web/src/lib/theme.ts

const KEY = "chatterbox.theme";

export type Theme = "light" | "dark";

export function getTheme(): Theme {
  const stored = localStorage.getItem(KEY) as Theme | null;
  if (stored === "light" || stored === "dark") return stored;
  return "dark";
}

export function setTheme(t: Theme) {
  localStorage.setItem(KEY, t);
  document.documentElement.classList.toggle("dark", t === "dark");
}

export function applyInitialTheme() {
  setTheme(getTheme());
}