/* ══════════════════════════════════════════
   Experience Section
══════════════════════════════════════════ */
#experience {
  background: var(--bg-primary);
  border-top: 1px solid var(--border);
}

/* Two-column layout: main + sticky certs */
.exp-layout {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 4rem;
  align-items: start;
}

.exp-main {
  position: relative;
  padding-left: 2.5rem;
}

/* Vertical timeline bar */
.exp-main::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.5rem;
  bottom: 0.5rem;
  width: 2px;
  background: var(--border);
  opacity: 0.5;
}

/* ── Group labels ── */
.exp-group {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-bottom: 3rem;
}

.exp-group:last-child {
  margin-bottom: 0;
}

.exp-group-label {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 0.5rem;
}

.exp-group-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
  box-shadow: 0 0 10px var(--accent-glow);
}

.exp-group-dot--edu {
  background: var(--text-dim);
  box-shadow: none;
}

/* ── Experience Card (Dev Panel Redesign) ── */
.exp-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
  transition: all var(--transition-smooth);
  position: relative;
  overflow: visible; /* Changed from hidden to allow checkpoint dots to show */
  /* reveal */
  opacity: 0;
  transform: translateY(25px);
}

/* Checkpoint indicator */
.exp-card::after {
  content: "";
  position: absolute;
  left: -2.5rem;
  top: 2.5rem;
  width: 10px;
  height: 10px;
  background: var(--bg-primary);
  border: 2px solid var(--accent);
  border-radius: 50%;
  transform: translateX(-50%);
  z-index: 2;
  transition: all var(--transition-smooth);
}

.exp-card:hover::after {
  background: var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
  transform: translateX(-50%) scale(1.3);
}

.exp-card--edu::after {
  border-color: var(--text-dim);
}

.exp-card--edu:hover::after {
  background: var(--text-dim);
  box-shadow: none;
}

.exp-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 100%;
  background: var(--accent);
  opacity: 0;
  transition: opacity 0.4s;
  border-radius: 12px 0 0 12px;
}

.exp-card.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.exp-card:hover {
  border-color: var(--border-accent);
  box-shadow: var(--shadow-premium);
  transform: translateY(-6px) scale(1.01);
}

.exp-card:hover::before {
  opacity: 1;
}

.exp-card--edu {
  background: var(--bg-secondary);
  border-style: dashed;
}

.exp-card--edu:hover {
  border-style: solid;
}

.exp-card-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
}

.exp-card-left {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.exp-card-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--text-primary);
  line-height: 1.3;
  transition: color var(--transition-smooth);
}

.exp-card:hover .exp-card-title {
  color: var(--accent);
}

.exp-card-org {
  font-size: 0.95rem;
  color: var(--accent);
  font-family: var(--font-body);
  font-weight: 500;
}

.exp-card-right {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.4rem;
  flex-shrink: 0;
}

.exp-card-period {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  white-space: nowrap;
  background: var(--tag-bg);
  border: 1px solid var(--border);
  padding: 0.25rem 0.75rem;
  border-radius: 6px;
}

.exp-card-location {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--text-dim);
  letter-spacing: 0.04em;
}

.exp-card-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.75;
}

.exp-card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.5rem;
}

.exp-tag {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  padding: 0.25rem 0.75rem;
  border-radius: 4px;
  background: var(--accent-light);
  color: var(--accent);
  border: 1px solid var(--border-accent);
  letter-spacing: 0.03em;
  transition: all 0.3s ease;
}

.exp-card:hover .exp-tag {
  background: rgba(var(--accent-rgb), 0.15);
  border-color: var(--accent);
}

/* ── Sticky Certifications Panel (System Card) ── */
.certs-sticky-wrap {
  position: sticky;
  top: 110px;
  align-self: start;
  will-change: transform;
}

.certs-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  transition: all var(--transition-smooth);
  box-shadow: var(--shadow-lg);
  position: relative;
}

.certs-panel:hover {
  border-color: var(--border-accent);
  box-shadow: var(--shadow-premium);
  transform: translateY(-5px);
}

.certs-panel-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.03);
  backdrop-filter: blur(8px);
}

.certs-panel:hover .certs-panel-header {
  background: var(--accent-light);
  border-bottom-color: var(--border-accent);
}

.certs-panel-icon {
  width: 32px;
  height: 32px;
  background: var(--accent-light);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  border: 1px solid var(--border-accent);
}

.certs-panel-icon svg {
  width: 16px;
  height: 16px;
  color: var(--accent);
}

.certs-panel-title {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text-primary);
  font-weight: 600;
}

.cert-list {
  display: flex;
  flex-direction: column;
}

/* ── Cert Card ── */
.cert-card {
  position: relative;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border);
  transition: all var(--transition-smooth);
  cursor: default;
  /* reveal */
  opacity: 0;
  transform: translateX(15px);
}

.cert-card.is-visible {
  opacity: 1;
  transform: translateX(0);
}

.cert-card:last-child {
  border-bottom: none;
}

.cert-card:hover {
  background: rgba(var(--accent-rgb), 0.05);
  padding-left: 1.75rem;
}

.cert-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--accent);
  transform: scaleY(0);
  transition: transform 0.4s var(--ease-out-expo);
}

.cert-card:hover::before {
  transform: scaleY(1);
}

.cert-card-inner {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.cert-card-title {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-primary);
  line-height: 1.4;
  transition: color var(--transition-smooth);
}

.cert-card:hover .cert-card-title {
  color: var(--accent);
}

.cert-card-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
}

.cert-issuer {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-dim);
  letter-spacing: 0.03em;
}

.cert-year {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--accent);
  background: var(--accent-light);
  border: 1px solid var(--border-accent);
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
}

/* ── Responsive ── */
@media (max-width: 960px) {
  .exp-layout {
    grid-template-columns: 1fr;
    gap: 3rem;
  }

  .exp-main {
    padding-left: 2rem;
  }

  .exp-card::after {
    left: -2rem;
  }

  .certs-sticky-wrap {
    position: relative;
    top: auto;
  }
}