fonts: add --font-body/--font-display vars, use them everywhere

TODO.md

@@ -3,12 +3,10 @@
 ## Completed
 
 - [x] Apply correct fonts site-wide
-  - Registered `Combined` (@font-face, replaces old `police1`) and all 4 weights of `BBBDMSans` in `common.css`
-  - `body` now uses `BBBDMSans` as base font
-  - Header brand logo keeps `Combined`
-  - `tfe.css`: `.tfe-title` and `.tfe-author` use `Combined`
-  - `apropos.css`: prose body → `BBBDMSans`; h1/h2/h3, `.apropos-section-title`, `.apropos-licences h2` → `Combined`
-  - Code blocks keep `Courier New` monospace
+  - Registered `Combined` and all 4 weights of `BBBDMSans` via `@font-face` in `common.css`
+  - Added `--font-body` and `--font-display` CSS variables in `variables.css`
+  - All font usages across `common.css`, `tfe.css`, `apropos.css` use `var(--font-body)` / `var(--font-display)`
+  - Code blocks keep `Courier New` monospace (intentional)
 
 - [x] Répertoire: rename search.php → repertoire.php, 6-column layout (AP + Orientations split, Finalité du Master added), HTMX server-side intersection filter, faded entries disabled, URL-shareable state
 - [x] Match Accueil.png mockup