Add the Gruvbox theme.

source/scss/style.scss

@@ -4,6 +4,7 @@
 // Theme definitions
 @use 'themes/default';
 @use 'themes/dracula';
+@use 'themes/gruvbox';
 @use 'themes/high-contrast';
 @use 'themes/love';
 @use 'themes/monokai';

source/scss/themes/_gruvbox.scss

@@ -0,0 +1,13 @@
+.gruvbox-dark {
+  --foreground-1: #fbf1c7;
+  --foreground-2: #ebdbb2;
+  --background-1: #282828;
+  --background-2: #3c3836;
+}
+
+.gruvbox-light {
+  --foreground-1: #282828;
+  --foreground-2: #3c3836;
+  --background-1: #fbf1c7;
+  --background-2: #ebdbb2;
+}

source/ts/utilities/themes.ts

@@ -40,6 +40,14 @@ export const themes: Theme[] = [
     cssClass: 'high-contrast-white',
     name: 'High Contrast White',
   },
+  {
+    cssClass: 'gruvbox-dark',
+    name: 'Gruvbox Dark',
+  },
+  {
+    cssClass: 'gruvbox-light',
+    name: 'Gruvbox Light',
+  },
 ].sort((a, b) => a.name.localeCompare(b.name));
 
 export const themeContext = createContext<Theme>(defaultTheme);