/* ALYNTE Homepage — mechanism diagram & narrative visuals */

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.section-eyebrow {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 10px;
}

/* ── §02 Consequence gap ── */
.gap-visual {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  gap: 12px;
  align-items: center;
  max-width: 820px;
  margin: 0 auto;
  text-align: center;
}

.gap-step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px 16px;
}

.gap-step--warn {
  border-color: rgba(217, 119, 6, 0.35);
  background: rgba(217, 119, 6, 0.04);
}

.gap-label {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.gap-value {
  font-size: 1.125rem;
  font-weight: 700;
}

.gap-value.warn { color: var(--warning); }

.gap-arrow {
  color: var(--text-muted);
  font-size: 18px;
  font-weight: 600;
}

.gap-note {
  max-width: 560px;
  margin: 24px auto 0;
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* ── §04 Mechanism diagram ── */
.mechanism-section {
  background: var(--surface);
}

.mechanism {
  max-width: 960px;
  margin: 0 auto;
  text-align: left;
}

.mechanism-rail {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: center;
  margin-bottom: 20px;
}

.mech-stage-btn {
  font: inherit;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 8px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--background);
  color: var(--text-muted);
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
}

.mech-stage-btn:hover,
.mech-stage-btn:focus-visible {
  border-color: var(--accent);
  color: var(--accent);
  outline: none;
}

.mech-stage-btn.active {
  background: rgba(37, 99, 235, 0.08);
  border-color: rgba(37, 99, 235, 0.35);
  color: var(--accent);
}

.mechanism-viewport {
  background: var(--background);
  border: 1px solid var(--border);
  border-radius: 16px;
  height: 400px;
  padding: 20px 24px 16px;
  position: relative;
  overflow: hidden;
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
}

.mech-panels-stack {
  flex: 1;
  position: relative;
  min-height: 0;
}

.mech-panel {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.35s ease, visibility 0.35s ease;
}

.mech-panel.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.mech-stage-body {
  flex: 1;
  min-height: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.mech-canvas {
  width: 100%;
  max-height: 100%;
  min-height: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  overflow: hidden;
}

.mech-panel--enter .mech-chip--float {
  animation: chipAppear 0.45s ease both;
}

.mech-panel--enter .mech-chain-link {
  animation: edgePulse 1s ease 2;
}

.mech-stage-indicator {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  text-align: center;
  margin-top: 14px;
}

/* Stage 1 signals canvas */
.mech-canvas--signals {
  flex-direction: column;
  gap: 8px;
}

.mech-svg {
  width: 100%;
  max-width: 480px;
  max-height: 110px;
  height: auto;
}

.mech-svg-line {
  stroke: var(--accent);
  stroke-width: 1.5;
  stroke-dasharray: 6 4;
  opacity: 0.5;
  animation: vizDash 2s linear infinite;
}

.mech-svg-hub {
  fill: rgba(37, 99, 235, 0.12);
  stroke: var(--accent);
  stroke-width: 2;
}

.mech-signal-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  max-width: 480px;
}

.mech-chip--float {
  font-size: 11px;
  padding: 8px 12px;
}

/* Stage 2 normalize */
.mech-converge {
  text-align: center;
  max-width: 420px;
  width: 100%;
}

.mech-converge-from {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-bottom: 12px;
}

.mech-chip-sm {
  font-size: 11px;
  font-weight: 600;
  padding: 8px 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--surface);
}

.mech-converge-arrow {
  color: var(--accent);
  font-size: 20px;
  font-weight: 700;
  margin: 8px 0;
}

.mech-converge-to {
  background: var(--surface);
  border: 1px solid rgba(37, 99, 235, 0.3);
  border-radius: 12px;
  padding: 16px;
}

.mech-converge-to strong {
  display: block;
  font-size: 14px;
  margin-bottom: 4px;
}

.mech-converge-to span {
  font-size: 12px;
  color: var(--text-secondary);
}

/* Stage 3 — single horizontal relationship chain */
.mech-canvas--relate {
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.mech-chain-h {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: nowrap;
  gap: 4px;
  width: 100%;
  max-width: 100%;
}

.mech-canvas--relate .mech-chain-node {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 5px 8px;
  text-align: center;
  flex: 0 1 auto;
  min-width: 0;
}

.mech-canvas--relate .mech-chain-node small {
  display: block;
  font-size: 7px;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 2px;
  white-space: nowrap;
}

.mech-canvas--relate .mech-chain-node strong {
  display: block;
  font-size: 10px;
  line-height: 1.2;
  white-space: nowrap;
}

.mech-chain-link {
  text-align: center;
  font-size: 10px;
  font-weight: 600;
  color: var(--accent);
  padding: 2px 0;
}

.mech-canvas--relate .mech-chain-link--h {
  font-size: 12px;
  padding: 0 1px;
  flex-shrink: 0;
  line-height: 1;
}

/* Stage 4 — evidence vertical stack */
.mech-evidence-stack {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  width: 100%;
  max-width: 320px;
}

.mech-ev-card {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 14px;
  text-align: center;
}

.mech-ev-card strong {
  display: block;
  font-size: 13px;
  margin-bottom: 2px;
}

.mech-ev-card span {
  display: block;
  font-size: 11px;
  color: var(--text-secondary);
}

.mech-ev-connector {
  color: var(--accent);
  font-size: 14px;
  font-weight: 700;
  line-height: 1;
}

.mech-ev-rel {
  text-align: center;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  padding: 6px 10px;
  background: var(--surface);
  border-radius: 8px;
  border: 1px dashed var(--border);
  width: 100%;
}

.mech-finding {
  width: 100%;
  text-align: center;
  font-size: 13px;
  font-weight: 700;
  padding: 10px 12px;
  border-radius: 10px;
  background: rgba(217, 119, 6, 0.08);
  color: var(--warning);
  border: 1px solid rgba(217, 119, 6, 0.25);
}

/* Stage 5 — truth composition (centered within stage body) */
.mech-panel[data-panel="4"] .mech-stage-body {
  justify-content: center;
  align-items: center;
}

.mech-canvas--truth {
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100%;
}

.mech-truth-stack {
  display: flex;
  flex-direction: column;
  gap: 10px;
  width: 100%;
  max-width: 400px;
  margin: 0 auto;
}

.mech-truth-statement {
  text-align: center;
  font-size: 14px;
  font-weight: 700;
  padding: 10px 12px;
  margin-bottom: 0;
  border-radius: 10px;
  background: rgba(217, 119, 6, 0.08);
  color: var(--warning);
}

.mech-example-note {
  font-size: 10px;
  color: var(--text-muted);
  text-align: center;
  margin-top: 0;
  letter-spacing: 0.04em;
}

.mech-conf-compare {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 16px;
  align-items: center;
  width: 100%;
  max-width: 520px;
}

.mech-conf-col {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px;
  text-align: center;
}

.mech-conf-col--low {
  border-color: rgba(217, 119, 6, 0.3);
}

.mech-conf-col--high {
  border-color: rgba(5, 150, 105, 0.3);
}

.mech-conf-num.warn {
  color: var(--warning);
}

.mech-conf-caption {
  font-size: 11px;
  color: var(--text-secondary);
  display: block;
  margin-top: 6px;
}

.mech-conf-arrow {
  color: var(--text-muted);
  font-size: 18px;
  font-weight: 700;
}

.mech-conf-footnote {
  font-size: 11px;
  color: var(--text-secondary);
  text-align: center;
  margin-top: 10px;
  max-width: 480px;
}

.mech-improve-loop {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  margin-bottom: 10px;
}

.mech-loop-step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 12px;
  font-size: 11px;
}

.mech-loop-step--feat {
  border-color: rgba(37, 99, 235, 0.35);
  background: rgba(37, 99, 235, 0.04);
}

.mech-loop-arrow {
  color: var(--text-muted);
  font-size: 14px;
}

.mechanism.is-paused .mech-svg-line,
.mechanism.is-paused .mech-chip--float {
  animation-play-state: paused;
}

/* Delivery briefing — single coherent visual */
.delivery-briefing {
  max-width: 560px;
  margin: 0 auto;
  text-align: left;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 16px 40px rgba(17, 24, 39, 0.06);
}

.db-header {
  padding: 22px 24px 16px;
  border-bottom: 1px solid var(--border);
}

.db-eyebrow {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 10px;
}

.db-title-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.db-title-row h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 0;
}

.db-status {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.04em;
  padding: 5px 10px;
  border-radius: 999px;
  background: rgba(217, 119, 6, 0.1);
  color: var(--warning);
}

.db-metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--border);
  border-bottom: 1px solid var(--border);
}

.db-metric {
  background: var(--background);
  padding: 14px 12px;
  text-align: center;
}

.db-metric span {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.db-metric strong {
  font-size: 14px;
}

.db-metric--warn strong {
  color: var(--warning);
}

.db-evidence-block {
  padding: 18px 24px;
  border-bottom: 1px solid var(--border);
}

.db-evidence-label {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 12px;
}

.db-evidence-items {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.db-ev-item {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  padding: 10px 12px;
  background: var(--background);
  border: 1px solid var(--border);
  border-radius: 10px;
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.4s ease, transform 0.4s ease;
}

.delivery-briefing.is-revealed .db-ev-item,
.delivery-briefing.is-revealed .db-diagnosis,
.delivery-briefing.is-revealed .db-action-block {
  opacity: 1;
  transform: translateY(0);
}

.db-ev-src {
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  min-width: 72px;
}

.db-diagnosis {
  margin-top: 12px;
  padding: 12px;
  border-radius: 10px;
  background: rgba(217, 119, 6, 0.08);
  font-size: 12px;
  font-weight: 600;
  color: var(--warning);
  text-align: center;
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.4s ease 0.4s, transform 0.4s ease 0.4s;
}

.db-action-block {
  padding: 18px 24px 22px;
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.4s ease 0.5s, transform 0.4s ease 0.5s;
}

.db-action-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-size: 12px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}

.db-action-row:last-child {
  border-bottom: none;
}

.db-action-row span {
  color: var(--text-muted);
  font-weight: 600;
  font-size: 10px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.db-action-row strong {
  text-align: right;
  font-size: 13px;
}

.db-action-block.db-ev-reveal {
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.4s ease 0.5s, transform 0.4s ease 0.5s;
}

/* Data Trust prerequisite */
.trust-prerequisite {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px;
  max-width: 640px;
  margin: 0 auto 24px;
  padding: 16px;
  background: rgba(37, 99, 235, 0.04);
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: 12px;
}

.trust-pre-step {
  font-size: 12px;
  font-weight: 700;
  padding: 10px 16px;
  border-radius: 8px;
  background: var(--surface);
  border: 1px solid var(--border);
}

.trust-pre-step--feat {
  border-color: rgba(217, 119, 6, 0.35);
  background: rgba(217, 119, 6, 0.06);
  color: var(--warning);
}

/* Footer brand column */
.footer-col--brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.footer-col--brand > .brand-lockup {
  display: inline-flex;
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
  gap: 10px;
}

.footer-col--brand > .brand-lockup .brand-mark {
  background: var(--primary);
  color: #fff;
}

.footer-col--brand > .brand-lockup .brand-name {
  color: var(--primary);
}

.footer-col--brand .footer-tagline {
  margin-top: 12px;
  max-width: 240px;
}

@keyframes vizDash {
  to { stroke-dashoffset: -20; }
}

@media (prefers-reduced-motion: reduce) {
  .db-ev-item,
  .db-diagnosis,
  .db-action-block {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }

  .mech-svg-line {
    animation: none;
  }
}

@media (max-width: 1024px) {
  .mechanism-viewport {
    height: 380px;
  }
}

@media (max-width: 768px) {
  .mechanism-viewport {
    height: 360px;
    padding: 16px 18px 14px;
  }

  .db-metrics {
    grid-template-columns: repeat(2, 1fr);
  }

  .mech-conf-compare {
    grid-template-columns: 1fr;
  }

  .mech-conf-arrow {
    transform: rotate(90deg);
    text-align: center;
  }

  .mech-improve-loop {
    flex-direction: column;
  }

  .mech-action-grid {
    grid-template-columns: 1fr;
  }

  .mech-truth-grid {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .mech-qeai-row {
    grid-template-columns: 52px 1fr;
    gap: 8px;
    padding: 10px 12px;
  }
}

@media (max-width: 390px) {
  .mechanism-viewport {
    height: 340px;
    padding: 14px 14px 12px;
  }

  .mech-stage-btn {
    font-size: 9px;
    padding: 6px 10px;
  }
}

@keyframes mechFadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.mech-panel-title {
  flex: 0 0 auto;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
}

.mech-panel-desc {
  flex: 0 0 auto;
  min-height: 40px;
  font-size: 13px;
  color: var(--text-secondary);
  margin-top: 12px;
  margin-bottom: 0;
  line-height: 1.45;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.mech-panel-desc--reserve {
  visibility: hidden;
}

/* Stage 1 — scattered signals */
.mech-signals {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}

.mech-chip {
  font-size: 12px;
  font-weight: 600;
  padding: 10px 14px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--surface);
  animation: chipAppear 0.5s ease both;
}

.mech-chip:nth-child(1) { animation-delay: 0.05s; }
.mech-chip:nth-child(2) { animation-delay: 0.12s; }
.mech-chip:nth-child(3) { animation-delay: 0.19s; }
.mech-chip:nth-child(4) { animation-delay: 0.26s; }
.mech-chip:nth-child(5) { animation-delay: 0.33s; }
.mech-chip:nth-child(6) { animation-delay: 0.4s; }
.mech-chip:nth-child(7) { animation-delay: 0.47s; }

@keyframes chipAppear {
  from { opacity: 0; transform: scale(0.92); }
  to { opacity: 1; transform: scale(1); }
}

/* Stage 2 — normalized states */
.mech-states {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: 10px;
}

.mech-state {
  text-align: center;
  padding: 12px;
  border-radius: 10px;
  background: var(--surface);
  border: 1px solid var(--border);
  font-size: 12px;
  font-weight: 600;
}

.mech-state span {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 4px;
}

/* Stage 3 — relationships */
.mech-relate {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.mech-node {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 14px;
  font-size: 12px;
  font-weight: 600;
  text-align: center;
}

.mech-node small {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 2px;
}

.mech-edge {
  color: var(--accent);
  font-size: 16px;
  animation: edgePulse 1.2s ease infinite;
}

@keyframes edgePulse {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 1; }
}

/* Stage 4 — legacy row (unused) */
.mech-evidence-row {
  display: none;
}

.mech-ev-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 16px;
  font-size: 12px;
}

.mech-ev-item strong { display: block; font-size: 13px; margin-bottom: 2px; }

/* Stage 5 — truth */
.mech-truth-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.mech-truth-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 10px;
  text-align: center;
}

.mech-truth-item span {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.mech-truth-item strong { font-size: 1.125rem; }
.mech-truth-item strong.warn { color: var(--warning); }

/* Stage 6 — confidence */
.mech-conf-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.mech-conf-main {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  text-align: center;
}

.mech-conf-num {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
  margin: 6px 0;
}

.mech-conf-trust {
  background: rgba(217, 119, 6, 0.06);
  border: 1px solid rgba(217, 119, 6, 0.25);
  border-radius: 12px;
  padding: 20px;
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.5;
}

.mech-conf-trust strong { color: var(--warning); }

/* Stage 7 — intelligence */
.mech-canvas--confidence {
  flex-direction: column;
  gap: 4px;
}

.mech-qeai {
  display: flex;
  flex-direction: column;
  gap: 6px;
  width: 100%;
  max-width: 520px;
}

.mech-qeai-row {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 12px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 14px;
  align-items: start;
}

.mech-qeai-q {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--accent);
}

.mech-qeai-row strong { display: block; font-size: 13px; margin-bottom: 2px; }
.mech-qeai-row span { font-size: 12px; color: var(--text-secondary); }

/* Stage 8 — action */
.mech-action-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.mech-action-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px;
}

.mech-action-item--feat {
  border-color: rgba(37, 99, 235, 0.35);
  background: rgba(37, 99, 235, 0.04);
}

.mech-action-item span {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.mech-action-item strong { font-size: 13px; }

/* Stage 9 — improve */
.mech-improve {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.mech-improve-item {
  font-size: 14px;
  font-weight: 600;
  padding: 12px 18px;
  border-radius: 10px;
  background: rgba(5, 150, 105, 0.08);
  color: var(--success);
  border: 1px solid rgba(5, 150, 105, 0.25);
}

.mechanism-progress {
  height: 3px;
  background: var(--border);
  border-radius: 999px;
  margin-top: 16px;
  overflow: hidden;
}

.mechanism-progress-fill {
  height: 100%;
  background: var(--accent);
  border-radius: 999px;
  width: 11.11%;
  transition: width 0.4s ease;
}

.mechanism-controls {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-top: 16px;
}

.mech-control-btn {
  font: inherit;
  font-size: 12px;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  cursor: pointer;
  color: var(--text-secondary);
}

.mech-control-btn:hover,
.mech-control-btn:focus-visible {
  border-color: var(--accent);
  color: var(--accent);
  outline: none;
}

/* Reduced motion — same fixed canvas, no auto-advance */
.mechanism.is-reduced-motion .mech-panel {
  transition: opacity 0.15s ease, visibility 0.15s ease;
}

.mechanism.is-reduced-motion .mech-panel--enter .mech-chip--float,
.mechanism.is-reduced-motion .mech-panel--enter .mech-chain-link,
.mechanism.is-reduced-motion .mech-svg-line {
  animation: none;
}

/* Homepage navbar — transparent at top, hero background on scroll */
.page-home #site-nav {
  background: transparent;
  border-bottom: 1px solid transparent;
  box-shadow: none;
  transition: background-color 0.35s ease, border-color 0.35s ease, box-shadow 0.35s ease;
}

.page-home #site-nav.nav--hero-scrolled {
  background: var(--hero-bg);
  border-bottom-color: rgba(148, 163, 184, 0.12);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.18);
}

/* Shared brand lockup — navbar + footer */
.brand-lockup {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: inherit;
}

.trust-distinction {
  max-width: 640px;
  margin: -12px auto 24px;
  font-size: 13px;
  color: var(--text-secondary);
  text-align: center;
  line-height: 1.5;
}

/* ── §05 Briefing split ── */
.briefing-split {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 28px;
  align-items: start;
  text-align: left;
  max-width: var(--max);
  margin: 0 auto;
}

.briefing-evidence {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 22px;
}

.briefing-evidence h3 {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 14px;
}

.evidence-chain {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.evidence-link {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 12px;
  padding: 10px 12px;
  background: var(--background);
  border: 1px solid var(--border);
  border-radius: 10px;
}

.evidence-link .src {
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  min-width: 48px;
}

.evidence-conclusion {
  margin-top: 14px;
  padding: 12px;
  border-radius: 10px;
  background: rgba(217, 119, 6, 0.08);
  font-size: 12px;
  font-weight: 600;
  color: var(--warning);
  text-align: center;
}

/* ── §06 Data Trust pipeline ── */
.trust-pipeline {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px;
  max-width: 900px;
  margin: 0 auto 28px;
}

.trust-pipe-step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 14px;
  font-size: 11px;
  font-weight: 600;
  text-align: center;
  min-width: 90px;
}

.trust-pipe-step--feat {
  border-color: rgba(217, 119, 6, 0.35);
  background: rgba(217, 119, 6, 0.04);
}

.trust-pipe-arrow {
  color: var(--text-muted);
  font-size: 14px;
}

.trust-strip-v2 {
  max-width: 820px;
  margin: 0 auto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  overflow: hidden;
  text-align: left;
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 24px;
  padding: 24px 28px;
}

.trust-strip-v2 .trust-promise {
  grid-column: 1 / -1;
  text-align: left;
  max-width: none;
  font-size: 13px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
}

.trust-strip-v2 .trust-promise em {
  font-style: normal;
  font-weight: 600;
  color: var(--primary);
}

/* ── §07 Questions progression ── */
.questions-progress {
  max-width: 900px;
  margin: 0 auto;
}

.q-progress-rail {
  display: flex;
  align-items: stretch;
  gap: 0;
  position: relative;
  margin-bottom: 32px;
}

.q-progress-rail::before {
  content: "";
  position: absolute;
  top: 20px;
  left: 10%;
  right: 10%;
  height: 2px;
  background: var(--border);
  z-index: 0;
}

.q-progress-fill {
  position: absolute;
  top: 20px;
  left: 10%;
  height: 2px;
  background: var(--accent);
  z-index: 1;
  width: 0;
  transition: width 0.6s ease;
}

.q-step {
  flex: 1;
  text-align: center;
  position: relative;
  z-index: 2;
  padding: 0 8px;
  opacity: 0.45;
  transition: opacity 0.3s;
}

.q-step.active,
.q-step.done {
  opacity: 1;
}

.q-step-dot {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--surface);
  border: 2px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  font-weight: 700;
  margin: 0 auto 10px;
  color: var(--text-muted);
  transition: border-color 0.3s, background 0.3s, color 0.3s;
}

.q-step.active .q-step-dot,
.q-step.done .q-step-dot {
  border-color: var(--accent);
  background: rgba(37, 99, 235, 0.08);
  color: var(--accent);
}

.q-step.done .q-step-dot {
  background: var(--accent);
  color: #fff;
}

.q-step-label {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.q-step h3 {
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 4px;
}

.q-step p {
  font-size: 11px;
  color: var(--text-secondary);
  line-height: 1.4;
}

.q-step .badge { margin-top: 6px; }

/* ── §08 Diff stack (homepage) ── */
.hp-diff-stack {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  max-width: 640px;
  margin: 0 auto;
  text-align: center;
}

.hp-diff-col h4 {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 14px;
}

.hp-diff-step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 4px;
}

.hp-diff-step--muted { opacity: 0.6; }

.hp-diff-step--feat {
  border-color: rgba(37, 99, 235, 0.35);
  background: rgba(37, 99, 235, 0.04);
  color: var(--accent);
  font-size: 12px;
}

.hp-diff-arrow {
  color: var(--text-muted);
  font-size: 12px;
  padding: 2px 0;
}

.briefing-split .product-frame {
  margin: 0;
  max-width: none;
  box-shadow: 0 12px 32px rgba(17, 24, 39, 0.08);
}

.briefing-split .product-frame .app-shell {
  min-height: 360px;
}

.hero-problem {
  font-size: 1rem;
  color: var(--hero-muted);
  max-width: 560px;
  margin: 0 auto 8px;
  line-height: 1.5;
}

@media (max-width: 900px) {
  .gap-visual {
    grid-template-columns: 1fr;
  }

  .gap-arrow {
    transform: rotate(90deg);
  }

  .briefing-split {
    grid-template-columns: 1fr;
  }

  .mech-truth-grid,
  .mech-conf-row,
  .mech-action-grid,
  .hp-diff-stack {
    grid-template-columns: 1fr;
  }

  .q-progress-rail {
    flex-direction: column;
    gap: 20px;
  }

  .q-progress-rail::before,
  .q-progress-fill {
    display: none;
  }
}

@media (max-width: 768px) {
  .mechanism-rail {
    gap: 4px;
  }

  .mech-stage-btn {
    font-size: 9px;
    padding: 6px 8px;
  }

  .trust-strip-v2 {
    grid-template-columns: 1fr;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .mech-panel,
  .mech-chip,
  .mech-edge {
    animation: none;
  }

  .mechanism-progress-fill,
  .q-progress-fill {
    transition: none;
  }
}