:root {
  --bg: #ffffff;
  --bg-elev: #f6f7f9;
  --text: #1a1a1a;
  --text-muted: #6b7280;
  --border: #e5e7eb;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --code-bg: #f3f4f6;
  --code-text: #b91c1c;
  --pre-bg: #1e293b;
  --pre-text: #e2e8f0;
  --tag-bg: #eef2ff;
  --tag-text: #4338ca;
  --max: 720px;
}

[data-theme="dark"] {
  --bg: #0f1115;
  --bg-elev: #171a21;
  --text: #e5e7eb;
  --text-muted: #9ca3af;
  --border: #262a33;
  --accent: #60a5fa;
  --accent-hover: #93c5fd;
  --code-bg: #1c212b;
  --code-text: #f87171;
  --pre-bg: #0b0e13;
  --pre-text: #e2e8f0;
  --tag-bg: #1e2433;
  --tag-text: #93c5fd;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.7;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  transition: background 0.2s ease, color 0.2s ease;
}

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

/* Header */
.site-header {
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(8px);
  z-index: 10;
}
.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
  font-size: 17px;
}
.brand img {
  width: 30px;
  height: 30px;
  border-radius: 50%;
}
.theme-toggle {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  color: var(--text);
  width: 38px;
  height: 38px;
  border-radius: 10px;
  cursor: pointer;
  font-size: 17px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s ease;
}
.theme-toggle:hover { background: var(--border); }

/* Main */
main { padding: 56px 0 40px; }

/* Hero (home) */
.hero { text-align: center; margin-bottom: 48px; }
.hero img {
  width: 110px;
  height: 110px;
  border-radius: 50%;
  border: 3px solid var(--border);
  margin-bottom: 20px;
}
.hero h1 { font-size: 2.4rem; margin: 0 0 8px; letter-spacing: -0.02em; }
.hero p { color: var(--text-muted); font-size: 1.15rem; margin: 0; }

.hero-meta {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px 18px;
}
.hero-meta li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.95rem;
  color: var(--text-muted);
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 6px 14px;
}
.hero-meta svg { color: var(--accent); flex-shrink: 0; }
.hero-meta a { color: var(--text); text-decoration: none; font-weight: 600; }
.hero-meta a:hover { color: var(--accent); }

/* Post list */
.section-title {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin: 0 0 16px;
}
.post-list { list-style: none; padding: 0; margin: 0; }
.post-list li {
  border-bottom: 1px solid var(--border);
}
.post-list li:first-child { border-top: 1px solid var(--border); }
.post-list a {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 18px 4px;
  text-decoration: none;
  color: var(--text);
  transition: color 0.15s ease, padding 0.15s ease;
}
.post-list a:hover { color: var(--accent); padding-left: 10px; }
.post-list .title { font-weight: 600; font-size: 1.1rem; }
.post-list .date { font-size: 0.85rem; color: var(--text-muted); }

/* Article */
article h1 {
  font-size: 2.1rem;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin: 0 0 8px;
}
.post-meta { color: var(--text-muted); font-size: 0.9rem; margin-bottom: 36px; }
article h2 {
  font-size: 1.4rem;
  margin: 40px 0 14px;
  letter-spacing: -0.01em;
}
article p { margin: 18px 0; }
article ul { padding-left: 22px; }
article li { margin: 8px 0; }
article a { color: var(--accent); text-decoration: none; }
article a:hover { color: var(--accent-hover); text-decoration: underline; }

code {
  background: var(--code-bg);
  color: var(--code-text);
  padding: 2px 6px;
  border-radius: 5px;
  font-size: 0.88em;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}
pre {
  background: var(--pre-bg);
  color: var(--pre-text);
  padding: 18px 20px;
  border-radius: 10px;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.5;
}
pre code {
  background: none;
  color: inherit;
  padding: 0;
  font-size: inherit;
}

blockquote {
  border-left: 3px solid var(--accent);
  margin: 18px 0;
  padding: 4px 18px;
  color: var(--text-muted);
  background: var(--bg-elev);
  border-radius: 0 8px 8px 0;
}

/* Tags */
.tags { margin: 36px 0 0; display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.tags .label { font-weight: 600; font-size: 0.85rem; margin-right: 4px; }
.tag {
  background: var(--tag-bg);
  color: var(--tag-text);
  font-size: 0.8rem;
  padding: 3px 10px;
  border-radius: 999px;
  text-decoration: none;
}

/* Post navigation */
.post-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}
.post-nav a {
  color: var(--accent);
  text-decoration: none;
  font-size: 0.95rem;
  max-width: 48%;
}
.post-nav a:hover { text-decoration: underline; }
.post-nav .next { text-align: right; margin-left: auto; }

.back-link {
  display: inline-block;
  margin-bottom: 28px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
}
.back-link:hover { color: var(--accent); }

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 64px;
  padding: 32px 0;
}
.site-footer .wrap {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}
.site-footer .connect { display: flex; gap: 18px; }
.site-footer a { color: var(--text-muted); text-decoration: none; font-size: 0.9rem; }
.site-footer a:hover { color: var(--accent); }
.site-footer .copy { color: var(--text-muted); font-size: 0.85rem; }
.site-footer .disclaimer { font-style: italic; opacity: 0.8; }

@media (max-width: 600px) {
  body { font-size: 16px; }
  .hero h1 { font-size: 2rem; }
  article h1 { font-size: 1.7rem; }
}