Add white and black themes

SettingsPage.tsx

@@ -188,11 +188,12 @@ export default function SettingsPage() {
             dropdownIconColor={color}
             selectedValue={color}
             onValueChange={value => setColor(value)}>
-            {darkColors.concat(lightColors).map(darkColor => (
+            {darkColors.concat(lightColors).map(colorOption => (
               <Picker.Item
-                value={darkColor.hex}
-                label={`${darkColor.name} theme`}
-                color={darkColor.hex}
+                key={colorOption.hex}
+                value={colorOption.hex}
+                label={`${colorOption.name} theme`}
+                color={colorOption.hex}
               />
             ))}
           </Picker>

colors.ts

@@ -1,9 +1,11 @@
 export const lightColors = [
   {hex: '#B3E5FC', name: 'Cyan'},
   {hex: '#FFC0CB', name: 'Pink'},
+  {hex: '#FFFFFF', name: 'White'},
 ];
 
 export const darkColors = [
   {hex: '#8156A7', name: 'Purple'},
   {hex: '#007AFF', name: 'Blue'},
+  {hex: '#000000', name: 'Black'},
 ];