bool blueLedState = false;
bool redLedState = false;
unsigned long time = 0;
unsigned long lasttime = 0;
int prd = 1000;

void setup() {
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
pinMode(4, INPUT_PULLUP);
}

void loop() {
if (!digitalRead(4)){
  blueLedState = !blueLedState;
  delay(500);
}
digitalWrite(3, blueLedState);

time = millis();
if (time - lasttime >prd){
  redLedState = !redLedState;
  lasttime = time;
} 
digitalWrite(2, HIGH);

}