@@ -1,15 +1,51 @@
 let countDown;
+const timerDisplay = document.querySelector('.display__time-left');
+const endTime = document.querySelector('.display__end-time');
+const buttons = document.querySelectorAll('[data-time]');
 function timer(seconds) {
+	clearInterval(countDown);
 	const now = Date.now();
 	const then = now + seconds * 1000;
-	console.log({now, then});
+	dispalyTimeLeft(seconds);
+	displayEndTime(then);
 	countDown = setInterval(() => {
-		const secondsLeft = Math.round((then - now) / 1000);
+		const secondsLeft = Math.round((then - Date.now()) / 1000);
 		//check if stop
 		if(secondsLeft < 0) {
 			clearInterval(countDown);
 			return;
 		}
-		console.log(secondsLeft);
+		dispalyTimeLeft(secondsLeft);
 	}, 1000);
-}
+}
+
+function dispalyTimeLeft(seconds) {
+	const minutes = Math.floor(seconds / 60);
+	const displaySeconds = seconds % 60;
+	const display = `${minutes}:${displaySeconds < 10 ? '0' : ''}${displaySeconds}`;
+	document.title = display;
+	timerDisplay.textContent = display;
+}
+
+function displayEndTime(timestamp){
+	const end = new Date(timestamp);
+	const hour = end.getHours();
+	const minutes = end.getMinutes();
+	endTime.textContent = `Be back at ${hour > 12 ? hour - 12: hour}:${minutes < 10 ? '0':''}${minutes}`;
+}
+
+function startTimer(){
+	const seconds = parseInt(this.dataset.time);
+	timer(seconds);
+}
+
+buttons.forEach(button => {
+	button.addEventListener('click', startTimer);
+})
+
+document.customForm.addEventListener('submit', function(e){
+	e.preventDefault();
+	const minutes = this.minutes.value;
+	timer(minutes * 60);
+	this.reset();
+})