Calling a list of colors within a switch case for neopixel

Projects Programming
6

Here is the entire code. I defined the colors in the setup but they still show as undeclared in the other loops.

#include <Adafruit_LiquidCrystal.h>
#include <Adafruit_NeoPixel.h>
#define PIN 13
#define leds 24

Adafruit_NeoPixel strip = Adafruit_NeoPixel(leds, PIN, NEO_GRB + NEO_KHZ800);
Adafruit_LiquidCrystal lcd_0(0);

int   pb_pin = 3;
int   state = 1;
bool  pb;
bool  pressed = false;
int   pot_pin = A1;
int   pot;

void setup() 
{
  pinMode(pb_pin, INPUT_PULLUP);
  strip.begin();
  Serial.begin(9600);
  lcd_0.begin(20,4);
  strip.clear();

  uint32_t red    = strip.Color(255, 0, 0);             //Define the color red
  uint32_t green  = strip.Color(0, 255, 0);           //Define the color green
  uint32_t blue   = strip.Color(0, 0, 255);            //Define the color blue
  uint32_t white  = strip.Color(255, 255, 255);       //Define the color white
}

void loop() 
{
  pb = digitalRead(pb_pin);
  pot = analogRead(pot_pin);

  pot = map(pot, 0, 1023, 255, 0);

  if(pb == pressed){
    state = state + 1;
    Serial.println(state);
    while(digitalRead(pb_pin) == pressed){delay(100);}
  }
  switch (state){
    case 1:
      FX1();
      Serial.print("pot: ");
      Serial.println(pot);
      strip.setBrightness(pot);
      break;
    case 2:
      FX2();
      strip.setBrightness(pot);
      break;
    case 3:
      FX3();
      strip.setBrightness(pot);
      break;
    default:
      strip.clear();
      strip.show();
      state = 0;
      break;
  }
}

void FX1(){
  strip.clear();
  strip.fill(red, 0, leds/3);
  strip.fill(white, leds/3, leds/3);
  strip.fill(blue, (leds/3)*2, leds/3);
  strip.show();
}

void FX2(){
  strip.clear();
  strip.fill(green, 0, leds/4);
  strip.fill(white, leds/4, leds/4);
  strip.fill(green, (leds/4)*2, leds/4);
  strip.fill(white, (leds/4)*3, leds/4);
  strip.show();
}

void FX3(){
  strip.clear();
  strip.rainbow(0,1,255,255,true);
  strip.show();
}