body {
  font-family: 'Arial', sans-serif;
  margin: 0;
  padding: 0;
  background-color: #f4f7f6;
  color: #333;
  line-height: 1.6;
}

header {
  background-color: #2c3e50;
  color: white;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

header .logo {
  font-size: 1.8rem;
  font-weight: bold;
  font-family: 'Noto Sans JP', sans-serif;
}


nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
}

nav ul li {
  margin-left: 20px;
}

nav ul li a {
  color: white;
  text-decoration: none;
  font-weight: bold;
  padding: 0.5rem 1rem;
  border-radius: 5px;
  transition: background-color 0.3s ease;
}

nav ul li a:hover {
  background-color: #34495e;
}

main {
  display: flex;
  flex-direction: column;
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 20px;
}

.hero {
  text-align: center;
  background-color: #e0f2f7;
  padding: 4rem 2rem;
  border-radius: 10px;
  margin-bottom: 2rem;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.hero h1 {
  color: #007bff;
  font-size: 2.8rem;
  margin-bottom: 0.5rem;
}

.hero p {
  font-size: 1.2rem;
  color: #555;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

article {
  background-color: white;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  transition: transform 0.3s ease;
}

article:hover {
  transform: translateY(-5px);
}

article h2 {
  color: #3498db;
  margin-top: 0;
}

article h2 a {
  text-decoration: none;
  color: #3498db;
}

article h2 a:hover {
  text-decoration: underline;
}

.meta {
  font-size: 0.9rem;
  color: #888;
  margin-bottom: 0.8rem;
}

.single-article h1 {
  font-size: 2.2rem;
  color: #2c3e50;
}

.single-article h2 {
  margin-top: 2rem;
  color: #007bff;
}

aside {
  background-color: #dbe4f1;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  margin-bottom: 2rem;
}

aside h3 {
  color: #2980b9;
  margin-top: 0;
  border-bottom: 2px solid #2980b9;
  padding-bottom: 5px;
  margin-bottom: 1rem;
}

aside ul {
  list-style: none;
  padding: 0;
}

aside ul li {
  margin-bottom: 8px;
  color: #555;
}

aside ul li a {
  color: #333;
  text-decoration: none;
}

aside ul li a:hover {
  text-decoration: underline;
}

footer {
  background-color: #2c3e50;
  color: white;
  text-align: center;
  padding: 1.5rem;
  margin-top: 2rem;
}

@media (min-width: 768px) {
  main {
    flex-direction: row;
    gap: 2rem;
  }
  .content {
    flex: 1;
  }
  aside {
    width: 280px;
    flex-shrink: 0;
  }
}