/* ============================================
   FEATURES CSS — Progress, TOC, Friends,
   Guestbook, RSS, Comments, Multilingual
   ============================================ */

/* ── Reading Progress Bar ── */
.reading-progress {
  position: fixed;
  top: 0; left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  z-index: 9999;
  box-shadow: 0 0 10px var(--accent-glow);
  transition: width 0.08s linear;
  pointer-events: none;
}

/* ── Post Layout with TOC ── */
.post-outer {
  padding-top: var(--nav-height);
  min-height: 100vh;
}

.post-with-toc {
  display: grid;
  grid-template-columns: 1fr 240px;
  gap: 56px;
  max-width: 1080px;
  margin: 0 auto;
  padding: 60px 24px 100px;
  align-items: start;
}

/* ── TOC Sidebar ── */
.toc-sidebar {
  position: sticky;
  top: calc(var(--nav-height) + 24px);
  max-height: calc(100vh - var(--nav-height) - 48px);
  overflow-y: auto;
}

.toc-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
}

.toc-header {
  font-size: 0.7rem;
  font-family: var(--font-mono);
  color: var(--accent);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.toc-header::before {
  content: '';
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 6px var(--accent-glow);
  flex-shrink: 0;
}

.toc-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.toc-item {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  padding: 5px 8px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
  color: var(--text-secondary);
  font-size: 0.8rem;
  line-height: 1.4;
  border: 1px solid transparent;
}
.toc-item:hover {
  color: var(--accent);
  background: var(--accent-dim);
}
.toc-item.active {
  color: var(--accent);
  background: var(--accent-dim);
  border-color: rgba(0,212,255,0.2);
}
.toc-item.h3 { padding-left: 20px; font-size: 0.75rem; }

.toc-num {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--text-muted);
  flex-shrink: 0;
  margin-top: 2px;
}

/* Mobile TOC toggle */
.toc-mobile-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 24px;
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--text-secondary);
  width: 100%;
  justify-content: space-between;
  transition: all var(--transition);
}
.toc-mobile-toggle:hover { border-color: var(--accent); color: var(--accent); }
.toc-mobile-toggle span.arrow { transition: transform 0.2s; }
.toc-mobile-toggle.open span.arrow { transform: rotate(180deg); }

.toc-mobile-panel {
  display: none;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
  margin-bottom: 24px;
}
.toc-mobile-panel.open { display: block; }

/* ── Multilingual Article Switcher ── */
.lang-switcher-post {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}
.lang-switcher-post-label {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  letter-spacing: 0.08em;
}
.lang-post-btn {
  padding: 4px 14px;
  border-radius: 999px;
  font-size: 0.8rem;
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font-mono);
}
.lang-post-btn:hover { border-color: var(--accent); color: var(--accent); }
.lang-post-btn.current {
  background: var(--accent-dim);
  border-color: var(--accent);
  color: var(--accent);
}

/* ── Giscus Comments ── */
.comments-section {
  margin-top: 60px;
  padding-top: 40px;
  border-top: 1px solid var(--border);
}
.comments-header {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--accent);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.comments-header::before {
  content: '//';
  opacity: 0.5;
}
.giscus-setup-note {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent2);
  border-radius: var(--radius);
  padding: 16px 20px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.7;
}
.giscus-setup-note code {
  font-family: var(--font-mono);
  color: var(--accent);
  font-size: 0.8em;
}
.giscus-setup-note a {
  color: var(--accent);
  text-decoration: underline;
}

/* ── Friends Page ── */
.friends-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}

.friend-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  display: flex;
  align-items: flex-start;
  gap: 14px;
  transition: all var(--transition);
  text-decoration: none;
  color: inherit;
  position: relative;
  overflow: hidden;
}
.friend-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  transform: scaleX(0);
  transition: transform var(--transition);
}
.friend-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-3px);
  box-shadow: var(--shadow-card), var(--shadow-glow);
}
.friend-card:hover::before { transform: scaleX(1); }

.friend-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-dim), var(--accent2-dim));
  border: 2px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  flex-shrink: 0;
  overflow: hidden;
}
.friend-avatar img { width: 100%; height: 100%; object-fit: cover; }

.friend-info { flex: 1; min-width: 0; }
.friend-name {
  font-weight: 600;
  font-size: 0.95rem;
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.friend-name::after {
  content: '↗';
  font-size: 0.75rem;
  color: var(--text-muted);
  opacity: 0;
  transition: opacity var(--transition);
}
.friend-card:hover .friend-name::after { opacity: 1; }

.friend-url {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  color: var(--accent);
  margin-bottom: 6px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.friend-desc {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.friends-apply {
  margin-top: 48px;
  background: var(--bg-card);
  border: 1px dashed var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  text-align: center;
}
.friends-apply-title {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
}
.friends-apply-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 20px;
}

/* ── Guestbook ── */
.guestbook-wrap {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px 80px;
}

.guestbook-form-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  margin-bottom: 48px;
}
.guestbook-form-title {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--accent);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.guestbook-form-title::before {
  content: '';
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 6px var(--accent-glow);
}

.messages-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.message-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
  position: relative;
  transition: border-color var(--transition);
}
.message-card:hover { border-color: var(--border-hover); }

.message-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}
.message-avatar {
  width: 36px; height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-dim), var(--accent2-dim));
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  flex-shrink: 0;
}
.message-name {
  font-weight: 600;
  font-size: 0.875rem;
}
.message-date {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  margin-left: auto;
}
.message-body {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.7;
  white-space: pre-wrap;
  word-break: break-word;
}
.message-empty {
  text-align: center;
  padding: 60px 0;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

/* ── RSS Page ── */
.rss-wrap {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 24px 80px;
}
.rss-xml-block {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-secondary);
  overflow-x: auto;
  white-space: pre;
  max-height: 480px;
  overflow-y: auto;
  line-height: 1.6;
}
.rss-xml-block .xml-tag    { color: var(--accent); }
.rss-xml-block .xml-attr   { color: var(--accent2); }
.rss-xml-block .xml-value  { color: #10b981; }
.rss-xml-block .xml-text   { color: var(--text-primary); }

/* ── Admin: Friend Links panel ── */
.friend-admin-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 18px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition);
}
.friend-admin-item:hover { border-color: var(--border-hover); }
.friend-admin-info { flex: 1; min-width: 0; }
.friend-admin-name { font-weight: 600; font-size: 0.875rem; margin-bottom: 2px; }
.friend-admin-url  { font-size: 0.72rem; font-family: var(--font-mono); color: var(--accent); }

/* ── Admin: Multilingual binding ── */
.linked-posts-row {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 10px;
}
.linked-post-field { display: flex; flex-direction: column; gap: 4px; }
.linked-post-label {
  font-size: 0.68rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

/* ── Responsive ── */
@media (max-width: 900px) {
  .post-with-toc {
    grid-template-columns: 1fr;
    gap: 0;
  }
  .toc-sidebar { display: none; }
  .toc-mobile-toggle { display: flex; }
}

@media (max-width: 600px) {
  .friends-grid { grid-template-columns: 1fr; }
  .linked-posts-row { grid-template-columns: 1fr; }
}