/* Articles / Research Intelligence Series — extends styles.css */

/* ─── Header ─────────────────────────────────────────────────────── */
.ar-header {
  padding: 160px 0 80px;
  position: relative;
  background: var(--bg);
  overflow: hidden;
}
.ar-header::before {
  content: '';
  position: absolute;
  top: -200px; left: -200px;
  width: 600px; height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-light) 0%, transparent 65%);
  opacity: 0.32;
  filter: blur(50px);
  pointer-events: none;
}
.ar-header > .container { position: relative; z-index: 1; }

/* reuse .pp-crumbs */
.pp-crumbs {
  display: flex; gap: 12px; align-items: center;
  font-family: 'JetBrains Mono', 'Anuphan', monospace;
  font-size: 11px; letter-spacing: 0.15em;
  color: var(--fg-mute);
  text-transform: uppercase;
  margin-bottom: 56px;
}
.pp-crumbs a {
  color: var(--fg-mute); text-decoration: none; transition: color 0.2s;
}
.pp-crumbs a:hover { color: var(--accent); }
.pp-crumbs a.cur { color: var(--fg); }
.pp-crumbs .sep { opacity: 0.4; }

.ar-header-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 80px;
  align-items: end;
  margin-bottom: 80px;
}
.ar-title {
  font-size: clamp(56px, 7vw, 104px);
  letter-spacing: -0.03em;
  line-height: 0.98;
  margin-top: 24px;
}
.ar-title .accent { color: var(--accent); }
.ar-header-aside {
  padding-bottom: 12px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}
.ar-lead {
  font-size: 17px;
  line-height: 1.65;
  color: var(--fg-dim);
  padding-left: 24px;
  border-left: 1px solid var(--line-strong);
}
.ar-jump {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  align-self: flex-start;
  margin-left: 24px;
  text-decoration: none;
  color: var(--navy);
  padding: 10px 18px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  white-space: nowrap;
  transition: all 0.2s;
}
.ar-jump:hover {
  border-color: var(--navy);
  background: var(--navy);
  color: #fff;
}
.ar-jump .mono { font-size: 11px; letter-spacing: 0.16em; }

.ar-header-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  border-top: 1px solid var(--line-strong);
  border-bottom: 1px solid var(--line-strong);
}
.ar-hs {
  padding: 28px 32px 28px 0;
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.ar-hs:last-child { border-right: none; }
.ar-hs .v {
  font-size: 56px;
  font-weight: 500;
  color: var(--navy);
  letter-spacing: -0.02em;
  line-height: 1;
  display: flex; align-items: baseline; gap: 6px;
}
.ar-hs .v .u {
  font-size: 14px;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.05em;
}
.ar-hs .k {
  font-size: 13px;
  color: var(--fg-dim);
}

/* ─── Featured ───────────────────────────────────────────────────── */
.ar-featured {
  padding: 96px 0 96px;
  background: var(--bg);
  border-top: 1px solid var(--line);
  position: relative;
}
.ar-featured-grid {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 80px;
  align-items: start;
}
.ar-featured-cover {
  position: relative;
  aspect-ratio: 5 / 6;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 28px 60px rgba(14, 31, 68, 0.18);
  position: sticky;
  top: 100px;
}
.cover-svg { width: 100%; height: 100%; display: block; }
.ar-photo { background: var(--bg-card); overflow: hidden; display: block; }
.ar-photo img { width: 100%; height: 100%; object-fit: cover; display: block; }
.ar-featured-cover.ar-photo { text-decoration: none; }
.ar-featured-cover.ar-photo:hover img { transform: scale(1.03); }
.ar-featured-cover.ar-photo img { transition: transform 0.5s cubic-bezier(0.2,0.7,0.2,1); }
.ar-featured-badge {
  position: absolute;
  top: 16px; right: 16px;
  background: rgba(255,255,255,0.95);
  color: var(--navy);
  padding: 8px 14px;
  border-radius: 999px;
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  display: inline-flex; align-items: center; gap: 8px;
  z-index: 2;
}
.ar-featured-badge .dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.4); }
}
.ar-featured-corner {
  position: absolute;
  width: 18px; height: 18px;
  border: 1.5px solid var(--accent-light);
  z-index: 2;
}
.ar-featured-corner.tl { top: 10px; left: 10px; border-right: none; border-bottom: none; }
.ar-featured-corner.tr { top: 10px; right: 10px; border-left: none; border-bottom: none; }
.ar-featured-corner.bl { bottom: 10px; left: 10px; border-right: none; border-top: none; }
.ar-featured-corner.br { bottom: 10px; right: 10px; border-left: none; border-top: none; }

.ar-featured-text { padding-top: 8px; }
.ar-cat {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  margin-bottom: 20px;
}
.ar-cat .pip {
  width: 8px; height: 8px;
  border-radius: 50%;
}
.ar-featured-title {
  font-size: clamp(36px, 4.2vw, 56px);
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--navy);
  margin-bottom: 24px;
}
.ar-featured-excerpt {
  font-size: 18px;
  line-height: 1.65;
  color: var(--fg-dim);
  margin-bottom: 32px;
  max-width: 640px;
}

.ar-abstract-points {
  list-style: none;
  padding: 0;
  margin: 0 0 36px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--bg-card);
}
.ar-abstract-points li {
  display: flex;
  gap: 18px;
  padding: 18px 20px;
  border-bottom: 1px dashed var(--line);
  font-size: 15px;
  line-height: 1.55;
  color: var(--fg);
}
.ar-abstract-points li:last-child { border-bottom: none; }
.ar-abstract-points .mark {
  color: var(--accent);
  font-size: 11px;
  letter-spacing: 0.12em;
  flex-shrink: 0;
  padding-top: 3px;
}

.ar-featured-meta {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 24px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}
.ar-authors {
  display: flex;
  gap: 16px;
}
.ar-author {
  display: flex;
  gap: 12px;
  align-items: center;
}
.ar-avatar {
  width: 42px; height: 42px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  color: #fff;
  font-family: 'JetBrains Mono', 'Anuphan', monospace;
  font-size: 14px;
  font-weight: 700;
  flex-shrink: 0;
}
.ar-author .info { display: flex; flex-direction: column; gap: 2px; }
.ar-author .n { font-size: 13px; font-weight: 600; color: var(--navy); }
.ar-author .r { font-size: 10px; letter-spacing: 0.12em; color: var(--fg-mute); text-transform: uppercase; }

.ar-meta-cols {
  display: flex;
  gap: 28px;
}
.ar-meta-col { display: flex; flex-direction: column; gap: 4px; }
.ar-meta-col .k { font-size: 10px; letter-spacing: 0.18em; color: var(--fg-mute); text-transform: uppercase; }
.ar-meta-col .v { font-size: 14px; font-weight: 500; color: var(--navy); }

.ar-featured-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}
.btn-ghost-dark {
  background: transparent;
  color: var(--navy);
  border: 1px solid var(--line-strong);
  padding: 12px 20px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 600;
  display: inline-flex; align-items: center; gap: 8px;
  text-decoration: none;
  transition: all 0.2s;
}
.btn-ghost-dark:hover {
  border-color: var(--navy);
  background: var(--navy);
  color: #fff;
}

.ar-featured-tags {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}
.ar-tag {
  font-family: 'JetBrains Mono', 'Anuphan', monospace;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--accent);
  background: rgba(240, 129, 36, 0.08);
  padding: 5px 12px;
  border-radius: 999px;
}

/* ─── Filter bar ─────────────────────────────────────────────────── */
.ar-filterbar {
  position: sticky;
  top: 72px;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  backdrop-filter: blur(20px) saturate(140%);
  -webkit-backdrop-filter: blur(20px) saturate(140%);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.ar-filter-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  padding: 16px 0;
}
.ar-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}
.ar-tab {
  padding: 10px 18px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  background: transparent;
  color: var(--fg);
  font-family: inherit;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  letter-spacing: 0.03em;
  transition: all 0.2s ease;
}
.ar-tab:hover { border-color: var(--accent); color: var(--accent); }
.ar-tab.on { color: #fff; }

.ar-meta-line {
  display: flex;
  align-items: center;
  gap: 14px;
  white-space: nowrap;
  color: var(--fg-mute);
}
.ar-divider {
  width: 1px; height: 12px; background: var(--line-strong);
}

/* ─── Article grid ───────────────────────────────────────────────── */
.ar-grid-section {
  padding: 64px 0 96px;
  background: var(--bg);
}
.ar-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 32px;
}
.ar-empty {
  padding: 80px 0;
  text-align: center;
  color: var(--fg-dim);
  font-size: 16px;
  border: 1px dashed var(--line-strong);
  border-radius: 12px;
}

.ar-card-link { text-decoration: none; color: inherit; display: flex; height: 100%; }
.ar-card {
  background: var(--bg-alt);
  border-radius: 16px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  width: 100%;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  border: 1px solid var(--line);
  cursor: pointer;
}
.ar-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 24px 48px rgba(14, 31, 68, 0.1);
}
.ar-card:hover .ar-card-arrow {
  color: var(--accent);
  transform: translateX(4px);
}
.ar-card-cover {
  aspect-ratio: 5 / 3;
  position: relative;
  overflow: hidden;
}
.ar-card:hover .ar-card-cover img { transform: scale(1.04); }
.ar-card-cover img { transition: transform 0.5s cubic-bezier(0.2,0.7,0.2,1); }
.ar-card-issue {
  position: absolute;
  top: 14px; right: 14px;
  background: rgba(255,255,255,0.94);
  color: var(--navy);
  padding: 5px 10px;
  border-radius: 6px;
  font-size: 10px;
  letter-spacing: 0.16em;
}
.ar-card-body {
  padding: 20px 22px 16px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.ar-card-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}
.ar-card-cat {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 10px; letter-spacing: 0.18em;
}
.ar-card-cat .pip {
  width: 6px; height: 6px; border-radius: 50%;
}
.ar-card-read {
  display: inline-flex; align-items: center; gap: 4px;
  font-size: 10px; letter-spacing: 0.1em;
  color: var(--fg-mute);
}
.ar-card-title {
  font-size: 19px;
  font-weight: 500;
  color: var(--navy);
  letter-spacing: -0.01em;
  line-height: 1.3;
  text-wrap: pretty;
  min-height: 2.6em;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.ar-card-excerpt {
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--fg-dim);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.ar-card-tags {
  display: flex; gap: 6px; flex-wrap: wrap; margin-top: auto;
  padding-top: 6px;
}
.ar-tag-sm {
  font-family: 'JetBrains Mono', 'Anuphan', monospace;
  font-size: 9.5px;
  letter-spacing: 0.06em;
  color: var(--fg-mute);
  background: var(--bg-card);
  padding: 3px 8px;
  border-radius: 999px;
}
.ar-card-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 22px;
  border-top: 1px dashed var(--line);
  margin-top: auto;
}
.ar-card-by { display: flex; flex-direction: column; gap: 2px; }
.ar-card-date {
  font-size: 10px; letter-spacing: 0.14em; color: var(--fg-mute); text-transform: uppercase;
}
.ar-card-author {
  font-size: 12px; color: var(--navy); font-weight: 500;
}
.ar-card-arrow {
  color: var(--fg-mute);
  transition: all 0.25s ease;
}

/* ─── Topics cloud ───────────────────────────────────────────────── */
.ar-topics {
  padding: 120px 0;
  background: var(--bg);
  border-top: 1px solid var(--line);
}
.ar-topics-grid {
  display: grid;
  grid-template-columns: 0.8fr 1.5fr;
  gap: 80px;
  align-items: start;
}
.ar-topics-title {
  font-size: clamp(40px, 4.4vw, 64px);
  margin-top: 20px;
  letter-spacing: -0.02em;
  line-height: 1.05;
  color: var(--navy);
}
.ital-style { color: var(--accent); }
.ar-topics-lead {
  margin-top: 20px;
  font-size: 16px;
  line-height: 1.65;
  color: var(--fg-dim);
  max-width: 360px;
}
.ar-topic-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.ar-topic-chip {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 18px;
  background: var(--bg-alt);
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--navy);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: all 0.2s ease;
}
.ar-topic-chip:hover {
  background: var(--navy);
  color: #fff;
  border-color: var(--navy);
  transform: translateY(-2px);
}
.ar-topic-chip:hover .ar-topic-count {
  color: var(--accent-light);
  background: rgba(255,255,255,0.1);
}
.ar-topic-count {
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--fg-mute);
  background: var(--bg-card);
  padding: 3px 8px;
  border-radius: 6px;
  transition: all 0.2s;
}

/* ─── Subscribe ──────────────────────────────────────────────────── */
.ar-subscribe {
  padding: 120px 0;
  background: var(--navy);
  color: var(--fg-on-navy);
  position: relative;
  overflow: hidden;
}
.ar-subscribe::before {
  content: '';
  position: absolute;
  top: -200px; right: -160px;
  width: 540px; height: 540px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-light) 0%, transparent 65%);
  opacity: 0.22;
  filter: blur(60px);
}
.ar-subscribe::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image: linear-gradient(to right, rgba(255,255,255,0.04) 1px, transparent 1px);
  background-size: 80px 80px;
  pointer-events: none;
}
.ar-subscribe .container { position: relative; z-index: 1; }
.ar-sub-grid {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 80px;
  align-items: center;
}
.ar-sub-title {
  font-size: clamp(40px, 4.6vw, 64px);
  margin-top: 20px;
  letter-spacing: -0.02em;
  line-height: 1.05;
}
.ar-sub-title .accent { color: var(--accent-light); }
.ar-sub-lead {
  margin-top: 24px;
  font-size: 16px;
  line-height: 1.65;
  color: var(--fg-on-navy-dim);
  max-width: 440px;
}
.ar-sub-channels {
  display: flex;
  flex-direction: column;
  gap: 0;
  border-top: 1px solid var(--line-navy);
}
.ar-sub-channel {
  display: grid;
  grid-template-columns: 160px 1fr auto;
  align-items: center;
  gap: 16px;
  padding: 22px 6px;
  border-bottom: 1px solid var(--line-navy);
  text-decoration: none;
  transition: padding 0.2s, background 0.2s;
}
.ar-sub-channel:hover { padding-left: 18px; }
.ar-sub-channel .k {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--accent-light);
}
.ar-sub-channel .v {
  font-size: 20px;
  font-weight: 500;
  color: var(--fg-on-navy);
  letter-spacing: -0.005em;
}
.ar-sub-arrow {
  width: 36px; height: 36px;
  border-radius: 50%;
  border: 1px solid var(--line-navy);
  display: inline-flex; align-items: center; justify-content: center;
  color: var(--fg-on-navy-dim);
  transition: all 0.2s;
}
.ar-sub-channel:hover .ar-sub-arrow {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.ar-sub-form {
  display: flex;
  flex-direction: column;
  gap: 24px;
}
.ar-sub-row {
  display: flex;
  gap: 10px;
  padding: 8px;
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--line-navy);
  border-radius: 999px;
}
.ar-sub-input {
  flex: 1;
  background: transparent;
  border: none;
  padding: 12px 18px;
  color: var(--fg-on-navy);
  font-family: inherit;
  font-size: 15px;
  outline: none;
}
.ar-sub-input::placeholder { color: var(--fg-on-navy-dim); }
.ar-sub-checks {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.ar-check {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 14px;
  color: var(--fg-on-navy-dim);
  cursor: pointer;
}
.ar-check input {
  appearance: none;
  width: 16px; height: 16px;
  border: 1px solid var(--line-navy);
  border-radius: 4px;
  background: rgba(255,255,255,0.06);
  cursor: pointer;
  position: relative;
  flex-shrink: 0;
}
.ar-check input:checked {
  background: var(--accent);
  border-color: var(--accent);
}
.ar-check input:checked::after {
  content: '';
  position: absolute;
  top: 2px; left: 5px;
  width: 4px; height: 8px;
  border: solid #fff;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}
.ar-check:hover span { color: var(--fg-on-navy); }

/* ─── Footer overrides ───────────────────────────────────────────── */
.ar-footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 56px;
  padding: 80px 0 40px;
}

/* btn reuse (defined in products.css too) */
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 12px 22px;
  border-radius: 999px;
  font-family: inherit;
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: none;
  transition: all 0.2s ease;
}
.btn-orange {
  background: var(--accent);
  color: #fff;
}
.btn-orange:hover { background: var(--accent-deep); }

/* Active nav link reuse */
.nav-link.active { color: var(--accent); position: relative; }
.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -6px; left: 0; right: 0;
  height: 2px;
  background: var(--accent);
}

/* ─── Responsive ─────────────────────────────────────────────────── */
@media (max-width: 980px) {
  .ar-header-grid { grid-template-columns: 1fr; gap: 32px; }
  .ar-lead { padding-left: 0; border-left: none; padding-top: 16px; border-top: 1px solid var(--line); }
  .ar-jump { margin-left: 0; }
  .ar-header-stats { grid-template-columns: repeat(2, 1fr); }
  .ar-hs:nth-child(1), .ar-hs:nth-child(2) { border-bottom: 1px solid var(--line); }
  .ar-hs:nth-child(2) { border-right: none; }
  .ar-featured-grid { grid-template-columns: 1fr; gap: 40px; }
  .ar-featured-cover { position: static; max-width: 360px; }
  .ar-sub-channel { grid-template-columns: 110px 1fr auto; gap: 10px; }
  .ar-topics-grid { grid-template-columns: 1fr; gap: 32px; }
  .ar-sub-grid { grid-template-columns: 1fr; gap: 32px; }
  .ar-footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .ar-filter-inner { flex-direction: column; align-items: stretch; }
  .ar-meta-line { justify-content: center; }
}