feat: implement email keyword management with color tagging

- Introduced a new settings section for managing email keywords (labels/tags) with associated colors.
- Updated email context menu, viewer, and list item components to support the new keyword system.
- Refactored color tag handling to accommodate both new $label: and legacy $color: prefixes.
- Added utility functions for retrieving email color tags based on keywords.
- Enhanced localization files to include translations for the new keyword management features.
- Updated the settings store to manage keyword definitions, including add, update, delete, and reorder functionalities.
- Added tests for the new keyword handling logic.

app/[locale]/page.tsx

@@ -532,22 +532,22 @@ export default function Home() {
     if (!client) return;
 
     try {
-      // Remove any existing color tags
+      // Remove any existing label/color tags
       const email = emails.find(e => e.id === emailId);
       if (!email) return;
 
       const keywords = { ...email.keywords };
 
-      // Remove old color tags - set to false for JMAP to remove them
+      // Remove old label and legacy color tags - set to false for JMAP to remove them
       Object.keys(keywords).forEach(key => {
-        if (key.startsWith("$color:")) {
+        if (key.startsWith("$label:") || key.startsWith("$color:")) {
           keywords[key] = false;
         }
       });
 
-      // Add new color tag if specified
+      // Add new label tag if specified (using new $label: prefix)
       if (color) {
-        keywords[`$color:${color}`] = true;
+        keywords[`$label:${color}`] = true;
       }
 
       // Update email keywords via JMAP

app/[locale]/settings/page.tsx

@@ -15,11 +15,12 @@ import { FilterSettings } from '@/components/settings/filter-settings';
 import { TemplateSettings } from '@/components/settings/template-settings';
 import { AdvancedSettings } from '@/components/settings/advanced-settings';
 import { FolderSettings } from '@/components/settings/folder-settings';
+import { KeywordSettings } from '@/components/settings/keyword-settings';
 import { useAuthStore } from '@/stores/auth-store';
 import { useIsDesktop } from '@/hooks/use-media-query';
 import { cn } from '@/lib/utils';
 
-type Tab = 'appearance' | 'email' | 'account' | 'identities' | 'vacation' | 'calendar' | 'filters' | 'templates' | 'folders' | 'advanced';
+type Tab = 'appearance' | 'email' | 'account' | 'identities' | 'vacation' | 'calendar' | 'filters' | 'templates' | 'folders' | 'keywords' | 'advanced';
 
 export default function SettingsPage() {
   const router = useRouter();
@@ -53,6 +54,7 @@ export default function SettingsPage() {
     ...(supportsSieve ? [{ id: 'filters' as Tab, label: t('tabs.filters') }] : []),
     { id: 'templates', label: t('tabs.templates') },
     { id: 'folders', label: t('tabs.folders') },
+    { id: 'keywords', label: t('tabs.keywords') },
     { id: 'advanced', label: t('tabs.advanced') },
   ];
 
@@ -76,6 +78,7 @@ export default function SettingsPage() {
       {activeTab === 'filters' && <FilterSettings />}
       {activeTab === 'templates' && <TemplateSettings />}
       {activeTab === 'folders' && <FolderSettings />}
+      {activeTab === 'keywords' && <KeywordSettings />}
       {activeTab === 'advanced' && <AdvancedSettings />}
     </>
   );

components/email/email-context-menu.tsx

@@ -19,7 +19,7 @@ import {
   Trash2,
   Archive,
   FolderInput,
-  Palette,
+  Tag,
   X,
   Inbox,
   Send,
@@ -29,6 +29,7 @@ import {
   ShieldCheck,
 } from "lucide-react";
 import { cn } from "@/lib/utils";
+import { useSettingsStore, KEYWORD_PALETTE } from "@/stores/settings-store";
 
 interface Position {
   x: number;
@@ -84,12 +85,14 @@ const getMailboxIcon = (role?: string) => {
   }
 };
 
-// Get current color from email keywords
+// Get current label/color from email keywords (supports both $label: and legacy $color:)
 const getCurrentColor = (keywords: Record<string, boolean> | undefined) => {
   if (!keywords) return null;
   for (const key of Object.keys(keywords)) {
-    if (key.startsWith("$color:") && keywords[key] === true) {
+    if ((key.startsWith("$label:") || key.startsWith("$color:")) && keywords[key] === true) {
-      return key.replace("$color:", "");
+      return key.startsWith("$label:")
+        ? key.slice("$label:".length)
+        : key.slice("$color:".length);
     }
   }
   return null;
@@ -125,22 +128,19 @@ export function EmailContextMenu({
 }: EmailContextMenuProps) {
   const t = useTranslations("context_menu");
   const tColor = useTranslations("email_viewer.color_tag");
+  const emailKeywords = useSettingsStore((state) => state.emailKeywords);
   const isUnread = !email.keywords?.$seen;
   const isStarred = email.keywords?.$flagged;
   const currentColor = getCurrentColor(email.keywords);
   const showBatchActions = isMultiSelect && selectedCount > 1;
   const isInJunkFolder = currentMailboxRole === 'junk';
 
-  // Color options for email tags (using translations)
+  // Build color options from keyword definitions in settings
-  const colorOptions = [
+  const colorOptions = emailKeywords.map((kw) => ({
-    { name: tColor("red"), value: "red", color: "bg-red-500" },
+    name: kw.label,
-    { name: tColor("orange"), value: "orange", color: "bg-orange-500" },
+    value: kw.id,
-    { name: tColor("yellow"), value: "yellow", color: "bg-yellow-500" },
+    color: KEYWORD_PALETTE[kw.color]?.dot || "bg-gray-500",
-    { name: tColor("green"), value: "green", color: "bg-green-500" },
+  }));
-    { name: tColor("blue"), value: "blue", color: "bg-blue-500" },
-    { name: tColor("purple"), value: "purple", color: "bg-purple-500" },
-    { name: tColor("pink"), value: "pink", color: "bg-pink-500" },
-  ];
 
   // Filter mailboxes for move-to submenu (exclude current, drafts, virtual nodes)
   const moveTargets = mailboxes.filter(
@@ -272,7 +272,7 @@ export function EmailContextMenu({
 
       {/* Set color submenu - only for single email */}
       {!showBatchActions && (
-        <ContextMenuSubMenu icon={Palette} label={t("color_tag")}>
+        <ContextMenuSubMenu icon={Tag} label={t("color_tag")}>
           <div
             className="px-3 py-2 flex flex-wrap gap-2"
             role="group"

components/email/email-list-item.tsx

@@ -7,10 +7,11 @@ import { cn } from "@/lib/utils";
 import { Avatar } from "@/components/ui/avatar";
 import { Paperclip, Star, Circle, CheckSquare, Square } from "lucide-react";
 import { useEmailStore } from "@/stores/email-store";
-import { useSettingsStore } from "@/stores/settings-store";
+import { useSettingsStore, KEYWORD_PALETTE } from "@/stores/settings-store";
 import { useAuthStore } from "@/stores/auth-store";
 import { useEmailDrag } from "@/hooks/use-email-drag";
 import { EmailIdentityBadge } from "./email-identity-badge";
+import { getEmailColorTag } from "@/lib/thread-utils";
 
 interface EmailListItemProps {
   email: Email;
@@ -19,39 +20,22 @@ interface EmailListItemProps {
   onContextMenu?: (e: React.MouseEvent, email: Email) => void;
 }
 
-// Color tag mapping - using lighter backgrounds for better readability
-const colorTags = {
-  red: "bg-red-50 dark:bg-red-950/30",
-  orange: "bg-orange-50 dark:bg-orange-950/30",
-  yellow: "bg-yellow-50 dark:bg-yellow-950/30",
-  green: "bg-green-50 dark:bg-green-950/30",
-  blue: "bg-blue-50 dark:bg-blue-950/30",
-  purple: "bg-purple-50 dark:bg-purple-950/30",
-  pink: "bg-pink-50 dark:bg-pink-950/30",
-} as const;
-
-const getEmailColor = (keywords: Record<string, boolean> | undefined) => {
-  if (!keywords) return null;
-  for (const key of Object.keys(keywords)) {
-    if (key.startsWith("$color:") && keywords[key] === true) {
-      const color = key.replace("$color:", "");
-      return colorTags[color as keyof typeof colorTags] || null;
-    }
-  }
-  return null;
-};
-
 export function EmailListItem({ email, selected, onClick, onContextMenu }: EmailListItemProps) {
   const t = useTranslations('email_viewer');
   const { selectedEmailIds, toggleEmailSelection, selectRangeEmails, selectedMailbox } = useEmailStore();
   const showPreview = useSettingsStore((state) => state.showPreview);
+  const emailKeywords = useSettingsStore((state) => state.emailKeywords);
   const { identities } = useAuthStore();
   const isChecked = selectedEmailIds.has(email.id);
   const isUnread = !email.keywords?.$seen;
   const isStarred = email.keywords?.$flagged;
   const isImportant = email.keywords?.["$important"];
   const sender = email.from?.[0];
-  const colorTag = getEmailColor(email.keywords);
+
+  // Resolve color tag using keyword definitions from settings
+  const colorTagId = getEmailColorTag(email.keywords);
+  const keywordDef = colorTagId ? emailKeywords.find(k => k.id === colorTagId) : null;
+  const colorTag = keywordDef ? KEYWORD_PALETTE[keywordDef.color]?.bg ?? null : null;
 
   // Drag and drop functionality
   const { dragHandlers, isDragging } = useEmailDrag({

components/email/email-viewer.tsx

@@ -50,7 +50,7 @@ import {
   Keyboard,
 } from "lucide-react";
 import { useTranslations } from "next-intl";
-import { useSettingsStore } from "@/stores/settings-store";
+import { useSettingsStore, KEYWORD_PALETTE } from "@/stores/settings-store";
 import { useUIStore } from "@/stores/ui-store";
 import { useDeviceDetection } from "@/hooks/use-media-query";
 import { useAuthStore } from "@/stores/auth-store";
@@ -113,8 +113,10 @@ const getFileIcon = (name?: string, type?: string) => {
 const getCurrentColor = (keywords: Record<string, boolean> | undefined) => {
   if (!keywords) return null;
   for (const key of Object.keys(keywords)) {
-    if (key.startsWith("$color:") && keywords[key] === true) {
+    if ((key.startsWith("$label:") || key.startsWith("$color:")) && keywords[key] === true) {
-      return key.replace("$color:", "");
+      return key.startsWith("$label:")
+        ? key.slice("$label:".length)
+        : key.slice("$color:".length);
     }
   }
   return null;
@@ -184,20 +186,17 @@ export function EmailViewer({
   const externalContentPolicy = useSettingsStore((state) => state.externalContentPolicy);
   const addTrustedSender = useSettingsStore((state) => state.addTrustedSender);
   const isSenderTrusted = useSettingsStore((state) => state.isSenderTrusted);
+  const emailKeywords = useSettingsStore((state) => state.emailKeywords);
 
   // Detect if current mailbox is Junk folder
   const isInJunkFolder = currentMailboxRole === 'junk';
 
-  // Color options for email tags (using translations)
+  // Color options for email tags (from user-defined keyword settings)
-  const colorOptions = [
+  const colorOptions = emailKeywords.map((kw) => ({
-    { name: t("color_tag.red"), value: "red", color: "bg-red-500" },
+    name: kw.label,
-    { name: t("color_tag.orange"), value: "orange", color: "bg-orange-500" },
+    value: kw.id,
-    { name: t("color_tag.yellow"), value: "yellow", color: "bg-yellow-500" },
+    color: KEYWORD_PALETTE[kw.color]?.dot || 'bg-gray-500',
-    { name: t("color_tag.green"), value: "green", color: "bg-green-500" },
+  }));
-    { name: t("color_tag.blue"), value: "blue", color: "bg-blue-500" },
-    { name: t("color_tag.purple"), value: "purple", color: "bg-purple-500" },
-    { name: t("color_tag.pink"), value: "pink", color: "bg-pink-500" },
-  ];
 
   // Tablet list visibility
   const { isTablet } = useDeviceDetection();
@@ -804,17 +803,13 @@ export function EmailViewer({
                   className="h-8 w-8 rounded hover:bg-muted flex items-center justify-center"
                   title={t('set_color')}
                 >
-                  <Circle className={cn(
+                  {(() => {
-                    "w-4 h-4",
+                    const kw = currentColor ? emailKeywords.find(k => k.id === currentColor) : null;
-                    currentColor === 'red' && "fill-red-500 text-red-500",
+                    const dotClass = kw ? KEYWORD_PALETTE[kw.color]?.dot : null;
-                    currentColor === 'orange' && "fill-orange-500 text-orange-500",
+                    return dotClass
-                    currentColor === 'yellow' && "fill-yellow-500 text-yellow-500",
+                      ? <div className={cn("w-4 h-4 rounded-full", dotClass)} />
-                    currentColor === 'green' && "fill-green-500 text-green-500",
+                      : <Circle className="w-4 h-4 text-gray-400" />;
-                    currentColor === 'blue' && "fill-blue-500 text-blue-500",
+                  })()}
-                    currentColor === 'purple' && "fill-purple-500 text-purple-500",
-                    currentColor === 'pink' && "fill-pink-500 text-pink-500",
-                    !currentColor && "text-gray-400"
-                  )} />
                 </button>
 
                 {/* Colors appear on hover */}

components/email/thread-list-item.tsx

@@ -6,10 +6,10 @@ import { Email, ThreadGroup } from "@/lib/jmap/types";
 import { cn } from "@/lib/utils";
 import { Avatar } from "@/components/ui/avatar";
 import { Paperclip, Star, Circle, ChevronRight, ChevronDown, Loader2, MessageSquare } from "lucide-react";
-import { useSettingsStore } from "@/stores/settings-store";
+import { useSettingsStore, KEYWORD_PALETTE } from "@/stores/settings-store";
 import { useUIStore } from "@/stores/ui-store";
 import { useEmailStore } from "@/stores/email-store";
-import { getThreadColorTag } from "@/lib/thread-utils";
+import { getThreadColorTag, getEmailColorTag } from "@/lib/thread-utils";
 import { useEmailDrag } from "@/hooks/use-email-drag";
 import { ThreadEmailItem } from "./thread-email-item";
 import { useTranslations } from "next-intl";
@@ -26,16 +26,6 @@ interface ThreadListItemProps {
   onOpenConversation?: (thread: ThreadGroup) => void;
 }
 
-const colorTags = {
-  red: "bg-red-50 dark:bg-red-950/30",
-  orange: "bg-orange-50 dark:bg-orange-950/30",
-  yellow: "bg-yellow-50 dark:bg-yellow-950/30",
-  green: "bg-green-50 dark:bg-green-950/30",
-  blue: "bg-blue-50 dark:bg-blue-950/30",
-  purple: "bg-purple-50 dark:bg-purple-950/30",
-  pink: "bg-pink-50 dark:bg-pink-950/30",
-} as const;
-
 interface SingleEmailItemProps {
   email: Email;
   selected: boolean;
@@ -51,8 +41,17 @@ const SingleEmailItem = React.forwardRef<HTMLDivElement, SingleEmailItemProps>(
     const isStarred = email.keywords?.$flagged;
     const sender = email.from?.[0];
     const { selectedMailbox, selectedEmailIds, toggleEmailSelection, selectRangeEmails } = useEmailStore();
+    const emailKeywords = useSettingsStore((state) => state.emailKeywords);
     const isChecked = selectedEmailIds.has(email.id);
 
+    // Resolve color from keyword definitions if not passed directly
+    const resolvedColorTag = (() => {
+      if (colorTag) return colorTag;
+      const tagId = getEmailColorTag(email.keywords);
+      const kw = tagId ? emailKeywords.find(k => k.id === tagId) : null;
+      return kw ? KEYWORD_PALETTE[kw.color]?.bg ?? null : null;
+    })();
+
     const { dragHandlers, isDragging } = useEmailDrag({
       email,
       sourceMailboxId: selectedMailbox,
@@ -80,15 +79,15 @@ const SingleEmailItem = React.forwardRef<HTMLDivElement, SingleEmailItemProps>(
         {...dragHandlers}
         className={cn(
           "relative group cursor-pointer transition-all duration-200 border-b border-border",
-          colorTag ? colorTag : (
+          resolvedColorTag ? resolvedColorTag : (
             selected
               ? "bg-accent"
               : "bg-background"
           ),
-          selected && !colorTag && "shadow-sm",
+          selected && !resolvedColorTag && "shadow-sm",
-          !colorTag && !selected && "hover:bg-muted hover:shadow-sm",
+          !resolvedColorTag && !selected && "hover:bg-muted hover:shadow-sm",
-          colorTag && "hover:brightness-95 dark:hover:brightness-110",
+          resolvedColorTag && "hover:brightness-95 dark:hover:brightness-110",
-          isUnread && !colorTag && "bg-accent/30",
+          isUnread && !resolvedColorTag && "bg-accent/30",
           isChecked && "ring-2 ring-primary/20 bg-accent/40",
           isDragging && "opacity-50 scale-[0.98] ring-2 ring-primary/30"
         )}
@@ -192,7 +191,9 @@ export const ThreadListItem = React.forwardRef<HTMLDivElement, ThreadListItemPro
     });
 
     const threadColor = getThreadColorTag(thread.emails);
-    const colorTag = threadColor ? colorTags[threadColor as keyof typeof colorTags] : null;
+    const emailKeywordDefs = useSettingsStore((state) => state.emailKeywords);
+    const keywordDef = threadColor ? emailKeywordDefs.find(k => k.id === threadColor) : null;
+    const colorTag = keywordDef ? KEYWORD_PALETTE[keywordDef.color]?.bg ?? null : null;
 
     const isSelected = selectedEmailId === latestEmail.id ||
       thread.emails.some(e => e.id === selectedEmailId);

components/settings/keyword-settings.tsx

@@ -0,0 +1,244 @@
+"use client";
+
+import { useState } from "react";
+import { useTranslations } from "next-intl";
+import { useSettingsStore, KEYWORD_PALETTE, DEFAULT_KEYWORDS, type KeywordDefinition } from "@/stores/settings-store";
+import { SettingsSection } from "./settings-section";
+import { Plus, Pencil, Trash2, GripVertical, Check, X, RotateCcw } from "lucide-react";
+import { cn } from "@/lib/utils";
+
+const PALETTE_KEYS = Object.keys(KEYWORD_PALETTE);
+
+function KeywordColorPicker({
+  value,
+  onChange,
+}: {
+  value: string;
+  onChange: (color: string) => void;
+}) {
+  return (
+    <div className="flex flex-wrap gap-1.5">
+      {PALETTE_KEYS.map((colorKey) => (
+        <button
+          key={colorKey}
+          type="button"
+          onClick={() => onChange(colorKey)}
+          className={cn(
+            "w-6 h-6 rounded-full transition-transform hover:scale-110 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2",
+            KEYWORD_PALETTE[colorKey].dot,
+            value === colorKey && "ring-2 ring-offset-2 ring-offset-background ring-foreground"
+          )}
+          aria-label={colorKey}
+        />
+      ))}
+    </div>
+  );
+}
+
+function KeywordRow({
+  keyword,
+  onEdit,
+  onDelete,
+}: {
+  keyword: KeywordDefinition;
+  onEdit: () => void;
+  onDelete: () => void;
+}) {
+  const t = useTranslations("settings.keywords");
+  const palette = KEYWORD_PALETTE[keyword.color];
+
+  return (
+    <div className="flex items-center gap-3 py-2.5 px-3 rounded-md border border-border bg-background group">
+      <GripVertical className="w-4 h-4 text-muted-foreground opacity-0 group-hover:opacity-50 cursor-grab" />
+      <div className={cn("w-5 h-5 rounded-full shrink-0", palette?.dot || "bg-gray-500")} />
+      <span className="flex-1 text-sm font-medium truncate">{keyword.label}</span>
+      <span className="text-xs text-muted-foreground font-mono">{"$label:" + keyword.id}</span>
+      <div className="flex items-center gap-1 opacity-0 group-hover:opacity-100 transition-opacity">
+        <button
+          type="button"
+          onClick={onEdit}
+          className="p-1.5 rounded-md hover:bg-muted text-muted-foreground hover:text-foreground transition-colors"
+          title={t("edit")}
+        >
+          <Pencil className="w-3.5 h-3.5" />
+        </button>
+        <button
+          type="button"
+          onClick={onDelete}
+          className="p-1.5 rounded-md hover:bg-destructive/10 text-muted-foreground hover:text-destructive transition-colors"
+          title={t("delete")}
+        >
+          <Trash2 className="w-3.5 h-3.5" />
+        </button>
+      </div>
+    </div>
+  );
+}
+
+function KeywordEditForm({
+  initial,
+  existingIds,
+  onSave,
+  onCancel,
+}: {
+  initial?: KeywordDefinition;
+  existingIds: string[];
+  onSave: (keyword: KeywordDefinition) => void;
+  onCancel: () => void;
+}) {
+  const t = useTranslations("settings.keywords");
+  const [label, setLabel] = useState(initial?.label || "");
+  const [color, setColor] = useState(initial?.color || "blue");
+  const isEditing = !!initial;
+
+  const normalizedId = isEditing
+    ? initial.id
+    : label
+        .trim()
+        .toLowerCase()
+        .replace(/[^a-z0-9_-]/g, "-")
+        .replace(/-+/g, "-")
+        .replace(/^-|-$/g, "");
+
+  const isDuplicate = !isEditing && normalizedId.length > 0 && existingIds.includes(normalizedId);
+  const isValid = normalizedId.length > 0 && label.trim().length > 0 && !isDuplicate;
+
+  const handleSave = () => {
+    if (!isValid) return;
+    onSave({ id: normalizedId, label: label.trim(), color });
+  };
+
+  return (
+    <div className="space-y-3 p-3 rounded-md border border-primary/30 bg-accent/30">
+      <div>
+        <label className="text-xs font-medium text-muted-foreground mb-1 block">
+          {t("label_field")}
+        </label>
+        <input
+          type="text"
+          value={label}
+          onChange={(e) => setLabel(e.target.value)}
+          className="w-full px-2.5 py-1.5 text-sm rounded-md border border-border bg-background focus:outline-none focus:ring-2 focus:ring-ring"
+          placeholder={t("label_placeholder")}
+          autoFocus
+          maxLength={30}
+          onKeyDown={(e) => e.key === "Enter" && handleSave()}
+        />
+        {isDuplicate && (
+          <p className="text-xs text-destructive mt-1">{t("id_exists")}</p>
+        )}
+      </div>
+      <div>
+        <label className="text-xs font-medium text-muted-foreground mb-1.5 block">
+          {t("color_field")}
+        </label>
+        <KeywordColorPicker value={color} onChange={setColor} />
+      </div>
+      <div className="flex items-center gap-2 justify-end">
+        <button
+          type="button"
+          onClick={onCancel}
+          className="flex items-center gap-1.5 px-3 py-1.5 text-xs rounded-md border border-border hover:bg-muted transition-colors"
+        >
+          <X className="w-3.5 h-3.5" />
+          {t("cancel")}
+        </button>
+        <button
+          type="button"
+          onClick={handleSave}
+          disabled={!isValid}
+          className="flex items-center gap-1.5 px-3 py-1.5 text-xs rounded-md bg-primary text-primary-foreground hover:bg-primary/90 transition-colors disabled:opacity-50"
+        >
+          <Check className="w-3.5 h-3.5" />
+          {isEditing ? t("save") : t("add")}
+        </button>
+      </div>
+    </div>
+  );
+}
+
+export function KeywordSettings() {
+  const t = useTranslations("settings.keywords");
+  const { emailKeywords, addKeyword, updateKeyword, removeKeyword, reorderKeywords } =
+    useSettingsStore();
+  const [editingId, setEditingId] = useState<string | null>(null);
+  const [isAdding, setIsAdding] = useState(false);
+
+  const existingIds = emailKeywords.map((k) => k.id);
+
+  const handleAdd = (keyword: KeywordDefinition) => {
+    addKeyword(keyword);
+    setIsAdding(false);
+  };
+
+  const handleEdit = (keyword: KeywordDefinition) => {
+    updateKeyword(keyword.id, { label: keyword.label, color: keyword.color });
+    setEditingId(null);
+  };
+
+  const handleDelete = (id: string) => {
+    removeKeyword(id);
+  };
+
+  const handleResetDefaults = () => {
+    reorderKeywords(DEFAULT_KEYWORDS);
+  };
+
+  return (
+    <SettingsSection title={t("title")} description={t("description")}>
+      <div className="space-y-2">
+        {emailKeywords.map((keyword) =>
+          editingId === keyword.id ? (
+            <KeywordEditForm
+              key={keyword.id}
+              initial={keyword}
+              existingIds={existingIds.filter((id) => id !== keyword.id)}
+              onSave={handleEdit}
+              onCancel={() => setEditingId(null)}
+            />
+          ) : (
+            <KeywordRow
+              key={keyword.id}
+              keyword={keyword}
+              onEdit={() => {
+                setEditingId(keyword.id);
+                setIsAdding(false);
+              }}
+              onDelete={() => handleDelete(keyword.id)}
+            />
+          )
+        )}
+
+        {isAdding ? (
+          <KeywordEditForm
+            existingIds={existingIds}
+            onSave={handleAdd}
+            onCancel={() => setIsAdding(false)}
+          />
+        ) : (
+          <div className="flex items-center gap-2 pt-1">
+            <button
+              type="button"
+              onClick={() => {
+                setIsAdding(true);
+                setEditingId(null);
+              }}
+              className="flex items-center gap-1.5 px-3 py-1.5 text-xs rounded-md border border-dashed border-border hover:border-primary hover:bg-accent transition-colors text-muted-foreground hover:text-foreground"
+            >
+              <Plus className="w-3.5 h-3.5" />
+              {t("add_keyword")}
+            </button>
+            <button
+              type="button"
+              onClick={handleResetDefaults}
+              className="flex items-center gap-1.5 px-3 py-1.5 text-xs rounded-md border border-border hover:bg-muted transition-colors text-muted-foreground hover:text-foreground"
+            >
+              <RotateCcw className="w-3.5 h-3.5" />
+              {t("reset_defaults")}
+            </button>
+          </div>
+        )}
+      </div>
+    </SettingsSection>
+  );
+}

lib/__tests__/thread-utils.test.ts

@@ -210,7 +210,11 @@ describe('mergeThreadEmails', () => {
 });
 
 describe('getEmailColorTag', () => {
-  it('returns color from $color: keyword', () => {
+  it('returns label from $label: keyword', () => {
+    expect(getEmailColorTag({ '$label:red': true, $seen: true })).toBe('red');
+  });
+
+  it('returns label from legacy $color: keyword', () => {
     expect(getEmailColorTag({ '$color:red': true, $seen: true })).toBe('red');
   });
 
@@ -227,7 +231,7 @@ describe('getThreadColorTag', () => {
   it('returns first color found across thread emails', () => {
     const emails = [
       makeEmail({ id: 'e1', keywords: { $seen: true } }),
-      makeEmail({ id: 'e2', keywords: { '$color:blue': true } }),
+      makeEmail({ id: 'e2', keywords: { '$label:blue': true } }),
     ];
     expect(getThreadColorTag(emails)).toBe('blue');
   });

lib/thread-utils.ts

@@ -136,15 +136,23 @@ export function mergeThreadEmails(
   };
 }
 
+/** Active prefix for new keyword tags written to JMAP */
+export const KEYWORD_PREFIX = "$label:";
+/** Legacy prefix still recognised when reading */
+export const KEYWORD_PREFIX_LEGACY = "$color:";
+
 /**
- * Gets color tag from email keywords (if any).
+ * Gets label/color tag from email keywords (if any).
+ * Reads both the current $label: prefix and the legacy $color: prefix.
  */
 export function getEmailColorTag(keywords: Record<string, boolean> | undefined): string | null {
   if (!keywords) return null;
 
   for (const key of Object.keys(keywords)) {
-    if (key.startsWith("$color:") && keywords[key] === true) {
+    if ((key.startsWith(KEYWORD_PREFIX) || key.startsWith(KEYWORD_PREFIX_LEGACY)) && keywords[key] === true) {
-      return key.replace("$color:", "");
+      return key.startsWith(KEYWORD_PREFIX)
+        ? key.slice(KEYWORD_PREFIX.length)
+        : key.slice(KEYWORD_PREFIX_LEGACY.length);
     }
   }
 

locales/de/common.json

@@ -447,7 +447,8 @@
       "calendar": "Kalender",
       "filters": "Filter",
       "templates": "Vorlagen",
-      "folders": "Ordner"
+      "folders": "Ordner",
+      "keywords": "Schlüsselwörter"
     },
     "tab_groups": {
       "general": "Allgemein",
@@ -487,6 +488,23 @@
         "description": "Weiche Übergänge und Effekte anzeigen"
       }
     },
+    "keywords": {
+      "title": "E-Mail-Schlüsselwörter",
+      "description": "Definieren Sie Schlüsselwörter (Labels/Tags) zum Organisieren Ihrer E-Mails mit Farben.",
+      "add_keyword": "Schlüsselwort hinzufügen",
+      "reset_defaults": "Auf Standard zurücksetzen",
+      "label_field": "Anzeigename",
+      "label_placeholder": "z.B. Arbeit, Privat, Dringend",
+      "id_field": "Schlüsselwort-ID",
+      "id_placeholder": "z.B. arbeit, privat",
+      "color_field": "Farbe",
+      "id_exists": "Diese Schlüsselwort-ID existiert bereits",
+      "edit": "Schlüsselwort bearbeiten",
+      "delete": "Schlüsselwort löschen",
+      "save": "Speichern",
+      "add": "Hinzufügen",
+      "cancel": "Abbrechen"
+    },
     "language_region": {
       "title": "Sprache & Region",
       "description": "Konfigurieren Sie Sprach- und Regionaleinstellungen",

locales/en/common.json

@@ -459,7 +459,8 @@
       "calendar": "Calendar",
       "filters": "Filters",
       "templates": "Templates",
-      "folders": "Folders"
+      "folders": "Folders",
+      "keywords": "Keywords"
     },
     "tab_groups": {
       "general": "General",
@@ -499,6 +500,23 @@
         "description": "Show smooth transitions and effects"
       }
     },
+    "keywords": {
+      "title": "Email Keywords",
+      "description": "Define keywords (labels/tags) to organize your emails with colors. These are stored as JMAP keywords on the server.",
+      "add_keyword": "Add Keyword",
+      "reset_defaults": "Reset to Defaults",
+      "label_field": "Display Name",
+      "label_placeholder": "e.g. Work, Personal, Urgent",
+      "id_field": "Keyword ID",
+      "id_placeholder": "e.g. work, personal",
+      "color_field": "Color",
+      "id_exists": "This keyword ID already exists",
+      "edit": "Edit keyword",
+      "delete": "Delete keyword",
+      "save": "Save",
+      "add": "Add",
+      "cancel": "Cancel"
+    },
     "language_region": {
       "title": "Language & Region",
       "description": "Configure language and regional preferences",

locales/es/common.json

@@ -447,7 +447,8 @@
       "calendar": "Calendario",
       "filters": "Filtros",
       "templates": "Plantillas",
-      "folders": "Carpetas"
+      "folders": "Carpetas",
+      "keywords": "Palabras clave"
     },
     "tab_groups": {
       "general": "General",
@@ -487,6 +488,23 @@
         "description": "Mostrar transiciones y efectos suaves"
       }
     },
+    "keywords": {
+      "title": "Palabras clave de correo",
+      "description": "Define palabras clave (etiquetas) para organizar tus correos con colores.",
+      "add_keyword": "Añadir palabra clave",
+      "reset_defaults": "Restablecer valores predeterminados",
+      "label_field": "Nombre para mostrar",
+      "label_placeholder": "ej. Trabajo, Personal, Urgente",
+      "id_field": "ID de palabra clave",
+      "id_placeholder": "ej. trabajo, personal",
+      "color_field": "Color",
+      "id_exists": "Esta ID de palabra clave ya existe",
+      "edit": "Editar palabra clave",
+      "delete": "Eliminar palabra clave",
+      "save": "Guardar",
+      "add": "Añadir",
+      "cancel": "Cancelar"
+    },
     "language_region": {
       "title": "Idioma y Región",
       "description": "Configure las preferencias de idioma y región",

locales/fr/common.json

@@ -447,7 +447,8 @@
       "calendar": "Calendrier",
       "filters": "Filtres",
       "templates": "Modèles",
-      "folders": "Dossiers"
+      "folders": "Dossiers",
+      "keywords": "Mots-clés"
     },
     "tab_groups": {
       "general": "Général",
@@ -487,6 +488,23 @@
         "description": "Afficher les transitions et effets fluides"
       }
     },
+    "keywords": {
+      "title": "Mots-clés des e-mails",
+      "description": "Définissez des mots-clés (étiquettes) pour organiser vos e-mails avec des couleurs.",
+      "add_keyword": "Ajouter un mot-clé",
+      "reset_defaults": "Réinitialiser par défaut",
+      "label_field": "Nom d'affichage",
+      "label_placeholder": "ex. Travail, Personnel, Urgent",
+      "id_field": "ID du mot-clé",
+      "id_placeholder": "ex. travail, personnel",
+      "color_field": "Couleur",
+      "id_exists": "Cet ID de mot-clé existe déjà",
+      "edit": "Modifier le mot-clé",
+      "delete": "Supprimer le mot-clé",
+      "save": "Enregistrer",
+      "add": "Ajouter",
+      "cancel": "Annuler"
+    },
     "language_region": {
       "title": "Langue et région",
       "description": "Configurez vos préférences linguistiques et régionales",

locales/it/common.json

@@ -447,7 +447,8 @@
       "calendar": "Calendario",
       "filters": "Filtri",
       "templates": "Modelli",
-      "folders": "Cartelle"
+      "folders": "Cartelle",
+      "keywords": "Parole chiave"
     },
     "tab_groups": {
       "general": "Generale",
@@ -487,6 +488,23 @@
         "description": "Mostra transizioni ed effetti fluidi"
       }
     },
+    "keywords": {
+      "title": "Parole chiave e-mail",
+      "description": "Definisci parole chiave (etichette) per organizzare le tue e-mail con colori.",
+      "add_keyword": "Aggiungi parola chiave",
+      "reset_defaults": "Ripristina predefiniti",
+      "label_field": "Nome visualizzato",
+      "label_placeholder": "es. Lavoro, Personale, Urgente",
+      "id_field": "ID parola chiave",
+      "id_placeholder": "es. lavoro, personale",
+      "color_field": "Colore",
+      "id_exists": "Questo ID parola chiave esiste già",
+      "edit": "Modifica parola chiave",
+      "delete": "Elimina parola chiave",
+      "save": "Salva",
+      "add": "Aggiungi",
+      "cancel": "Annulla"
+    },
     "language_region": {
       "title": "Lingua e regione",
       "description": "Configura le preferenze di lingua e regionali",

locales/ja/common.json

@@ -447,7 +447,8 @@
       "calendar": "カレンダー",
       "filters": "フィルター",
       "templates": "テンプレート",
-      "folders": "フォルダー"
+      "folders": "フォルダー",
+      "keywords": "キーワード"
     },
     "tab_groups": {
       "general": "一般",
@@ -487,6 +488,23 @@
         "description": "スムーズな遷移とエフェクトを表示"
       }
     },
+    "keywords": {
+      "title": "メールキーワード",
+      "description": "色でメールを整理するためのキーワード（ラベル/タグ）を定義します。",
+      "add_keyword": "キーワードを追加",
+      "reset_defaults": "デフォルトに戻す",
+      "label_field": "表示名",
+      "label_placeholder": "例：仕事、個人、緊急",
+      "id_field": "キーワードID",
+      "id_placeholder": "例：work、personal",
+      "color_field": "色",
+      "id_exists": "このキーワードIDは既に存在します",
+      "edit": "キーワードを編集",
+      "delete": "キーワードを削除",
+      "save": "保存",
+      "add": "追加",
+      "cancel": "キャンセル"
+    },
     "language_region": {
       "title": "言語と地域",
       "description": "言語と地域の設定を構成",

locales/nl/common.json

@@ -447,7 +447,8 @@
       "calendar": "Agenda",
       "filters": "Filters",
       "templates": "Sjablonen",
-      "folders": "Mappen"
+      "folders": "Mappen",
+      "keywords": "Sleutelwoorden"
     },
     "tab_groups": {
       "general": "Algemeen",
@@ -487,6 +488,23 @@
         "description": "Vloeiende overgangen en effecten tonen"
       }
     },
+    "keywords": {
+      "title": "E-mail trefwoorden",
+      "description": "Definieer trefwoorden (labels/tags) om uw e-mails met kleuren te organiseren.",
+      "add_keyword": "Trefwoord toevoegen",
+      "reset_defaults": "Standaardwaarden herstellen",
+      "label_field": "Weergavenaam",
+      "label_placeholder": "bijv. Werk, Persoonlijk, Urgent",
+      "id_field": "Trefwoord-ID",
+      "id_placeholder": "bijv. werk, persoonlijk",
+      "color_field": "Kleur",
+      "id_exists": "Dit trefwoord-ID bestaat al",
+      "edit": "Trefwoord bewerken",
+      "delete": "Trefwoord verwijderen",
+      "save": "Opslaan",
+      "add": "Toevoegen",
+      "cancel": "Annuleren"
+    },
     "language_region": {
       "title": "Taal & Regio",
       "description": "Configureer taal- en regiovoorkeuren",

locales/pt/common.json

@@ -447,7 +447,8 @@
       "calendar": "Calendário",
       "filters": "Filtros",
       "templates": "Modelos",
-      "folders": "Pastas"
+      "folders": "Pastas",
+      "keywords": "Palavras-chave"
     },
     "tab_groups": {
       "general": "Geral",
@@ -487,6 +488,23 @@
         "description": "Mostrar transições e efeitos suaves"
       }
     },
+    "keywords": {
+      "title": "Palavras-chave de e-mail",
+      "description": "Defina palavras-chave (rótulos/tags) para organizar seus e-mails com cores.",
+      "add_keyword": "Adicionar palavra-chave",
+      "reset_defaults": "Restaurar padrões",
+      "label_field": "Nome de exibição",
+      "label_placeholder": "ex. Trabalho, Pessoal, Urgente",
+      "id_field": "ID da palavra-chave",
+      "id_placeholder": "ex. trabalho, pessoal",
+      "color_field": "Cor",
+      "id_exists": "Este ID de palavra-chave já existe",
+      "edit": "Editar palavra-chave",
+      "delete": "Excluir palavra-chave",
+      "save": "Salvar",
+      "add": "Adicionar",
+      "cancel": "Cancelar"
+    },
     "language_region": {
       "title": "Idioma e Região",
       "description": "Configure preferências de idioma e região",

stores/settings-store.ts

@@ -27,6 +27,39 @@ export type TimeFormat = '12h' | '24h';
 export type FirstDayOfWeek = 0 | 1; // 0 = Sunday, 1 = Monday
 export type ExternalContentPolicy = 'ask' | 'block' | 'allow';
 
+export interface KeywordDefinition {
+  id: string;     // Used as JMAP keyword suffix: $label:<id>
+  label: string;  // Display name
+  color: string;  // Key from KEYWORD_PALETTE
+}
+
+// Available color palette for keywords
+export const KEYWORD_PALETTE: Record<string, { dot: string; bg: string }> = {
+  red: { dot: 'bg-red-500', bg: 'bg-red-50 dark:bg-red-950/30' },
+  orange: { dot: 'bg-orange-500', bg: 'bg-orange-50 dark:bg-orange-950/30' },
+  yellow: { dot: 'bg-yellow-500', bg: 'bg-yellow-50 dark:bg-yellow-950/30' },
+  green: { dot: 'bg-green-500', bg: 'bg-green-50 dark:bg-green-950/30' },
+  blue: { dot: 'bg-blue-500', bg: 'bg-blue-50 dark:bg-blue-950/30' },
+  purple: { dot: 'bg-purple-500', bg: 'bg-purple-50 dark:bg-purple-950/30' },
+  pink: { dot: 'bg-pink-500', bg: 'bg-pink-50 dark:bg-pink-950/30' },
+  teal: { dot: 'bg-teal-500', bg: 'bg-teal-50 dark:bg-teal-950/30' },
+  cyan: { dot: 'bg-cyan-500', bg: 'bg-cyan-50 dark:bg-cyan-950/30' },
+  indigo: { dot: 'bg-indigo-500', bg: 'bg-indigo-50 dark:bg-indigo-950/30' },
+  amber: { dot: 'bg-amber-500', bg: 'bg-amber-50 dark:bg-amber-950/30' },
+  lime: { dot: 'bg-lime-500', bg: 'bg-lime-50 dark:bg-lime-950/30' },
+  gray: { dot: 'bg-gray-500', bg: 'bg-gray-50 dark:bg-gray-950/30' },
+} as const;
+
+export const DEFAULT_KEYWORDS: KeywordDefinition[] = [
+  { id: 'red', label: 'Red', color: 'red' },
+  { id: 'orange', label: 'Orange', color: 'orange' },
+  { id: 'yellow', label: 'Yellow', color: 'yellow' },
+  { id: 'green', label: 'Green', color: 'green' },
+  { id: 'blue', label: 'Blue', color: 'blue' },
+  { id: 'purple', label: 'Purple', color: 'purple' },
+  { id: 'pink', label: 'Pink', color: 'pink' },
+];
+
 interface SettingsState {
   // Appearance
   fontSize: FontSize;
@@ -64,6 +97,9 @@ interface SettingsState {
   // Folders
   folderIcons: Record<string, string>; // mailboxId -> icon name
 
+  // Keywords (labels/tags)
+  emailKeywords: KeywordDefinition[];
+
   // Advanced
   debugMode: boolean;
   settingsSyncDisabled: boolean;
@@ -86,6 +122,13 @@ interface SettingsState {
   removeTrustedSender: (email: string) => void;
   isSenderTrusted: (email: string) => boolean;
 
+  // Keywords
+  addKeyword: (keyword: KeywordDefinition) => void;
+  updateKeyword: (id: string, updates: Partial<Omit<KeywordDefinition, 'id'>>) => void;
+  removeKeyword: (id: string) => void;
+  reorderKeywords: (keywords: KeywordDefinition[]) => void;
+  getKeywordById: (id: string) => KeywordDefinition | undefined;
+
   // Settings sync
   enableSync: (username: string, serverUrl: string) => void;
   disableSync: () => void;
@@ -129,6 +172,9 @@ const DEFAULT_SETTINGS = {
   // Folders
   folderIcons: {} as Record<string, string>,
 
+  // Keywords
+  emailKeywords: DEFAULT_KEYWORDS,
+
   // Advanced
   debugMode: false,
   settingsSyncDisabled: false,
@@ -188,6 +234,7 @@ export const useSettingsStore = create<SettingsState>()(
           calendarNotificationSound: state.calendarNotificationSound,
           senderFavicons: state.senderFavicons,
           folderIcons: state.folderIcons,
+          emailKeywords: state.emailKeywords,
           debugMode: state.debugMode,
           settingsSyncDisabled: state.settingsSyncDisabled,
           // Cross-store settings
@@ -264,6 +311,33 @@ export const useSettingsStore = create<SettingsState>()(
         return get().trustedSenders.includes(normalizedEmail);
       },
 
+      // Keyword methods
+      addKeyword: (keyword: KeywordDefinition) => {
+        const current = get().emailKeywords;
+        if (current.some(k => k.id === keyword.id)) return;
+        set({ emailKeywords: [...current, keyword] });
+      },
+
+      updateKeyword: (id: string, updates: Partial<Omit<KeywordDefinition, 'id'>>) => {
+        set({
+          emailKeywords: get().emailKeywords.map(k =>
+            k.id === id ? { ...k, ...updates } : k
+          ),
+        });
+      },
+
+      removeKeyword: (id: string) => {
+        set({ emailKeywords: get().emailKeywords.filter(k => k.id !== id) });
+      },
+
+      reorderKeywords: (keywords: KeywordDefinition[]) => {
+        set({ emailKeywords: keywords });
+      },
+
+      getKeywordById: (id: string) => {
+        return get().emailKeywords.find(k => k.id === id);
+      },
+
       // Settings sync methods
       enableSync: (username: string, serverUrl: string) => {
         syncUsername = username;

tailwind.config.ts

@@ -6,6 +6,7 @@ export default {
     "./pages/**/*.{js,ts,jsx,tsx,mdx}",
     "./components/**/*.{js,ts,jsx,tsx,mdx}",
     "./app/**/*.{js,ts,jsx,tsx,mdx}",
+    "./stores/**/*.{js,ts,jsx,tsx}",
   ],
   theme: {
     extend: {