/* ═══════════════════════════════════════════════════
   ETHERLEARNING — Blog Styles
   ═══════════════════════════════════════════════════ */

/* ── Reading Progress Bar ────────────────────────── */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-soft));
  z-index: 1000;
  transition: width 0.1s linear;
}

/* ── Blog Hero ───────────────────────────────────── */
.blog-hero {
  padding: 64px 0 48px;
  text-align: center;
}

.blog-hero h1 {
  margin-bottom: 12px;
}

.blog-hero p {
  font-size: 1.05rem;
  color: var(--ink-soft);
  max-width: 480px;
  margin: 0 auto;
}

/* ── Category Filter Nav ─────────────────────────── */
.category-nav {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
  padding: 0 0 48px;
}

.cat-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 18px;
  border-radius: 999px;
  font-size: 0.88rem;
  font-weight: 500;
  border: 1.5px solid var(--paper-mid);
  background: var(--paper);
  color: var(--ink-soft);
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
}

.cat-pill:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-glow);
}

.cat-pill.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.cat-pill .cat-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: currentColor;
  opacity: 0.7;
}

/* ── Category Colors ─────────────────────────────── */
.cat--focus        { --cat-color: #3d4fd1; --cat-bg: rgba(61,79,209,0.10); }
.cat--memory       { --cat-color: #7c3aed; --cat-bg: rgba(124,58,237,0.10); }
.cat--psychology   { --cat-color: #0891b2; --cat-bg: rgba(8,145,178,0.10); }
.cat--dopamine     { --cat-color: #d97706; --cat-bg: rgba(217,119,6,0.10); }
.cat--productivity { --cat-color: #059669; --cat-bg: rgba(5,150,105,0.10); }

/* ── Featured Post ───────────────────────────────── */
.featured-post {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-xl);
  overflow: hidden;
  margin-bottom: 48px;
  transition: var(--transition);
  text-decoration: none;
  color: inherit;
}

.featured-post:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-3px);
  border-color: var(--accent);
}

.featured-cover {
  background: #1a1a2e;
  min-height: 320px;
  background-size: cover;
  background-position: center;
  position: relative;
  overflow: hidden;
}

.featured-body {
  padding: 40px 40px 40px 44px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 16px;
}

.featured-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
}

.featured-label::before {
  content: '';
  display: inline-block;
  width: 18px;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
}

.featured-body h2 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  line-height: 1.2;
  margin: 0;
  color: var(--ink);
}

.featured-body p {
  font-size: 0.97rem;
  color: var(--ink-soft);
  line-height: 1.65;
  margin: 0;
  max-width: 42ch;
}

.featured-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 0.82rem;
  color: var(--ink-faint);
  margin-top: 4px;
}

.featured-meta .read-more {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--accent);
  font-weight: 500;
  font-size: 0.88rem;
  transition: var(--transition);
}

.featured-meta .read-more:hover {
  gap: 10px;
}

/* ── Posts Grid ──────────────────────────────────── */
.posts-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 64px;
}

/* ── Post Card ───────────────────────────────────── */
.post-card {
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
  position: relative;
}

.post-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--accent);
}

.post-card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-soft));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s ease;
}

.post-card:hover::after {
  transform: scaleX(1);
}

.post-thumb {
  height: 140px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.8rem;
  background: var(--cat-bg, var(--accent-glow));
  position: relative;
  overflow: hidden;
}

.post-thumb::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at center, rgba(255,255,255,0.08) 0%, transparent 70%);
}

.post-content {
  padding: 22px 24px 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  flex: 1;
}

.post-category {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--cat-color, var(--accent));
  padding: 3px 10px;
  background: var(--cat-bg, var(--accent-glow));
  border-radius: 999px;
  align-self: flex-start;
}

.post-title {
  font-family: 'DM Serif Display', Georgia, serif;
  font-size: 1.12rem;
  line-height: 1.3;
  color: var(--ink);
  margin: 0;
}

.post-excerpt {
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.6;
  margin: 0;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.78rem;
  color: var(--ink-faint);
  margin-top: auto;
  padding-top: 8px;
  border-top: 1px solid var(--paper-mid);
}

.post-meta .dot {
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: var(--ink-faint);
}

/* ── Newsletter Strip ────────────────────────────── */
.blog-newsletter {
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-xl);
  padding: 48px;
  text-align: center;
  margin-bottom: 72px;
  position: relative;
  overflow: hidden;
}

.blog-newsletter::before {
  content: '';
  position: absolute;
  top: -80px;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 300px;
  background: radial-gradient(ellipse, var(--accent-glow) 0%, transparent 70%);
  pointer-events: none;
}

.blog-newsletter h2 {
  font-size: clamp(1.4rem, 3vw, 1.9rem);
  margin-bottom: 10px;
}

.blog-newsletter p {
  color: var(--ink-soft);
  font-size: 0.97rem;
  margin-bottom: 24px;
}

.newsletter-form {
  display: flex;
  gap: 10px;
  max-width: 440px;
  margin: 0 auto;
}

.newsletter-form input {
  flex: 1;
  padding: 11px 18px;
  border: 1.5px solid var(--paper-mid);
  border-radius: var(--radius-md);
  background: var(--paper);
  color: var(--ink);
  font-size: 0.92rem;
  font-family: inherit;
  transition: var(--transition);
  outline: none;
}

.newsletter-form input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.newsletter-form input::placeholder {
  color: var(--ink-faint);
}

/* ════════════════════════════════════════════════════
   ARTICLE PAGE
   ════════════════════════════════════════════════════ */

/* ── Article Header ──────────────────────────────── */
.article-header {
  max-width: 760px;
  margin: 0 auto;
  padding: 56px 24px 48px;
  text-align: center;
}

.article-category {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--cat-color, var(--accent));
  padding: 4px 14px;
  background: var(--cat-bg, var(--accent-glow));
  border-radius: 999px;
  margin-bottom: 20px;
}

.article-header h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4.5vw, 3rem);
  font-weight: 400;
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -0.025em;
}

.article-subtitle {
  font-family: var(--font-body);
  font-size: 1.12rem;
  font-weight: 400;
  color: var(--ink-soft);
  line-height: 1.65;
  margin-bottom: 28px;
  max-width: 56ch;
  margin-left: auto;
  margin-right: auto;
}

.article-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  font-size: 0.85rem;
  color: var(--ink-faint);
  flex-wrap: wrap;
}

.article-meta .meta-divider {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--paper-mid);
}

/* ── Article Cover ───────────────────────────────── */
.article-cover {
  max-width: 880px;
  margin: 0 auto 56px;
  padding: 0 24px;
}

.article-cover-inner {
  height: 360px;
  border-radius: var(--radius-xl);
  background: linear-gradient(135deg, #3d4fd1 0%, #6875e8 50%, #9b5cf6 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 7rem;
  position: relative;
  overflow: hidden;
}

.article-cover-inner::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 30% 40%, rgba(255,255,255,0.18) 0%, transparent 60%);
}

/* ── Article + TOC two-column layout ─────────────── */
.article-layout {
  display: grid;
  grid-template-columns: 1fr 240px;
  column-gap: 0;
  max-width: 1020px;
  margin: 0 auto;
  align-items: start;
  padding: 0 24px;
}

/* ── TOC Sidebar ─────────────────────────────────── */
.toc-sidebar {
  order: 2;
  position: sticky;
  top: 88px;
  padding: 0 0 72px 32px;
}

.toc-inner {
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-lg);
  padding: 20px 20px 16px;
}

.toc-heading {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin: 0 0 14px;
  max-width: none;
}

.toc-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.toc-item {}

.toc-link {
  display: block;
  font-size: 0.84rem;
  line-height: 1.45;
  color: var(--ink-soft);
  padding: 5px 8px;
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
  text-decoration: none;
  transition: color var(--transition), background var(--transition), border-color var(--transition);
}

.toc-link:hover {
  color: var(--accent);
  background: var(--accent-glow);
}

.toc-link.active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: var(--accent-glow);
  font-weight: 500;
}

/* TOC number prefix */
.toc-num {
  font-size: 0.72rem;
  color: var(--ink-faint);
  font-weight: 500;
  letter-spacing: 0.03em;
  margin-right: 6px;
  flex-shrink: 0;
  font-variant-numeric: tabular-nums;
}

.toc-link.active .toc-num {
  color: var(--accent);
}

/* TOC h2 row with toggle */
.toc-item--parent {
  display: flex;
  flex-direction: column;
}

.toc-item-row {
  display: flex;
  align-items: center;
  gap: 2px;
}

.toc-item-row .toc-link {
  flex: 1;
}

.toc-toggle {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--ink-faint);
  border-radius: var(--radius-sm);
  transition: color var(--transition), transform var(--transition), background var(--transition);
  padding: 0;
  font-size: 0.6rem;
}

.toc-toggle:hover {
  color: var(--accent);
  background: var(--accent-glow);
}

.toc-toggle.open {
  transform: rotate(90deg);
}

/* TOC h3 sub-list */
.toc-sub-list {
  list-style: none;
  margin: 2px 0 4px;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1px;
  overflow: hidden;
  max-height: 0;
  transition: max-height 280ms cubic-bezier(0.4, 0, 0.2, 1),
              opacity   200ms ease;
  opacity: 0;
}

.toc-sub-list.open {
  max-height: 600px;
  opacity: 1;
}

.toc-item--sub .toc-link {
  padding-left: 18px;
  font-size: 0.80rem;
  color: var(--ink-faint);
}

/* ── Article Body ────────────────────────────────── */
.article-body {
  order: 1;
  max-width: 700px;
  width: 100%;
  padding: 0 0 72px 3rem;       /* left gutter for aside numbers */
  counter-reset: h2-counter;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

.article-body p {
  font-family: var(--font-body);
  font-size: 1.06rem;
  line-height: 1.82;
  color: var(--ink-soft);
  margin-bottom: 26px;
  font-weight: 400;
}

/* Drop cap on first paragraph */
.article-body > p:first-of-type {
  color: var(--ink);
}

.article-body > p:first-of-type::first-letter {
  font-family: var(--font-display);
  float: left;
  font-size: 3.8rem;
  line-height: 0.85;
  margin-right: 10px;
  margin-top: 6px;
  color: var(--accent);
}

.article-body h2 {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 2.8vw, 1.7rem);
  font-weight: 400;
  letter-spacing: -0.02em;
  margin-top: 52px;
  margin-bottom: 14px;
  color: var(--ink);
  line-height: 1.25;
  counter-increment: h2-counter;
  counter-reset: h3-counter;
  position: relative;
}

.article-body h2::before {
  content: counter(h2-counter) ".";
  position: absolute;
  left: -2.6rem;
  top: 0.28em;
  font-family: var(--font-body);
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--ink-faint);
  letter-spacing: 0.04em;
  line-height: 1;
}

.article-body h3 {
  font-family: var(--font-body);
  font-size: 1.08rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-top: 32px;
  margin-bottom: 10px;
  color: var(--ink);
  line-height: 1.35;
  counter-increment: h3-counter;
  position: relative;
}

.article-body h3::before {
  content: counter(h2-counter) "." counter(h3-counter);
  position: absolute;
  left: -2.6rem;
  top: 0.22em;
  font-family: var(--font-body);
  font-size: 0.68rem;
  font-weight: 500;
  color: var(--ink-faint);
  letter-spacing: 0.03em;
  line-height: 1;
}

.article-body ul,
.article-body ol {
  padding-left: 26px;
  margin-bottom: 26px;
}

.article-body li {
  font-family: var(--font-body);
  font-size: 1.06rem;
  line-height: 1.75;
  color: var(--ink-soft);
  margin-bottom: 8px;
}

.article-body strong {
  color: var(--ink);
  font-weight: 600;
}

.article-body em {
  font-style: italic;
  color: var(--ink);
}

.article-body a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

/* ── Pull Quote ──────────────────────────────────── */
.pull-quote {
  margin: 44px 0;
  padding: 28px 32px;
  border-left: 4px solid var(--accent);
  background: var(--accent-glow);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.pull-quote p {
  font-family: var(--font-display) !important;
  font-size: 1.22rem !important;
  line-height: 1.6 !important;
  color: var(--ink) !important;
  margin: 0 !important;
  font-style: italic;
  font-weight: 400;
}

/* ── Callout Box ─────────────────────────────────── */
.callout {
  margin: 32px 0;
  padding: 20px 24px;
  border-radius: var(--radius-md);
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.callout p {
  font-size: 0.97rem !important;
  line-height: 1.7 !important;
  margin-bottom: 0 !important;
}

.callout-icon {
  font-size: 1.3rem;
  flex-shrink: 0;
  margin-top: 1px;
}

.callout p {
  margin: 0 !important;
  font-size: 0.95rem !important;
}

/* ── Article Share ───────────────────────────────── */
.article-share {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 48px 0 40px;
  padding-top: 32px;
  border-top: 1px solid var(--paper-mid);
  flex-wrap: wrap;
}

.article-share span {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--ink-faint);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  font-weight: 500;
  border: 1.5px solid var(--paper-mid);
  background: var(--paper);
  color: var(--ink-soft);
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
}

.share-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* ── FAQ Section ─────────────────────────────────── */
.faq-section {
  margin: 8px 0 32px;
}

.faq-item {
  border-top: 1px solid var(--paper-mid);
  padding: 24px 0;
}

.faq-item:last-child {
  border-bottom: 1px solid var(--paper-mid);
}

.faq-item h3 {
  font-family: var(--font-body);
  font-size: 1.04rem;
  font-weight: 600;
  margin-top: 0;
  margin-bottom: 10px;
  color: var(--ink);
  letter-spacing: -0.01em;
}

.faq-item p {
  font-size: 0.98rem;
  line-height: 1.75;
  color: var(--ink-soft);
  margin-bottom: 0;
}

/* ── Author Bio ──────────────────────────────────── */
.author-bio {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  padding: 28px;
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-lg);
  margin-bottom: 56px;
}

.author-avatar {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-soft));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  flex-shrink: 0;
}

.author-info h4 {
  font-size: 0.97rem;
  margin-bottom: 4px;
  color: var(--ink);
}

.author-info p {
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.6;
  margin: 0;
}

/* ── Related Posts ───────────────────────────────── */
.related-posts {
  border-top: 1px solid var(--paper-mid);
  padding-top: 48px;
  margin-bottom: 72px;
}

.related-posts h2 {
  font-size: 1.3rem;
  margin-bottom: 24px;
  color: var(--ink);
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.related-card {
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-md);
  padding: 20px;
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

.related-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.related-card .post-category {
  margin-bottom: 10px;
}

.related-card h4 {
  font-size: 0.95rem;
  line-height: 1.4;
  color: var(--ink);
  margin: 0;
}

/* ════════════════════════════════════════════════════
   RESPONSIVE
   ════════════════════════════════════════════════════ */

@media (max-width: 980px) {
  .article-layout {
    grid-template-columns: 1fr;
    padding: 0;
  }
  .toc-sidebar {
    order: -1;
    position: static;
    padding: 0 24px 8px;
  }
  .toc-inner {
    border-radius: var(--radius-md);
  }
  .article-body {
    padding: 0 24px 72px;   /* no left gutter on mobile */
  }
  /* switch aside numbers to inline on mobile */
  .article-body h2::before,
  .article-body h3::before {
    position: static;
    display: inline;
    margin-right: 0.35em;
    top: auto;
    left: auto;
  }
}

@media (max-width: 900px) {
  .featured-post {
    grid-template-columns: 1fr;
  }

  .featured-cover {
    min-height: 200px;
    font-size: 4rem;
  }

  .featured-body {
    padding: 28px;
  }

  .posts-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .related-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .posts-grid {
    grid-template-columns: 1fr;
  }

  .blog-newsletter {
    padding: 32px 20px;
  }

  .newsletter-form {
    flex-direction: column;
  }

  .article-header {
    padding: 40px 20px 32px;
  }

  .article-cover-inner {
    height: 220px;
    font-size: 4rem;
  }

  .article-body p:first-of-type::first-letter {
    font-size: 3rem;
  }

  .pull-quote {
    padding: 20px;
  }

  .pull-quote p {
    font-size: 1.08rem !important;
  }

  .related-grid {
    grid-template-columns: 1fr;
  }

  .author-bio {
    flex-direction: column;
    gap: 14px;
  }
}