/* ── Reset & Base ── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  height: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 1.1rem;
  line-height: 1.72;
  color: #333;
  background: #fff;
  min-height: 100%;
}

/* ── Layout ── */
.post-container {
  max-width: 640px;
  margin: 0 auto;
  padding: 3rem 1.5rem 4rem;
}

/* ── Back Link ── */
.post-back {
  display: inline-block;
  font-family: "SF Mono", SFMono-Regular, ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.85rem;
  color: #aaa;
  text-decoration: none;
  margin-bottom: 2.5rem;
  transition: color 0.2s ease;
}

.post-back:hover {
  color: #5B5EA6;
}

/* ── Post Header ── */
.post-header {
  margin-bottom: 2.5rem;
}

.post-date {
  font-family: "SF Mono", SFMono-Regular, ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.78rem;
  color: #aaa;
  letter-spacing: 0.02em;
  margin-bottom: 0.5rem;
}

.post-title {
  font-size: 1.85rem;
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: #111;
}

.post-header-rule {
  margin-top: 1.5rem;
  height: 1px;
  border: none;
  background: #eee;
}

/* ── Article Content ── */
.post-content h1 {
  font-size: 1.65rem;
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: #111;
  margin-top: 2.5rem;
  margin-bottom: 0.75rem;
}

.post-content h2 {
  font-size: 1.35rem;
  font-weight: 650;
  line-height: 1.35;
  color: #1a1a1a;
  margin-top: 2.25rem;
  margin-bottom: 0.6rem;
}

.post-content h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: #1a1a1a;
  margin-top: 2rem;
  margin-bottom: 0.5rem;
}

.post-content h4, .post-content h5, .post-content h6 {
  font-size: 1rem;
  font-weight: 600;
  color: #333;
  margin-top: 1.75rem;
  margin-bottom: 0.5rem;
}

.post-content p {
  margin-bottom: 1.25rem;
}

/* ── Links ── */
.post-content a {
  color: #5B5EA6;
  text-decoration: none;
  border-bottom: 1px solid #d4d4f7;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.post-content a:hover {
  color: #3d3f7a;
  border-bottom-color: #5B5EA6;
}

/* ── Lists ── */
.post-content ul,
.post-content ol {
  margin-bottom: 1.25rem;
  padding-left: 1.5rem;
}

.post-content li {
  margin-bottom: 0.4rem;
}

.post-content li > ul,
.post-content li > ol {
  margin-top: 0.3rem;
  margin-bottom: 0.3rem;
}

/* ── Images ── */
.post-content img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 1.75rem auto;
  border-radius: 4px;
}

/* ── Blockquotes ── */
.post-content blockquote {
  border-left: 3px solid #5B5EA6;
  padding: 0.1rem 0 0.1rem 1.25rem;
  margin: 1.5rem 0;
  color: #555;
  font-style: italic;
}

.post-content blockquote p {
  margin-bottom: 0.5rem;
}

.post-content blockquote p:last-child {
  margin-bottom: 0;
}

/* ── Code ── */
.post-content code {
  font-family: "SF Mono", SFMono-Regular, ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.88em;
  background: #f5f5f5;
  color: #333;
  padding: 0.15em 0.4em;
  border-radius: 3px;
}

.post-content pre {
  margin: 1.5rem 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.post-content pre code,
.post-content div.highlighter-rouge code {
  display: block;
  background: #1e1e2e;
  color: #cdd6f4;
  padding: 1.1rem 1.25rem;
  border-radius: 6px;
  font-size: 0.85rem;
  line-height: 1.55;
  white-space: pre;
  overflow-x: auto;
}

/* ── Tables ── */
.post-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.92rem;
}

.post-content th,
.post-content td {
  border: 1px solid #e5e5e5;
  padding: 0.6rem 0.75rem;
  text-align: left;
}

.post-content th {
  background: #fafafa;
  font-weight: 600;
  color: #1a1a1a;
}

/* ── Horizontal Rules ── */
.post-content hr {
  border: none;
  height: 1px;
  background: #eee;
  margin: 2.25rem 0;
}

/* ── Strong & Emphasis ── */
.post-content strong {
  font-weight: 650;
  color: #1a1a1a;
}

.post-content em {
  font-style: italic;
}

/* ── Post Footer ── */
.post-footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid #f0f0f0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.post-footer a {
  font-family: "SF Mono", SFMono-Regular, ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.82rem;
  color: #aaa;
  text-decoration: none;
  transition: color 0.2s ease;
}

.post-footer a:hover {
  color: #5B5EA6;
}

.post-footer-copy {
  font-family: "SF Mono", SFMono-Regular, ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.72rem;
  color: #ccc;
}

/* ── Responsive ── */
@media (max-width: 480px) {
  body {
    font-size: 1.05rem;
    line-height: 1.7;
  }

  .post-container {
    padding: 2rem 1.25rem 3rem;
  }

  .post-title {
    font-size: 1.55rem;
  }

  .post-content h1 {
    font-size: 1.4rem;
  }

  .post-content h2 {
    font-size: 1.2rem;
  }

  .post-content pre code,
  .post-content div.highlighter-rouge code {
    font-size: 0.8rem;
    padding: 0.9rem 1rem;
  }
}