Grove i2c LCD with random backlight colour

rando_backlight.ino

// libraries for i2c and the specific display
#include <Wire.h>
#include "rgb_lcd.h"

rgb_lcd lcd;

void setup() {

    // make sure the random is random
    randomSeed(analogRead(0));
    
    // set up the LCD's number of columns and rows:
    lcd.begin(16, 2);
    
    // Print our message to the LCD.
    lcd.print("hello, world!");
}

void loop() {
  
    // Turn off the display:
    lcd.noDisplay();
    delay(500);
  
    // Turn on the display:
    lcd.display();

    // Random colours
    int colorR = random(255);
    int colorG = random(255);
    int colorB = random(255);

    lcd.setRGB(colorR, colorG, colorB);
    delay(500);
}