fix(articles): find .md by slug scan + lighter editor theme

Two fixes:
- _find_article_md() scans _ARTICLES_DIR for files whose frontmatter
  slug matches, so padel-halle-bauen-de.md is found for slug
  'padel-halle-bauen'. The previous exact-name lookup missed any file
  where the filename ≠ slug (e.g. {slug}-{lang}.md naming convention).
- Editor pane: replace dark navy background with warm off-white (#FEFDFB)
  and dark text so it reads like a document, not a code editor.

web/src/padelnomics/admin/routes.py

@@ -2203,6 +2203,27 @@ _ARTICLES_DIR = Path(__file__).parent.parent.parent.parent.parent / "data" / "co
 _FRONTMATTER_RE = re.compile(r"^---\s*\n(.*?)\n---\s*\n", re.DOTALL)
 
 
+def _find_article_md(slug: str) -> Path | None:
+    """Return the Path of the .md file whose frontmatter slug matches, or None.
+
+    Tries the exact name first ({slug}.md), then scans _ARTICLES_DIR for any
+    file whose YAML frontmatter contains 'slug: <slug>'. This handles the
+    common pattern where files are named {slug}-{lang}.md but the frontmatter
+    slug omits the language suffix.
+    """
+    if not _ARTICLES_DIR.is_dir():
+        return None
+    exact = _ARTICLES_DIR / f"{slug}.md"
+    if exact.exists():
+        return exact
+    for path in _ARTICLES_DIR.glob("*.md"):
+        raw = path.read_text(encoding="utf-8")
+        m = _FRONTMATTER_RE.match(raw)
+        if m and f"slug: {slug}" in m.group(1):
+            return path
+    return None
+
+
 async def _sync_static_articles() -> None:
     """Upsert static .md articles from data/content/articles/ into the DB.
 
@@ -2626,11 +2647,12 @@ async def article_edit(article_id: int):
 
     # Load markdown source if available (manual or generated)
     from ..content.routes import BUILD_DIR as CONTENT_BUILD_DIR
-    md_path = _ARTICLES_DIR / f"{article['slug']}.md"
-    if not md_path.exists():
+    md_path = _find_article_md(article["slug"])
+    if md_path is None:
         lang = article["language"] or "en"
-        md_path = CONTENT_BUILD_DIR / lang / "md" / f"{article['slug']}.md"
-    raw = md_path.read_text() if md_path.exists() else ""
+        fallback = CONTENT_BUILD_DIR / lang / "md" / f"{article['slug']}.md"
+        md_path = fallback if fallback.exists() else None
+    raw = md_path.read_text() if md_path else ""
     # Strip YAML frontmatter so only the prose body appears in the editor
     m = _FRONTMATTER_RE.match(raw)
     body = raw[m.end():].lstrip("\n") if m else raw

web/src/padelnomics/admin/templates/admin/article_form.html

@@ -156,8 +156,8 @@
     align-items: center;
     justify-content: space-between;
     padding: 0.375rem 0.875rem;
-    background: #1E293B;
-    border-bottom: 1px solid #0F172A;
+    background: #F8FAFC;
+    border-bottom: 1px solid #E2E8F0;
     flex-shrink: 0;
   }
   .ae-pane--preview .ae-pane__header {
@@ -171,13 +171,11 @@
     letter-spacing: 0.09em;
     color: #94A3B8;
   }
-  .ae-pane--editor .ae-pane__label { color: #475569; }
   .ae-pane__hint {
     font-size: 0.625rem;
     font-family: var(--font-mono);
-    color: #475569;
+    color: #94A3B8;
   }
-  .ae-pane--preview .ae-pane__hint { color: #94A3B8; }
 
   /* The markdown textarea */
   .ae-editor {
@@ -185,16 +183,16 @@
     resize: none;
     border: none;
     outline: none;
-    padding: 1.125rem 1.25rem;
+    padding: 1.5rem 2rem;
     font-family: var(--font-mono);
-    font-size: 0.8125rem;
-    line-height: 1.75;
-    background: #0F172A;
-    color: #CBD5E1;
-    caret-color: #3B82F6;
+    font-size: 0.875rem;
+    line-height: 1.8;
+    background: #FEFDFB;
+    color: #1E293B;
+    caret-color: #1D4ED8;
     tab-size: 2;
   }
-  .ae-editor::placeholder { color: #334155; }
+  .ae-editor::placeholder { color: #CBD5E1; }
   .ae-editor:focus { outline: none; }
 
   /* Preview pane */
@@ -283,9 +281,15 @@
     color: #94A3B8;
     font-family: var(--font-mono);
     opacity: 0;
-    transition: opacity 0.15s;
+    transition: opacity 0.2s;
   }
   .ae-loading.htmx-request { opacity: 1; }
+
+  /* Responsive: stack on narrow screens */
+  @media (max-width: 900px) {
+    .ae-split { grid-template-columns: 1fr; }
+    .ae-pane--preview { display: none; }
+  }
 </style>
 {% endblock %}