diff --git a/config.ts.example b/config.ts.example
index 70caf9c..3b78dde 100644
--- a/config.ts.example
+++ b/config.ts.example
@@ -8,6 +8,12 @@ export class Config {
    */
   static readonly PDS_URL: string = "";
 
+  /**
+   * Theme css file to be used
+   * @default "theme.css"
+   */
+  static readonly THEME: string = "themes/theme.css";
+
   /**
    * The base URL of the frontend service for linking to replies/quotes/accounts etc.
    * @default "https://deer.social" // or https://bsky.app if you're boring
diff --git a/src/app.css b/src/app.css
index 50da734..88cb00c 100644
--- a/src/app.css
+++ b/src/app.css
@@ -1,88 +1,3 @@
-@font-face {
-  font-family: "ProggyClean";
-  src: url(https://witchcraft.systems/ProggyCleanNerdFont-Regular.ttf);
-}
-
-:root {
-  --link-color: #646cff;
-  --link-hover-color: #535bf2;
-  --background-color: #12082b;
-  --header-background-color: #1f1145;
-  --content-background-color: #0d0620;
-  --text-color: white;
-  --border-color: #8054f0;
-  --indicator-inactive-color: #4a4a4a;
-  --indicator-active-color: #8054f0;
-}
-
-::-webkit-scrollbar {
-  width: 0px;
-  background: transparent;
-  padding: 0;
-  margin: 0;
-}
-::-webkit-scrollbar-thumb {
-  background: transparent;
-  border-radius: 0;
-}
-::-webkit-scrollbar-track {
-  background: transparent;
-  border-radius: 0;
-}
-::-webkit-scrollbar-corner {
-  background: transparent;
-  border-radius: 0;
-}
-::-webkit-scrollbar-button {
-  background: transparent;
-  border-radius: 0;
-}
-* {
-  scrollbar-width: none;
-  scrollbar-color: transparent transparent;
-  -ms-overflow-style: none; /* IE and Edge */
-  -webkit-overflow-scrolling: touch;
-  -webkit-scrollbar: none; /* Safari */
-}
-
-a {
-  font-weight: 500;
-  color: var(--link-color);
-  text-decoration: inherit;
-}
-a:hover {
-  color: var(--link-hover-color);
-  text-decoration: underline;
-}
-
 body {
-  margin: 0;
-  display: flex;
-  place-items: center;
-  min-width: 320px;
-  min-height: 100vh;
-  background-color: var(--background-color);
-  font-family: "ProggyClean", monospace;
-  font-size: 24px;
-  color: var(--text-color);
-  border-color: var(--border-color);
-  overflow-wrap: break-word;
-  word-wrap: normal;
-  word-break: break-word;
-  hyphens: none;
-}
-
-h1 {
-  font-size: 3.2em;
-  line-height: 1.1;
-}
-
-#app {
-  max-width: 1400px;
-  width: 100%;
-  margin: 0;
-  padding: 0;
-  margin-left: auto;
-  margin-right: auto;
-  text-align: center;
-}
+  background-color: red;
+}
\ No newline at end of file
diff --git a/src/themes/theme.css b/src/themes/theme.css
new file mode 100644
index 0000000..35739c0
--- /dev/null
+++ b/src/themes/theme.css
@@ -0,0 +1,89 @@
+@font-face {
+  font-family: "ProggyClean";
+  src: url(https://witchcraft.systems/ProggyCleanNerdFont-Regular.ttf);
+}
+
+:root {
+  --link-color: #646cff;
+  --link-hover-color: #535bf2;
+  --background-color: #12082b;
+  --header-background-color: #1f1145;
+  --content-background-color: #0d0620;
+  --text-color: white;
+  --border-color: #8054f0;
+  --indicator-inactive-color: #4a4a4a;
+  --indicator-active-color: #8054f0;
+}
+
+
+::-webkit-scrollbar {
+  width: 0px;
+  background: transparent;
+  padding: 0;
+  margin: 0;
+}
+::-webkit-scrollbar-thumb {
+  background: transparent;
+  border-radius: 0;
+}
+::-webkit-scrollbar-track {
+  background: transparent;
+  border-radius: 0;
+}
+::-webkit-scrollbar-corner {
+  background: transparent;
+  border-radius: 0;
+}
+::-webkit-scrollbar-button {
+  background: transparent;
+  border-radius: 0;
+}
+* {
+  scrollbar-width: none;
+  scrollbar-color: transparent transparent;
+  -ms-overflow-style: none; /* IE and Edge */
+  -webkit-overflow-scrolling: touch;
+  -webkit-scrollbar: none; /* Safari */
+}
+
+a {
+  font-weight: 500;
+  color: var(--link-color);
+  text-decoration: inherit;
+}
+a:hover {
+  color: var(--link-hover-color);
+  text-decoration: underline;
+}
+
+body {
+  margin: 0;
+  display: flex;
+  place-items: center;
+  min-width: 320px;
+  min-height: 100vh;
+  background-color: var(--background-color);
+  font-family: "ProggyClean", monospace;
+  font-size: 24px;
+  color: var(--text-color);
+  border-color: var(--border-color);
+  overflow-wrap: break-word;
+  word-wrap: normal;
+  word-break: break-word;
+  hyphens: none;
+}
+
+h1 {
+  font-size: 3.2em;
+  line-height: 1.1;
+}
+
+#app {
+  max-width: 1400px;
+  width: 100%;
+  margin: 0;
+  padding: 0;
+  margin-left: auto;
+  margin-right: auto;
+  text-align: center;
+}
diff --git a/theming.ts b/theming.ts
new file mode 100644
index 0000000..60117fd
--- /dev/null
+++ b/theming.ts
@@ -0,0 +1,30 @@
+import { Plugin } from 'vite';
+import { Config } from './config';
+// Replaces app.css with the contents of the file specified in the
+// config file.
+
+export const themePlugin = (): Plugin => {
+    const themeFile = Config.THEME;
+    console.log(`Using theme file: ${themeFile}`);
+    return {
+        name: 'theme-generator',
+        transform(code, id) {
+            if (id.endsWith('app.css')) {
+                // Read the theme file and replace the contents of app.css with it
+                // Needs full path to the file
+                const themeCode = Deno.readTextFileSync(Deno.cwd() + '/src/themes/' + themeFile);
+                // Replace the contents of app.css with the theme code
+
+                // and add a comment at the top
+                const themeComment = `/* Generated from ${themeFile} */\n`;
+                const themeCodeWithComment = themeComment + themeCode;
+                // Return the theme code as the new contents of app.css
+                return {
+                    code: themeCodeWithComment,
+                    map: null,
+                };
+            }
+            return null;
+        }
+    };
+};
\ No newline at end of file
diff --git a/vite.config.ts b/vite.config.ts
index 20d2272..96d3c8c 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -1,7 +1,11 @@
 import { defineConfig } from "vite";
 import { svelte } from "@sveltejs/vite-plugin-svelte";
+import { themePlugin } from "./theming";
 
 // https://vite.dev/config/
 export default defineConfig({
-  plugins: [svelte()],
+  plugins: [
+    themePlugin(),
+    svelte(),
+  ],
 });