/* ===========================================================
   Timeline page — scroll storytelling + backpack
   =========================================================== */

.timeline-intro {
  min-height: 85vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 140px var(--gutter) 80px;
  position: relative;
  border-bottom: 1px solid var(--border);
}

.timeline-intro h1 {
  font-size: clamp(3rem, 10vw, 9rem);
  line-height: 0.85;
  letter-spacing: -0.04em;
  margin-bottom: 24px;
}
.timeline-intro h1 em { color: var(--accent); font-style: italic; }

.timeline-intro p {
  max-width: 58ch;
  color: var(--fg-muted);
  font-size: clamp(1rem, 1.3vw, 1.2rem);
  margin-top: 16px;
}

.timeline-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  margin-top: 48px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--fg-muted);
}
.timeline-legend span { display: flex; align-items: center; gap: 8px; }
.timeline-legend span::before {
  content: "";
  width: 10px;
  height: 10px;
  background: var(--accent);
  border: 1px solid var(--accent);
}
.timeline-legend span.secondary::before {
  background: var(--accent-2);
  border-color: var(--accent-2);
}

/* --- sticky backpack --- */

.backpack {
  position: fixed;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  width: clamp(280px, 28vw, 380px);
  padding: 22px 20px;
  background: var(--bg-paper);
  border: 2px solid var(--border-strong);
  box-shadow: 8px 8px 0 var(--accent);
  z-index: 50;
  max-height: 72vh;
  display: flex;
  flex-direction: column;
  gap: 14px;
  transition: transform var(--t-med), opacity var(--t-med), box-shadow var(--t-med);
}
.backpack.pulse { box-shadow: 12px 12px 0 var(--accent); }

.backpack-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  border-bottom: 1px dashed var(--border);
  padding-bottom: 10px;
}
.backpack-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  letter-spacing: -0.02em;
}
.backpack-count {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--fg-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.backpack-count strong { color: var(--accent); font-weight: 500; }

.backpack-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  overflow-y: auto;
  overflow-x: hidden;
  flex: 1;
  scrollbar-width: thin;
  scrollbar-color: var(--fg-dim) transparent;
}
.backpack-tags::-webkit-scrollbar { width: 4px; }
.backpack-tags::-webkit-scrollbar-thumb { background: var(--fg-dim); }

.backpack-tags .bp-tag {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 4px 8px;
  border: 1px solid var(--accent);
  color: var(--accent);
  background: transparent;
  animation: pop 400ms cubic-bezier(0.16, 1.3, 0.3, 1) both;
}
@keyframes pop {
  from { opacity: 0; transform: scale(0.5); }
  to { opacity: 1; transform: scale(1); }
}

.backpack-empty {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--fg-dim);
  font-style: italic;
}

@media (max-width: 1024px) {
  .backpack {
    position: fixed;
    right: 12px;
    top: auto;
    bottom: 16px;
    transform: none;
    width: calc(100vw - 24px);
    max-width: 360px;
    max-height: 32vh;
    box-shadow: 6px 6px 0 var(--accent);
  }
}

/* --- timeline story --- */

.timeline-track {
  position: relative;
  padding: 60px 0;
}

.timeline-year-marker {
  position: sticky;
  top: 80px;
  z-index: 5;
  padding: 24px var(--gutter);
  display: flex;
  align-items: baseline;
  gap: 24px;
  background: linear-gradient(to bottom, var(--bg) 60%, transparent);
  pointer-events: none;
}
.timeline-year-label {
  font-family: var(--font-display);
  font-size: clamp(3rem, 8vw, 7rem);
  line-height: 0.85;
  color: var(--fg-dim);
  letter-spacing: -0.04em;
  transition: color var(--t-med);
}
.timeline-year-label.active {
  color: var(--accent);
}

.story-section {
  min-height: 110vh;
  display: flex;
  align-items: center;
  padding: 80px var(--gutter);
  position: relative;
  border-top: 1px dashed var(--border);
}

.story-grid {
  width: 100%;
  max-width: 900px;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 40px;
  align-items: start;
}
.story-grid .story-year {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--fg-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  position: relative;
  padding-right: 20px;
  border-right: 1px solid var(--border);
  min-width: 90px;
}
.story-grid .story-year::before {
  content: "";
  position: absolute;
  right: -6px;
  top: 6px;
  width: 11px;
  height: 11px;
  background: var(--accent);
  border: 2px solid var(--bg);
  border-radius: 50%;
}

.story-content {
  max-width: 60ch;
}
.story-category {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 12px;
}
.story-title {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 5vw, 4rem);
  line-height: 0.95;
  margin-bottom: 18px;
  letter-spacing: -0.02em;
}
.story-title em { color: var(--accent); font-style: italic; }
.story-tagline {
  font-size: 1.15rem;
  color: var(--fg);
  margin-bottom: 18px;
  max-width: 55ch;
}
.story-body {
  color: var(--fg-muted);
  font-size: 1rem;
  margin-bottom: 24px;
  max-width: 60ch;
}

.story-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 28px;
}

.story-skills {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.story-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  border-bottom: 1px solid var(--accent);
  padding-bottom: 3px;
  margin-top: 20px;
}

/* highlight on active */
.story-section.is-active .story-title {
  color: var(--fg);
}
.story-section.is-active .story-grid .story-year::before {
  box-shadow: 0 0 0 4px rgba(212, 255, 0, 0.15);
}

/* end card */
.timeline-end {
  padding: 120px var(--gutter);
  text-align: center;
  border-top: 1px solid var(--border);
}
.timeline-end h2 {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 6vw, 5rem);
  line-height: 0.9;
  margin-bottom: 20px;
}
.timeline-end h2 em { color: var(--accent); font-style: italic; }
.timeline-end p {
  color: var(--fg-muted);
  max-width: 54ch;
  margin: 0 auto 40px;
}

/* floating skills flying into backpack */
.flying-skill {
  position: fixed;
  pointer-events: none;
  z-index: 60;
  will-change: transform, opacity;
}

@media (max-width: 760px) {
  .timeline-intro {
    min-height: auto;
    padding: 120px var(--gutter) 56px;
  }
  .timeline-intro h1 { font-size: clamp(2.8rem, 13vw, 4.6rem); }
  .timeline-intro p { font-size: 0.95rem; }
  .timeline-legend { gap: 10px; margin-top: 24px; }
  .timeline-legend span { font-size: 0.62rem; }

  .backpack {
    right: 10px;
    left: 10px;
    bottom: 10px;
    width: auto;
    max-width: none;
    padding: 12px 14px;
    max-height: 26vh;
    box-shadow: 4px 4px 0 var(--accent);
  }
  .backpack-title { font-size: 1rem; }
  .backpack-count { font-size: 0.6rem; }
  .backpack-tags .bp-tag { font-size: 0.55rem; padding: 3px 6px; }
  .backpack-empty { font-size: 0.62rem; }

  .timeline-track { padding: 20px 0 240px; }
  .story-grid {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 0 var(--gutter);
  }
  .story-grid .story-year {
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding: 0 0 8px;
    min-width: 0;
  }
  .story-grid .story-year::before { display: none; }
  .timeline-year-marker { position: static; padding: 16px var(--gutter); }
  .timeline-year-label { font-size: clamp(2.4rem, 10vw, 4rem); }
  .story-section {
    min-height: auto;
    padding: 40px 0;
  }
  .story-title { font-size: clamp(1.7rem, 7vw, 2.6rem); }
  .story-tagline { font-size: 0.98rem; }
  .story-body { font-size: 0.88rem; }
  .story-skills { gap: 6px; }
  .skill-tag { font-size: 0.6rem; padding: 5px 9px; }
  .story-tech { gap: 4px; }

  .timeline-end { padding: 80px var(--gutter) 140px; }
  .timeline-end h2 { font-size: clamp(2rem, 7vw, 3rem); }
}