/* ─── Year Filter ─── */
.year-filter {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 48px;
  flex-wrap: wrap;
}
.year-btn {
  padding: 8px 20px;
  border-radius: 980px;
  border: 1px solid var(--color-border);
  background: transparent;
  color: var(--color-text-secondary);
  font-size: 14px;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.3s;
  letter-spacing: -0.01em;
}
.year-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}
.year-btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

/* ─── Timeline ─── */
.timeline {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
}
.timeline::before {
  content: '';
  position: absolute;
  left: 28px;
  top: 0; bottom: 0;
  width: 1.5px;
  background: linear-gradient(to bottom, var(--color-accent), var(--color-border-light));
}

.timeline-year {
  position: relative;
  margin-bottom: 8px;
}
.timeline-year-label {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 8px 0;
  position: relative;
  z-index: 2;
}
.timeline-year-dot {
  width: 56px; height: 56px;
  border-radius: 50%;
  background: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 700;
  color: #fff;
  flex-shrink: 0;
  box-shadow: 0 4px 20px rgba(41,151,255,0.25);
}
.timeline-year-text {
  font-size: clamp(20px, 2.5vw, 26px);
  font-weight: 700;
  color: var(--color-text-primary);
  letter-spacing: -0.02em;
}

.timeline-items {
  padding-left: 80px;
  padding-bottom: 32px;
}

.timeline-card {
  background: var(--color-white);
  border-radius: 16px;
  padding: 24px 28px;
  margin-bottom: 12px;
  border: 0.5px solid var(--color-border-light);
  transition: all 0.3s cubic-bezier(.25,.1,.25,1);
  position: relative;
}
.timeline-card:hover {
  transform: translateX(4px);
  box-shadow: 0 8px 32px rgba(0,0,0,0.06);
  border-color: var(--color-accent);
}
.timeline-card-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}
.timeline-client {
  font-size: clamp(15px, 1.6vw, 17px);
  font-weight: 700;
  color: var(--color-text-primary);
  letter-spacing: -0.01em;
}
.timeline-badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 980px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.01em;
}
.badge-public {
  background: #e8f4fd;
  color: #0071e3;
}
.badge-private {
  background: #f0faf0;
  color: #1d8a3e;
}
.badge-b2c {
  background: #fef3e8;
  color: #c25e00;
}
.badge-ongoing {
  background: #fff3e0;
  color: #e65100;
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.7; }
}
.timeline-project {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.5;
  letter-spacing: -0.01em;
}
.timeline-detail {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  margin-top: 10px;
  padding-top: 10px;
  border-top: 0.5px solid var(--color-border-light);
}
.timeline-detail-icon {
  flex-shrink: 0;
  width: 18px;
  height: 18px;
  margin-top: 1px;
  color: var(--color-text-muted);
}
.timeline-detail p {
  font-size: 13px;
  color: var(--color-text-muted);
  line-height: 1.5;
}

/* ─── Client Section ─── */
.client-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
  max-width: 800px;
  margin: 0 auto;
}
.client-chip {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 16px;
  background: rgba(255,255,255,0.04);
  border: 0.5px solid rgba(255,255,255,0.08);
  border-radius: 12px;
  font-size: 13px;
  font-weight: 500;
  color: rgba(255,255,255,0.7);
  transition: all 0.3s;
}
.client-chip:hover {
  background: rgba(255,255,255,0.08);
  color: #fff;
}
.client-chip svg {
  width: 16px; height: 16px;
  opacity: 0.5;
}

/* ─── CTA Bottom ─── */
.cta-bottom {
  text-align: center;
  padding: 80px 24px;
  background: linear-gradient(180deg, var(--color-fill) 0%, var(--color-white) 100%);
}

/* ─── Responsive ─── */
@media (max-width: 834px) {
  .timeline::before { left: 20px; }
  .timeline-year-dot { width: 40px; height: 40px; font-size: 13px; }
  .timeline-items { padding-left: 60px; }
}
@media (max-width: 480px) {
  .timeline::before { left: 16px; }
  .timeline-year-dot { width: 32px; height: 32px; font-size: 11px; }
  .timeline-items { padding-left: 48px; }
  .timeline-card { padding: 20px; }
  .timeline-card-header { flex-direction: column; align-items: flex-start; gap: 6px; }
  .client-grid { grid-template-columns: repeat(2, 1fr); }
}