/**
 * Scroll Spy Styles for Blog TOC
 */

/* ========================================
   TABLE OF CONTENTS
   ======================================== */

.blog-toc {
  position: sticky;
  top: 100px;
  max-height: calc(100vh - 120px);
  overflow-y: auto;
  padding: 24px;
  background: var(--color-bg-card, rgba(20, 21, 22, 0.8));
  border: 1px solid var(--color-border, rgba(146, 148, 159, 0.1));
  border-radius: 8px;
  margin-bottom: 32px;
  transition: all 0.3s ease;
}

.blog-toc__title {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-text-primary, #FFFCFA);
  margin: 0 0 16px 0;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-accent, #3076FE);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

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

.blog-toc__item {
  margin: 0;
  padding: 0;
}

/* Indent nested levels */
.blog-toc__item--level-2 {
  padding-left: 0;
}

.blog-toc__item--level-3 {
  padding-left: 16px;
}

.blog-toc__item--level-4 {
  padding-left: 32px;
}

.blog-toc__link {
  display: block;
  padding: 8px 12px;
  color: var(--color-text-secondary, rgba(255, 252, 250, 0.8));
  text-decoration: none;
  font-size: 14px;
  line-height: 1.5;
  border-left: 2px solid transparent;
  margin-left: -2px;
  transition: all 0.2s ease;
  position: relative;
}

.blog-toc__link::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 0;
  height: 2px;
  background: var(--color-accent, #3076FE);
  transition: width 0.3s ease;
}

.blog-toc__link:hover {
  color: var(--color-accent, #3076FE);
  padding-left: 16px;
}

.blog-toc__link:hover::before {
  width: 4px;
}

/* Active state */
.blog-toc__link.active {
  color: var(--color-accent, #3076FE);
  font-weight: 600;
  border-left-color: var(--color-accent, #3076FE);
  background: rgba(var(--color-accent-rgb, 48, 118, 254), 0.05);
  padding-left: 16px;
}

.blog-toc__item.active {
  position: relative;
}

/* Progress indicator */
.blog-toc::after {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  width: 3px;
  height: var(--scroll-progress, 0%);
  background: linear-gradient(to bottom, var(--color-accent, #3076FE), rgba(var(--color-accent-rgb, 48, 118, 254), 0.5));
  transition: height 0.3s ease;
  border-radius: 0 3px 3px 0;
}

/* Scrollbar styles */
.blog-toc::-webkit-scrollbar {
  width: 6px;
}

.blog-toc::-webkit-scrollbar-track {
  background: var(--color-bg-secondary, #141516);
  border-radius: 3px;
}

.blog-toc::-webkit-scrollbar-thumb {
  background: var(--color-border-strong, rgba(146, 148, 159, 0.2));
  border-radius: 3px;
}

.blog-toc::-webkit-scrollbar-thumb:hover {
  background: var(--color-accent, #3076FE);
}

/* ========================================
   RESPONSIVE LAYOUT
   ======================================== */

@media (min-width: 1200px) {
  /* Two-column layout: TOC sidebar + article */
  .blog-detail-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 40px;
    align-items: start;
  }

  .blog-toc {
    grid-column: 1;
    margin-bottom: 0;
  }

  article {
    grid-column: 2;
  }
}

@media (max-width: 1199px) {
  /* Mobile: TOC above article */
  .blog-toc {
    position: relative;
    top: auto;
    max-height: 300px;
    margin-bottom: 32px;
  }

  .blog-toc__title {
    cursor: pointer;
    position: relative;
    padding-right: 30px;
  }

  .blog-toc__title::after {
    content: '▼';
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    font-size: 12px;
    transition: transform 0.3s ease;
  }

  .blog-toc.collapsed .blog-toc__title::after {
    transform: translateY(-50%) rotate(-90deg);
  }

  .blog-toc.collapsed .blog-toc__list {
    display: none;
  }
}

@media (max-width: 768px) {
  .blog-toc {
    padding: 16px;
    margin-bottom: 24px;
  }

  .blog-toc__title {
    font-size: 14px;
    margin-bottom: 12px;
  }

  .blog-toc__link {
    font-size: 13px;
    padding: 6px 10px;
  }

  .blog-toc__link.active {
    padding-left: 14px;
  }
}

/* ========================================
   SMOOTH SCROLL INDICATOR
   ======================================== */

.scroll-progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--color-bg-secondary, #141516);
  z-index: 9999;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.scroll-progress-bar.visible {
  opacity: 1;
}

.scroll-progress-bar__fill {
  height: 100%;
  background: linear-gradient(to right, var(--color-accent, #3076FE), #AB47BC);
  width: 0%;
  transition: width 0.1s ease;
}

/* ========================================
   ACCESSIBILITY
   ======================================== */

.blog-toc__link:focus {
  outline: 2px solid var(--color-accent, #3076FE);
  outline-offset: 2px;
}

/* High contrast mode */
@media (prefers-contrast: high) {
  .blog-toc {
    border-width: 2px;
  }

  .blog-toc__link {
    border-left-width: 3px;
  }

  .blog-toc__link.active {
    border-left-width: 4px;
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .blog-toc,
  .blog-toc__link,
  .blog-toc__link::before,
  .scroll-progress-bar__fill {
    transition: none;
  }
}

/* Print */
@media print {
  .blog-toc {
    display: none;
  }
}