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

body {
  font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
  background-color: #f8f9fa;
  color: #333;
  line-height: 1.6;
  display: flex;
  flex-direction: column;
  min-height: 100%;
}

a {
  color: #3498db;
  text-decoration: none;
  transition: color 0.3s;
}
a:hover {
  color: rgb(29.2970711297, 110.6778242678, 165.2029288703);
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

.header {
  background-color: #2c3e50;
  padding: 1rem 0;
}
.header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.header .logo a {
  color: #fff;
  font-size: 1.5rem;
  font-weight: bold;
}
.header .nav ul {
  display: flex;
  list-style: none;
  gap: 20px;
}
.header .nav ul a {
  color: #ddd;
}
.header .nav ul a:hover {
  color: #fff;
}

main {
  flex-grow: 1;
}

.hero {
  text-align: center;
  padding: 4rem 0;
  margin-bottom: 2rem;
}
.hero .catchphrase {
  font-size: 2.2rem;
  margin-bottom: 1rem;
}
.hero .intro {
  font-size: 1.1rem;
  color: #666;
  margin-bottom: 1.5rem;
}
.hero .social-links a {
  display: inline-block;
  margin: 0 10px;
  padding: 8px 16px;
  border: 1px solid #3498db;
  border-radius: 4px;
}
.hero .social-links a:hover {
  background-color: #3498db;
  color: #fff;
}

.content-wrapper {
  display: flex;
  gap: 40px;
  margin-bottom: 4rem;
}
@media (max-width: 768px) {
  .content-wrapper {
    flex-direction: column;
  }
}

.articles-area {
  flex: 3;
}

.sidebar {
  flex: 1;
}
.sidebar .widget {
  background: #fff;
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}
.sidebar .widget h3 {
  margin-bottom: 1rem;
  border-bottom: 2px solid #eaeaea;
  padding-bottom: 0.5rem;
  font-size: 1.2rem;
}
.sidebar .tag-cloud {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.sidebar .tag-cloud li a {
  background: #f8f9fa;
  padding: 5px 10px;
  border-radius: 4px;
  font-size: 0.9rem;
  color: #333;
  border: 1px solid #eaeaea;
  display: block;
}
.sidebar .tag-cloud li a:hover {
  background: #3498db;
  color: #fff;
  border-color: #3498db;
}

section {
  margin-bottom: 3rem;
}
section h3 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  border-left: 4px solid #3498db;
  padding-left: 10px;
}

.card {
  background: #fff;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
  margin-bottom: 20px;
  overflow: hidden;
  transition: transform 0.2s, box-shadow 0.2s;
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}
.card .card-content {
  padding: 20px;
}
.card .card-content time {
  font-size: 0.85rem;
  color: #888;
  margin-right: 10px;
}
.card .card-content .tag {
  font-size: 0.75rem;
  background: #f8f9fa;
  padding: 4px 8px;
  border-radius: 4px;
  color: #666;
  border: 1px solid #eaeaea;
}
.card .card-content h4 {
  font-size: 1.3rem;
  margin: 12px 0;
}
.card .card-content h4 a {
  color: #333;
}
.card .card-content h4 a:hover {
  color: #3498db;
}
.card .card-content p {
  font-size: 0.95rem;
  color: #555;
}

.footer {
  background: #2c3e50;
  color: #fff;
  text-align: center;
  padding: 2rem 0;
}
.footer p {
  font-size: 0.9rem;
}