/* ── Light mode (default) ── */
:root {
  --bg-color: #fafafa;
  --text-color: #1a1a1a;
  --text-secondary: #6b6b6b;
  --link-color: #1a6b3c;
  --link-hover: #0d4025;
  --border-color: #e0e0e0;
  --code-bg: #f0f0f0;
  --code-text: #1a1a1a;
  --blockquote-border: #c8c8c8;
  --blockquote-bg: transparent;
  --nav-border: #e0e0e0;
}

/* ── Dark mode ── */
[data-theme="dark"] {
  --bg-color: #1a1a1a;
  --text-color: #e8e8e8;
  --text-secondary: #a0a0a0;
  --link-color: #6ec898;
  --link-hover: #8eddb3;
  --border-color: #333;
  --code-bg: #252525;
  --code-text: #e8e8e8;
  --blockquote-border: #444;
  --blockquote-bg: transparent;
  --nav-border: #333;
}

/* ── Base ── */
*, *::before, *::after {
  box-sizing: border-box;
}

body {
  background-color: var(--bg-color);
  color: var(--text-color);
  max-width: 680px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
  transition: background-color 0.2s ease, color 0.2s ease;
}

/* ── Links ── */
a {
  color: var(--link-color);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--link-hover);
  text-decoration: underline;
}

/* ── Headings ── */
h1 {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1.3;
  margin: 2rem 0 1rem;
  letter-spacing: -0.01em;
}

h2 {
  font-size: 1.5rem;
  font-weight: 600;
  line-height: 1.35;
  margin: 1.8rem 0 0.8rem;
}

h3 {
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.4;
  margin: 1.5rem 0 0.6rem;
}

/* ── Navigation ── */
.site-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 1.2rem;
  margin-bottom: 2rem;
  border-bottom: 1px solid var(--nav-border);
}

.site-nav .nav-links {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.site-nav a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-color);
  text-decoration: none;
  letter-spacing: 0.01em;
}

.site-nav a:hover {
  color: var(--link-color);
  text-decoration: none;
}

/* ── Theme toggle ── */
.theme-toggle {
  background: none;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 0.3rem 0.5rem;
  font-size: 1rem;
  line-height: 1;
  transition: color 0.15s ease, border-color 0.15s ease;
  display: flex;
  align-items: center;
}

.theme-toggle:hover {
  color: var(--text-color);
  border-color: var(--text-secondary);
}

/* ── Content ── */
#content {
  margin-top: 1rem;
}

#content p {
  margin: 1.2rem 0;
}

#content ul, #content ol {
  margin: 1rem 0;
  padding-left: 1.5rem;
}

#content li {
  margin: 0.4rem 0;
}

/* ── Post metadata ── */
.post-date {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin: -0.5rem 0 1.5rem;
}

/* ── Post list ── */
#postmenu {
  margin-top: 2rem;
}

#postmenu h3 {
  font-size: 1.1rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.post-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.post-list-item {
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--border-color);
}

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

.post-list-item a {
  font-size: 1.05rem;
  font-weight: 400;
}

.post-list-item .post-list-date {
  display: block;
  color: var(--text-secondary);
  font-size: 0.85rem;
  margin-top: 0.15rem;
}

/* ── Code blocks ── */
pre {
  background-color: var(--code-bg);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1rem;
  overflow-x: auto;
  margin: 1.5rem 0;
}

code {
  background-color: var(--code-bg);
  color: var(--code-text);
  padding: 0.15em 0.35em;
  border-radius: 3px;
}

pre code {
  background: none;
  padding: 0;
  border-radius: 0;
}

/* ── Images ── */
img {
  display: block;
  width: auto;
  height: auto;
  max-width: 100%;
  max-height: 90%;
  margin: 2rem auto;
  border-radius: 4px;
}

/* ── Blockquotes ── */
blockquote {
  border-left: 3px solid var(--blockquote-border);
  margin: 1.5rem 0;
  padding: 0.5rem 1.2rem;
  color: var(--text-secondary);
  font-style: italic;
  background: var(--blockquote-bg);
}

blockquote p {
  margin: 0.5rem 0;
}

/* ── Horizontal rules ── */
hr {
  border: none;
  border-top: 1px solid var(--border-color);
  margin: 2.5rem 0;
}

/* ── Tags ── */
#tags ul {
  display: inline;
  padding: 0 0 0 0.5rem;
}

#tags ul li {
  display: inline-block;
  padding: 0 0.5rem 0 0;
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* ── Footer ── */
.site-footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
  color: var(--text-secondary);
  font-size: 0.85rem;
  text-align: center;
}

/* ── Contact links (homepage) ── */
.contact-links {
  font-size: 0.95rem;
  margin-top: 1.5rem;
  color: var(--text-secondary);
}

.contact-links a {
  font-weight: 400;
}

/* ── Heading anchors (generated by goldmark) ── */
.anchor {
  color: var(--border-color);
  text-decoration: none;
  font-weight: 300;
  margin-left: 0.3rem;
  opacity: 0;
  transition: opacity 0.15s ease;
}

h1:hover .anchor,
h2:hover .anchor,
h3:hover .anchor,
h4:hover .anchor {
  opacity: 1;
}

.anchor:hover {
  color: var(--link-color);
  text-decoration: none;
}

/* ── Responsive ── */
@media (max-width: 720px) {
  body {
    padding: 1.5rem 1rem;
  }

  h1 {
    font-size: 1.7rem;
  }

  .site-nav {
    flex-wrap: wrap;
    gap: 0.5rem;
  }

  .site-nav .nav-links {
    gap: 1rem;
  }
}