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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.7;
  color: #1a1a1a;
  background: #fafafa;
}

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 20px;
}

header {
  background: #fff;
  border-bottom: 1px solid #eaeaea;
  padding: 18px 0;
  position: sticky;
  top: 0;
  z-index: 10;
}

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

header h1 {
  font-size: 1.3rem;
  font-weight: 600;
}

header h1 a {
  color: #1a1a1a;
  text-decoration: none;
}

nav a {
  margin-left: 24px;
  color: #555;
  text-decoration: none;
  font-size: 0.95rem;
}

nav a:hover {
  color: #000;
}

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 40px 20px 60px;
}

.intro {
  margin-bottom: 40px;
  font-size: 1.05rem;
  color: #444;
  line-height: 1.8;
}

.articles-grid {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.card {
  background: #fff;
  padding: 24px;
  border-radius: 6px;
  border: 1px solid #eaeaea;
}

.card h2 {
  font-size: 1.15rem;
  margin-bottom: 8px;
}

.card h2 a {
  color: #1a1a1a;
  text-decoration: none;
}

.card h2 a:hover {
  text-decoration: underline;
}

.card time {
  display: block;
  font-size: 0.85rem;
  color: #999;
  margin-bottom: 10px;
}

.card p {
  color: #555;
  font-size: 0.95rem;
  line-height: 1.7;
}

.article-timeline {
  list-style: none;
}

.article-timeline li {
  padding: 16px 0;
  border-bottom: 1px solid #eaeaea;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
}

.article-timeline a {
  color: #1a1a1a;
  text-decoration: none;
  font-size: 1.05rem;
}

.article-timeline a:hover {
  text-decoration: underline;
}

.article-timeline time {
  font-size: 0.85rem;
  color: #999;
}

.article-content h1 {
  font-size: 1.6rem;
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-content time {
  display: block;
  color: #999;
  font-size: 0.9rem;
  margin-bottom: 28px;
}

.article-content p {
  margin-bottom: 20px;
  color: #333;
  font-size: 1rem;
  line-height: 1.8;
}

.about p {
  margin-bottom: 16px;
  color: #333;
  font-size: 1rem;
  line-height: 1.8;
}

footer {
  text-align: center;
  padding: 30px 0;
  color: #aaa;
  font-size: 0.85rem;
  border-top: 1px solid #eaeaea;
}