.page-platform .hero {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  padding-top: var(--space-4);
  padding-bottom: var(--space-6);
}

.page-platform .hero__inner {
  display: block;
}

.page-platform .hero .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin: 0 0 var(--space-3);
  padding: 0;
  list-style: none;
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
}

.page-platform .hero .breadcrumb li {
  color: var(--color-contrast-ink);
  opacity: 0.7;
}

.page-platform .hero .breadcrumb li + li::before {
  content: "/ ";
  color: var(--color-contrast-line);
}

.page-platform .hero .breadcrumb a {
  color: var(--color-contrast-ink);
  text-decoration: none;
  border-bottom: 1px solid var(--color-contrast-line);
}

.page-platform .hero .breadcrumb a:hover,
.page-platform .hero .breadcrumb a:focus-visible {
  border-bottom-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
}

/* ---------- 首屏拼贴 ---------- */

.page-platform .hero-collage {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background-color: var(--color-contrast-line);
  border: 1px solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-platform .hero-main {
  position: relative;
  display: flex;
  align-items: flex-end;
  min-height: 340px;
  overflow: hidden;
  background-color: var(--color-contrast-surface);
}

.page-platform .hero-main__img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.page-platform .hero-main__scrim {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
}

.page-platform .hero-main__body {
  position: relative;
  z-index: 1;
  width: 100%;
  padding: var(--space-4) var(--space-3);
}

.page-platform .hero-eyebrow {
  margin: 0 0 var(--space-2);
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-contrast-accent);
}

.page-platform .hero-title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}

.page-platform .hero-lead {
  max-width: 48ch;
  margin: var(--space-2) 0 0;
  font-size: var(--text-base);
  line-height: 1.75;
  color: var(--color-contrast-ink);
  opacity: 0.86;
}

.page-platform .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-2);
  margin: var(--space-3) 0 0;
  padding-top: var(--space-3);
  border-top: 1px solid var(--color-contrast-line);
}

.page-platform .hero-stat {
  display: flex;
  flex-direction: column-reverse;
}

.page-platform .hero-stat dd {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin: 0;
  padding-bottom: 4px;
  border-bottom: 2px solid var(--color-contrast-accent);
}

.page-platform .hero-stat__num,
.page-platform .hero-stat__unit {
  font-family: var(--font-mono);
  font-size: var(--text-3xl);
  font-weight: 600;
  line-height: 1.1;
  color: var(--color-contrast-ink);
}

.page-platform .hero-stat__unit {
  font-size: var(--text-sm);
  opacity: 0.7;
}

.page-platform .hero-stat__label {
  margin-top: var(--space-1);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-contrast-ink);
  opacity: 0.62;
}

.page-platform .hero-cell {
  padding: var(--space-3);
  background-color: var(--color-contrast-surface);
}

.page-platform .hero-cell__label {
  margin: 0 0 var(--space-2);
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-contrast-accent);
}

.page-platform .hero-cell__text {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.8;
  color: var(--color-contrast-ink);
  opacity: 0.82;
}

.page-platform .hero-cell__list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--color-contrast-line);
}

.page-platform .hero-cell__list li {
  border-bottom: 1px solid var(--color-contrast-line);
}

.page-platform .hero-cell__link {
  display: block;
  padding: var(--space-2) 0;
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  text-decoration: none;
  border-left: 2px solid transparent;
  padding-left: var(--space-2);
  transition: border-color 160ms linear, color 160ms linear;
}

.page-platform .hero-cell__link:hover,
.page-platform .hero-cell__link:focus-visible {
  border-left-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
  outline: none;
}

/* ---------- 主体框架 ---------- */

.page-platform .layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-4);
  padding-top: var(--space-6);
  padding-bottom: var(--space-8);
}

.page-platform .lines {
  min-width: 0;
}

/* ---------- 章节头 ---------- */

.page-platform .line-section .chapter-head {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  column-gap: var(--space-2);
  align-items: start;
  padding-bottom: var(--space-3);
  border-bottom: 1px solid var(--color-line);
}

.page-platform .line-section .chapter-head__no {
  grid-column: 1;
  grid-row: 1 / span 4;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 32px;
  padding: 4px 0;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-primary-ink);
  background-color: var(--color-primary);
  border-radius: var(--radius-sm);
}

.page-platform .line-section .chapter-head__eyebrow {
  grid-column: 2;
  margin: 0 0 var(--space-1);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-primary);
}

.page-platform .line-section .chapter-head__title {
  grid-column: 2;
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  color: var(--color-ink);
}

.page-platform .line-section .chapter-head__lead {
  grid-column: 2;
  max-width: var(--measure);
  margin: var(--space-2) 0 0;
  font-size: var(--text-base);
  line-height: 1.8;
  color: var(--color-ink-soft);
}

/* ---------- 章节本体 ---------- */

.page-platform .line-section {
  padding-bottom: var(--space-6);
  margin-bottom: var(--space-6);
  border-bottom: 1px solid var(--color-line);
}

.page-platform .line-section--last {
  border-bottom: 0;
}

.page-platform .line-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-3);
  padding-top: var(--space-3);
}

.page-platform .line-figure {
  margin: 0;
  border: 1px solid var(--color-line);
  background-color: var(--color-surface-alt);
}

.page-platform .line-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-platform .line-figure__cap {
  margin: 0;
  padding: var(--space-1) var(--space-2);
  font-family: var(--font-heading);
  font-style: italic;
  font-size: var(--text-xs);
  line-height: 1.7;
  color: var(--color-ink-muted);
  border-top: 1px solid var(--color-line);
}

.page-platform .line-fields {
  margin: 0;
  border-top: 1px solid var(--color-line);
}

.page-platform .line-field {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-line);
}

.page-platform .line-field dt {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--color-primary);
}

.page-platform .line-field dd {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.85;
  color: var(--color-ink);
}

.page-platform .line-section .note {
  margin-top: var(--space-3);
}

.page-platform .line-section .note__title {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.page-platform .line-section .note__body {
  font-size: var(--text-sm);
  line-height: 1.85;
}

/* ---------- 协同顺序 ---------- */

.page-platform .synergy-steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin: var(--space-4) 0 0;
  padding: 0;
  list-style: none;
  background-color: var(--color-line);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-platform .synergy-step {
  background-color: var(--color-surface);
}

.page-platform .synergy-step__link {
  display: block;
  height: 100%;
  padding: var(--space-3);
  text-decoration: none;
  border-top: 3px solid var(--color-primary);
  transition: background-color 160ms linear, border-color 160ms linear;
}

.page-platform .synergy-step__link:hover,
.page-platform .synergy-step__link:focus-visible {
  background-color: var(--color-primary-soft);
  border-top-color: var(--color-accent);
  outline: none;
}

.page-platform .synergy-step__no {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-accent);
  margin-bottom: var(--space-1);
}

.page-platform .synergy-step__title {
  display: block;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: 1.4;
  color: var(--color-ink);
}

.page-platform .synergy-step__desc {
  display: block;
  margin-top: var(--space-1);
  font-size: var(--text-sm);
  line-height: 1.8;
  color: var(--color-ink-soft);
}

/* ---------- 延伸入口 ---------- */

.page-platform .follow {
  margin-top: var(--space-4);
  padding: var(--space-3);
  background-color: var(--color-surface-alt);
  border: 1px solid var(--color-line);
  border-left: 3px solid var(--color-primary);
  border-radius: var(--radius-sm);
}

.page-platform .follow__lead {
  margin: 0 0 var(--space-2);
  font-size: var(--text-base);
  line-height: 1.8;
  color: var(--color-ink);
}

.page-platform .follow__list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--color-line);
}

.page-platform .follow__item {
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-line);
}

.page-platform .follow__link {
  display: inline-block;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  color: var(--color-primary);
  text-decoration: none;
  border-bottom: 2px solid var(--color-primary-soft);
}

.page-platform .follow__link:hover,
.page-platform .follow__link:focus-visible {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
  outline: none;
}

.page-platform .follow__desc {
  display: block;
  margin-top: 4px;
  font-size: var(--text-sm);
  line-height: 1.8;
  color: var(--color-ink-soft);
}

/* ---------- 出口 ---------- */

.page-platform .exit {
  margin-top: var(--space-4);
  padding: var(--space-4) var(--space-3);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-radius: var(--radius-sm);
}

.page-platform .exit__label {
  margin: 0 0 var(--space-2);
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-contrast-accent);
}

.page-platform .exit__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  color: var(--color-contrast-ink);
}

.page-platform .exit__text {
  max-width: var(--measure);
  margin: var(--space-2) 0 0;
  font-size: var(--text-base);
  line-height: 1.85;
  color: var(--color-contrast-ink);
  opacity: 0.84;
}

.page-platform .exit__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

/* ---------- 中屏 ---------- */

@media (min-width: 640px) {
  .page-platform .hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-platform .line-field {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: var(--space-2);
  }

  .page-platform .line-field dt {
    padding-top: 3px;
  }

  .page-platform .hero-cell__list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-platform .hero-cell__list li:nth-child(odd) {
    border-right: 1px solid var(--color-contrast-line);
  }

  .page-platform .hero-cell__list li:nth-child(odd) .hero-cell__link {
    padding-right: var(--space-2);
  }
}

/* ---------- 桌面 ---------- */

@media (min-width: 1000px) {
  .page-platform .hero {
    padding-top: var(--space-6);
  }

  .page-platform .hero-collage {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    grid-template-rows: auto auto auto;
  }

  .page-platform .hero-main {
    grid-column: 1 / 3;
    grid-row: 1 / 3;
    min-height: 520px;
  }

  .page-platform .hero-main__body {
    padding: var(--space-6) var(--space-4);
  }

  .page-platform .hero-cell--a {
    grid-column: 3;
    grid-row: 1;
  }

  .page-platform .hero-cell--b {
    grid-column: 3;
    grid-row: 2;
  }

  .page-platform .hero-cell--c {
    grid-column: 1 / 4;
    grid-row: 3;
  }

  .page-platform .layout {
    grid-template-columns: 186px minmax(0, 1fr);
    gap: var(--space-6);
    padding-top: var(--section-y);
  }

  .page-platform .toc {
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-platform .line-body {
    gap: var(--space-4);
  }

  .page-platform .line-section--img-left .line-body {
    grid-template-columns: 5fr 7fr;
  }

  .page-platform .line-section--img-right .line-body {
    grid-template-columns: 7fr 5fr;
  }

  .page-platform .line-section--img-right .line-figure {
    order: 2;
  }

  .page-platform .line-section--img-mid .line-body {
    grid-template-columns: 7fr 4fr;
    align-items: start;
  }

  .page-platform .line-figure--offset {
    margin-top: var(--space-3);
  }

  .page-platform .synergy-steps {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-platform .synergy-step__link {
    padding: var(--space-3) var(--space-2);
  }

  .page-platform .follow__list {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    border-top: 0;
    gap: var(--space-3);
  }

  .page-platform .follow__item {
    padding: 0;
    border-bottom: 0;
    border-top: 2px solid var(--color-primary);
    padding-top: var(--space-2);
  }

  .page-platform .exit {
    padding: var(--space-6) var(--space-4);
  }
}

@media (min-width: 1080px) {
  .page-platform .line-section .chapter-head {
    grid-template-columns: 52px minmax(0, 1fr);
    column-gap: var(--space-3);
  }
}
<<<END>>>