/* ==========================================================
   MYSITE THEME — main.css
   Warm paper feel: cream bg, warm dark text, orange accent
   ========================================================== */

/* ---------- CSS Variables ---------- */
:root {
  --bg:         #faf8f1;
  --bg-alt:     #f3efe4;
  --accent:     #e8871a;
  --accent-h:   #c96e0e;
  --text:       #3a3530;
  --text-muted: #8a7f72;
  --border:     #ddd7c8;
  --max-w:      720px;
  --toc-w:      220px;
  --font:       -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
                "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono:       "SF Mono", "Fira Code", Consolas, "Liberation Mono", monospace;
  --lh:         1.8;
  --r:          4px;
}

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

html { font-size: 16px; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: var(--lh);
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-h); text-decoration: underline; }

img { max-width: 100%; height: auto; display: block; }

/* ---------- Header (non-sticky) ---------- */
.site-header {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 56px;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.site-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  white-space: nowrap;
  margin-right: auto;
  letter-spacing: -0.01em;
  transition: color 0.2s;
}
.site-title:hover { color: var(--accent); text-decoration: none; }

/* ---------- Navigation ---------- */
.site-nav ul {
  list-style: none;
  margin: 0; padding: 0;
  display: flex;
  gap: 0.15rem;
}
.site-nav a {
  color: var(--text-muted);
  font-size: 0.875rem;
  padding: 0.3rem 0.55rem;
  border-radius: var(--r);
  transition: color 0.15s, background 0.15s;
}
.site-nav a:hover,
.site-nav a.active {
  color: var(--accent);
  background: var(--bg-alt);
  text-decoration: none;
}

/* Hamburger — hidden on desktop */
.nav-toggle       { display: none; }
.nav-toggle-label { display: none; cursor: pointer; padding: 0.5rem; flex-direction: column; gap: 4px; }
.nav-toggle-label span {
  display: block;
  width: 22px; height: 2px;
  background: var(--text);
  transition: transform 0.2s, opacity 0.2s;
}

/* ---------- Main: compact centered at --max-w ---------- */
.site-main {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2rem 1.5rem;
  min-height: calc(100vh - 56px - 90px);
  overflow: visible; /* allow absolutely-positioned TOC to extend beyond */
}

/* ---------- Home: Post Cards ---------- */
.post-list { display: flex; flex-direction: column; gap: 2.5rem; }

.post-card {
  border-bottom: 1px solid var(--border);
  padding-bottom: 2.5rem;
}
.post-card:last-child { border-bottom: none; }

.post-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.25rem 0.5rem;
}
.post-category { color: var(--accent); font-size: 0.78rem; }
.post-category:hover { text-decoration: underline; }

/* Homepage post title — larger than in-article h2 */
.post-title { margin: 0 0 0.5rem; font-size: 1.65rem; line-height: 1.3; }
.post-title a {
  color: var(--text);
  display: inline-block;
  transition: color 0.2s, transform 0.18s;
}
.post-title a:hover {
  color: var(--accent);
  text-decoration: none;
  transform: translateX(4px);
}

.post-summary { color: var(--text); margin-bottom: 0.6rem; }

.read-more {
  font-size: 0.875rem;
  color: var(--accent);
  font-weight: 500;
  transition: letter-spacing 0.2s;
}
.read-more:hover { text-decoration: underline; letter-spacing: 0.02em; }

.post-tags { display: flex; flex-wrap: wrap; gap: 0.35rem; margin-top: 0.6rem; }
.tag {
  font-size: 0.76rem;
  color: var(--text-muted);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  padding: 0.12rem 0.5rem;
  border-radius: 2rem;
  transition: color 0.15s, border-color 0.15s, background 0.15s;
}
.tag:hover { color: var(--accent); border-color: var(--accent); background: var(--bg); text-decoration: none; }

/* ---------- Single Post Layout ----------
   Article stays at --max-w centered (same as homepage).
   TOC is absolutely positioned to the right, outside normal flow.
   On viewports < 1160px the TOC is hidden automatically.
   -------------------------------------------------- */
.single-layout {
  display: block;
  position: relative; /* containing block for absolute TOC */
}

/* The article fills site-main's content area normally */
.post-single { min-width: 0; }

/* TOC floats to the right of the article, outside normal flow */
.toc-sidebar {
  position: absolute;
  left: calc(100% + 1.5rem);
  top: 0;
  width: var(--toc-w);
  height: 100%; /* must match article height so sticky has room to scroll */
}

/* TOC inner: sticky, minimal — no box, no border */
.toc-inner {
  position: sticky;
  top: 1.5rem;
  max-height: calc(100vh - 3rem);
  overflow-y: auto;
  font-size: 0.8rem;
  line-height: 1.55;
  padding: 0;
}

.toc-title {
  font-weight: 700;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--text-muted);
  margin: 0 0 0.6rem;
}

#TableOfContents ul { list-style: none; margin: 0; padding: 0; }
#TableOfContents ul ul { padding-left: 0.85rem; }
#TableOfContents a {
  display: block;
  color: var(--text-muted);
  padding: 0.12rem 0 0.12rem 0.5rem;
  border-left: 2px solid transparent;
  transition: color 0.15s, border-color 0.15s;
  text-decoration: none;
  word-break: break-word;
}
#TableOfContents a:hover {
  color: var(--accent);
  border-left-color: var(--accent);
}

/* ---------- Single Post Content ---------- */
.post-header { margin-bottom: 2rem; }
.post-header .post-title {
  font-size: 1.85rem;
  line-height: 1.25;
  margin: 0 0 0.75rem;
  /* Override the translateX animation — title in article header should stay put */
  display: block;
}
.post-header .post-title:hover { transform: none; }
.post-meta-sep { color: var(--border); margin: 0 0.1rem; }
.post-wordcount { font-size: 0.78rem; }

.post-content h1,
.post-content h2,
.post-content h3,
.post-content h4 {
  color: var(--text);
  line-height: 1.3;
  margin-top: 2rem;
  margin-bottom: 0.6rem;
}
.post-content h1 { font-size: 1.6rem; }
.post-content h2 { font-size: 1.35rem; }
.post-content h3 { font-size: 1.1rem; }
.post-content h4 { font-size: 1rem; }

.post-content p { margin: 0 0 1.2rem; }

.post-content a { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }
.post-content a:hover { color: var(--accent-h); }

.post-content blockquote {
  margin: 1.5rem 0;
  padding: 0.75rem 1.25rem;
  border-left: 3px solid var(--accent);
  background: var(--bg-alt);
  color: var(--text-muted);
  border-radius: 0 var(--r) var(--r) 0;
}
.post-content blockquote p:last-child { margin: 0; }

/* Inline code */
.post-content code {
  font-family: var(--mono);
  font-size: 0.875em;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  padding: 0.1em 0.35em;
  border-radius: var(--r);
  color: var(--accent);
}

/* Fenced code blocks (Chroma) */
.post-content .highlight,
.post-content pre {
  margin: 1.5rem 0;
  border-radius: var(--r);
  overflow-x: auto;
  font-size: 0.875rem;
  line-height: 1.6;
}
.post-content .highlight code,
.post-content pre code {
  background: none;
  border: none;
  padding: 0;
  color: inherit;
  font-size: inherit;
}
/* Plain pre (no Chroma) fallback */
.post-content pre:not(.chroma) {
  background: #2d2925;
  color: #f8f4ec;
  padding: 1em 1.25em;
}

.post-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.9rem;
  overflow-x: auto;
  display: block;
}
.post-content th {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  padding: 0.45rem 0.75rem;
  text-align: left;
  font-weight: 600;
}
.post-content td {
  border: 1px solid var(--border);
  padding: 0.45rem 0.75rem;
}
.post-content tr:nth-child(even) td { background: var(--bg-alt); }

.post-content hr {
  border: none;
  border-top: 1.5px dashed var(--accent);
  margin: 2.5rem 0;
  opacity: 0.45;
}

.post-content ul,
.post-content ol { padding-left: 1.5rem; margin: 0 0 1.2rem; }
.post-content li { margin-bottom: 0.25rem; }

.post-content img { border-radius: var(--r); margin: 1rem auto; }

/* ---------- Post Footer ---------- */
.post-footer {
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.post-nav {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}
.post-nav-prev { margin-right: auto; }
.post-nav-next { margin-left: auto; text-align: right; }
.post-nav a { display: flex; flex-direction: column; color: var(--text); text-decoration: none; max-width: 280px; }
.post-nav-label { font-size: 0.76rem; color: var(--text-muted); margin-bottom: 0.2rem; }
.post-nav-title { font-size: 0.875rem; font-weight: 500; color: var(--accent); transition: letter-spacing 0.2s; }
.post-nav a:hover .post-nav-title { text-decoration: underline; letter-spacing: 0.01em; }

/* ---------- Archive / List Pages ---------- */
.page-title {
  font-size: 1.5rem;
  margin: 0 0 1.5rem;
  padding-bottom: 0.4rem;
  border-bottom: 2px solid var(--accent);
  display: inline-block;
}

.archive-count { color: var(--text-muted); font-size: 0.875rem; margin: -1rem 0 1.5rem; }

.archive-year {
  font-size: 1.1rem;
  color: var(--text-muted);
  margin: 1.75rem 0 0.4rem;
  font-weight: 600;
}

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

.archive-item {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 0.3rem 0;
  border-bottom: 1px dashed var(--border);
}
.archive-item:last-child { border-bottom: none; }

.archive-date {
  flex-shrink: 0;
  font-size: 0.8rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
  min-width: 3rem;
}
.archive-link {
  color: var(--text);
  display: inline-block;
  transition: color 0.18s, transform 0.18s;
}
.archive-link:hover {
  color: var(--accent);
  text-decoration: none;
  transform: translateX(3px);
}

/* ---------- Terms Cloud (Tags/Categories) ---------- */
.terms-cloud { display: flex; flex-wrap: wrap; gap: 0.6rem; margin-top: 1rem; }

.terms-item {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 2rem;
  color: var(--text);
  font-size: 0.875rem;
  transition: border-color 0.15s, color 0.15s, background 0.15s, transform 0.15s;
  text-decoration: none;
}
.terms-item:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--bg-alt);
  text-decoration: none;
  transform: translateY(-1px);
}
.terms-count {
  font-size: 0.72rem;
  color: var(--text-muted);
  background: var(--bg-alt);
  border-radius: 1rem;
  padding: 0.05rem 0.4rem;
}

/* ---------- Pagination ---------- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  font-size: 0.875rem;
}
.pagination a {
  color: var(--accent);
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: var(--r);
  transition: background 0.15s, border-color 0.15s;
}
.pagination a:hover {
  background: var(--bg-alt);
  border-color: var(--accent);
  text-decoration: none;
}
.pagination-info { color: var(--text-muted); }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-alt);
  padding: 1.25rem 1.5rem;
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.social-links { display: flex; gap: 0.75rem; align-items: center; }

.social-link {
  color: var(--text-muted);
  display: flex;
  align-items: center;
  transition: color 0.15s, transform 0.15s;
}
.social-link:hover { color: var(--accent); text-decoration: none; transform: translateY(-2px); }
.social-link svg { fill: currentColor; }

.copyright { font-size: 0.78rem; color: var(--text-muted); }
.copyright a { color: var(--text-muted); }
.copyright a:hover { color: var(--accent); }

/* ---------- 404 ---------- */
.page-404 { text-align: center; padding: 6rem 1.5rem; }
.page-404 h1 { font-size: 5rem; margin: 0; color: var(--accent); line-height: 1; }
.page-404 p  { color: var(--text-muted); font-size: 1.1rem; margin: 1rem 0 2rem; }

/* ---------- Back to Top ---------- */
.back-to-top {
  position: fixed;
  bottom: 1.75rem;
  right: 1.75rem;
  width: 2.4rem;
  height: 2.4rem;
  background: var(--accent);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  line-height: 1;
  text-decoration: none;
  box-shadow: 0 2px 10px rgba(0,0,0,0.18);
  opacity: 0;
  pointer-events: none;
  transform: translateY(6px);
  transition: opacity 0.25s, transform 0.25s;
  z-index: 200;
}
.back-to-top.visible { opacity: 0.85; pointer-events: auto; transform: translateY(0); }
.back-to-top:hover   { opacity: 1; color: #fff; text-decoration: none; }

/* ---------- Responsive ---------- */

/* Hide TOC when viewport is too narrow to show it beside the article
   Threshold: --max-w (720) + 2*padding (48) + gap (24) + --toc-w (220) ≈ 1012px
   Add a small buffer → 1060px                                              */
@media (max-width: 1060px) {
  .toc-sidebar { display: none; }
}

/* Mobile */
@media (max-width: 640px) {
  .nav-toggle-label { display: flex; order: 2; }

  .header-inner { position: relative; } /* containing block for dropdown */

  .site-nav {
    display: none;
    position: absolute;
    top: 56px; left: 0; right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 0.5rem 1.5rem 1rem;
    box-shadow: 0 4px 12px rgba(0,0,0,0.07);
    z-index: 99;
  }
  .site-nav ul  { flex-direction: column; gap: 0; }
  .site-nav li  { border-bottom: 1px solid var(--border); }
  .site-nav li:last-child { border-bottom: none; }
  .site-nav a   { padding: 0.6rem 0.25rem; display: block; }

  .nav-toggle:checked ~ .site-nav { display: block; }

  .nav-toggle:checked + .nav-toggle-label span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
  .nav-toggle:checked + .nav-toggle-label span:nth-child(2) { opacity: 0; }
  .nav-toggle:checked + .nav-toggle-label span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

  .site-main { padding: 1.25rem 1rem; }
  .post-header .post-title { font-size: 1.5rem; }
  .post-title { font-size: 1.4rem; }
  .post-nav { flex-direction: column; }
  .post-nav-next { text-align: left; }
  .post-nav a { max-width: 100%; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
}

/* Print */
@media print {
  .site-header, .site-footer, .post-nav, .toc-sidebar, .nav-toggle, .nav-toggle-label, .back-to-top { display: none; }
  body { font-size: 12pt; color: #000; background: #fff; }
  a { color: #000; text-decoration: underline; }
}