:root {
  --bg-deep: #0a0e1a;
  --bg-surface: #111728;
  --bg-elevated: #161d33;
  --bg-elevated-2: #1a2342;

  --accent: #4f7df5;
  --accent-2: #22d3a7;
  --accent-glow: rgba(79, 125, 245, 0.35);

  --text-primary: #e8ecf4;
  --text-secondary: #8a93ad;
  --text-dim: #5b6480;

  --border: rgba(140, 160, 220, 0.10);
  --border-strong: rgba(140, 160, 220, 0.18);

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;

  --shadow-lg: 0 24px 60px rgba(0,0,0,0.5);
  --shadow-glow: 0 0 0 1px rgba(79,125,245,0.35), 0 8px 28px rgba(79,125,245,0.25);

  --status-stable: #22d3a7;
  --status-rapid: #4f7df5;
  --status-exp:   #f5a04f;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html, body {
  background: var(--bg-deep);
  color: var(--text-primary);
  font-family: 'Inter', system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

/* ---------- Section ---------- */
.linkup-release-timeline {
  position: relative;
  padding: clamp(80px, 10vw, 140px) 24px;
  background:
    radial-gradient(800px 400px at 90% 10%, rgba(79,125,245,0.08), transparent 60%),
    var(--bg-deep);
  overflow: hidden;
}
.rt-bg-noise {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(180deg, transparent 0, transparent 95%, var(--border) 95%, var(--border) 100%);
  background-size: 100% 56px;
  opacity: 0.35;
  pointer-events: none;
  mask-image: linear-gradient(180deg, transparent, #000 20%, #000 80%, transparent);
}

.release-timeline-container {
  max-width: 980px;
  margin: 0 auto;
  position: relative;
}

/* ---------- Header ---------- */
.section-header { margin-bottom: 64px; }

.rt-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 18px;
}
.rt-eyebrow-bar {
  width: 32px; height: 1px;
  background: linear-gradient(90deg, var(--accent), transparent);
}

.section-title {
  font-size: clamp(36px, 5.5vw, 64px);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1;
  color: var(--text-primary);
}
.rt-title-accent {
  font-family: 'JetBrains Mono', monospace;
  font-weight: 500;
  font-size: 0.78em;
  color: var(--accent);
  position: relative;
  padding-left: 14px;
  margin-left: 6px;
}
.rt-title-accent::before {
  content: '';
  position: absolute;
  left: 0; top: 50%;
  transform: translateY(-50%);
  width: 3px; height: 70%;
  background: linear-gradient(180deg, var(--accent), var(--accent-2));
  border-radius: 2px;
}

.rt-section-sub {
  margin-top: 18px;
  max-width: 560px;
  font-size: 15px;
  line-height: 1.65;
  color: var(--text-secondary);
}

/* ---------- Filter pills ---------- */
.rt-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 32px;
  padding: 6px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  width: max-content;
  max-width: 100%;
}
.rt-filter {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  font-family: 'Inter', sans-serif;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  background: transparent;
  border: 0;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background .25s, color .25s;
}
.rt-filter span {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  color: var(--text-dim);
  background: var(--bg-elevated);
  padding: 1px 7px;
  border-radius: 999px;
}
.rt-filter:hover { color: var(--text-primary); }
.rt-filter.is-active {
  background: var(--bg-elevated-2);
  color: var(--text-primary);
  box-shadow: inset 0 0 0 1px var(--border-strong);
}
.rt-filter.is-active span { color: var(--accent); background: rgba(79,125,245,0.12); }

/* ---------- Timeline ---------- */
.timeline-wrapper {
  position: relative;
  padding-left: 56px;
}

.rt-rail {
  position: absolute;
  left: 19px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--border-strong);
  border-radius: 2px;
  overflow: hidden;
}
.rt-rail-progress {
  position: absolute;
  left: 0; top: 0; right: 0;
  height: 0;
  background: linear-gradient(180deg, var(--accent), var(--accent-2));
  box-shadow: 0 0 12px var(--accent-glow);
  transition: height .3s ease;
}

/* ---------- Entry ---------- */
.timeline-entry {
  position: relative;
  margin-bottom: 28px;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .6s ease, transform .6s ease, max-height .4s ease, margin .4s ease;
}
.timeline-entry.is-visible { opacity: 1; transform: translateY(0); }
.timeline-entry.is-hidden {
  opacity: 0;
  max-height: 0;
  margin: 0;
  pointer-events: none;
  overflow: hidden;
}

/* Node on rail */
.rt-node {
  position: absolute;
  left: -45px;
  top: 22px;
  width: 18px; height: 18px;
  border-radius: 50%;
  background: var(--bg-deep);
  border: 2px solid var(--border-strong);
  display: grid;
  place-items: center;
  z-index: 2;
  transition: border-color .3s, box-shadow .3s;
}
.rt-node-inner {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--text-dim);
  transition: background .3s, box-shadow .3s;
}
.timeline-entry:hover .rt-node {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(79,125,245,0.15);
}
.timeline-entry:hover .rt-node-inner {
  background: var(--accent);
  box-shadow: 0 0 10px var(--accent);
}

/* ---------- Card ---------- */
.rt-card {
  position: relative;
  background: linear-gradient(180deg, var(--bg-surface), var(--bg-elevated));
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 22px 24px;
  transition: transform .3s, border-color .3s, box-shadow .3s;
  overflow: hidden;
}
.rt-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(400px 120px at var(--mx, 50%) var(--my, 0%), rgba(79,125,245,0.10), transparent 70%);
  opacity: 0;
  transition: opacity .3s;
  pointer-events: none;
}
.rt-card:hover {
  transform: translateY(-2px);
  border-color: rgba(79,125,245,0.4);
  box-shadow: var(--shadow-lg);
}
.rt-card:hover::before { opacity: 1; }

.rt-card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 14px;
}

.timeline-version {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  padding: 4px 10px;
  background: rgba(79,125,245,0.10);
  border: 1px solid rgba(79,125,245,0.25);
  border-radius: var(--radius-sm);
}

.timeline-status-badge {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  font-weight: 500;
  text-transform: lowercase;
  padding: 5px 10px;
  border-radius: 999px;
  border: 1px solid;
}
.rt-badge-dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: currentColor;
  box-shadow: 0 0 8px currentColor;
}
.timeline-status-badge[data-badge="Stable"] {
  color: var(--status-stable);
  background: rgba(34,211,167,0.08);
  border-color: rgba(34,211,167,0.3);
}
.timeline-status-badge[data-badge="Rapid Development"] {
  color: var(--status-rapid);
  background: rgba(79,125,245,0.08);
  border-color: rgba(79,125,245,0.3);
}
.timeline-status-badge[data-badge="Experimental"] {
  color: var(--status-exp);
  background: rgba(245,160,79,0.08);
  border-color: rgba(245,160,79,0.3);
}

/* Details */
.timeline-details { display: flex; flex-direction: column; gap: 6px; }
.timeline-release-name {
  font-size: 19px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  line-height: 1.3;
}
.timeline-release-date {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  color: var(--text-dim);
}

/* Footer tags */
.rt-card-foot {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px dashed var(--border);
}
.rt-tag {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  color: var(--text-secondary);
  padding: 3px 9px;
  background: var(--bg-elevated-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: color .2s, border-color .2s;
}
.rt-tag:hover { color: var(--accent); border-color: rgba(79,125,245,0.35); }

/* ---------- Responsive ---------- */
@media (max-width: 640px) {
  .timeline-wrapper { padding-left: 40px; }
  .rt-rail { left: 11px; }
  .rt-node { left: -37px; width: 16px; height: 16px; top: 20px; }
  .rt-card { padding: 18px 18px; }
  .rt-card-head { flex-direction: column; align-items: flex-start; gap: 8px; }
  .timeline-release-name { font-size: 17px; }
  .rt-filters { width: 100%; justify-content: space-between; }
  .rt-filter { padding: 7px 10px; font-size: 12px; }
}

@media (prefers-reduced-motion: reduce) {
  .timeline-entry { opacity: 1; transform: none; transition: none; }
  .rt-rail-progress { transition: none; }
}