (this part), which is not part of the specification but introduces CDI concepts and gives examples.
-* Core CDI specification: <<part_1>>. This part has two sections:
-** {cdi_lite} specification which contains a subset of CDI features and which can be implemented in more restricted environments;
-** {cdi_full} specification that builds on top of Lite and adds all advanced CDI features; this is the standard Jakarta EE CDI platform.
+* Core CDI specification: <<part_1>>. This part has two subparts:
+** {cdi_lite} specification: <<part_1a>>;
+** {cdi_full} specification: <<part_1b>>.
 * Specific CDI features for Java SE: <<part_2>>.
 * Specific CDI features for Jakarta EE: <<part_3>>.