diff --git a/web/src/components/ui/card.tsx b/web/src/components/ui/card.tsx
deleted file mode 100644
index 9bd5a25..0000000
--- a/web/src/components/ui/card.tsx
+++ /dev/null
@@ -1,103 +0,0 @@
-import * as React from "react"
-
-import { cn } from "@/lib/utils"
-
-function Card({
-  className,
-  size = "default",
-  ...props
-}: React.ComponentProps<"div"> & { size?: "default" | "sm" }) {
-  return (
-    <div
-      data-slot="card"
-      data-size={size}
-      className={cn(
-        "group/card flex flex-col gap-4 overflow-hidden rounded-xl bg-card py-4 text-sm text-card-foreground ring-1 ring-foreground/10 has-data-[slot=card-footer]:pb-0 has-[>img:first-child]:pt-0 data-[size=sm]:gap-3 data-[size=sm]:py-3 data-[size=sm]:has-data-[slot=card-footer]:pb-0 *:[img:first-child]:rounded-t-xl *:[img:last-child]:rounded-b-xl",
-        className
-      )}
-      {...props}
-    />
-  )
-}
-
-function CardHeader({ className, ...props }: React.ComponentProps<"div">) {
-  return (
-    <div
-      data-slot="card-header"
-      className={cn(
-        "group/card-header @container/card-header grid auto-rows-min items-start gap-1 rounded-t-xl px-4 group-data-[size=sm]/card:px-3 has-data-[slot=card-action]:grid-cols-[1fr_auto] has-data-[slot=card-description]:grid-rows-[auto_auto] [.border-b]:pb-4 group-data-[size=sm]/card:[.border-b]:pb-3",
-        className
-      )}
-      {...props}
-    />
-  )
-}
-
-function CardTitle({ className, ...props }: React.ComponentProps<"div">) {
-  return (
-    <div
-      data-slot="card-title"
-      className={cn(
-        "text-base leading-snug font-medium group-data-[size=sm]/card:text-sm",
-        className
-      )}
-      {...props}
-    />
-  )
-}
-
-function CardDescription({ className, ...props }: React.ComponentProps<"div">) {
-  return (
-    <div
-      data-slot="card-description"
-      className={cn("text-sm text-muted-foreground", className)}
-      {...props}
-    />
-  )
-}
-
-function CardAction({ className, ...props }: React.ComponentProps<"div">) {
-  return (
-    <div
-      data-slot="card-action"
-      className={cn(
-        "col-start-2 row-span-2 row-start-1 self-start justify-self-end",
-        className
-      )}
-      {...props}
-    />
-  )
-}
-
-function CardContent({ className, ...props }: React.ComponentProps<"div">) {
-  return (
-    <div
-      data-slot="card-content"
-      className={cn("px-4 group-data-[size=sm]/card:px-3", className)}
-      {...props}
-    />
-  )
-}
-
-function CardFooter({ className, ...props }: React.ComponentProps<"div">) {
-  return (
-    <div
-      data-slot="card-footer"
-      className={cn(
-        "flex items-center rounded-b-xl border-t bg-muted/50 p-4 group-data-[size=sm]/card:p-3",
-        className
-      )}
-      {...props}
-    />
-  )
-}
-
-export {
-  Card,
-  CardHeader,
-  CardFooter,
-  CardTitle,
-  CardAction,
-  CardDescription,
-  CardContent,
-}
diff --git a/web/src/lib/class-recipes.test.ts b/web/src/lib/class-recipes.test.ts
new file mode 100644
index 0000000..1035923
--- /dev/null
+++ b/web/src/lib/class-recipes.test.ts
@@ -0,0 +1,22 @@
+import { expect, test } from "vitest";
+
+import { rowStateClass, segmentClass } from "./class-recipes";
+
+test("segmentClass active uses the primary tokens + focus ring", () => {
+  const cls = segmentClass(true, "px-2 py-1");
+  expect(cls).toContain("bg-primary");
+  expect(cls).toContain("text-primary-foreground");
+  expect(cls).toContain("focus-visible:ring-ring/50");
+  expect(cls).toContain("px-2");
+});
+
+test("segmentClass inactive uses border, not the primary fill", () => {
+  const cls = segmentClass(false);
+  expect(cls).toContain("border");
+  expect(cls).not.toContain("bg-primary");
+});
+
+test("rowStateClass toggles selected vs idle-hover", () => {
+  expect(rowStateClass(true)).toBe("bg-primary/10");
+  expect(rowStateClass(false)).toBe("hover:bg-muted");
+});
diff --git a/web/src/lib/class-recipes.ts b/web/src/lib/class-recipes.ts
new file mode 100644
index 0000000..06931a6
--- /dev/null
+++ b/web/src/lib/class-recipes.ts
@@ -0,0 +1,14 @@
+import { cn } from "@/lib/utils";
+
+import { focusRing } from "./focus-ring";
+
+/** Segmented-control / filter-pill item. Unifies the active/inactive token recipe +
+ *  focus ring; callers pass their contextual padding/size via `className`. */
+export function segmentClass(active: boolean, className?: string): string {
+  return cn("rounded-md", focusRing, active ? "bg-primary text-primary-foreground" : "border", className);
+}
+
+/** Selected vs idle row background for master-detail / list rows. */
+export function rowStateClass(active: boolean): string {
+  return active ? "bg-primary/10" : "hover:bg-muted";
+}
diff --git a/web/src/lib/use-lang.ts b/web/src/lib/use-lang.ts
new file mode 100644
index 0000000..674cd68
--- /dev/null
+++ b/web/src/lib/use-lang.ts
@@ -0,0 +1,7 @@
+import { useTranslation } from "react-i18next";
+
+/** The instance's active UI language, narrowed to the two supported locales. */
+export function useLang(): "sv" | "en" {
+  const { i18n } = useTranslation();
+  return i18n.language.startsWith("sv") ? "sv" : "en";
+}