.page-features {
  background: var(--color-surface);
  color: var(--color-ink);
}

/* ---------- 首屏 ---------- */

.page-features .feat-hero {
  padding-top: var(--space-3);
  padding-bottom: var(--space-4);
}

.page-features .feat-hero .breadcrumb {
  margin-bottom: var(--space-3);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
}

.page-features .feat-hero__pulse {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  border-radius: var(--radius-sm);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  box-shadow: var(--shadow-2);
}

.page-features .feat-hero__texture {
  position: absolute;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.7;
}

.page-features .feat-hero__veil {
  position: absolute;
  inset: 0;
  z-index: 1;
  background: var(--overlay-scrim);
}

.page-features .feat-hero__inner {
  position: relative;
  z-index: 2;
  padding: var(--space-4) var(--space-3) var(--space-4);
}

.page-features .feat-hero__inner .kicker {
  color: var(--color-contrast-accent);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  margin: 0;
}

.page-features .feat-hero h1 {
  margin: var(--space-2) 0 var(--space-3);
  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);
  max-width: 16ch;
  text-wrap: balance;
}

.page-features .feat-hero__lead {
  margin: 0;
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-contrast-ink);
  opacity: 0.86;
}

.page-features .feat-wall {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-3) var(--space-2);
  margin-top: var(--space-4);
}

.page-features .feat-wall__cell {
  min-width: 0;
  padding-top: var(--space-2);
  border-top: 1px dashed var(--color-contrast-line);
}

.page-features .feat-wall__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  font-weight: var(--weight-heading);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--color-contrast-accent);
  overflow-wrap: anywhere;
}

.page-features .feat-wall__cap {
  margin: var(--space-1) 0 0;
  font-family: var(--font-body);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-contrast-ink);
  opacity: 0.74;
}

.page-features .feat-hero__footnote {
  margin: var(--space-4) 0 0;
  padding-top: var(--space-2);
  border-top: 1px dashed var(--color-contrast-line);
  max-width: var(--measure);
  font-size: var(--text-xs);
  line-height: var(--leading-body);
  letter-spacing: 0.03em;
  color: var(--color-contrast-ink);
  opacity: 0.68;
}

/* ---------- 分类索引尺 ---------- */

.page-features .feat-index {
  padding-bottom: var(--space-2);
}

.page-features .feat-index__list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-features .feat-index__link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  min-height: 44px;
  padding: 0 var(--space-2);
  border-radius: var(--radius-sm);
  background: var(--color-primary-soft);
  color: var(--color-ink);
  font-size: var(--text-sm);
  text-decoration: none;
  box-shadow: var(--shadow-1);
  transition: background-color 150ms ease, transform 150ms ease, box-shadow 150ms ease;
}

.page-features .feat-index__link:hover {
  background: var(--color-highlight);
  transform: translateY(calc(var(--space-1) * -0.25));
  box-shadow: var(--shadow-2);
}

.page-features .feat-index__link:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 2px;
}

.page-features .feat-index__count {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  line-height: 1.6;
  padding: 0 var(--space-1);
  border-radius: var(--radius-sm);
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

/* ---------- 分组骨架 ---------- */

.page-features .feat-group {
  padding: var(--space-4) 0 var(--space-6);
}

.page-features .feat-rule {
  height: var(--space-1);
  margin-bottom: var(--space-3);
  border: 0;
  border-top: 1px dashed var(--color-line);
  background-image: repeating-linear-gradient(90deg, var(--color-line) 0 1px, transparent 1px 32px);
  background-size: 32px var(--space-1);
  background-repeat: repeat-x;
  background-position: 0 0;
}

.page-features .feat-group__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1) var(--space-2);
}

.page-features .feat-group__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-ink-muted);
}

.page-features .feat-group__title {
  flex: 1 1 auto;
  min-width: 0;
  margin: 0;
  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-features .feat-group__intro {
  margin: var(--space-2) 0 0;
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-features .feat-group__intro a {
  color: var(--color-accent);
  text-underline-offset: 0.2em;
}

.page-features .feat-group__note {
  margin: var(--space-3) 0 0;
  padding-top: var(--space-2);
  border-top: 1px dashed var(--color-line);
  max-width: var(--measure);
  font-size: var(--text-xs);
  line-height: var(--leading-body);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

/* ---------- 指标行 ---------- */

.page-features .feat-metrics {
  margin: var(--space-3) 0 0;
  padding: 0;
  list-style: none;
  counter-reset: feat-metric;
}

.page-features .feat-metric {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2);
  padding: var(--space-3) 0;
  border-top: 1px dashed var(--color-line);
}

.page-features .feat-metric:first-child {
  border-top: 1px solid var(--color-line);
}

.page-features .feat-metric__id {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: var(--space-2);
  align-items: baseline;
  min-width: 0;
}

.page-features .feat-metric__idx {
  grid-column: 1;
  grid-row: 1;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
}

.page-features .feat-metric__name {
  grid-column: 2;
  grid-row: 1;
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  color: var(--color-ink);
}

.page-features .feat-metric__value {
  grid-column: 1 / -1;
  grid-row: 2;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-1);
  margin: var(--space-1) 0 0;
  font-family: var(--font-mono);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: -0.01em;
  color: var(--color-ink);
}

.page-features .feat-metric__unit {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: var(--weight-body);
  letter-spacing: 0.05em;
  color: var(--color-ink-soft);
}

.page-features .feat-metric--accent .feat-metric__value {
  color: var(--color-accent);
}

.page-features .feat-metric__side {
  min-width: 0;
}

.page-features .feat-metric__def {
  margin: 0;
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* ---------- 口径展开 ---------- */

.page-features .feat-metric__detail {
  margin-top: var(--space-2);
}

.page-features .feat-metric__detail > summary {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 var(--space-2);
  border-radius: var(--radius-sm);
  background: var(--color-primary-soft);
  color: var(--color-ink);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  cursor: pointer;
  list-style: none;
  box-shadow: var(--shadow-1);
  transition: background-color 150ms ease;
}

.page-features .feat-metric__detail > summary::-webkit-details-marker {
  display: none;
}

.page-features .feat-metric__detail > summary::before {
  content: "＋";
  margin-right: var(--space-1);
  font-family: var(--font-mono);
  color: var(--color-accent);
}

.page-features .feat-metric__detail[open] > summary::before {
  content: "－";
}

.page-features .feat-metric__detail > summary:hover {
  background: var(--color-highlight);
}

.page-features .feat-metric__detail > summary:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 2px;
}

.page-features .feat-metric__detail > p {
  margin: var(--space-2) 0 0;
  padding-left: var(--space-2);
  border-left: 1px dashed var(--color-line);
  max-width: var(--measure);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* ---------- 配图 ---------- */

.page-features .feat-figure {
  margin: var(--space-4) 0 0;
}

.page-features .feat-figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius-sm);
  background: var(--color-surface-deep);
}

.page-features .feat-figure figcaption {
  margin-top: var(--space-1);
  max-width: var(--measure);
  font-size: var(--text-xs);
  line-height: var(--leading-body);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

/* ---------- 口径说明区块 ---------- */

.page-features .feat-scope {
  padding: var(--space-4) 0 var(--space-8);
}

.page-features .feat-scope__panel {
  padding: var(--space-4) var(--space-3);
  border-radius: var(--radius-sm);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  box-shadow: var(--shadow-2);
}

.page-features .feat-scope__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-3xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}

.page-features .feat-scope__lead {
  margin: var(--space-2) 0 var(--space-3);
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-contrast-ink);
  opacity: 0.8;
}

.page-features .feat-scope__list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-3);
  margin: var(--space-3) 0 0;
}

.page-features .feat-scope__item {
  min-width: 0;
  padding-top: var(--space-2);
  border-top: 1px dashed var(--color-contrast-line);
}

.page-features .feat-scope__item dt {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-contrast-accent);
}

.page-features .feat-scope__item dd {
  margin: var(--space-1) 0 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-contrast-ink);
  opacity: 0.86;
}

.page-features .feat-scope__help {
  margin: var(--space-4) 0 0;
  padding-top: var(--space-3);
  border-top: 1px dashed var(--color-contrast-line);
  max-width: var(--measure);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-contrast-ink);
}

.page-features .feat-scope__help a {
  color: var(--color-contrast-accent);
  text-underline-offset: 0.2em;
}

/* ---------- 平板起 ---------- */

@media (min-width: 760px) {
  .page-features .feat-hero {
    padding-top: var(--space-4);
    padding-bottom: var(--space-6);
  }

  .page-features .feat-hero__inner {
    padding: var(--space-6) var(--space-6) var(--space-4);
  }

  .page-features .feat-wall {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-features .feat-index {
    padding-bottom: var(--space-4);
  }

  .page-features .feat-group {
    padding: var(--space-6) 0 var(--space-6);
  }

  .page-features .feat-metric {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: var(--space-3) var(--space-4);
    align-items: start;
  }

  .page-features .feat-metric__value {
    grid-row: 2;
    margin-top: var(--space-2);
  }

  .page-features .feat-figure--right {
    max-width: 62%;
    margin-left: auto;
  }

  .page-features .feat-scope__panel {
    padding: var(--space-6);
  }

  .page-features .feat-scope__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-3) var(--space-4);
  }
}

@media (min-width: 1024px) {
  .page-features .feat-group__head {
    align-items: flex-end;
  }

  .page-features .feat-hero h1 {
    max-width: 14ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-features .feat-index__link,
  .page-features .feat-metric__detail > summary {
    transition: none;
  }

  .page-features .feat-index__link:hover {
    transform: none;
  }
}
<<<END>>>