body {
  margin: 0;
  font-family: Arial, sans-serif;
}

.sidenav {
  height: 100%;
  width: 0;
  position: fixed;
  top: 0;
  left: 0;
}

.sidenav a {
  position: absolute;
  left: 0;
  transition: 0.3s;
  padding: 16px;
  width: 60px;
  text-decoration: none;
  color: white;
  border-radius: 0 5px 5px 0;
  font-size: 20px;
}

.sidenav a:hover {
  width: 200px;
  color: white;
}

/* Individual colors and positions */
.green {
  top: 20px;
  background-color: #4CAF50;
}

.blue {
  top: 80px;
  background-color: #2196F3;
}

.red {
  top: 140px;
  background-color: #f44336;
}

.gray {
  top: 200px;
  background-color: #555;
}

.main {
  margin-left: 70px; /* Leave space for the buttons */
  padding: 16px;
}