Categorized tags in info panel with color coding

- Artist (gold), Character (green), Copyright (purple), Species
  (red), General, Meta/Lore (gray)
- Danbooru and e621 provide categories from API
- Gelbooru/Moebooru fall back to flat tag list

booru_viewer/core/api/base.py

@@ -25,6 +25,7 @@ class Post:
     source: str | None
     width: int = 0
     height: int = 0
+    tag_categories: dict[str, list[str]] = field(default_factory=dict)
 
     @property
     def tag_list(self) -> list[str]:

booru_viewer/core/api/danbooru.py

@@ -51,6 +51,7 @@ class DanbooruClient(BooruClient):
                     source=item.get("source"),
                     width=item.get("image_width", 0),
                     height=item.get("image_height", 0),
+                    tag_categories=self._extract_tag_categories(item),
                 )
             )
         return posts
@@ -105,3 +106,19 @@ class DanbooruClient(BooruClient):
             if key in item and item[key]:
                 parts.append(item[key])
         return " ".join(parts) if parts else ""
+
+    @staticmethod
+    def _extract_tag_categories(item: dict) -> dict[str, list[str]]:
+        cats: dict[str, list[str]] = {}
+        mapping = {
+            "tag_string_artist": "Artist",
+            "tag_string_character": "Character",
+            "tag_string_copyright": "Copyright",
+            "tag_string_general": "General",
+            "tag_string_meta": "Meta",
+        }
+        for key, label in mapping.items():
+            val = item.get(key, "")
+            if val and val.strip():
+                cats[label] = val.split()
+        return cats

booru_viewer/core/api/e621.py

@@ -67,6 +67,7 @@ class E621Client(BooruClient):
                     source=self._get_source(item),
                     width=self._get_nested(item, "file", "width") or 0,
                     height=self._get_nested(item, "file", "height") or 0,
+                    tag_categories=self._extract_tag_categories(item),
                 )
             )
         return posts
@@ -156,6 +157,23 @@ class E621Client(BooruClient):
             return tags_obj
         return ""
 
+    @staticmethod
+    def _extract_tag_categories(item: dict) -> dict[str, list[str]]:
+        tags_obj = item.get("tags")
+        if not isinstance(tags_obj, dict):
+            return {}
+        cats: dict[str, list[str]] = {}
+        mapping = {
+            "artist": "Artist", "character": "Character",
+            "copyright": "Copyright", "species": "Species",
+            "general": "General", "meta": "Meta", "lore": "Lore",
+        }
+        for key, label in mapping.items():
+            tag_list = tags_obj.get(key, [])
+            if isinstance(tag_list, list) and tag_list:
+                cats[label] = tag_list
+        return cats
+
     @staticmethod
     def _get_score(item: dict) -> int:
         """e621 score is a dict with up/down/total."""

booru_viewer/gui/app.py

@@ -136,16 +136,50 @@ class InfoPanel(QWidget):
             item = self._tags_flow.takeAt(0)
             if item.widget():
                 item.widget().deleteLater()
-        # Add clickable tags
-        for tag in post.tag_list[:100]:
-            btn = QPushButton(tag)
-            btn.setFlat(True)
-            btn.setCursor(Qt.CursorShape.PointingHandCursor)
-            btn.setStyleSheet(
-                "QPushButton { text-align: left; padding: 1px 4px; border: none; }"
-            )
-            btn.clicked.connect(lambda checked, t=tag: self.tag_clicked.emit(t))
-            self._tags_flow.addWidget(btn)
+
+        # Tag category colors
+        _CAT_COLORS = {
+            "Artist": "#f2ac08",
+            "Character": "#0a0",
+            "Copyright": "#c0f",
+            "Species": "#e44",
+            "General": "",
+            "Meta": "#888",
+            "Lore": "#888",
+        }
+
+        if post.tag_categories:
+            # Display tags grouped by category
+            for category, tags in post.tag_categories.items():
+                color = _CAT_COLORS.get(category, "")
+                header = QLabel(f"{category}:")
+                header.setStyleSheet(
+                    f"font-weight: bold; margin-top: 6px; margin-bottom: 2px;"
+                    + (f" color: {color};" if color else "")
+                )
+                self._tags_flow.addWidget(header)
+                for tag in tags[:50]:
+                    btn = QPushButton(tag)
+                    btn.setFlat(True)
+                    btn.setCursor(Qt.CursorShape.PointingHandCursor)
+                    style = "QPushButton { text-align: left; padding: 1px 4px; border: none;"
+                    if color:
+                        style += f" color: {color};"
+                    style += " }"
+                    btn.setStyleSheet(style)
+                    btn.clicked.connect(lambda checked, t=tag: self.tag_clicked.emit(t))
+                    self._tags_flow.addWidget(btn)
+        else:
+            # Fallback: flat tag list (Gelbooru, Moebooru)
+            for tag in post.tag_list[:100]:
+                btn = QPushButton(tag)
+                btn.setFlat(True)
+                btn.setCursor(Qt.CursorShape.PointingHandCursor)
+                btn.setStyleSheet(
+                    "QPushButton { text-align: left; padding: 1px 4px; border: none; }"
+                )
+                btn.clicked.connect(lambda checked, t=tag: self.tag_clicked.emit(t))
+                self._tags_flow.addWidget(btn)
         self._tags_flow.addStretch()
 
     def clear(self) -> None: