/* ============================================================
   COMPONENTS — Cards, tags, chips, panels, timeline, roadmap
   ============================================================ */


/* ---- Cards ---- */

.card {
  background: var(--surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  transition:
    border-color var(--dur-normal) ease,
    box-shadow var(--dur-normal) ease;
}

.card:hover {
  border-color: var(--border);
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.04);
}

.card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-sm);
  margin-bottom: 0.5rem;
}

.card p {
  font-size: 0.88rem;
  color: var(--text-dim);
  line-height: 1.65;
}

.card .links {
  margin-top: 0.65rem;
  display: flex;
  gap: 0.65rem;
  flex-wrap: wrap;
}

.card .links a {
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--accent);
}
.card .links a::after {
  content: ' \2197';
  font-size: 0.7em;
  opacity: 0.6;
}

/* Highlight variant */
.card--highlight {
  border-left: 3px solid var(--accent);
  background: linear-gradient(135deg, var(--accent-bg), var(--surface) 60%);
}

.card--highlight h3 {
  color: var(--accent);
  margin-bottom: 0.5rem;
}


/* ---- Tags ---- */

.tag {
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.18rem 0.5rem;
  border-radius: 100px;
  white-space: nowrap;
  flex-shrink: 0;
}

.tag-core    { background: var(--accent-bg-strong); color: var(--accent); }
.tag-tool    { background: rgba(9, 146, 104, 0.1);  color: var(--green); }
.tag-paper   { background: rgba(230, 119, 0, 0.1);  color: var(--gold); }
.tag-person  { background: rgba(166, 30, 77, 0.08);  color: var(--pink); }
.tag-org     { background: rgba(12, 133, 153, 0.1);  color: var(--cyan); }
.tag-problem { background: rgba(201, 42, 42, 0.08);  color: var(--red); }
.tag-method  { background: rgba(217, 72, 15, 0.08);  color: var(--orange); }


/* ---- Concept Map ---- */

.concept-map {
  background: var(--surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  margin: var(--space-lg) 0;
}

.concept-layer {
  margin-bottom: var(--space-xl);
}
.concept-layer:last-child { margin-bottom: 0; }

.concept-layer p {
  color: var(--text);
  font-size: 0.92rem;
  line-height: 1.7;
  max-width: 60ch;
}

.layer-label {
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 0.7rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border-dim);
}

.concept-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.concept-chip {
  background: var(--surface-2);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius-md);
  padding: 0.4rem 0.85rem;
  font-size: 0.84rem;
  color: var(--text);
  cursor: pointer;
  transition: all var(--dur-normal) ease;
}

.concept-chip:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-bg);
}

.concept-chip:active {
  transform: scale(0.97);
}

/* Non-clickable concept chip (goals, etc.) */
.concept-chip--static {
  cursor: default;
}
.concept-chip--static:hover {
  border-color: var(--border-dim);
  color: var(--text);
  background: var(--surface-2);
}
.concept-chip--static:active {
  transform: none;
}

/* Arrow labels between concept layers */
.arrow-label {
  font-size: 0.65rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  text-align: center;
  padding: 0.4rem 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}
.arrow-label::before,
.arrow-label::after {
  content: '';
  height: 1px;
  width: 28px;
  background: var(--border);
}


/* ---- Detail Panel ---- */

.detail-panel {
  background: var(--surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius-lg);
  padding: 0;
  margin-top: var(--space-md);
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  transition:
    max-height var(--dur-slow) var(--ease-out),
    opacity var(--dur-normal) ease,
    padding var(--dur-slow) var(--ease-out);
}

.detail-panel.visible {
  max-height: 600px;
  opacity: 1;
  padding: var(--space-xl);
  border-left: 3px solid var(--accent);
}

.detail-panel h3 {
  font-size: 1.1rem;
  margin-bottom: 0.3rem;
}

.detail-panel .detail-tag {
  display: inline-block;
  margin-bottom: var(--space-md);
}

.detail-panel p,
.detail-panel li {
  font-size: 0.88rem;
  color: var(--text-dim);
  line-height: 1.65;
}

.detail-panel ul {
  padding-left: 1.4rem;
  margin: 0.4rem 0;
}
.detail-panel li {
  margin-bottom: 0.25rem;
}
.detail-panel li::marker {
  color: var(--accent);
}

.detail-panel .prereqs {
  margin-top: var(--space-lg);
  padding: var(--space-md);
  background: var(--surface-2);
  border-radius: var(--radius-md);
  border-left: 2px solid var(--accent-dim);
}

.detail-panel .prereqs-label {
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  margin-bottom: 0.25rem;
}


/* ---- Timeline ---- */

.timeline {
  position: relative;
  padding-left: 2.5rem;
  margin: var(--space-lg) 0;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 0;
  bottom: 0;
  width: 1.5px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  margin-bottom: var(--space-xl);
  padding-left: 1.25rem;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -2.5rem;
  top: 0.35rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  border: 2px solid var(--border);
  background: var(--bg);
  z-index: 1;
}

.timeline-item.major::before {
  background: var(--accent);
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-bg-strong);
}

.timeline-date {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.15rem;
}

.timeline-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-bright);
  margin-bottom: 0.25rem;
}

.timeline-desc {
  font-size: 0.86rem;
  color: var(--text-dim);
  line-height: 1.6;
}

.timeline-authors {
  font-size: 0.76rem;
  color: var(--text-muted);
  font-style: italic;
  margin-top: 0.2rem;
}


/* ---- Roadmap ---- */

.roadmap {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 0.85rem;
}

.roadmap-step {
  background: var(--surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  padding-top: 1.5rem;
  position: relative;
  transition:
    border-color var(--dur-normal) ease,
    box-shadow var(--dur-normal) ease;
}

.roadmap-step:hover {
  border-color: var(--border);
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.04);
}

.step-num {
  position: absolute;
  top: -9px;
  left: 1rem;
  font-size: 0.68rem;
  font-weight: 700;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent);
  color: white;
}

.roadmap-step h3 {
  font-size: 0.95rem;
  margin-bottom: 0.3rem;
}

.roadmap-step .time {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.03em;
  margin-bottom: 0.4rem;
}

.roadmap-step p {
  font-size: 0.86rem;
  color: var(--text-dim);
}

.roadmap-step ul {
  padding-left: 1.1rem;
  margin-top: 0.4rem;
}

.roadmap-step li {
  font-size: 0.84rem;
  color: var(--text-dim);
  margin-bottom: 0.2rem;
  line-height: 1.55;
}
.roadmap-step li::marker { color: var(--accent); }

.roadmap-step a { color: var(--accent); }


/* ---- Info Box ---- */

.info-box {
  background: var(--surface);
  border: 1px solid var(--border-dim);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
}

.info-box p {
  font-size: 0.88rem;
  color: var(--text-dim);
  line-height: 1.65;
}


/* ---- Epigraph ---- */

.epigraph {
  padding: var(--space-2xl) 0 var(--space-xl);
}

.epigraph blockquote {
  font-family: var(--font-display);
  font-style: italic;
  font-size: clamp(1.1rem, 2vw, 1.3rem);
  line-height: 1.6;
  color: var(--text-bright);
  max-width: 540px;
}

.epigraph cite {
  display: block;
  margin-top: var(--space-sm);
  font-family: var(--font-body);
  font-style: normal;
  font-size: 0.8rem;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}