:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f5f7fa;
  --color-text: #1a1f29;
  --color-text-muted: #4b5563;
  --color-accent: #2952cc;
  --color-border: #e2e5eb;
  --max-width: 960px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Malgun Gothic", sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.site-header {
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  background: var(--color-bg);
  z-index: 10;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.wordmark {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--color-text);
  text-decoration: none;
}

.nav a {
  margin-left: 24px;
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.95rem;
}

.nav a:hover {
  color: var(--color-accent);
}

.hero {
  padding: 96px 0 72px;
  text-align: center;
}

.hero h1 {
  font-size: 2.2rem;
  margin: 0 0 16px;
}

.hero-sub {
  color: var(--color-text-muted);
  max-width: 640px;
  margin: 0 auto 32px;
}

.cta {
  display: inline-block;
  padding: 12px 28px;
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
  border-radius: 6px;
  font-weight: 600;
}

.section {
  padding: 64px 0;
}

.section.alt {
  background: var(--color-bg-alt);
}

.section h2 {
  font-size: 1.6rem;
  margin-bottom: 32px;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 24px;
}

.card h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
}

.card p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 24px;
}

.timeline li {
  border-left: 3px solid var(--color-accent);
  padding-left: 20px;
}

.timeline h3 {
  margin: 0 0 4px;
  font-size: 1.1rem;
}

.timeline p {
  margin: 0;
  color: var(--color-text-muted);
}

.tags {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.tags li {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  padding: 6px 16px;
  font-size: 0.9rem;
  color: var(--color-text);
}

.badges {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 4px;
}

.badge {
  display: inline-block;
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  padding: 6px 14px;
  font-size: 0.85rem;
  color: var(--color-text);
}

.founder h3 {
  margin: 0 0 4px;
  font-size: 1.2rem;
}

.founder-title {
  margin: 0 0 16px;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.founder-badges {
  margin-bottom: 20px;
}

.founder-badges li {
  background: var(--color-bg);
}

.founder p {
  max-width: 640px;
}

.link-icon {
  color: var(--color-accent);
  text-decoration: none;
  font-size: 0.9em;
}

.site-footer {
  padding: 32px 0;
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--color-border);
}

.page-title {
  font-size: 1.9rem;
  margin: 0 0 8px;
}

.page-sub {
  color: var(--color-text-muted);
  margin: 0 0 32px;
}

.post-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 24px;
}

.post-list li {
  border-left: 3px solid var(--color-accent);
  padding-left: 20px;
}

.post-title {
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--color-text);
  text-decoration: none;
}

.post-title:hover {
  color: var(--color-accent);
}

.post-summary-en {
  margin: 4px 0;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.post-list time,
.post-header time {
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.post {
  max-width: 720px;
}

.post-header h1 {
  font-size: 1.9rem;
  line-height: 1.3;
  margin: 0 0 8px;
}

.summary-en {
  background: var(--color-bg-alt);
  border-left: 4px solid var(--color-accent);
  border-radius: 4px;
  padding: 16px 20px;
  margin: 32px 0;
}

.summary-en p {
  margin: 0;
}

.post-body h2 {
  font-size: 1.4rem;
  margin: 40px 0 12px;
}

.post-body h3 {
  font-size: 1.15rem;
  margin: 28px 0 8px;
}

.post-body a {
  color: var(--color-accent);
}

.post-body img {
  max-width: 100%;
  height: auto;
}

.post-body pre {
  overflow-x: auto;
  padding: 16px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 0.875rem;
  line-height: 1.5;
}

.post-body code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.9em;
}

.post-body :not(pre) > code {
  background: var(--color-bg-alt);
  padding: 2px 6px;
  border-radius: 4px;
}

.post-body table {
  display: block;
  overflow-x: auto;
  border-collapse: collapse;
}

.post-body th,
.post-body td {
  border: 1px solid var(--color-border);
  padding: 8px 12px;
  text-align: left;
}

.post-body blockquote {
  margin: 0;
  padding-left: 16px;
  border-left: 3px solid var(--color-border);
  color: var(--color-text-muted);
}

.post-footer {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
}

.post-footer a:not(.cta) {
  color: var(--color-accent);
}

.section-bordered {
  border-top: 1px solid var(--color-border);
}

.more-link {
  margin: 24px 0 0;
}

.more-link a {
  color: var(--color-accent);
  font-weight: 600;
  text-decoration: none;
}

@media (max-width: 640px) {
  .header-inner {
    flex-direction: column;
    height: auto;
    padding: 12px 0;
    gap: 8px;
  }
  .nav a {
    margin: 0 10px;
    white-space: nowrap;
  }
  .hero {
    padding: 64px 0 48px;
  }
  .hero h1 {
    font-size: 1.6rem;
  }
  .page-title,
  .post-header h1 {
    font-size: 1.5rem;
  }
}

.post-links {
  margin: 4px 0 0;
  font-size: 0.9rem;
}