.page-features {
  --feat-pad: var(--space-3);
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  overflow-x: hidden;
}

.page-features .shell {
  min-width: 0;
}

/* ---------- 首屏 ---------- */

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

.page-features .feat-hero__title {
  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-ink);
  margin: var(--space-3) 0 0;
}

.page-features .feat-hero__grid {
  display: grid;
  gap: var(--space-4);
  margin-top: var(--space-6);
}

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

.page-features .feat-fig {
  display: grid;
  gap: 2px;
  padding-left: var(--space-2);
  border-left: var(--border-thick) solid var(--color-primary);
  transition: border-color 200ms ease, background-color 200ms ease;
}

.page-features .feat-fig:hover {
  border-left-color: var(--color-accent);
  background: var(--color-surface-alt);
}

.page-features .feat-fig__n {
  font-family: var(--font-mono);
  font-size: var(--text-2xl);
  font-weight: 700;
  line-height: 1;
  color: var(--color-accent);
}

.page-features .feat-fig__u {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  color: var(--color-ink);
}

.page-features .feat-fig__note {
  font-size: var(--text-xs);
  line-height: 1.6;
  color: var(--color-ink-muted);
  opacity: 0.78;
  transition: opacity 200ms ease, color 200ms ease;
}

.page-features .feat-fig:hover .feat-fig__note {
  opacity: 1;
  color: var(--color-ink-soft);
}

.page-features .feat-demo {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top: 3px solid var(--color-primary);
  border-radius: var(--radius-md);
  padding: var(--space-3);
  display: grid;
  gap: var(--space-2);
}

.page-features .feat-demo__label {
  margin: 0;
  font-size: var(--text-xs);
  letter-spacing: 0.18em;
  color: var(--color-contrast-ink);
  opacity: 0.7;
}

.page-features .feat-demo__score {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-2);
  padding-bottom: var(--space-2);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}

.page-features .feat-demo__side {
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  opacity: 0.75;
}

.page-features .feat-demo__n {
  font-family: var(--font-mono);
  font-size: var(--text-3xl);
  font-weight: 700;
  line-height: 1;
  color: var(--color-contrast-accent);
}

.page-features .feat-demo__sep {
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  color: var(--color-contrast-line);
}

.page-features .feat-demo__round {
  margin: 0;
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-contrast-ink);
  opacity: 0.78;
}

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

.page-features .feat-demo__stats div {
  display: grid;
  gap: 2px;
}

.page-features .feat-demo__stats dt {
  font-size: var(--text-xs);
  color: var(--color-contrast-ink);
  opacity: 0.6;
}

.page-features .feat-demo__stats dd {
  margin: 0;
  font-size: var(--text-lg);
  color: var(--color-contrast-accent);
}

/* ---------- 区块索引 ---------- */

.page-features .feat-index {
  border-top: var(--border-thin) solid var(--color-line);
  border-bottom: var(--border-thin) solid var(--color-line);
  background: var(--color-surface-alt);
}

.page-features .feat-index__inner {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3) var(--space-4);
  padding-top: var(--space-2);
  padding-bottom: var(--space-2);
}

.page-features .feat-index__item {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: var(--border-thick) solid transparent;
  transition: color 200ms ease, border-color 200ms ease;
}

.page-features .feat-index__item:hover,
.page-features .feat-index__item:focus-visible {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

.page-features .feat-index__item[aria-current="true"] {
  color: var(--color-focus);
  border-bottom-color: var(--color-focus);
}

/* ---------- 分组 ---------- */

.page-features .feat-group {
  position: relative;
  padding: var(--section-y) 0;
}

.page-features .feat-group::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  border-top: var(--border-thin) solid var(--color-line);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-features .feat-group__head {
  display: grid;
  gap: var(--space-3);
  margin-bottom: var(--space-6);
}

.page-features .feat-group__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);
  margin: var(--space-2) 0 0;
  padding-left: var(--space-3);
  border-left: var(--border-thick) solid var(--color-primary);
  transition: border-color 200ms ease;
}

.page-features .feat-group__title:hover,
.page-features .feat-group:focus-within .feat-group__title {
  border-left-color: var(--color-accent);
}

.page-features .feat-group__intro {
  margin: var(--space-2) 0 0;
  font-size: var(--text-lg);
  line-height: 1.6;
  color: var(--color-ink-soft);
  max-width: 46ch;
}

.page-features .feat-group__body {
  display: grid;
  gap: var(--space-6);
}

/* ---------- 条目 ---------- */

.page-features .feat-rows {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--space-4);
  min-width: 0;
}

.page-features .feat-row {
  position: relative;
  padding-left: var(--space-3);
}

.page-features .feat-row::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: var(--border-thick);
  height: 100%;
  background: var(--color-primary);
  transform-origin: top center;
  transition: transform 220ms ease, background-color 220ms ease;
}

.page-features .feat-row:hover::before {
  background: var(--color-accent);
  transform: scaleY(1.04);
}

.page-features .feat-row__title {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  color: var(--color-ink);
  margin: 0;
}

.page-features .feat-row__desc {
  margin: var(--space-1) 0 0;
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
  max-width: 62ch;
}

.page-features .feat-row__meta {
  margin: var(--space-1) 0 0;
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
}

.page-features .feat-row__k {
  display: inline-block;
  margin-right: var(--space-1);
  padding-left: var(--space-1);
  border-left: var(--border-thick) solid var(--color-primary);
  color: var(--color-primary);
  letter-spacing: 0.12em;
}

/* ---------- 视觉 ---------- */

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

.page-features .feat-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-features .feat-media .media-frame__caption {
  font-size: var(--text-sm);
}

/* ---------- 折叠边界说明 ---------- */

.page-features .feat-more {
  margin-top: var(--space-4);
  border-top: var(--border-thin) solid var(--color-line);
  border-bottom: var(--border-thin) solid var(--color-line);
  background: var(--color-surface-deep);
}

.page-features .feat-more__sum {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-ink);
  letter-spacing: 0.06em;
}

.page-features .feat-more__sum::-webkit-details-marker {
  display: none;
}

.page-features .feat-more__sum::before {
  content: "＋";
  color: var(--color-primary);
  font-family: var(--font-mono);
}

.page-features .feat-more[open] .feat-more__sum::before {
  content: "－";
}

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

.page-features .feat-more__body {
  margin: 0;
  padding: 0 var(--space-3) var(--space-3);
  font-size: var(--text-sm);
  line-height: 1.75;
  color: var(--color-ink-soft);
  max-width: 64ch;
}

/* ---------- 更新节奏 ---------- */

.page-features .feat-cadence {
  position: relative;
  padding: var(--section-y) 0;
  background: var(--color-surface-alt);
  border-top: var(--border-thin) solid var(--color-line);
}

.page-features .feat-flow-fig {
  margin: 0 0 var(--space-6);
}

.page-features .feat-flow__scroll {
  overflow-x: auto;
}

.page-features .feat-flow {
  display: block;
  width: 100%;
  min-width: 620px;
  height: auto;
}

.page-features .feat-flow__track {
  stroke: var(--color-line);
  stroke-width: 2;
}

.page-features .feat-flow__node {
  fill: var(--color-accent);
}

.page-features .feat-flow__node-ring {
  fill: none;
  stroke: var(--color-accent);
  stroke-width: 2;
}

.page-features .feat-flow__label {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  fill: var(--color-ink);
}

.page-features .feat-flow__sub {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  fill: var(--color-ink-muted);
}

.page-features .feat-flow-fig__cap {
  margin-top: var(--space-2);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.page-features .feat-table-wrap {
  overflow-x: auto;
}

.page-features .feat-table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
  font-size: var(--text-sm);
}

.page-features .feat-table__cap {
  text-align: left;
  padding-bottom: var(--space-2);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  color: var(--color-ink-muted);
}

.page-features .feat-table th,
.page-features .feat-table td {
  text-align: left;
  padding: var(--space-2) var(--space-3);
  vertical-align: top;
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-features .feat-table thead th {
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  color: var(--color-ink);
  border-bottom: var(--border-thick) solid var(--color-primary);
}

.page-features .feat-table tbody th {
  font-weight: var(--weight-heading);
  color: var(--color-ink);
  white-space: nowrap;
}

.page-features .feat-table tbody td {
  color: var(--color-ink-soft);
}

/* ---------- 出口 ---------- */

.page-features .feat-next {
  padding: var(--section-y) 0 var(--section-y-lg);
}

.page-features .feat-next__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--border-thin) solid var(--color-line);
}

.page-features .feat-next__item {
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-features .feat-next__link {
  display: grid;
  gap: var(--space-1) var(--space-3);
  padding: var(--space-3) var(--space-2);
  text-decoration: none;
  color: inherit;
  transition: background-color 200ms ease, padding-left 200ms ease;
}

.page-features .feat-next__k {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  color: var(--color-ink);
  border-left: var(--border-thick) solid var(--color-primary);
  padding-left: var(--space-2);
  transition: border-color 200ms ease;
}

.page-features .feat-next__d {
  font-size: var(--text-sm);
  line-height: 1.75;
  color: var(--color-ink-soft);
  padding-left: var(--space-2);
}

.page-features .feat-next__arrow {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  color: var(--color-accent);
  padding-left: var(--space-2);
  transition: transform 200ms ease;
}

.page-features .feat-next__link:hover,
.page-features .feat-next__link:focus-visible {
  background: var(--color-surface-alt);
  padding-left: var(--space-3);
}

.page-features .feat-next__link:hover .feat-next__k,
.page-features .feat-next__link:focus-visible .feat-next__k {
  border-left-color: var(--color-accent);
}

.page-features .feat-next__link:hover .feat-next__arrow,
.page-features .feat-next__link:focus-visible .feat-next__arrow {
  transform: translateX(4px);
}

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

/* ---------- 响应式 ---------- */

@media (min-width: 900px) {
  .page-features .feat-hero__grid {
    grid-template-columns: minmax(0, 1.7fr) minmax(0, 1fr);
    gap: var(--space-8);
    align-items: start;
  }

  .page-features .feat-group__head {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    gap: var(--space-8);
    align-items: start;
  }

  .page-features .feat-group__body {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: var(--space-8);
    align-items: start;
  }

  .page-features .feat-group--even .feat-group__body {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }

  .page-features .feat-group--even .feat-media {
    order: -1;
  }

  .page-features .feat-next__link {
    grid-template-columns: minmax(0, 3fr) minmax(0, 8fr) auto;
    align-items: baseline;
  }

  .page-features .feat-next__arrow {
    padding-left: 0;
  }
}

@media (min-width: 1060px) {
  .page-features .feat-group--odd .feat-media {
    margin-left: calc(var(--space-4) * -1);
  }

  .page-features .feat-group--even .feat-media {
    margin-right: calc(var(--space-4) * -1);
  }
}

@media (min-width: 1180px) {
  .page-features .feat-hero__grid {
    gap: var(--space-8);
  }
}

@media (max-width: 480px) {
  .page-features .feat-figs {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-features .feat-demo__stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-features .feat-index__inner {
    gap: var(--space-2) var(--space-3);
  }
}