.nav-menu {
  background-color: #2c3e50;
  padding: 0;
  margin: 0;
  list-style: none;
  display: flex;
  border-radius: 8px;
  overflow: hidden;
}

.nav-menu li {
  flex: 1;
}

.nav-menu a {
  display: block;
  padding: 15px 20px;
  color: white;
  text-decoration: none;
  text-align: center;
  transition-duration: 0.3s;
  transition-property: background-color, color;
}

.nav-menu a:hover {
  background-color: #3498db;
  color: #fff;
}