add shadcn compatibility layer and separate brand from accent colors (#39)

Split the semantic "accent" color into two concepts: brand (user-customizable
accent color) and accent (shadcn's neutral hover state). This enables using
shadcn/ui components with minimal modification while preserving the existing
theming system.

ui/goose2/src/features/chat/ui/ChatInput.tsx

@@ -202,7 +202,7 @@ export function ChatInput({
 
             {mentionPersonaId && (
               <div className="mb-2 flex items-center gap-1.5">
-                <span className="inline-flex items-center gap-1 rounded-full bg-accent/10 px-2.5 py-0.5 text-[11px] font-medium text-accent">
+                <span className="inline-flex items-center gap-1 rounded-full bg-brand/10 px-2.5 py-0.5 text-[11px] font-medium text-brand">
                   @
                   {personas.find((p) => p.id === mentionPersonaId)?.displayName}
                   <button

ui/goose2/src/features/chat/ui/MarkdownContent.tsx

@@ -140,7 +140,7 @@ export const MarkdownContent = memo(function MarkdownContent({
         prose-pre:p-0 prose-pre:m-0 !p-0
         prose-code:before:content-none prose-code:after:content-none
         prose-code:break-all prose-code:whitespace-pre-wrap prose-code:font-mono
-        prose-a:break-all prose-a:text-accent prose-a:underline
+        prose-a:break-all prose-a:text-brand prose-a:underline
         prose-table:table prose-table:w-full
         prose-blockquote:text-inherit prose-blockquote:border-border
         prose-td:border prose-td:border-border prose-td:p-2

ui/goose2/src/features/chat/ui/MentionAutocomplete.tsx

@@ -114,7 +114,7 @@ function MentionAvatar({ persona }: { persona: Persona }) {
         "flex h-7 w-7 items-center justify-center rounded-full",
         persona.isBuiltin
           ? "bg-foreground/10 text-foreground"
-          : "bg-accent/10 text-accent",
+          : "bg-brand/10 text-brand",
       )}
     >
       {persona.isBuiltin ? (

ui/goose2/src/features/chat/ui/PersonaPicker.tsx

@@ -171,7 +171,7 @@ function PersonaAvatar({
         "flex items-center justify-center rounded-full",
         isBuiltin
           ? "bg-foreground/10 text-foreground"
-          : "bg-accent/10 text-accent",
+          : "bg-brand/10 text-brand",
       )}
     >
       {isBuiltin ? (

ui/goose2/src/features/home/ui/HomeScreen.tsx

@@ -158,7 +158,7 @@ function HomeInput({
 
         {mentionPersonaId && (
           <div className="mb-2 flex items-center gap-1.5">
-            <span className="inline-flex items-center gap-1 rounded-full bg-accent/10 px-2.5 py-0.5 text-[11px] font-medium text-accent">
+            <span className="inline-flex items-center gap-1 rounded-full bg-brand/10 px-2.5 py-0.5 text-[11px] font-medium text-brand">
               @{personas.find((p) => p.id === mentionPersonaId)?.displayName}
               <button
                 type="button"

ui/goose2/src/features/projects/ui/CreateProjectDialog.tsx

@@ -316,7 +316,7 @@ export function CreateProjectDialog({
               type="checkbox"
               checked={useWorktrees}
               onChange={(e) => setUseWorktrees(e.target.checked)}
-              className="h-4 w-4 rounded border-border accent-foreground"
+              className="h-4 w-4 rounded border-border accent-brand"
             />
             <span className="text-xs font-medium text-foreground-secondary">
               Use git worktrees for branch isolation

ui/goose2/src/shared/styles/globals.css

@@ -97,9 +97,30 @@
     --radius-xl: 16px;
     --radius-full: 9999px;
 
-    --color-accent: #3b82f6;
-    --color-accent-foreground: #ffffff;
+    --color-accent: #f5f5f5;
+    --color-accent-foreground: #0a0a0a;
+    --color-brand: #3b82f6;
+    --color-brand-foreground: #ffffff;
     --density-spacing: 1;
+
+    /* shadcn compatibility layer */
+    --background: var(--color-background-primary);
+    --foreground: var(--color-text-primary);
+    --card: var(--color-background-primary);
+    --card-foreground: var(--color-text-primary);
+    --popover: var(--color-background-primary);
+    --popover-foreground: var(--color-text-primary);
+    --primary: var(--color-background-inverse);
+    --primary-foreground: var(--color-text-inverse);
+    --secondary: var(--color-background-secondary);
+    --secondary-foreground: var(--color-text-primary);
+    --muted: var(--color-background-secondary);
+    --muted-foreground: var(--color-text-secondary);
+    --destructive: var(--color-background-danger);
+    --destructive-foreground: var(--color-text-inverse);
+    --border: var(--color-border-primary);
+    --input: var(--color-border-primary);
+    --ring: var(--color-ring-primary);
   }
 
   .dark {
@@ -156,9 +177,30 @@
     --shadow-lg:
       0 10px 15px -3px rgba(0, 0, 0, 0.4), 0 4px 6px -4px rgba(0, 0, 0, 0.3);
 
-    --color-accent: #3b82f6;
-    --color-accent-foreground: #ffffff;
+    --color-accent: #262626;
+    --color-accent-foreground: #fafafa;
+    --color-brand: #3b82f6;
+    --color-brand-foreground: #ffffff;
     --density-spacing: 1;
+
+    /* shadcn compatibility layer */
+    --background: var(--color-background-primary);
+    --foreground: var(--color-text-primary);
+    --card: var(--color-background-secondary);
+    --card-foreground: var(--color-text-primary);
+    --popover: var(--color-background-secondary);
+    --popover-foreground: var(--color-text-primary);
+    --primary: var(--color-background-inverse);
+    --primary-foreground: var(--color-text-inverse);
+    --secondary: var(--color-background-tertiary);
+    --secondary-foreground: var(--color-text-primary);
+    --muted: var(--color-background-tertiary);
+    --muted-foreground: var(--color-text-secondary);
+    --destructive: var(--color-background-danger);
+    --destructive-foreground: var(--color-text-inverse);
+    --border: var(--color-border-primary);
+    --input: var(--color-border-secondary);
+    --ring: var(--color-ring-primary);
   }
 }
 

ui/goose2/src/shared/theme/ThemeProvider.tsx

@@ -32,6 +32,15 @@ function resolveTheme(preference: ThemePreference): ResolvedTheme {
   return preference;
 }
 
+function getContrastColor(hexColor: string): string {
+  const hex = hexColor.replace("#", "");
+  const r = Number.parseInt(hex.slice(0, 2), 16);
+  const g = Number.parseInt(hex.slice(2, 4), 16);
+  const b = Number.parseInt(hex.slice(4, 6), 16);
+  const luminance = (0.299 * r + 0.587 * g + 0.114 * b) / 255;
+  return luminance > 0.5 ? "#000000" : "#ffffff";
+}
+
 export function ThemeProvider({
   children,
   defaultTheme = "system",
@@ -96,8 +105,11 @@ export function ThemeProvider({
 
   React.useEffect(() => {
     const root = window.document.documentElement;
-    root.style.setProperty("--color-accent", accentColor);
-    root.style.setProperty("--color-accent-foreground", "#ffffff");
+    root.style.setProperty("--color-brand", accentColor);
+    root.style.setProperty(
+      "--color-brand-foreground",
+      getContrastColor(accentColor),
+    );
 
     const spacingScale: Record<Density, string> = {
       compact: "0.75",

ui/goose2/src/shared/ui/SearchBar.tsx

@@ -20,7 +20,7 @@ export function SearchBar({
 }: SearchBarProps) {
   return (
     <div className={cn("relative", className)}>
-      <Search className="absolute left-3 top-1/2 -translate-y-1/2 w-4 h-4 text-foreground-secondary/60" />
+      <Search className="absolute left-3 top-1/2 h-4 w-4 -translate-y-1/2 text-muted-foreground" />
       <input
         type="search"
         autoComplete="off"
@@ -28,7 +28,7 @@ export function SearchBar({
         value={value}
         onChange={(e) => onChange(e.target.value)}
         placeholder={placeholder}
-        className="w-full pl-9 pr-3 py-2 text-sm bg-background-secondary border border-border-secondary/50 rounded-lg placeholder:text-foreground-secondary/40 focus:outline-none focus:ring-1 focus:ring-ring focus:border-border-primary transition-colors"
+        className="w-full rounded-lg border border-input bg-secondary py-2 pr-3 pl-9 text-sm placeholder:text-muted-foreground transition-colors focus:outline-none focus:ring-1 focus:ring-ring"
       />
     </div>
   );

ui/goose2/src/shared/ui/button.tsx

@@ -5,20 +5,20 @@ import { cva, type VariantProps } from "class-variance-authority";
 import { cn } from "@/shared/lib/cn";
 
 const buttonVariants = cva(
-  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md text-sm font-medium transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring disabled:pointer-events-none disabled:opacity-50 [&_svg]:pointer-events-none [&_svg]:size-4 [&_svg]:shrink-0",
+  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md text-sm font-medium transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring/50 disabled:pointer-events-none disabled:opacity-50 [&_svg]:pointer-events-none [&_svg]:size-4 [&_svg]:shrink-0",
   {
     variants: {
       variant: {
         default:
-          "bg-background-inverse text-foreground-inverse shadow hover:bg-background-inverse/90",
+          "bg-primary text-primary-foreground shadow-sm hover:bg-primary/90",
         destructive:
-          "bg-background-danger text-foreground-inverse shadow-sm hover:bg-background-danger/90",
+          "bg-destructive text-destructive-foreground shadow-sm hover:bg-destructive/90",
         outline:
-          "border border-border bg-background shadow-sm hover:bg-background-secondary hover:text-foreground",
+          "border border-input bg-background shadow-sm hover:bg-accent hover:text-accent-foreground",
         secondary:
-          "bg-background-secondary text-foreground shadow-sm hover:bg-background-secondary/80",
-        ghost: "hover:bg-background-secondary hover:text-foreground",
-        link: "text-foreground underline-offset-4 hover:underline",
+          "bg-secondary text-secondary-foreground shadow-sm hover:bg-secondary/80",
+        ghost: "hover:bg-accent hover:text-accent-foreground",
+        link: "text-brand underline-offset-4 hover:underline",
       },
       size: {
         default: "h-9 px-4 py-2",

ui/goose2/src/shared/ui/dropdown-menu.tsx

@@ -18,7 +18,7 @@ const DropdownMenuContent = React.forwardRef<
       ref={ref}
       sideOffset={sideOffset}
       className={cn(
-        "z-50 min-w-[8rem] overflow-hidden rounded-md border border-border bg-background p-1 shadow-md",
+        "z-50 min-w-[8rem] overflow-hidden rounded-md border bg-popover p-1 text-popover-foreground shadow-md",
         "data-[state=open]:animate-in data-[state=closed]:animate-out",
         "data-[state=closed]:fade-out-0 data-[state=open]:fade-in-0",
         "data-[state=closed]:zoom-out-95 data-[state=open]:zoom-in-95",
@@ -42,7 +42,7 @@ const DropdownMenuItem = React.forwardRef<
     ref={ref}
     className={cn(
       "relative flex cursor-default select-none items-center rounded-sm px-2 py-1.5 text-sm outline-none transition-colors",
-      "focus:bg-background-secondary focus:text-foreground",
+      "focus:bg-accent focus:text-accent-foreground",
       "data-[disabled]:pointer-events-none data-[disabled]:opacity-50",
       inset && "pl-8",
       className,
@@ -61,7 +61,7 @@ const DropdownMenuLabel = React.forwardRef<
   <DropdownMenuPrimitive.Label
     ref={ref}
     className={cn(
-      "px-2 py-1.5 text-xs font-semibold text-foreground-secondary",
+      "px-2 py-1.5 text-xs font-semibold text-muted-foreground",
       inset && "pl-8",
       className,
     )}

ui/goose2/src/shared/ui/popover.tsx

@@ -16,7 +16,7 @@ const PopoverContent = React.forwardRef<
       align={align}
       sideOffset={sideOffset}
       className={cn(
-        "z-50 w-72 rounded-md border border-border bg-background p-4 shadow-md outline-none",
+        "z-50 w-72 rounded-md border bg-popover p-4 text-popover-foreground shadow-md outline-none",
         "data-[state=open]:animate-in data-[state=closed]:animate-out",
         "data-[state=closed]:fade-out-0 data-[state=open]:fade-in-0",
         "data-[state=closed]:zoom-out-95 data-[state=open]:zoom-in-95",

ui/goose2/src/shared/ui/tooltip.tsx

@@ -15,7 +15,7 @@ const TooltipContent = React.forwardRef<
       ref={ref}
       sideOffset={sideOffset}
       className={cn(
-        "z-50 overflow-hidden rounded-md bg-foreground px-3 py-1.5 text-xs text-background",
+        "z-50 overflow-hidden rounded-md bg-primary px-3 py-1.5 text-xs text-primary-foreground shadow-md",
         "animate-in fade-in-0 zoom-in-95",
         "data-[state=closed]:animate-out data-[state=closed]:fade-out-0 data-[state=closed]:zoom-out-95",
         "data-[side=bottom]:slide-in-from-top-2 data-[side=left]:slide-in-from-right-2",

ui/goose2/tailwind.config.js

@@ -26,6 +26,27 @@ export default {
         lg: "var(--shadow-lg)",
       },
       colors: {
+        card: "var(--card)",
+        "card-foreground": "var(--card-foreground)",
+        popover: "var(--popover)",
+        "popover-foreground": "var(--popover-foreground)",
+        primary: {
+          DEFAULT: "var(--primary)",
+          foreground: "var(--primary-foreground)",
+        },
+        secondary: {
+          DEFAULT: "var(--secondary)",
+          foreground: "var(--secondary-foreground)",
+        },
+        muted: {
+          DEFAULT: "var(--muted)",
+          foreground: "var(--muted-foreground)",
+        },
+        destructive: {
+          DEFAULT: "var(--destructive)",
+          foreground: "var(--destructive-foreground)",
+        },
+        input: "var(--input)",
         background: {
           DEFAULT: "var(--color-background-primary)",
           primary: "var(--color-background-primary)",
@@ -79,6 +100,10 @@ export default {
           DEFAULT: "var(--color-accent)",
           foreground: "var(--color-accent-foreground)",
         },
+        brand: {
+          DEFAULT: "var(--color-brand)",
+          foreground: "var(--color-brand-foreground)",
+        },
         // Semantic status colors for inline use (status dots, badges)
         green: { 500: "#91cb80" },
         red: { 500: "#f94b4b" },