adds dark mode

web/src/lib/stores/theme_store.ts

@@ -0,0 +1,14 @@
+import { get, writable, type Writable } from "svelte/store";
+
+type Theme = "dark" | "light"
+
+export const theme: Writable<Theme> = writable("light");
+
+
+export function toggleTheme() {
+    if (get(theme) === "light") {
+        theme.set("dark")
+    } else {
+        theme.set("light");
+    }
+}