Tweak the outline headers of the Leuven theme

README.org

@@ -1142,17 +1142,47 @@ This setup prefers the ~leuven~ and ~leuven-dark~ themes from [[https://melpa.or
 very popular ~modus-operandi~ and ~modus-vivendi~ themes feel quirky: for
 instance those themes fail to display ~hl-line-mode~ with Emacs-27.2 on Darwin.
 
+[[https://emacs.stackexchange.com/questions/17431/how-do-i-change-portions-of-a-custom-theme][How to change custom theme faces]]
+
 #+attr_latex: :options bgcolor=LightGoldenrodYellow
 #+begin_src emacs-lisp
   (unless noninteractive
     ;; Try to detect `leuven-theme` from MELPA.
     (when (fboundp 'leuven-scale-font)
       (custom-set-variables
-       '(leuven-scale-org-agenda-structure nil)
-       '(leuven-scale-org-document-title nil)
-       '(leuven-scale-outline-headlines nil)
-       '(leuven-scale-volatile-highlight nil)))
-    (load-theme 'leuven 'no-confirm nil))
+       '(leuven-scale-org-agenda-structure 1.0)
+       '(leuven-scale-org-document-title 1.0)
+       '(leuven-scale-outline-headlines 1.0)
+       '(leuven-scale-volatile-highlight 1.0)))
+
+    (defun my-leuven-hook-function ()
+      (when (member 'leuven custom-enabled-themes)
+        (let ((custom-inhibit--theme-enable nil)
+              (ol1 (list :height 1.0 :weight 'bold
+                         :foreground "#3C3C3C" :background "#F0F0F0"))
+              (ol2 (list :height 1.0 :weight 'bold
+                         :foreground "#123555" :background "#E5F4FB")))
+          (custom-theme-set-faces
+           'leuven
+           `(font-latex-sectioning-2-face ((t ,ol1)))
+           `(font-latex-sectioning-3-face ((t ,ol2)))
+           `(info-title-1 ((t ,ol1)))
+           `(markdown-header-face-1 ((t ,ol1)))
+           `(markdown-header-face-2 ((t ,ol2)))
+           `(org-level-1 ((t ,ol1)))
+           `(org-level-2 ((t ,ol2)))
+           `(outline-1 ((t ,ol1)))
+           `(outline-2 ((t ,ol1)))))
+        (enable-theme 'leuven)))
+
+    (load-theme 'leuven 'no-confirm nil)
+
+    (dolist (hook '(Info-mode-hook
+                    latex-mode-hook
+                    markdown-mode-hook
+                    org-mode-hook
+                    outline-mode-hook))
+      (add-hook hook #'my-leuven-hook-function)))
 #+end_src
 
 #+attr_latex: :options bgcolor=LightGoldenrodYellow