diff --git a/javascript/chronometer.js b/javascript/chronometer.js
index 7a13496..47da365 100644
--- a/javascript/chronometer.js
+++ b/javascript/chronometer.js
@@ -1,34 +1,59 @@
 class Chronometer {
   constructor() {
-    // ... your code goes here
+    this.currentTime = 0; 
+    this.intervalId = null;
+    this.milliseconds = 0;
   }
 
   start(callback) {
-    // ... your code goes here
+    this.intervalId = setInterval(() => {
+      this.milliseconds++;
+      if (this.milliseconds === 1000) {
+        this.currentTime++;
+        this.milliseconds = 0;
+      }
+      if (callback) {
+        callback();
+      }
+    }, 1); 
   }
 
   getMinutes() {
-    // ... your code goes here
+    return Math.floor(this.currentTime / 60);
   }
 
   getSeconds() {
-    // ... your code goes here
+    return Math.floor((this.currentTime % 60) + (this.milliseconds / 1000));
   }
 
+  getMilliseconds() {
+    
+    return this.milliseconds ;
+ }
+
+
   computeTwoDigitNumber(value) {
-    // ... your code goes here
+    if (value < 10) {
+      return `0${value}`;
+    } else {
+      return `${value}`;
+    }
   }
 
   stop() {
-    // ... your code goes here
+    clearInterval(this.intervalId);
   }
 
   reset() {
-    // ... your code goes here
+    this.currentTime = 0;
+    this.milliseconds = 0;
   }
 
   split() {
-    // ... your code goes here
+    const minutes = this.computeTwoDigitNumber(this.getMinutes());
+    const seconds = this.computeTwoDigitNumber(this.getSeconds());
+    const milliseconds = this.computeTwoDigitNumber(this.getMilliseconds());
+    return `${minutes}:${seconds}.${milliseconds}`;
   }
 }
 
diff --git a/javascript/index.js b/javascript/index.js
index fb3a43a..751caa0 100644
--- a/javascript/index.js
+++ b/javascript/index.js
@@ -13,53 +13,100 @@ const milDecElement = document.getElementById('milDec');
 const milUniElement = document.getElementById('milUni');
 const splitsElement = document.getElementById('splits');
 
+function computeTwoDigitNumber(number) {
+  return number.toString().padStart(2, '0');
+}
 function printTime() {
-  // ... your code goes here
+  printMinutes();
+  printSeconds();
+  printMilliseconds();
 }
 
 function printMinutes() {
-  // ... your code goes here
+  const minutes = chronometer.getMinutes();
+  minDecElement.innerText = computeTwoDigitNumber(minutes)[0];
+  minUniElement.innerText = computeTwoDigitNumber(minutes)[1];
 }
 
 function printSeconds() {
-  // ... your code goes here
+  const seconds = chronometer.getSeconds();
+  secDecElement.innerText = computeTwoDigitNumber(seconds)[0];
+  secUniElement.innerText = computeTwoDigitNumber(seconds)[1];
+
 }
 
 // ==> BONUS
 function printMilliseconds() {
-  // ... your code goes here
+  const milliseconds = chronometer.getMilliseconds();
+  milDecElement.innerText = computeTwoDigitNumber(milliseconds)[0];
+  milUniElement.innerText = computeTwoDigitNumber(milliseconds)[1];
+
 }
 
 function printSplit() {
-  // ... your code goes here
+  const newSplit = document.createElement('li');
+  newSplit.className = 'list-item';
+  newSplit.innerHTML = chronometer.split(); // Get formatted split time
+  splitsElement.appendChild(newSplit);
 }
 
 function clearSplits() {
-  // ... your code goes here
+  splitsElement.innerHTML = ''; 
 }
 
 function setStopBtn() {
-  // ... your code goes here
+  btnLeftElement.innerText = 'STOP';
+  btnLeftElement.className = 'btn stop';
+  btnRightElement.innerText = 'SPLIT';
+  btnRightElement.className = 'btn split';
+  chronometer.start(printTime);
 }
 
 function setSplitBtn() {
-  // ... your code goes here
+
+  chronometer.split();
+  
 }
 
 function setStartBtn() {
-  // ... your code goes here
+  btnLeftElement.innerText = 'START';
+  btnLeftElement.className = 'btn start';
+  btnRightElement.innerText = 'RESET';
+  btnRightElement.className = 'btn reset';
+  chronometer.stop();
 }
 
 function setResetBtn() {
-  // ... your code goes here
+  minDecElement.innerText = '0';
+  minUniElement.innerText = '0';
+  secDecElement.innerText = '0';
+  secUniElement.innerText = '0';
+  milDecElement.innerText = '0';
+  milUniElement.innerText = '0';
+  chronometer.reset();
 }
 
 // Start/Stop Button
 btnLeftElement.addEventListener('click', () => {
-  // ... your code goes here
+  if (btnLeftElement.classList.contains('start')) {
+    
+    setStopBtn();
+    
+  } else {
+   
+    setStartBtn();
+    
+  }
 });
 
 // Reset/Split Button
 btnRightElement.addEventListener('click', () => {
-  // ... your code goes here
+  if (btnRightElement.classList.contains('split')) {
+    printSplit();
+    setSplitBtn();
+  } else {
+    clearSplits();
+   
+   setResetBtn();
+  }
 });