Try awesome doxygen template

.github/workflows/pages.yml

@@ -160,7 +160,7 @@ jobs:
         chmod a+rwx docs_out
         docker run -v ${PWD}:/src ghcr.io/cexa-project/ddc/doxygen:${GITHUB_SHA:0:7} bash /src/run.sh
     - name: Publish site
-      if: ${{ github.event_name == 'push' && github.ref_name == 'main' && needs.id_repo.outputs.in_base_repo == 'true' }}
+      if: ${{ needs.id_repo.outputs.in_base_repo == 'true' }}
       run: |
         git fetch origin gh-pages
         git worktree add -B gh-pages public remotes/origin/gh-pages

.gitmodules

@@ -15,3 +15,6 @@
 [submodule "vendor/kokkos"]
 	path = vendor/kokkos
 	url = https://github.com/kokkos/kokkos.git
+[submodule "vendor/doxygen-awesome-css"]
+	path = vendor/doxygen-awesome-css
+	url = https://github.com/jothepro/doxygen-awesome-css.git

docs/CMakeLists.txt

@@ -12,7 +12,6 @@ if("${DOXYGEN_VERSION}" VERSION_GREATER_EQUAL 1.9.4 AND CMAKE_CXX_COMPILER_ID ST
 set(DOXYGEN_CLANG_ASSISTED_PARSING YES)
 set(DOXYGEN_CLANG_DATABASE_PATH "${CMAKE_BINARY_DIR}")
 endif()
-set(DOXYGEN_DISABLE_INDEX YES)
 set(DOXYGEN_ENUM_VALUES_PER_LINE 1)
 set(DOXYGEN_EXAMPLE_PATH "${DDC_SOURCE_DIR}/examples")
 set(DOXYGEN_EXPAND_ONLY_PREDEF YES)
@@ -21,18 +20,16 @@ set(DOXYGEN_EXCLUDE_SYMBOLS "detail")
 set(DOXYGEN_EXCLUDE_PATTERNS "*/experimental/*;*/detail/*")
 set(DOXYGEN_EXTRACT_LOCAL_CLASSES YES)
 set(DOXYGEN_FULL_PATH_NAMES NO)
-set(DOXYGEN_GENERATE_TREEVIEW YES)
-set(DOXYGEN_HTML_FOOTER "${CMAKE_CURRENT_SOURCE_DIR}/_template/footer.html")
-set(DOXYGEN_HTML_HEADER "${CMAKE_CURRENT_SOURCE_DIR}/_template/header.html")
-set(DOXYGEN_HTML_STYLESHEET "${CMAKE_CURRENT_SOURCE_DIR}/_template/style.css")
+set(DOXYGEN_HTML_HEADER "${PROJECT_SOURCE_DIR}/vendor/doxygen-awesome-css/doxygen-custom/header.html")
+set(DOXYGEN_HTML_STYLESHEET "${PROJECT_SOURCE_DIR}/vendor/doxygen-awesome-css/doxygen-custom/custom.css")
 set(DOXYGEN_HTML_OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/html")
 set(DOXYGEN_HTML_TIMESTAMP NO)
 set(DOXYGEN_INCLUDE_GRAPH NO)
 set(DOXYGEN_INCLUDE_PATH "${DDC_SOURCE_DIR}/include/")
 set(DOXYGEN_INCLUDED_BY_GRAPH NO)
 set(DOXYGEN_INLINE_SIMPLE_STRUCTS YES)
 set(DOXYGEN_JAVADOC_AUTOBRIEF YES)
-set(DOXYGEN_LAYOUT_FILE "${CMAKE_CURRENT_SOURCE_DIR}/_template/layout.xml")
+# set(DOXYGEN_LAYOUT_FILE "${CMAKE_CURRENT_SOURCE_DIR}/_template/layout.xml")
 set(DOXYGEN_MACRO_EXPANSION YES)
 set(DOXYGEN_PREDEFINED "DOXYGEN_IGNORE")
 set(DOXYGEN_PROJECT_LOGO "${CMAKE_CURRENT_SOURCE_DIR}/_template/logo.png")
@@ -48,14 +45,21 @@ set(DOXYGEN_TOC_INCLUDE_HEADINGS 4)
 set(DOXYGEN_TYPEDEF_HIDES_STRUCT YES)
 set(DOXYGEN_UML_LIMIT_NUM_FIELDS 20)
 set(DOXYGEN_UML_LOOK YES)
-set(DOXYGEN_WARN_IF_UNDOCUMENTED NO CACHE STRING "")
+set(DOXYGEN_WARN_IF_UNDOCUMENTED YES CACHE STRING "")
 set(DOXYGEN_WARN_IF_DOC_ERROR YES CACHE STRING "")
 set(DOXYGEN_WARN_IF_INCOMPLETE_DOC YES CACHE STRING "")
 set(DOXYGEN_WARN_NO_PARAMDOC YES CACHE STRING "")
 set(DOXYGEN_WARN_IF_UNDOC_ENUM_VAL YES CACHE STRING "")
-set(DOXYGEN_WARN_AS_ERROR YES CACHE STRING "")
+set(DOXYGEN_WARN_AS_ERROR NO CACHE STRING "")
 set(DOXYGEN_WARN_LOGFILE "doxygen.log")
 set(DOXYGEN_IMAGE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/images")
+
+set(DOXYGEN_GENERATE_TREEVIEW YES) # optional. Also works without treeview
+set(DOXYGEN_DISABLE_INDEX NO)
+set(DOXYGEN_FULL_SIDEBAR NO)
+set(DOXYGEN_HTML_EXTRA_STYLESHEET ${CMAKE_CURRENT_SOURCE_DIR}/_template/doxygen-awesome-css/doxygen-awesome.css)
+set(DOXYGEN_HTML_COLORSTYLE LIGHT) # required with Doxygen >= 1.9.5
+
 doxygen_add_docs(doc
         "${CMAKE_CURRENT_SOURCE_DIR}/About.md"
         "${CMAKE_CURRENT_SOURCE_DIR}/first_steps.md"