/* ===== Medium-Inspired Minimal Styles ===== */

:root {
  --font-ui: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-body: Georgia, Cambria, "Times New Roman", Times, serif;
  --font-title: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --bg: #ffffff;
  --bg-subtle: #fafafa;
  --text: #242424;
  --text-secondary: #6b6b6b;
  --text-muted: #999999;
  --border: #e6e6e6;
  --link: #242424;
  --link-hover: #6b6b6b;
  --max-content: 740px;
  --max-home: 1120px;
  --line-height-body: 1.75;
}

/* Reset */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }

body {
  font-family: var(--font-ui);
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

/* ===== Navigation ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  height: 60px;
}
.header-inner {
  max-width: var(--max-home);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.site-logo {
  font-family: var(--font-title);
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  text-decoration: none;
  letter-spacing: 0;
}
nav { display: flex; align-items: center; gap: 24px; }
nav a {
  font-size: 14px;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.15s;
}
nav a:hover { color: var(--text); }

/* ===== Homepage ===== */
.home-container {
  max-width: var(--max-home);
  margin: 0 auto;
  padding: 48px 24px;
}
.home-header {
  margin-bottom: 40px;
}
.home-header h1 {
  font-family: var(--font-title);
  font-size: 32px;
  font-weight: 700;
  letter-spacing: 0;
  margin-bottom: 8px;
}
.home-header p {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 540px;
}

/* Article Feed */
.article-feed { list-style: none; }
.article-feed-item {
  display: block;
  padding: 28px 0;
  border-bottom: 1px solid var(--border);
  text-decoration: none;
  color: inherit;
  display: grid;
  grid-template-columns: 1fr 140px;
  gap: 24px;
  align-items: start;
}
.article-feed-item:first-child { padding-top: 0; }
.article-feed-item:last-child { border-bottom: none; }

.article-feed-body { min-width: 0; }
.article-feed-category {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.8px;
  margin-bottom: 8px;
  display: block;
}
.article-feed-title {
  font-family: var(--font-title);
  font-size: 22px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 8px;
  transition: color 0.15s;
}
.article-feed-item:hover .article-feed-title { color: var(--text-secondary); }
.article-feed-excerpt {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 10px;
}
.article-feed-meta {
  font-size: 13px;
  color: var(--text-muted);
}
.article-feed-thumb {
  width: 140px;
  height: 140px;
  border-radius: 4px;
  background: var(--bg-subtle);
  background-size: cover;
  background-position: center;
}

/* ===== Article Page ===== */
.article-page {
  max-width: var(--max-content);
  margin: 0 auto;
  padding: 48px 24px 80px;
}
.article-back {
  display: inline-block;
  font-size: 14px;
  color: var(--text-secondary);
  text-decoration: none;
  margin-bottom: 32px;
  transition: color 0.15s;
}
.article-back:hover { color: var(--text); }
.article-category {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.8px;
  margin-bottom: 16px;
  display: block;
}
.article-title {
  font-family: var(--font-title);
  font-size: 42px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: 0;
  margin-bottom: 16px;
}
.article-meta {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 32px;
}
.article-meta .dot { margin: 0 8px; }

.article-cover {
  width: calc(100% + 80px);
  max-width: 880px;
  margin: 0 -40px 40px -40px;
  border-radius: 4px;
  display: block;
  aspect-ratio: 1200 / 630;
  object-fit: cover;
  background: var(--bg-subtle);
}

.article-body {
  font-family: var(--font-body);
  font-size: 19px;
  line-height: var(--line-height-body);
  color: var(--text);
}
.article-body h2 {
  font-family: var(--font-title);
  font-size: 26px;
  font-weight: 700;
  line-height: 1.3;
  margin: 48px 0 16px;
  padding-top: 4px;
  letter-spacing: 0;
}
.article-body h3 {
  font-family: var(--font-title);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.3;
  margin: 36px 0 12px;
}
.article-body p { margin-bottom: 20px; }
.article-body a { color: var(--text); text-decoration: underline; text-underline-offset: 2px; }
.article-body a:hover { color: var(--text-secondary); }

.article-body blockquote {
  margin: 32px -24px;
  padding: 4px 0 4px 24px;
  border-left: 3px solid var(--border);
  color: var(--text-secondary);
  font-style: italic;
  line-height: 1.6;
}
.article-body blockquote cite {
  display: block;
  margin-top: 10px;
  font-size: 14px;
  color: var(--text-muted);
  font-style: normal;
}

.article-body ul, .article-body ol {
  padding-left: 28px;
  margin-bottom: 20px;
}
.article-body li { margin-bottom: 6px; }

.article-body table {
  width: calc(100% + 80px);
  margin: 32px -40px;
  border-collapse: collapse;
  font-family: var(--font-ui);
  font-size: 14px;
  line-height: 1.5;
}
.article-body table th {
  text-align: left;
  font-weight: 600;
  padding: 10px 14px;
  border-bottom: 2px solid var(--border);
  color: var(--text);
}
.article-body table td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--border);
  color: var(--text-secondary);
  vertical-align: top;
}
.article-body table tr:last-child td { border-bottom: none; }

.article-body pre {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 20px;
  margin: 24px 0;
  font-size: 14px;
  font-family: "SF Mono", Monaco, "Cascadia Code", monospace;
  overflow-x: auto;
  line-height: 1.5;
}
.article-body code {
  font-size: 0.85em;
  background: var(--bg-subtle);
  padding: 2px 6px;
  border-radius: 3px;
  font-family: "SF Mono", Monaco, "Cascadia Code", monospace;
}

/* Data Cards */
.article-body .data-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin: 32px 0;
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow: hidden;
}
.article-body .data-card {
  background: var(--bg-subtle);
  padding: 20px;
  text-align: center;
}
.article-body .data-card + .data-card { border-left: 1px solid var(--border); }
.article-body .data-card .value {
  font-family: var(--font-title);
  font-size: 28px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.1;
  margin-bottom: 6px;
}
.article-body .data-card .label {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Highlight box */
.article-body .highlight-box {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 20px 24px;
  margin: 24px 0;
}
.article-body .highlight-box h4 {
  font-family: var(--font-title);
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
}
.article-body .highlight-box p { font-size: 15px; margin-bottom: 0; }

/* Company card */
.article-body .company-card {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 20px 24px;
  margin-bottom: 16px;
}
.article-body .company-card h3 { margin-top: 0; font-size: 18px; }
.article-body .company-card .desc { font-size: 15px; margin-bottom: 8px; }
.article-body .company-card .dilemma {
  font-size: 13px;
  color: #c0392b;
  background: #fdedec;
  padding: 8px 12px;
  border-radius: 3px;
  margin-top: 8px;
}

/* Original link */
.article-body .original-link {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  font-family: var(--font-ui);
  font-size: 14px;
}
.article-body .original-link a {
  color: var(--text-secondary);
  text-decoration: none;
}
.article-body .original-link a:hover { color: var(--text); text-decoration: underline; }

/* Article Navigation */
.article-nav {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  font-size: 14px;
}
.article-nav a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.15s;
}
.article-nav a:hover { color: var(--text); }
.article-nav .nav-prev { text-align: left; }
.article-nav .nav-home { text-align: center; }
.article-nav .nav-next { text-align: right; }

/* ===== About Page ===== */
.about-page {
  max-width: var(--max-content);
  margin: 0 auto;
  padding: 60px 24px;
}
.about-page h1 {
  font-family: var(--font-title);
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 12px;
  letter-spacing: 0;
}
.about-page .subtitle {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 40px;
}
.about-page h2 {
  font-family: var(--font-title);
  font-size: 20px;
  font-weight: 600;
  margin: 40px 0 12px;
}
.about-page p {
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 12px;
}
.about-page .flow-steps { list-style: none; padding: 0; margin: 0; }
.about-page .flow-steps li {
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
  font-size: 15px;
  color: var(--text);
}
.about-page .flow-steps li:last-child { border-bottom: none; }
.about-page .flow-steps li strong {
  display: inline-block;
  width: 32px;
  height: 32px;
  line-height: 32px;
  text-align: center;
  background: var(--bg-subtle);
  border-radius: 50%;
  margin-right: 12px;
  font-size: 13px;
  color: var(--text-secondary);
}

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 24px;
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 40px;
}
.site-footer a { color: var(--text-secondary); text-decoration: none; }
.site-footer a:hover { color: var(--text); text-decoration: underline; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .home-container { padding: 32px 20px; }
  .home-header h1 { font-size: 26px; }
  .article-feed-item {
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 24px 0;
  }
  .article-feed-thumb {
    width: 100%;
    height: auto;
    aspect-ratio: 1200 / 630;
    order: -1;
  }
  .article-feed-title { font-size: 18px; }

  .article-page { padding: 32px 20px 60px; }
  .article-title { font-size: 30px; }
  .article-cover {
    width: calc(100% + 40px);
    margin: 0 -20px 28px -20px;
  }
  .article-body { font-size: 17px; }
  .article-body table { width: 100%; margin: 24px 0; display: block; overflow-x: auto; }
  .article-body .data-cards { grid-template-columns: 1fr 1fr; }
  .article-body blockquote { margin: 24px 0; }
  .article-nav { flex-direction: column; gap: 12px; align-items: center; }
  nav { gap: 16px; }
  nav a { font-size: 13px; }
}

@media (max-width: 375px) {
  .home-container { padding: 24px 16px; }
  .article-feed-title { font-size: 16px; }
  .article-feed-excerpt { font-size: 14px; }
  .article-title { font-size: 26px; }
  .article-body { font-size: 16px; }
  .article-body .data-cards { grid-template-columns: 1fr; }
}