/* Background section — 三不知 × 三不夠 */
.bg-section { background: var(--bg); }
.bg-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 48px;
  align-items: start;
  margin-bottom: 96px;
}
@media (max-width: 900px) {
  .bg-grid { grid-template-columns: 1fr; gap: 32px; }
}
.bg-column { display: flex; flex-direction: column; gap: 18px; }
.bg-col-head {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 12px;
}
.bg-col-head h3 {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 32px;
  margin: 0;
  letter-spacing: -0.01em;
}
.bg-item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 18px;
  padding: 24px;
  background: var(--bg-1);
  border: 1px solid var(--line);
  border-radius: 12px;
  transition: border-color 200ms, background 200ms;
}
.bg-item:hover {
  border-color: var(--accent-line);
  background: var(--bg-2);
}
.bg-item-num {
  font-family: var(--serif);
  font-style: italic;
  font-size: 28px;
  color: var(--ink-3);
  font-weight: 500;
  line-height: 1;
  padding-top: 4px;
}
.bg-item-title {
  font-size: 17px;
  font-weight: 500;
  color: var(--ink);
  margin-bottom: 6px;
}
.bg-item-desc {
  font-size: 14px;
  color: var(--ink-3);
  line-height: 1.6;
}
.bg-divider {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 80px;
  gap: 16px;
}
.bg-divider-line {
  flex: 1;
  width: 1px;
  background: linear-gradient(to bottom, transparent, var(--line) 40%, var(--line) 60%, transparent);
  min-height: 100px;
}
.bg-divider-mark {
  font-size: 32px;
  color: var(--accent);
  font-style: italic;
}
@media (max-width: 900px) {
  .bg-divider { display: none; }
}
.bg-quote {
  text-align: center;
  padding: 56px 32px;
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
  position: relative;
}
.bg-quote-mark {
  font-size: 80px;
  color: var(--accent);
  position: absolute;
  top: 28px;
  left: 50%;
  transform: translateX(-50%);
  opacity: 0.15;
  line-height: 1;
}
.bg-quote p {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(24px, 3vw, 36px);
  line-height: 1.4;
  letter-spacing: -0.01em;
  margin: 0;
  position: relative;
  color: var(--ink);
}
.bg-quote em {
  font-style: italic;
  color: var(--accent);
}

/* Who we are */
.who-section { background: var(--bg-1); }
.who-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 80px;
  align-items: center;
}
@media (max-width: 900px) {
  .who-grid { grid-template-columns: 1fr; gap: 48px; }
}
.who-statement-tag { margin-bottom: 28px; }
.who-quote {
  font-family: var(--serif);
  font-size: clamp(32px, 4vw, 48px);
  line-height: 1.2;
  letter-spacing: -0.015em;
  margin: 0 0 48px;
  font-weight: 500;
}
.who-quote em {
  font-style: italic;
  color: var(--accent);
}
.who-pillars {
  display: flex;
  gap: 40px;
}
.who-pillar { display: flex; flex-direction: column; gap: 4px; }
.who-pillar-num {
  font-family: var(--serif);
  font-size: 36px;
  color: var(--ink);
  font-weight: 500;
  letter-spacing: -0.01em;
}
.who-pillar-text {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.who-arch-frame {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--bg);
  padding: 8px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.arch-layer {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 16px;
  padding: 18px 20px;
  background: var(--bg-2);
  border-radius: 10px;
  position: relative;
}
.arch-layer.is-accent {
  background: linear-gradient(90deg, var(--accent-soft), transparent 60%);
  border: 1px solid var(--accent-line);
}
.arch-layer-id {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-4);
  letter-spacing: 0.08em;
}
.arch-layer-name {
  font-size: 16px;
  font-weight: 500;
  color: var(--ink);
}
.arch-layer-desc {
  font-size: 13px;
  color: var(--ink-3);
  margin-top: 2px;
}
.arch-layer-flow {
  position: absolute;
  bottom: -14px;
  left: 50%;
  transform: translateX(-50%);
  color: var(--ink-4);
  font-size: 14px;
  z-index: 2;
  background: var(--bg);
  width: 18px;
  height: 18px;
  border-radius: 999px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
}
.who-arch-caption {
  margin-top: 16px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-3);
  text-align: center;
}

/* Capabilities overview */
.cap-overview { padding: 100px 0 60px; }
.cap-overview-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
@media (max-width: 900px) {
  .cap-overview-grid { grid-template-columns: repeat(2, 1fr); }
}
.cap-overview-tile {
  background: var(--bg-1);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: all 200ms;
}
.cap-overview-tile:hover {
  border-color: var(--ink-4);
  transform: translateY(-2px);
}
.cap-overview-tile.is-feature {
  background: linear-gradient(180deg, var(--accent-soft), var(--bg-1));
  border-color: var(--accent-line);
}
.cap-overview-num {
  font-family: var(--serif);
  font-style: italic;
  font-size: 28px;
  color: var(--accent);
  font-weight: 500;
  letter-spacing: -0.01em;
}
.cap-overview-name {
  font-size: 17px;
  font-weight: 500;
  color: var(--ink);
}
.cap-overview-desc {
  font-size: 13px;
  color: var(--ink-3);
  line-height: 1.5;
}

/* Capability section */
.cap-section { padding: 100px 0; border-bottom: 1px solid var(--line-soft); }
.cap-section:nth-child(odd) { background: var(--bg-1); }
.cap-grid {
  display: grid;
  grid-template-columns: 1fr 1.15fr;
  gap: 80px;
  align-items: center;
}
.cap-section.is-reverse .cap-grid {
  grid-template-columns: 1.15fr 1fr;
}
.cap-section.is-reverse .cap-text { order: 2; }
.cap-section.is-reverse .cap-vis { order: 1; }
@media (max-width: 1024px) {
  .cap-grid, .cap-section.is-reverse .cap-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }
  .cap-section.is-reverse .cap-text,
  .cap-section.is-reverse .cap-vis { order: unset; }
}
.cap-eyebrow {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 24px;
}
.cap-code {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid var(--accent-line);
  padding: 4px 10px;
  border-radius: 4px;
}
.cap-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(32px, 4vw, 52px);
  line-height: 1.1;
  letter-spacing: -0.015em;
  margin: 0 0 24px;
}
.cap-title em {
  font-style: italic;
  color: var(--accent);
  font-size: 0.78em;
  font-weight: 500;
}
.cap-lede {
  font-size: 17px;
  color: var(--ink-2);
  line-height: 1.6;
  margin: 0 0 32px;
  max-width: 540px;
}
.cap-bullets {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.cap-bullets li {
  display: flex;
  gap: 12px;
  font-size: 15px;
  line-height: 1.55;
  color: var(--ink-2);
}
.cap-bullet-mark {
  color: var(--accent);
  flex-shrink: 0;
  margin-top: 2px;
}
.cap-bullets strong {
  color: var(--ink);
  font-weight: 500;
}

/* C1 Kanban */
.c1-kanban {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px;
}
.kanban-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line-soft);
}
.kanban-title { font-size: 14px; font-weight: 500; color: var(--ink); }
.kanban-meta { font-family: var(--mono); font-size: 11px; color: var(--ink-3); }
.kanban-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}
.kanban-col {
  background: var(--bg-1);
  border-radius: 10px;
  padding: 12px;
  min-height: 200px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.kanban-col.is-accent {
  background: linear-gradient(180deg, var(--accent-soft), var(--bg-1) 80%);
  border: 1px solid var(--accent-line);
}
.kanban-col-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  font-weight: 500;
  color: var(--ink-2);
  padding: 4px 4px 8px;
}
.kanban-count {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-3);
  background: var(--bg-2);
  padding: 1px 8px;
  border-radius: 999px;
}
.kanban-card {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: border-color 150ms;
}
.kanban-card:hover { border-color: var(--accent-line); }
.kanban-card.is-human { border-color: rgba(96,165,250,0.32); }
.kanban-card-id {
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.08em;
  color: var(--ink-4);
}
.kanban-card-title { font-size: 12px; color: var(--ink); line-height: 1.4; }
.kanban-card-foot {
  display: flex;
  align-items: center;
  gap: 6px;
}
.kanban-avatar {
  width: 16px; height: 16px; border-radius: 999px;
  font-size: 9px; color: #08130f;
  display: flex; align-items: center; justify-content: center;
  font-weight: 600;
}
.kanban-who { font-size: 11px; color: var(--ink-3); }
.kanban-progress {
  height: 2px;
  background: var(--bg-3);
  border-radius: 999px;
  overflow: hidden;
}
.kanban-progress-bar {
  height: 100%;
  background: var(--accent);
}

/* C2 Flow */
.c2-flow {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 28px;
}
.flow-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line-soft);
}
.flow-title { font-size: 14px; font-weight: 500; color: var(--ink); }
.flow-meta { font-family: var(--mono); font-size: 11px; color: var(--accent); }
.flow-steps { display: flex; flex-direction: column; gap: 4px; }
.flow-step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  padding: 14px 12px;
  border-radius: 8px;
  position: relative;
  transition: background 150ms;
}
.flow-step:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 27px;
  top: 38px;
  bottom: -4px;
  width: 1px;
  background: var(--line);
}
.flow-step.is-done:not(:last-child)::after { background: var(--accent); opacity: 0.4; }
.flow-step.is-active { background: var(--warm-soft); }
.flow-step-dot {
  width: 28px; height: 28px;
  border-radius: 999px;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono);
  font-size: 11px;
  color: #08130f;
  font-weight: 600;
  z-index: 2;
  position: relative;
}
.flow-step.is-active .flow-step-dot { animation: pulse-soft 2s infinite; }
.flow-step-label { font-size: 14px; font-weight: 500; color: var(--ink); }
.flow-step-detail { font-size: 12px; color: var(--ink-3); margin-top: 2px; }
.flow-foot {
  display: flex;
  gap: 32px;
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--line-soft);
}
.flow-foot-stat { display: flex; flex-direction: column; gap: 2px; }
.flow-foot-label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.flow-foot-num {
  font-family: var(--serif);
  font-size: 24px;
  font-weight: 500;
  color: var(--ink);
}

/* C3 Memory cards */
.c3-memory {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.mem-card {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 20px;
  transition: border-color 200ms;
}
.mem-card:hover { border-color: var(--ink-4); }
.mem-card-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}
.mem-card-icon {
  width: 36px; height: 36px;
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--serif);
  font-style: italic;
  font-size: 18px;
  font-weight: 500;
}
.mem-card-title { font-size: 15px; font-weight: 500; color: var(--ink); }
.mem-card-meta { font-size: 12px; color: var(--ink-3); margin-top: 2px; }
.mem-rows { display: flex; flex-direction: column; gap: 6px; }
.mem-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 6px 0;
  font-size: 13px;
  border-bottom: 1px solid var(--line-soft);
}
.mem-row:last-child { border-bottom: none; }
.mem-row-key { color: var(--ink-3); }
.mem-row-val { color: var(--ink); font-family: var(--mono); font-size: 12px; }
.mem-sources {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 12px;
}
.mem-source {
  font-family: var(--mono);
  font-size: 11px;
  padding: 4px 8px;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 4px;
  color: var(--ink-2);
}
.mem-permission {
  display: flex;
  gap: 6px;
}
.mem-perm-tag {
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 999px;
  background: var(--bg-2);
  color: var(--ink-3);
  border: 1px solid var(--line);
}
.mem-perm-tag.is-self {
  background: var(--accent-soft);
  color: var(--accent);
  border-color: var(--accent-line);
}
.mem-skills { display: flex; flex-direction: column; gap: 10px; }
.mem-skill {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 10px;
  align-items: center;
}
.mem-skill-dot {
  width: 8px; height: 8px;
  border-radius: 999px;
  background: var(--violet);
}
.mem-skill-name { font-size: 13px; color: var(--ink); }
.mem-skill-meta { font-size: 11px; color: var(--ink-3); margin-top: 2px; }

/* C4 Models */
.c4-models {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.model-route {
  background: var(--bg);
  border: 1px solid var(--accent-line);
  border-radius: 12px;
  padding: 20px;
}
.model-route-head {
  display: flex;
  justify-content: space-between;
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line-soft);
}
.model-route-title { font-size: 14px; font-weight: 500; color: var(--ink); }
.model-route-rules {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}
.route-rule {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  background: var(--bg-1);
  border-radius: 8px;
  font-size: 12px;
}
.route-task { color: var(--ink-3); }
.route-arrow { color: var(--accent); font-family: var(--mono); }
.route-target { color: var(--ink); font-weight: 500; }
.model-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
}
.model-tile {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 12px;
  transition: border-color 150ms;
}
.model-tile:hover { border-color: var(--accent-line); }
.model-tile.is-private { border-color: rgba(167,139,250,0.32); }
.model-tile-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 4px;
}
.model-tile-name { font-size: 13px; font-weight: 500; color: var(--ink); }
.model-tile-group {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.06em;
  padding: 2px 6px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
}
.model-tile-group.is-private {
  background: rgba(167,139,250,0.14);
  color: var(--violet);
}
.model-tile-detail { font-size: 11px; color: var(--ink-3); font-family: var(--mono); }