/* ═══════════════════════════════════════════════════════════════════
   blog-interactive.css — ChordStar Blog Interactive Enhancements
   Features: Search, Bookmarks, TOC, Back-to-Top, Card Animations,
             Related Articles, Reading Stats
═══════════════════════════════════════════════════════════════════ */

/* ── Mobile: Filter bar — sticky, clean, horizontal scroll ── */
@media (max-width: 600px) {
  #tkModal-blog .filter-bar {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(7, 6, 15, 0.97);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.07);
    margin-top: 52px;
    /* No overflow here — prevents vertical clipping */
    overflow: visible;
    flex-wrap: nowrap;
    display: block;
    padding: 10px 0;
  }

  /* Inner wrapper handles horizontal scroll only */
  #tkModal-blog .filter-scroll-inner {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 8px;
    overflow-x: auto;
    overflow-y: visible;
    padding: 4px 16px 4px;
    scrollbar-width: none;
    -webkit-overflow-scrolling: touch;
  }
  #tkModal-blog .filter-scroll-inner::-webkit-scrollbar { display: none; }

  #tkModal-blog .filter-btn {
    flex-shrink: 0;
    white-space: nowrap;
    padding: 8px 16px;
    font-size: 0.75rem;
    line-height: 1.4;
  }
  #tkModal-blog .blog-intro { padding-top: 16px; }
}

/* ── Bookmark Button on Cards ── */
#tkModal-blog .card-bookmark-btn {
  position: absolute;
  top: 10px;
  right: 10px;
  background: rgba(7,6,15,0.75);
  border: 1px solid var(--blog-border);
  border-radius: 50%;
  width: 32px; height: 32px;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  opacity: 0;
  transition: opacity 0.18s, background 0.18s, border-color 0.18s, transform 0.15s;
  z-index: 2;
  color: var(--blog-dim);
  backdrop-filter: blur(4px);
}
#tkModal-blog .blog-card:hover .card-bookmark-btn,
#tkModal-blog .card-bookmark-btn.is-bookmarked {
  opacity: 1;
}
#tkModal-blog .card-bookmark-btn.is-bookmarked {
  background: rgba(192,132,252,0.2);
  border-color: var(--blog-accent);
  color: var(--blog-accent);
}
#tkModal-blog .card-bookmark-btn:hover {
  transform: scale(1.12);
  background: rgba(192,132,252,0.15);
}
#tkModal-blog .card-thumb { position: relative; }

/* Bookmarks filter tab */
#tkModal-blog .filter-btn[data-filter="bookmarks"] {
  border: 1px dashed var(--blog-border-md);
}
#tkModal-blog .filter-btn[data-filter="bookmarks"].active {
  border-style: solid;
}

/* ── Card Entrance Animation ── */
#tkModal-blog .blog-card {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.42s ease, transform 0.42s ease;
}
#tkModal-blog .blog-card.card-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Table of Contents (TOC) ── */
#tkModal-blog .article-toc {
  background: var(--blog-surface);
  border: 1px solid var(--blog-border-md);
  border-radius: var(--blog-r);
  padding: 16px 20px;
  margin: 24px 0;
  font-family: var(--font-body);
}
#tkModal-blog .article-toc-title {
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--blog-accent);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  user-select: none;
}
#tkModal-blog .toc-toggle-icon {
  margin-left: auto;
  transition: transform 0.2s;
  font-style: normal;
}
#tkModal-blog .article-toc.collapsed .toc-toggle-icon {
  transform: rotate(-90deg);
}
#tkModal-blog .article-toc-list {
  list-style: none;
  border-top: 1px solid var(--blog-border);
  padding-top: 10px;
  overflow: hidden;
  transition: max-height 0.3s ease;
  max-height: 500px;
}
#tkModal-blog .article-toc.collapsed .article-toc-list {
  max-height: 0;
  padding-top: 0;
  border-top: none;
}
#tkModal-blog .article-toc-list li {
  margin: 4px 0;
}
#tkModal-blog .article-toc-list a {
  color: var(--blog-dim);
  text-decoration: none;
  font-size: var(--text-sm);
  line-height: 1.5;
  display: block;
  padding: 3px 0 3px 12px;
  border-left: 2px solid transparent;
  transition: color 0.15s, border-color 0.15s, padding-left 0.15s;
  border-radius: 0 4px 4px 0;
}
#tkModal-blog .article-toc-list a:hover,
#tkModal-blog .article-toc-list a.toc-active {
  color: var(--blog-text);
  border-left-color: var(--blog-accent);
  padding-left: 16px;
}
#tkModal-blog .article-toc-list .toc-h3 > a {
  padding-left: 24px;
  font-size: 0.75rem;
}
#tkModal-blog .article-toc-list .toc-h3 > a:hover,
#tkModal-blog .article-toc-list .toc-h3 > a.toc-active {
  padding-left: 28px;
}

/* ── Back to Top button ── */
#tkModal-blog .art-back-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  background: var(--blog-accent);
  color: #07060f;
  border: none;
  border-radius: 50%;
  width: 42px; height: 42px;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.25s, transform 0.25s;
  z-index: 9999;
  box-shadow: 0 4px 20px rgba(192,132,252,0.4);
}
#tkModal-blog .art-back-top.visible {
  opacity: 1;
  transform: translateY(0);
}
#tkModal-blog .art-back-top:hover {
  background: #d4a7fd;
  transform: translateY(-2px);
}

/* ── Related Articles ── */
#tkModal-blog .related-articles {
  margin-top: 40px;
  border-top: 1px solid var(--blog-border-md);
  padding-top: 28px;
}
#tkModal-blog .related-articles-title {
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--blog-dim);
  margin-bottom: 16px;
}
#tkModal-blog .related-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 12px;
}
#tkModal-blog .related-card {
  background: var(--blog-surface);
  border: 1px solid var(--blog-border);
  border-radius: var(--blog-r);
  padding: 14px 16px;
  cursor: pointer;
  transition: border-color 0.18s, background 0.18s, transform 0.15s;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
#tkModal-blog .related-card:hover {
  border-color: var(--blog-accent);
  background: var(--blog-accent-lo);
  transform: translateY(-2px);
}
#tkModal-blog .related-card-tag {
  font-size: var(--text-xs);
  color: var(--blog-accent);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
#tkModal-blog .related-card-title {
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--blog-text);
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
#tkModal-blog .related-card-meta {
  font-size: var(--text-xs);
  color: var(--blog-dim);
}

/* ── Reading Stats chip ── */
#tkModal-blog .art-reading-stats {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: var(--text-xs);
  color: var(--blog-dim);
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--blog-border);
  border-radius: var(--blog-r-pill);
  padding: 4px 12px;
  margin-top: 8px;
  font-family: var(--font-body);
}
#tkModal-blog .art-reading-stats span { color: var(--blog-text); }

/* ── Bookmark toast ── */
#blog-bm-toast {
  position: fixed;
  bottom: 88px;
  right: 24px;
  background: var(--blog-surface, #0e0c1c);
  border: 1px solid var(--blog-border-md, rgba(255,255,255,0.1));
  border-radius: 10px;
  padding: 10px 18px;
  font-family: 'DM Sans', sans-serif;
  font-size: 0.82rem;
  color: #ede9f6;
  box-shadow: 0 8px 32px rgba(0,0,0,0.5);
  z-index: 99999;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.2s, transform 0.2s;
  pointer-events: none;
}
#blog-bm-toast.show {
  opacity: 1;
  transform: translateY(0);
}