#include <TM1637Display.h>

unsigned long timerDuration = 60;

#define CLK 2
#define DIO 3
TM1637Display display = TM1637Display(CLK, DIO);

void setup() {
  display.clear();
	display.setBrightness(7); // set the brightness to 7 (0:dimmest, 7:brightest)
}

void loop() {
  display.showNumberDec(timerDuration, true);
  delay(1000);
  if (timerDuration > 0) timerDuration --;
}