:root {
  --fg: #1a1a1a;
  --fg-secondary: #555;
  --fg-tertiary: #888;
  --bg: #fafaf8;
  --border: #ddd;
  --link: #1a1a1a;
  --link-hover: #000;
  --accent: #c44;
  --mono: 'IBM Plex Mono', monospace;
  --serif: 'Source Serif 4', Georgia, serif;
}

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

body {
  font-family: var(--serif);
  background: var(--bg);
  color: var(--fg);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 680px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ── Header ── */
header {
  border-bottom: 1px solid var(--border);
  padding: 28px 0 24px;
  margin-bottom: 48px;
}

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

.site-title {
  font-family: var(--mono);
  font-size: 15px;
  font-weight: 500;
  text-decoration: none;
  color: var(--fg);
  letter-spacing: -0.3px;
}

nav a {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--fg-tertiary);
  text-decoration: none;
  margin-left: 24px;
  transition: color 0.15s;
}

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

/* ── Intro ── */
.intro {
  margin-bottom: 56px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--border);
}

.intro p {
  color: var(--fg-secondary);
  font-size: 17px;
  max-width: 560px;
}

.intro-links {
  margin-top: 16px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--fg-tertiary);
}

.intro-links a {
  color: var(--fg-secondary);
  text-decoration: none;
  border-bottom: 1px solid var(--border);
  transition: border-color 0.15s;
}

.intro-links a:hover {
  border-color: var(--fg);
}

.intro-links span {
  margin: 0 8px;
  color: var(--border);
}

/* ── Section Label ── */
.section-label {
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--fg-tertiary);
  margin-bottom: 24px;
}

/* ── Post List ── */
.post-list {
  list-style: none;
}

.post-item {
  padding: 16px 0;
  border-bottom: 1px solid #eee;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 24px;
}

.post-item:last-child {
  border-bottom: none;
}

.post-title-link {
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 600;
  color: var(--fg);
  text-decoration: none;
  line-height: 1.4;
  transition: color 0.15s;
}

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

.post-meta {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--fg-tertiary);
  white-space: nowrap;
  flex-shrink: 0;
}

.post-summary {
  margin-top: 6px;
  font-size: 14.5px;
  color: var(--fg-secondary);
  line-height: 1.6;
}

.post-tag {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--fg-tertiary);
  margin-top: 4px;
}

/* ── Article ── */
.article-back {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--fg-tertiary);
  text-decoration: none;
  display: inline-block;
  margin-bottom: 32px;
  transition: color 0.15s;
}

.article-back:hover { color: var(--fg); }

.article-header {
  margin-bottom: 40px;
}

.article-header h1 {
  font-family: var(--serif);
  font-size: 32px;
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.5px;
  margin-bottom: 12px;
}

.article-meta {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--fg-tertiary);
}

.article-body h2 {
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 600;
  margin-top: 40px;
  margin-bottom: 16px;
  letter-spacing: -0.3px;
}

.article-body h3 {
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 600;
  margin-top: 32px;
  margin-bottom: 12px;
}

.article-body p {
  margin-bottom: 18px;
  font-size: 16.5px;
  color: var(--fg);
}

.article-body a {
  color: var(--fg);
  border-bottom: 1px solid var(--border);
  text-decoration: none;
  transition: border-color 0.15s;
}

.article-body a:hover {
  border-color: var(--fg);
}

.article-body code {
  font-family: var(--mono);
  font-size: 14px;
  background: #f0f0ec;
  padding: 2px 6px;
  border-radius: 3px;
}

.article-body pre {
  background: #1a1a1a;
  color: #d4d4d4;
  padding: 20px 24px;
  border-radius: 4px;
  overflow-x: auto;
  margin: 24px 0;
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.6;
}

.article-body pre code {
  background: none;
  padding: 0;
  border-radius: 0;
  font-size: 13.5px;
}

.article-body ul, .article-body ol {
  margin-bottom: 18px;
  padding-left: 24px;
}

.article-body li {
  margin-bottom: 6px;
  font-size: 16.5px;
}

.article-body blockquote {
  border-left: 3px solid var(--border);
  padding-left: 20px;
  margin: 28px 0;
  color: var(--fg-secondary);
  font-style: italic;
}

.article-body img {
  max-width: 100%;
  border-radius: 4px;
  margin: 24px 0;
}

/* Decision Box - custom component */
.decision-box {
  border: 1px solid var(--border);
  padding: 20px 24px;
  margin: 28px 0;
  background: #fff;
}

.decision-box .decision-label {
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--fg-tertiary);
  margin-bottom: 10px;
}

.decision-box p {
  font-size: 15px;
  margin-bottom: 8px;
}

.decision-box p:last-child {
  margin-bottom: 0;
}

/* ── Page Content (about, projects) ── */
.page-content p {
  font-size: 17px;
  color: var(--fg-secondary);
  margin-bottom: 16px;
  max-width: 580px;
}

.page-content a {
  color: var(--fg);
  text-decoration: none;
  border-bottom: 1px solid var(--border);
  transition: border-color 0.15s;
}

.page-content a:hover {
  border-color: var(--fg);
}

.project-list {
  margin-top: 40px;
}

.project-item {
  padding: 20px 0;
  border-bottom: 1px solid #eee;
}

.project-item:first-child {
  border-top: 1px solid #eee;
}

.project-name {
  font-weight: 600;
  font-size: 17px;
  margin-bottom: 4px;
}

.project-name a {
  color: var(--fg);
  text-decoration: none;
  border-bottom: 1px solid var(--border);
}

.project-name a:hover {
  border-color: var(--fg);
}

.project-desc {
  font-size: 14.5px;
  color: var(--fg-secondary);
}

.project-tech {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--fg-tertiary);
  margin-top: 4px;
}

/* ── Footer ── */
footer {
  margin-top: 80px;
  padding: 24px 0;
  border-top: 1px solid var(--border);
  font-family: var(--mono);
  font-size: 12px;
  color: var(--fg-tertiary);
}

/* ── Mobile ── */
@media (max-width: 600px) {
  .post-item {
    flex-direction: column;
    gap: 4px;
  }
  .article-header h1 {
    font-size: 26px;
  }
  header .container {
    flex-direction: column;
    gap: 12px;
  }
  nav a:first-child {
    margin-left: 0;
  }
}