// Pin Definitions
const int blueLedPin = 16;  // Blue LED connected to GPIO 10 (sourcing mode)
const int redLedPin = 17;   // Red LED connected to GPIO 11 (sinking mode)
const int buttonPin = 18;   // Push button connected to GPIO 12 (active-low)

void setup() {
  // Initialize pins
  pinMode(blueLedPin, OUTPUT);  // Set blue LED pin as output
  pinMode(redLedPin, OUTPUT);   // Set red LED pin as output
  pinMode(buttonPin, INPUT);    // Set button pin as input

  // Initial state: Blue LED ON, Red LED OFF
  digitalWrite(blueLedPin, HIGH);  // Sourcing mode: HIGH turns on the blue LED
  digitalWrite(redLedPin, HIGH);   // Sinking mode: HIGH keeps the red LED off
}

void loop() {
  // Read the state of the button (active-low)
  int buttonState = digitalRead(buttonPin);

  if (buttonState == LOW) {
    // Button is pressed (active-low)
    digitalWrite(blueLedPin, LOW);   // Turn off the blue LED
    digitalWrite(redLedPin, LOW);    // Turn on the red LED (sinking mode)
  } else {
    // Button is not pressed
    digitalWrite(blueLedPin, HIGH);  // Turn on the blue LED
    digitalWrite(redLedPin, HIGH);   // Turn off the red LED
  }
}