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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
    Ubuntu, Cantarell, sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #f4f4f4;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 20px;
}

.navbar {
  background-color: #1a472a;
  color: white;
  padding: 1rem 0;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.5rem;
  font-weight: bold;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-menu a {
  color: white;
  text-decoration: none;
  transition: color 0.3s;
}

.nav-menu a:hover,
.nav-menu a.active {
  color: #4caf50;
}

.signin-btn {
  background-color: #4caf50;
  padding: 0.5rem 1.5rem;
  border-radius: 5px;
  font-weight: 500;
}

.signin-btn:hover {
  background-color: #45a049;
  color: white !important;
}

main {
  background-color: white;
  margin: 2rem auto;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.hero {
  text-align: center;
  padding: 2rem 0;
  margin-bottom: 2rem;
  border-bottom: 2px solid #4caf50;
}

.hero h2 {
  font-size: 2rem;
  color: #1a472a;
  margin-bottom: 1rem;
}

.hero p {
  font-size: 1.1rem;
  color: #666;
}

main h2 {
  margin-bottom: 2rem;
  color: #1a472a;
  border-bottom: 3px solid #4caf50;
  padding-bottom: 0.5rem;
}

.post {
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid #eee;
}

.post:last-child {
  border-bottom: none;
}

.post h3 {
  margin-bottom: 0.5rem;
}

.post h3 a {
  color: #1a472a;
  text-decoration: none;
  transition: color 0.3s;
}

.post h3 a:hover {
  color: #4caf50;
}

.meta {
  color: #7f8c8d;
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.post p {
  margin-bottom: 1rem;
}

.read-more {
  color: #4caf50;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

.read-more:hover {
  color: #45a049;
}

.article-content {
  line-height: 1.8;
}

.article-content h3 {
  margin-top: 1.5rem;
  margin-bottom: 1rem;
  color: #1a472a;
}

.article-content p {
  margin-bottom: 1rem;
}

.back-link {
  display: inline-block;
  margin-top: 2rem;
  color: #4caf50;
  text-decoration: none;
  font-weight: 500;
}

.back-link:hover {
  color: #45a049;
}

.course-info {
  background-color: #f0f8f0;
  padding: 1.5rem;
  border-radius: 8px;
  margin: 1.5rem 0;
}

.course-info h3 {
  color: #1a472a;
  margin-top: 0;
}

footer {
  background-color: #1a472a;
  color: white;
  text-align: center;
  padding: 1.5rem 0;
  margin-top: 3rem;
}

@media (max-width: 768px) {
  .navbar .container {
    flex-direction: column;
    gap: 1rem;
  }

  .nav-menu {
    gap: 1rem;
  }
}