/* ===== 能力清单页 · 页面专属样式 ===== */

.page-features {
  display: block;
  padding-bottom: var(--section-y);
}

/* --- 面包屑条 --- */
.page-features .feat-crumb-bar {
  padding-block: var(--space-3) var(--space-2);
}

/* --- 首屏 --- */
.page-features .feat-hero {
  position: relative;
  padding-block: var(--space-6) var(--section-y);
  isolation: isolate;
}

.page-features .feat-hero::before {
  content: "";
  position: absolute;
  top: -12%;
  right: -8%;
  width: min(560px, 82vw);
  aspect-ratio: 1 / 1;
  background: radial-gradient(circle at 50% 50%,
      color-mix(in srgb, var(--color-primary) 34%, transparent) 0%,
      transparent 68%);
  pointer-events: none;
  z-index: -1;
}

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

.page-features .feat-hero__kicker {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  margin: 0 0 var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  color: var(--color-ink-soft);
  text-transform: uppercase;
}

.page-features .feat-hero__title {
  margin: 0 0 var(--space-4);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-display);
  line-height: 1.04;
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
  overflow-wrap: anywhere;
}

.page-features .feat-hero__lede {
  max-width: var(--measure);
  margin: 0;
  color: var(--color-ink-soft);
}

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

.page-features .feat-stat {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  padding: var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-surface-alt);
}

.page-features .feat-stat:nth-child(odd) {
  box-shadow: var(--shadow-1);
}

.page-features .feat-stat__num {
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  line-height: 1;
  font-weight: var(--weight-heading);
  color: var(--color-accent);
  overflow-wrap: anywhere;
}

.page-features .feat-stat--minor .feat-stat__num {
  color: var(--color-primary);
  font-size: var(--text-3xl);
}

.page-features .feat-stat__label {
  margin: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink);
}

.page-features .feat-stat__note {
  margin: 0;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

/* --- 主体骨架 --- */
.page-features .feat-body {
  display: grid;
  gap: var(--space-6);
}

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

.page-features .feat-toc {
  border-block: var(--border-thin) solid var(--color-line);
  padding-block: var(--space-2);
}

.page-features .feat-toc__caption {
  margin: 0 0 var(--space-2);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
  text-transform: uppercase;
}

.page-features .feat-toc__list {
  display: flex;
  gap: var(--space-1);
  margin: 0;
  padding: 0 0 var(--space-1);
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-features .feat-toc__link {
  display: block;
  white-space: nowrap;
  padding: var(--space-1) var(--space-2);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-soft);
  text-decoration: none;
  transition: color 160ms ease, border-color 160ms ease, background-color 160ms ease;
}

.page-features .feat-toc__link:hover,
.page-features .feat-toc__link:focus-visible {
  color: var(--color-ink);
  border-color: var(--color-primary);
  background: var(--color-surface-alt);
  outline: none;
}

.page-features .feat-toc__link.is-active {
  color: var(--color-accent);
  border-color: var(--color-accent);
  box-shadow: var(--shadow-1);
}

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

/* --- 分组通用 --- */
.page-features [data-section] {
  scroll-margin-top: var(--space-8);
}

.page-features .feat-group {
  padding-block: var(--space-8);
  border-top: var(--border-thin) solid var(--color-line);
}

.page-features .feat-group:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-features .feat-group__head {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.page-features .feat-group__num {
  flex: 0 0 auto;
  font-size: var(--text-2xl);
  line-height: 1;
  font-weight: var(--weight-heading);
  color: var(--color-primary);
}

.page-features .feat-group__title {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-2xl);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

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

.page-features .feat-group__lede {
  max-width: var(--measure);
  margin: 0 0 var(--space-6);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-features .feat-split__text .feat-group__lede {
  margin-bottom: var(--space-4);
}

/* --- 分栏（图 + 文）--- */
.page-features .feat-split {
  display: grid;
  gap: var(--space-6);
}

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

/* --- 图片容器 --- */
.page-features .feat-media {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin: 0;
}

.page-features .feat-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-surface-alt);
}

.page-features .feat-media--band img {
  border-radius: var(--radius-lg);
  aspect-ratio: 16 / 6;
}

.page-features .feat-media--square img {
  aspect-ratio: 1 / 1;
}

.page-features .feat-media--flat img {
  aspect-ratio: 3 / 1;
}

.page-features .feat-media__cap {
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.page-features .feat-media--band {
  margin-bottom: var(--space-6);
}

/* --- 折叠条目 --- */
.page-features .feat-fold {
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-features .feat-fold > summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  gap: var(--space-2);
  align-items: baseline;
  padding-block: var(--space-3);
  cursor: pointer;
  list-style: none;
}

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

.page-features .feat-fold > summary:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.page-features .feat-fold__id {
  font-size: var(--text-xs);
  color: var(--color-primary);
  border: var(--border-thin) solid var(--color-primary);
  border-radius: var(--radius-sm);
  padding: 2px var(--space-1);
  white-space: nowrap;
}

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

.page-features .feat-fold__mark {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  line-height: 1;
  color: var(--color-accent);
}

.page-features .feat-fold__mark::before {
  content: "+";
}

.page-features .feat-fold[open] .feat-fold__mark::before {
  content: "−";
}

.page-features .feat-fold .pg-fold__body {
  padding-bottom: var(--space-3);
  padding-left: 0;
}

.page-features .feat-fold .pg-fold__body p {
  margin: 0 0 var(--space-2);
  color: var(--color-ink-soft);
  line-height: var(--leading-body);
}

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

.page-features .feat-bullets li {
  position: relative;
  padding-left: var(--space-3);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-features .feat-bullets li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
}

/* --- 账目式清单（02 组）--- */
.page-features .feat-ledger {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-features .feat-ledger__row {
  display: grid;
  gap: var(--space-1);
  padding-block: var(--space-3);
  border-top: var(--border-thin) solid var(--color-line);
}

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

.page-features .feat-ledger__id {
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

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

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

.page-features .feat-ledger__meta {
  margin: 0;
  font-size: var(--text-xs);
  font-family: var(--font-mono);
  color: var(--color-ink-muted);
}

/* --- 记录族条目 --- */
.page-features .feat-entry {
  padding-block: var(--space-3);
  border-top: var(--border-thin) solid var(--color-line);
}

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

.page-features .feat-entry__id {
  margin: 0 0 var(--space-1);
  font-size: var(--text-xs);
  color: var(--color-primary);
}

.page-features .feat-entry__title {
  margin: 0 0 var(--space-1);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: var(--leading-heading);
  color: var(--color-ink);
}

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

.page-features .feat-entry a,
.page-features .feat-cross a {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.page-features .feat-entry a:hover,
.page-features .feat-cross a:hover {
  color: var(--color-accent);
}

.page-features .feat-entry a:focus-visible,
.page-features .feat-cross a:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* --- 三列面板（04 组）--- */
.page-features .feat-triad {
  display: grid;
  gap: var(--space-2);
}

.page-features .feat-entry--panel {
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface-alt);
  padding: var(--space-3);
}

.page-features .feat-entry--panel:last-child {
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-features .feat-entry--wide {
  border-color: var(--color-primary);
  background: var(--color-primary-soft);
}

/* --- 术语索引列表（05 组）--- */
.page-features .feat-index-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: var(--space-2);
}

.page-features .feat-index-list__item {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  border-left: var(--border-thick) solid var(--color-primary);
  border-radius: var(--radius-sm);
  background: var(--color-surface-alt);
}

.page-features .feat-index-list__id {
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.page-features .feat-index-list__name {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
  color: var(--color-ink);
}

.page-features .feat-index-list__note {
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* --- 字段与状态（反相区）--- */
.page-features .feat-fields {
  padding-block: var(--section-y);
  margin-top: var(--section-y);
}

.page-features .feat-fields__head {
  margin-bottom: var(--space-4);
}

.page-features .feat-fields__kicker {
  margin: 0 0 var(--space-2);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-contrast-accent);
}

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

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

.page-features .feat-fields .feat-media {
  margin-bottom: var(--space-6);
}

.page-features .feat-fields .feat-media img {
  border-color: var(--color-contrast-line);
  background: var(--color-contrast-surface);
}

.page-features .feat-fields .feat-media__cap {
  color: var(--color-contrast-accent);
}

.page-features .feat-table-scroll {
  overflow-x: auto;
  margin-bottom: var(--space-6);
}

.page-features .feat-table-scroll:last-child {
  margin-bottom: 0;
}

.page-features .feat-table {
  width: 100%;
  min-width: 600px;
  border-collapse: collapse;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
}

.page-features .feat-table__caption {
  text-align: left;
  padding-bottom: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-contrast-accent);
}

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

.page-features .feat-table thead th {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  color: var(--color-contrast-accent);
}

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

.page-features .feat-table tbody tr {
  transition: background-color 160ms ease;
}

.page-features .feat-table tbody tr:hover {
  background: color-mix(in srgb, var(--color-contrast-accent) 10%, transparent);
}

.page-features .feat-table tbody td:nth-child(3) {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-contrast-accent);
}

/* --- 交叉检索 --- */
.page-features .feat-cross {
  padding-block: var(--section-y);
}

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

.page-features .feat-cross__title {
  margin: 0 0 var(--space-3);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-2xl);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

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

.page-features .feat-cross__side {
  padding: var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-surface-alt);
  align-self: start;
}

.page-features .feat-cross__side-title {
  margin: 0 0 var(--space-2);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-accent);
}

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

.page-features .feat-cross__facts li {
  display: flex;
  justify-content: space-between;
  gap: var(--space-2);
  padding-block: var(--space-1);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-features .feat-cross__facts li:last-child {
  border-bottom: 0;
}

.page-features .feat-cross__key {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}

.page-features .feat-cross__val {
  font-size: var(--text-sm);
  color: var(--color-ink);
  text-align: right;
}

.page-features .feat-cross__foot {
  margin: var(--space-3) 0 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* --- 页末提示 --- */
.page-features .feat-tail {
  padding-bottom: var(--space-4);
}

/* ===== 响应式 ===== */
@media (min-width: 640px) {
  .page-features .feat-hero__figures {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-features .feat-stat--minor .feat-stat__num {
    font-size: var(--text-figure);
  }

  .page-features .feat-index-list__item {
    grid-template-columns: 12ch minmax(0, 1fr);
    align-items: baseline;
  }

  .page-features .feat-index-list__note {
    grid-column: 2 / -1;
  }
}

@media (min-width: 880px) {
  .page-features .feat-hero__inner {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    align-items: end;
    gap: var(--space-8);
  }

  .page-features .feat-hero__figures {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-features .feat-split {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: start;
    gap: var(--space-6);
  }

  .page-features .feat-split--reverse {
    grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.22fr);
  }

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

  .page-features .feat-entry--wide {
    grid-column: 1 / -1;
  }

  .page-features .feat-cross__grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    gap: var(--space-8);
    align-items: start;
  }
}

@media (min-width: 1000px) {
  .page-features .feat-body {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: var(--space-8);
    align-items: start;
  }

  .page-features .feat-toc-wrap {
    position: sticky;
    top: var(--space-4);
    align-self: start;
  }

  .page-features .feat-toc {
    padding-block: 0;
    border-block: 0;
    border-left: var(--border-thin) solid var(--color-line);
    padding-left: var(--space-3);
  }

  .page-features .feat-toc__list {
    flex-direction: column;
    overflow-x: visible;
    padding-bottom: 0;
  }

  .page-features .feat-toc__link {
    border-radius: var(--radius-sm);
    white-space: normal;
    border-color: transparent;
  }

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

  .page-features .feat-group:first-child {
    padding-top: 0;
  }
}

@media (min-width: 1180px) {
  .page-features .feat-ledger__row {
    grid-template-columns: 14ch minmax(0, 1fr);
    column-gap: var(--space-4);
    align-items: baseline;
  }

  .page-features .feat-ledger__id {
    grid-row: 1 / 3;
    padding-top: 0.45em;
  }

  .page-features .feat-ledger__title,
  .page-features .feat-ledger__desc,
  .page-features .feat-ledger__meta {
    grid-column: 2;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-features .feat-toc__link,
  .page-features .feat-table tbody tr {
    transition: none;
  }
}