header {
  background-color: #252525;
  padding: 20px 0;
  text-align: center;
  min-height: 200px;
  width: 80%;
  margin: 0 auto;
}

.navbar {
  background-color: #333;
  padding: 15px 0;
  border-bottom: 2px solid #444;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.navbar ul {
  display: flex;
  justify-content: center;
  align-items: center;
  margin: 0;
  padding: 0;
  height: 50px;
  list-style: none;
}

.navbar a {
  font-size: 18px;
  color: white;
  text-decoration: none;
  padding: 0 15px;
}

.navbar li {
  margin: 0 10px;
}

.main-title {
  font-size: 36px;
  font-weight: bold;
  margin-top: 20px;
  margin-bottom: 20px;
  text-align: center;
  color: #fff;
}

.sub-title {
  font-size: 18px;
  color: #666;
  padding-left: 15px;
  padding-right: 15px;
  text-align: center;
}