/* ============================================================
   S10 — Proof Page (/proof)
   Loaded as: css/proof.css
   Covers: P1 Header, P2 Deltas, P3 Methodology, P4 Cases,
           P5 Interpretation, P6 Routing
   Palette: locked — #40045D canonical purple | #000000 | #FFFFFF
            #C9A227 gold (secondary) | #0B0B0D | #161418
   Typography: Playfair Display 700 (display) / DM Sans 400/600/700
   ============================================================ */


/* ============================================================
   ACTIVE NAV STATE
   ============================================================ */

.site-nav__link--active {
  color: #FFFFFF;
  position: relative;
}

.site-nav__link--active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 1px;
  background-color: #C9A227;
}


/* ============================================================
   P1 — PAGE HEADER
   ============================================================ */

.proof-header {
  background: linear-gradient(160deg, #2C0442 0%, #14021F 52%, #0B0B0D 100%);
  padding: 120px 0 96px;
  border-bottom: 1px solid rgba(64, 4, 93, 0.35);
}

.proof-header__inner {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 40px;
}

.proof-header__eyebrow {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #C9A227;
  margin: 0 0 24px;
}

.proof-header__h1 {
  font-family: 'League Spartan', 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: clamp(2.25rem, 5vw, 3.5rem);
  color: #FFFFFF;
  line-height: 1.15;
  margin: 0 0 28px;
  letter-spacing: -0.01em;
}

.proof-header__intro {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 1.0625rem;
  color: rgba(255, 255, 255, 0.72);
  line-height: 1.75;
  margin: 0 0 20px;
}

.proof-header__distinction {
  font-family: 'DM Sans', sans-serif;
  font-weight: 600;
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.55);
  line-height: 1.65;
  margin: 0;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}


/* ============================================================
   P2 — AGGREGATE DELTA SUMMARY
   ============================================================ */

.proof-deltas {
  background-color: #0E0115;
  padding: 96px 0;
}

.proof-deltas__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
}

.proof-deltas__label {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #C9A227;
  margin: 0 0 40px;
}

.proof-deltas__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2px;
  margin-bottom: 48px;
}

.proof-deltas__delta {
  background-color: #14021F;
  padding: 40px 32px 44px;
  border-top: 2px solid rgba(64, 4, 93, 0.5);
  transition: border-top-color 0.25s ease;
}

.proof-deltas__delta:hover {
  border-top-color: #40045D;
}

.proof-deltas__figure {
  display: block;
  font-family: 'League Spartan', 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: clamp(2.5rem, 4vw, 3.5rem);
  color: #C9A227;
  line-height: 1;
  margin-bottom: 12px;
}

.proof-deltas__metric {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.875rem;
  color: #FFFFFF;
  margin: 0 0 12px;
  letter-spacing: 0.02em;
}

.proof-deltas__detail {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.5);
  line-height: 1.65;
  margin: 0;
}

.proof-deltas__footnote {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.55);
  line-height: 1.75;
  margin: 0;
  padding: 32px 0 0;
  border-top: 1px solid rgba(255, 255, 255, 0.07);
  max-width: 720px;
}


/* ============================================================
   P3 — METHODOLOGY NOTE
   ============================================================ */

.proof-methodology {
  background-color: #1B0328;
  padding: 80px 0;
  border-top: 1px solid rgba(64, 4, 93, 0.2);
  border-bottom: 1px solid rgba(64, 4, 93, 0.2);
}

.proof-methodology__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
  display: grid;
  grid-template-columns: 1fr 1px 1fr;
  gap: 56px;
  align-items: start;
}

.proof-methodology__heading {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.4);
  margin: 0 0 24px;
}

.proof-methodology__list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0;
  margin: 0;
  padding: 0;
}

.proof-methodology__list li {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.65);
  line-height: 1.65;
  padding: 14px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  padding-left: 16px;
  border-left: 2px solid rgba(64, 4, 93, 0.4);
  margin-bottom: 8px;
}

.proof-methodology__list--contrast li {
  border-left-color: rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.45);
}

.proof-methodology__divider {
  background: rgba(64, 4, 93, 0.3);
  align-self: stretch;
}

.proof-methodology__note {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.4);
  line-height: 1.7;
  margin: 24px 0 0;
  font-style: italic;
}


/* ============================================================
   P4 — CASE STUDIES
   ============================================================ */

.proof-cases {
  background-color: #14021F;
  padding: 96px 0;
}

.proof-cases__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
}

.proof-cases__label {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #C9A227;
  margin: 0 0 12px;
}

.proof-cases__intro {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 1rem;
  color: rgba(255, 255, 255, 0.5);
  margin: 0 0 64px;
  line-height: 1.6;
}

/* Individual case */
.proof-case {
  margin-bottom: 0;
}

.proof-case__rule {
  height: 1px;
  background: rgba(64, 4, 93, 0.25);
  margin: 56px 0;
}

.proof-case__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 36px;
}

.proof-case__id {
  display: flex;
  align-items: flex-start;
  gap: 20px;
}

.proof-case__num {
  font-family: 'League Spartan', 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 2.5rem;
  color: rgba(64, 4, 93, 0.35);
  line-height: 1;
  flex-shrink: 0;
  padding-top: 2px;
}

.proof-case__name {
  font-family: 'League Spartan', 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 1.5rem;
  color: #FFFFFF;
  margin: 0 0 4px;
  line-height: 1.2;
}

.proof-case__handle {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.35);
  letter-spacing: 0.04em;
  margin: 0;
}

.proof-case__run {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.35);
  letter-spacing: 0.04em;
  text-align: right;
  flex-shrink: 0;
  padding-top: 4px;
}

/* Case body — metrics + narrative */
.proof-case__body {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}

/* Metrics table */
.proof-case__metrics {
  background-color: #1B0328;
  padding: 32px 28px 36px;
}

.proof-case__metrics-label {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.3);
  margin: 0 0 20px;
}

.proof-case__metric-row {
  display: grid;
  grid-template-columns: 1fr auto auto;
  gap: 12px;
  align-items: center;
  padding: 12px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.proof-case__metric-row:last-child {
  border-bottom: none;
}

.proof-case__metric-row--highlight {
  background: rgba(64, 4, 93, 0.2);
  margin: 0 -28px;
  padding: 12px 28px;
  border-bottom: none;
  border-top: none;
}

.proof-case__metric-name {
  font-family: 'DM Sans', sans-serif;
  font-weight: 600;
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.65);
}

.proof-case__metric-values {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.875rem;
  color: #FFFFFF;
  white-space: nowrap;
}

.proof-case__metric-row--highlight .proof-case__metric-values {
  color: #C9A227;
}

.proof-case__arrow {
  color: rgba(255, 255, 255, 0.3);
  font-weight: 400;
  margin: 0 4px;
}

.proof-case__metric-delta {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.75rem;
  color: #C9A227;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.proof-case__metric-note {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.25);
  white-space: nowrap;
}

/* Narrative column */
.proof-case__narrative {
  display: flex;
  flex-direction: column;
  gap: 24px;
  padding-top: 4px;
}

.proof-case__condition {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.6);
  line-height: 1.75;
  margin: 0;
}

.proof-case__voice {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 1.0625rem;
  color: rgba(255, 255, 255, 0.85);
  line-height: 1.65;
  font-style: italic;
  margin: 0;
  padding-left: 20px;
  border-left: 3px solid #40045D;
}

.proof-case__permission {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.25);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin: 0;
}


/* ============================================================
   P5 — INTERPRETATION
   ============================================================ */

.proof-interpretation {
  background-color: #240436;
  padding: 96px 0;
  border-top: 1px solid rgba(64, 4, 93, 0.2);
}

.proof-interpretation__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 80px;
  align-items: start;
}

.proof-interpretation__heading {
  font-family: 'League Spartan', 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  color: #FFFFFF;
  line-height: 1.2;
  margin: 0;
}

.proof-interpretation__body {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.proof-interpretation__body p {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 1rem;
  color: rgba(255, 255, 255, 0.65);
  line-height: 1.8;
  margin: 0;
}

.proof-interpretation__body p:last-child {
  font-weight: 600;
  color: rgba(255, 255, 255, 0.85);
}


/* ============================================================
   P6 — ROUTING
   ============================================================ */

.proof-routing {
  background-color: #0E0115;
  padding: 96px 0 112px;
}

.proof-routing__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
}

.proof-routing__label {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #C9A227;
  margin: 0 0 16px;
}

.proof-routing__heading {
  font-family: 'League Spartan', 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  color: #FFFFFF;
  line-height: 1.2;
  margin: 0 0 56px;
}

.proof-routing__cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2px;
}

.proof-routing__card {
  display: flex;
  flex-direction: column;
  gap: 16px;
  background-color: #1B0328;
  padding: 40px 36px 44px;
  text-decoration: none;
  border: 1px solid rgba(255, 255, 255, 0.05);
  transition: border-color 0.25s ease, background-color 0.25s ease;
}

.proof-routing__card:hover {
  border-color: rgba(64, 4, 93, 0.4);
  background-color: #240436;
}

.proof-routing__card--primary {
  background-color: #40045D;
  border-color: rgba(64, 4, 93, 0.6);
}

.proof-routing__card--primary:hover {
  background-color: #5A0882;
  border-color: rgba(64, 4, 93, 0.9);
}

.proof-routing__card-label {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #C9A227;
  margin: 0;
}

.proof-routing__card-body {
  font-family: 'DM Sans', sans-serif;
  font-weight: 400;
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.65);
  line-height: 1.7;
  margin: 0;
  flex-grow: 1;
}

.proof-routing__card--primary .proof-routing__card-body {
  color: rgba(255, 255, 255, 0.8);
}

.proof-routing__card-link {
  font-family: 'DM Sans', sans-serif;
  font-weight: 700;
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  color: #C9A227;
  transition: letter-spacing 0.2s ease;
}

.proof-routing__card:hover .proof-routing__card-link {
  letter-spacing: 0.1em;
}


/* ============================================================
   RESPONSIVE — MOBILE PARITY
   Breakpoint: 768px
   ============================================================ */

@media (max-width: 768px) {

  .proof-header {
    padding: 96px 0 72px;
  }

  .proof-header__inner {
    padding: 0 24px;
  }

  .proof-deltas {
    padding: 72px 0;
  }

  .proof-deltas__inner {
    padding: 0 24px;
  }

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

  .proof-methodology {
    padding: 64px 0;
  }

  .proof-methodology__inner {
    padding: 0 24px;
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .proof-methodology__divider {
    display: none;
  }

  .proof-cases {
    padding: 72px 0;
  }

  .proof-cases__inner {
    padding: 0 24px;
  }

  .proof-case__header {
    flex-direction: column;
    gap: 12px;
  }

  .proof-case__run {
    text-align: left;
  }

  .proof-case__body {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .proof-interpretation {
    padding: 72px 0;
  }

  .proof-interpretation__inner {
    padding: 0 24px;
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .proof-routing {
    padding: 72px 0 88px;
  }

  .proof-routing__inner {
    padding: 0 24px;
  }

  .proof-routing__cards {
    grid-template-columns: 1fr;
    gap: 2px;
  }

}

/* Intermediate breakpoint — tablet layout relief */
@media (max-width: 1024px) and (min-width: 769px) {

  .proof-methodology__inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .proof-methodology__divider {
    display: none;
  }

  .proof-case__body {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .proof-interpretation__inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .proof-routing__cards {
    grid-template-columns: 1fr;
    gap: 2px;
  }

}


.proof-deltas__bridge,
.proof-case__meaning {
  margin-top: 18px;
  font-family: 'DM Sans', sans-serif;
  font-size: 0.95rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.72);
}

.proof-visitor-bridge {
  background: #0B0B0D;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.proof-visitor-bridge__inner {
  max-width: 860px;
  margin: 0 auto;
  padding: 72px 24px;
}

.proof-visitor-bridge__inner p {
  margin: 0 0 18px;
  font-family: 'DM Sans', sans-serif;
  font-size: 1.05rem;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.76);
}

.proof-visitor-bridge__inner p:last-child {
  margin-bottom: 0;
}