.page-platform {
  --platform-shell-cols: 1fr;
  --platform-nav-w: 232px;
  --platform-gap: var(--space-4);
}

/* ============ 首屏框景 ============ */
.page-platform .hero-frame {
  background: var(--color-surface);
}

.page-platform .hero-frame__inner {
  border: var(--border-thick) solid var(--color-line);
  padding: var(--space-4) var(--space-3);
  position: relative;
}

.page-platform .hero-frame__inner::before {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 6px;
  background: var(--color-primary);
}

.page-platform .hero-frame__title {
  margin: var(--space-2) 0 var(--space-3);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-platform .hero-frame__lede {
  max-width: var(--measure);
  color: var(--color-ink-soft);
  line-height: var(--leading-body);
  font-size: var(--text-base);
  margin-bottom: var(--space-6);
}

.page-platform .hero-frame__body {
  display: grid;
  gap: var(--space-6);
}

.page-platform .hero-frame__digits {
  display: grid;
  gap: var(--space-3);
}

.page-platform .digit-row {
  display: grid;
  grid-template-columns: minmax(0, auto) 1fr;
  align-items: baseline;
  gap: var(--space-3);
  border-bottom: var(--border-thin) solid var(--color-line);
  padding-bottom: var(--space-2);
}

.page-platform .digit-row__value {
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  font-weight: var(--weight-heading);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--color-ink);
}

.page-platform .digit-row__meta {
  display: grid;
  gap: 2px;
}

.page-platform .digit-row__unit {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  color: var(--color-primary);
}

.page-platform .digit-row__note {
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
  line-height: 1.6;
}

.page-platform .hero-frame__visual {
  display: grid;
  gap: var(--space-3);
  align-items: end;
}

.page-platform .dial-wrap {
  position: relative;
  width: 100%;
  max-width: 340px;
  margin: 0 auto;
  aspect-ratio: 1 / 1;
}

.page-platform .dial {
  width: 100%;
  height: 100%;
  display: block;
  transform: rotate(0deg);
}

.page-platform .dial__track {
  stroke: var(--color-surface-deep);
  stroke-width: 26;
}

.page-platform .dial__arc {
  stroke-width: 26;
  stroke-linecap: butt;
  transition: stroke-width 200ms ease-out;
}

.page-platform .dial__arc--coverage {
  stroke: var(--color-primary);
}

.page-platform .dial__arc--schedule {
  stroke: var(--color-accent);
}

.page-platform .dial__arc--scope {
  stroke: var(--color-contrast-surface);
}

.page-platform .dial__arc--version {
  stroke: color-mix(in srgb, var(--color-primary) 48%, var(--color-surface));
}

.page-platform .dial__center {
  position: absolute;
  inset: 34%;
  display: grid;
  place-content: center;
  gap: var(--space-1);
  text-align: center;
}

.page-platform .dial__center .version-chip {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  color: var(--color-ink);
  letter-spacing: -0.02em;
}

.page-platform .dial__center-label {
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  letter-spacing: 0.04em;
}

.page-platform .hero-frame__figure {
  border: var(--border-thin) solid var(--color-line);
  background: var(--color-surface-alt);
  padding: var(--space-1);
}

/* ============ 主体 + 侧栏 ============ */
.page-platform .platform-shell {
  display: grid;
  grid-template-columns: var(--platform-shell-cols);
  gap: var(--platform-gap);
  align-items: start;
}

.page-platform .platform-toc {
  border: var(--border-thin) solid var(--color-line);
  padding: var(--space-3);
  background: var(--color-surface-alt);
}

.page-platform .platform-toc .toc__title {
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
  margin-bottom: var(--space-2);
}

.page-platform .platform-toc ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
  counter-reset: tocidx;
}

.page-platform .platform-toc li {
  counter-increment: tocidx;
}

.page-platform .platform-toc a {
  display: block;
  padding: var(--space-1) var(--space-2) var(--space-1) calc(var(--space-4) + 4px);
  position: relative;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  color: var(--color-ink);
  text-decoration: none;
  border-left: var(--border-thick) solid transparent;
  transition: background-color 180ms ease-out, border-color 180ms ease-out, color 180ms ease-out;
}

.page-platform .platform-toc a::before {
  content: counter(tocidx, decimal-leading-zero);
  position: absolute;
  left: var(--space-2);
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.page-platform .platform-toc a:hover,
.page-platform .platform-toc a:focus-visible {
  background: var(--color-primary-soft);
  border-left-color: var(--color-primary);
}

.page-platform .platform-toc__foot {
  margin-top: var(--space-3);
  padding-top: var(--space-2);
  border-top: var(--border-thin) solid var(--color-line);
  display: grid;
  gap: var(--space-1);
}

.page-platform .platform-toc__quick {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  text-decoration: none;
  border-bottom: 1px solid var(--color-line);
  padding-bottom: 2px;
}

.page-platform .platform-toc__quick:hover,
.page-platform .platform-toc__quick:focus-visible {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}

.page-platform .platform-flow {
  display: grid;
  gap: var(--space-8);
  min-width: 0;
}

/* ============ 分类区块 ============ */
.page-platform .category {
  display: grid;
  gap: var(--space-4);
}

.page-platform .category__head {
  display: grid;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  border-left: 6px solid var(--cat-color, var(--color-primary));
  background: var(--cat-bg, var(--color-surface-alt));
}

.page-platform .category__index {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  color: var(--cat-color, var(--color-primary));
  letter-spacing: 0.14em;
}

.page-platform .category__title {
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-platform .category__sub {
  max-width: var(--measure);
  font-size: var(--text-base);
  color: var(--color-ink-soft);
  line-height: 1.7;
  margin-top: var(--space-1);
}

.page-platform .category--coverage {
  --cat-color: var(--color-primary);
  --cat-bg: var(--color-primary-soft);
}

.page-platform .category--schedule {
  --cat-color: var(--color-accent);
  --cat-bg: var(--color-highlight);
}

.page-platform .category--scope {
  --cat-color: var(--color-contrast-surface);
  --cat-bg: var(--color-surface-deep);
}

.page-platform .category--version {
  --cat-color: color-mix(in srgb, var(--color-primary) 55%, var(--color-contrast-surface));
  --cat-bg: var(--color-surface-alt);
}

.page-platform .category__body {
  display: grid;
  gap: var(--space-4);
}

.page-platform .category__figure {
  border: var(--border-thin) solid var(--color-line);
  background: var(--color-surface-alt);
  padding: var(--space-2);
}

.page-platform .category__figure--lead {
  order: -1;
}

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

.page-platform .metric {
  border: var(--border-thin) solid var(--color-line);
  background: var(--color-surface);
  padding: var(--space-3);
  display: grid;
  gap: var(--space-2);
  align-content: start;
  transition: border-color 180ms ease-out;
}

.page-platform .metric.is-open {
  border-color: var(--color-focus);
}

.page-platform .metric__score {
  display: flex;
  align-items: baseline;
  gap: var(--space-1);
  border-bottom: var(--border-thin) solid var(--color-line);
  padding-bottom: var(--space-2);
}

.page-platform .metric__value {
  font-family: var(--font-mono);
  font-size: var(--text-3xl);
  font-weight: var(--weight-heading);
  line-height: 0.95;
  letter-spacing: -0.035em;
  color: var(--color-ink);
}

.page-platform .metric__unit {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  color: var(--cat-color, var(--color-primary));
}

.page-platform .metric__name {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: 1.3;
  color: var(--color-ink);
}

.page-platform .metric__scope {
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
  line-height: 1.72;
  padding-left: var(--space-2);
  border-left: 2px solid var(--color-line);
}

.page-platform .metric__trigger {
  justify-self: start;
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  color: var(--color-ink-soft);
  background: none;
  border: none;
  padding: 0;
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  cursor: pointer;
  transition: color 180ms ease-out;
}

.page-platform .metric__trigger:hover,
.page-platform .metric__trigger:focus-visible {
  color: var(--color-focus);
}

.page-platform .metric__trigger .disclosure__marker {
  width: 10px;
  height: 10px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
  transition: transform 200ms ease-out;
  display: inline-block;
}

.page-platform .metric__trigger[aria-expanded="true"] .disclosure__marker {
  transform: rotate(-135deg);
}

.page-platform .metric__panel {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  line-height: 1.76;
  padding: var(--space-2) var(--space-3);
  background: var(--color-surface-alt);
  border-left: var(--border-thick) solid var(--color-focus);
}

.page-platform .metric__panel a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-platform .metric__panel a:hover,
.page-platform .metric__panel a:focus-visible {
  color: var(--color-focus);
}

/* ============ 校验关系 ============ */
.page-platform .relationships {
  border: var(--border-thick) solid var(--color-contrast-line);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  padding: var(--space-4) var(--space-3);
  display: grid;
  gap: var(--space-3);
}

.page-platform .relationships .eyebrow--contrast {
  color: var(--color-contrast-accent);
}

.page-platform .relationships__title {
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}

.page-platform .relationships__lede {
  max-width: var(--measure);
  color: var(--color-contrast-ink);
  opacity: 0.82;
  font-size: var(--text-base);
  line-height: 1.72;
}

.page-platform .relationships__body {
  display: grid;
  gap: var(--space-2);
  border-top: 1px solid var(--color-contrast-line);
  padding-top: var(--space-3);
}

.page-platform .rel-row {
  display: grid;
  grid-template-columns: minmax(0, auto) 1fr;
  gap: var(--space-3);
  align-items: start;
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-contrast-line);
}

.page-platform .rel-row__key {
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  font-weight: var(--weight-heading);
  color: var(--color-contrast-accent);
  line-height: 1;
  letter-spacing: -0.02em;
}

.page-platform .rel-row__text h3 {
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  color: var(--color-contrast-ink);
  margin-bottom: var(--space-1);
}

.page-platform .rel-row__text p {
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  opacity: 0.78;
  line-height: 1.72;
}

.page-platform .relationships__trigger {
  justify-self: start;
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  color: var(--color-contrast-accent);
  background: none;
  border: none;
  padding: 0;
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  cursor: pointer;
}

.page-platform .relationships__trigger .disclosure__marker {
  width: 10px;
  height: 10px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
  display: inline-block;
  transition: transform 200ms ease-out;
}

.page-platform .relationships__trigger[aria-expanded="true"] .disclosure__marker {
  transform: rotate(-135deg);
}

.page-platform .relationships__panel {
  font-size: var(--text-sm);
  line-height: 1.78;
  color: var(--color-contrast-ink);
  background: rgba(255, 255, 255, 0.05);
  border-left: var(--border-thick) solid var(--color-contrast-accent);
  padding: var(--space-2) var(--space-3);
}

.page-platform .relationships__panel a {
  color: var(--color-contrast-accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-platform .relationships__paths {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  border-top: 1px solid var(--color-contrast-line);
  padding-top: var(--space-3);
}

/* ============ 断点 ============ */
@media (min-width: 720px) {
  .page-platform .hero-frame__inner {
    padding: var(--space-6) var(--space-4);
  }

  .page-platform .hero-frame__body {
    grid-template-columns: 1.05fr 0.95fr;
    align-items: center;
    gap: var(--space-6);
  }

  .page-platform .hero-frame__visual {
    grid-template-columns: 1.35fr 1fr;
  }

  .page-platform .dial-wrap {
    max-width: 100%;
  }

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

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

  .page-platform .category__body--split {
    grid-template-columns: 1.6fr 1fr;
    align-items: start;
  }

  .page-platform .category__figure--narrow .figure__media--tall {
    aspect-ratio: 4 / 5;
  }
}

@media (min-width: 1024px) {
  .page-platform .platform-shell {
    grid-template-columns: var(--platform-nav-w) minmax(0, 1fr);
    gap: var(--space-6);
  }

  .page-platform .platform-toc {
    position: sticky;
    top: calc(var(--space-8) + var(--space-2));
  }

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

  .page-platform .metric-grid--wide {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-platform .metric--wide .metric__value {
    font-size: var(--text-4xl);
  }

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

@media (max-width: 380px) {
  .page-platform .digit-row {
    grid-template-columns: 1fr;
    gap: var(--space-1);
  }

  .page-platform .rel-row {
    grid-template-columns: 1fr;
    gap: var(--space-1);
  }
}
</style>