* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  background-color: #f0f4f8;
  color: #333;
  padding: 0;
}

header {
  background-color: #2a9d8f;
  color: white;
  text-align: center;
  padding: 40px 20px;
}

header h1 {
  font-size: 2.5rem;
  margin-bottom: 10px;
}

header p {
  font-size: 1.2rem;
}

nav {
  background-color: #264653;
}

nav ul {
  list-style: none;
  display: flex;
  justify-content: center;
  padding: 10px 0;
}

nav li {
  margin: 0 15px;
}

nav a {
  color: white;
  text-decoration: none;
  font-weight: bold;
  padding: 10px 15px;
  transition: background 0.3s;
}

nav a:hover {
  background-color: #1e3a3a;
  border-radius: 5px;
}

main {
  padding: 30px 20px;
  max-width: 900px;
  margin: auto;
  background-color: #fff;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

section {
  margin-bottom: 30px;
}

section h2 {
  color: #2a9d8f;
  margin-bottom: 10px;
}

section p {
  font-size: 1rem;
}

img {
  max-width: 100%;
  height: auto;
  margin-top: 15px;
}

article h3 {
  color: #264653;
  margin-top: 20px;
  margin-bottom: 10px;
}

aside {
  background-color: #e9f5f2;
  padding: 15px;
  margin-top: 30px;
  border-left: 5px solid #2a9d8f;
}

aside h4 {
  margin-bottom: 10px;
}

footer {
  background-color: #2a9d8f;
  color: white;
  text-align: center;
  padding: 20px 10px;
  margin-top: 40px;
  font-size: 0.9rem;
}