/* ===== 关于我们 / page-about ===== */

.page-about .about-crumb {
  padding-top: var(--space-6);
}

.page-about .about-lead {
  padding-top: var(--space-4);
}

.page-about .about-title {
  margin: var(--space-3) 0 var(--space-4);
  max-width: 20ch;
  font-family: var(--font-heading);
  font-size: var(--text-4xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-about .about-lead__grid {
  display: grid;
  gap: var(--space-6);
}

.page-about .about-lead__text {
  display: grid;
  gap: var(--space-4);
}

.page-about .about-lede {
  margin: 0;
  max-width: var(--measure);
  font-size: var(--text-lg);
  line-height: var(--leading-body);
  color: var(--color-ink);
}

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

.page-about .about-lead__media,
.page-about .about-timeline__media,
.page-about .about-compliance__media {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface-deep);
}

.page-about .about-lead__media img,
.page-about .about-timeline__media img,
.page-about .about-compliance__media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-lead__media::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  border-top: var(--border-thin) solid color-mix(in srgb, var(--color-primary-ink) 55%, transparent);
  pointer-events: none;
}

/* 关键数字带 */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-6) var(--space-3);
  margin: var(--space-8) 0 0;
  padding: var(--space-4) 0 0;
  list-style: none;
  border-top: 1px dotted var(--color-line);
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  font-variant-numeric: tabular-nums;
  line-height: 1;
  color: var(--color-primary);
}

.page-about .about-stat__unit {
  margin-left: 0.15em;
  font-size: var(--text-lg);
  color: var(--color-primary);
}

.page-about .about-stat__label {
  display: block;
  margin-top: var(--space-2);
  max-width: 30ch;
  font-size: var(--text-sm);
  line-height: 1.6;
  color: var(--color-ink-soft);
}

/* 段落索引条 */
.page-about .about-index {
  background: var(--color-contrast-surface);
  border-block: var(--border-thin) solid var(--color-contrast-line);
}

.page-about .about-index__inner {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding-block: var(--space-2);
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .about-index__inner::-webkit-scrollbar {
  display: none;
}

.page-about .about-index__label {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  color: var(--color-contrast-accent);
}

.page-about .about-index__list {
  display: flex;
  gap: var(--space-2);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-index__link {
  display: inline-flex;
  align-items: center;
  padding: 5px var(--space-3);
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  white-space: nowrap;
  text-decoration: none;
  color: var(--color-contrast-ink);
  transition: background-color 160ms ease, border-color 160ms ease, color 160ms ease;
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}

/* 章节头 */
.page-about .about-head {
  margin-bottom: var(--space-6);
}

.page-about .about-head__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-primary);
}

.page-about .about-head__num--contrast {
  color: var(--color-contrast-accent);
}

.page-about .about-head__title {
  margin: var(--space-2) 0 0;
  max-width: 24ch;
  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-about .about-head__intro {
  margin: var(--space-4) 0 0;
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-about .about-head__intro a {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-color: var(--color-primary-soft);
  text-underline-offset: 3px;
}

/* 叙事引导竖线 */
.page-about .about-narrative {
  position: relative;
  padding-left: var(--space-4);
}

.page-about .about-narrative::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.4em;
  bottom: 0.4em;
  width: var(--border-thin);
  background: linear-gradient(180deg, var(--color-primary) 0%, var(--color-line) 65%, transparent 100%);
}

/* 运营原则折叠面板 */
.page-about .principles {
  display: grid;
  gap: var(--space-3);
}

.page-about .principle {
  overflow: hidden;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  transition: border-color 180ms ease, box-shadow 180ms ease;
}

.page-about .principle:hover,
.page-about .principle:focus-within {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-2);
}

.page-about .principle__summary {
  display: flex;
  align-items: baseline;
  gap: var(--space-3);
  padding: var(--space-4);
  cursor: pointer;
  list-style: none;
  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-about .principle__summary::-webkit-details-marker {
  display: none;
}

.page-about .principle__summary::after {
  content: "＋";
  margin-left: auto;
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: var(--text-base);
  color: var(--color-primary);
}

.page-about .principle[open] .principle__summary::after {
  content: "－";
  color: var(--color-accent);
}

.page-about .principle__num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-variant-numeric: tabular-nums;
  color: var(--color-accent);
}

.page-about .principle__body {
  padding: var(--space-3) var(--space-4) var(--space-4);
  border-top: 1px dotted var(--color-line);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-about .principle__body > p {
  margin: 0;
  max-width: var(--measure);
}

.page-about .principle__points {
  display: grid;
  gap: var(--space-2);
  margin: var(--space-3) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .principle__points li {
  position: relative;
  padding-left: var(--space-4);
  max-width: var(--measure);
}

.page-about .principle__points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.85em;
  width: 11px;
  height: var(--border-thin);
  background: var(--color-primary);
}

.page-about .principle__tail {
  margin-top: var(--space-3);
}

.page-about .principle__body a {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-color: var(--color-primary-soft);
  text-underline-offset: 3px;
}

/* 迭代历程横向带 */
.page-about .about-timeline {
  padding-bottom: var(--space-8);
}

.page-about .timeline-band {
  overflow-x: auto;
  padding-bottom: var(--space-3);
  scrollbar-width: thin;
  scrollbar-color: var(--color-primary) transparent;
}

.page-about .timeline-band__track {
  position: relative;
  display: flex;
  gap: var(--space-4);
  min-width: max-content;
  padding-top: var(--space-6);
}

.page-about .timeline-band__track::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 7px;
  height: var(--border-thin);
  background-image: linear-gradient(90deg, var(--color-line) 50%, transparent 0);
  background-size: 12px var(--border-thin);
}

.page-about .phase {
  position: relative;
  flex: 0 0 244px;
  padding-top: var(--space-4);
  border-top: var(--border-thin) solid transparent;
}

.page-about .phase__dot {
  position: absolute;
  top: -1px;
  left: 0;
  width: 15px;
  height: 15px;
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  border: var(--border-thin) solid var(--color-primary);
  transition: background-color 180ms ease, box-shadow 180ms ease;
}

.page-about .phase:hover .phase__dot,
.page-about .phase:focus-visible .phase__dot {
  background: var(--color-accent);
  border-color: var(--color-accent);
  box-shadow: var(--shadow-2);
}

.page-about .phase:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 6px;
  border-radius: var(--radius-sm);
}

.page-about .phase__range {
  display: inline-block;
  padding: 3px var(--space-2);
  border-radius: var(--radius-pill);
  background: var(--color-primary-soft);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-variant-numeric: tabular-nums;
  color: var(--color-primary);
}

.page-about .phase__theme {
  margin: var(--space-3) 0 var(--space-2);
  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-about .phase__desc {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.7;
  color: var(--color-ink-soft);
  opacity: 0.8;
  transition: opacity 180ms ease;
}

.page-about .phase:hover .phase__desc,
.page-about .phase:focus-within .phase__desc {
  opacity: 1;
}

.page-about .about-timeline__media {
  margin-top: var(--space-8);
}

/* 索引维护卡片 */
.page-about .maintain-list {
  display: grid;
  gap: var(--space-4);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .maintain-item {
  padding: var(--space-4);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
}

.page-about .maintain-item__tag {
  display: inline-block;
  margin-bottom: var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
}

.page-about .maintain-item__title {
  margin: 0 0 var(--space-2);
  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-about .maintain-item__text {
  margin: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-about .maintain-item__text a {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-color: var(--color-primary-soft);
  text-underline-offset: 3px;
}

/* 合规与备案深底区块 */
.page-about .about-compliance {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.page-about .about-compliance__grid {
  display: grid;
  gap: var(--space-6);
}

.page-about .about-compliance__title {
  margin: var(--space-2) 0 var(--space-4);
  max-width: 22ch;
  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-about .about-compliance__body {
  margin: 0;
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: color-mix(in srgb, var(--color-contrast-ink) 80%, transparent);
}

.page-about .about-compliance__body .mono {
  color: var(--color-contrast-accent);
  font-variant-numeric: tabular-nums;
}

.page-about .channel-list {
  display: grid;
  gap: var(--space-2);
  margin: var(--space-6) 0 0;
  padding: var(--space-4) 0 0;
  list-style: none;
  border-top: 1px dotted var(--color-contrast-line);
}

.page-about .channel-item {
  display: grid;
  gap: 2px;
}

.page-about .channel-item__key {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-contrast-accent);
}

.page-about .channel-item__val {
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-contrast-ink);
  word-break: break-word;
}

.page-about .about-compliance__note {
  margin: var(--space-6) 0 0;
  max-width: var(--measure);
  font-size: var(--text-sm);
  line-height: 1.7;
  color: color-mix(in srgb, var(--color-contrast-ink) 68%, transparent);
}

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

.page-about .about-compliance__media {
  border-color: var(--color-contrast-line);
  background: color-mix(in srgb, var(--color-contrast-ink) 8%, transparent);
}

/* 能力边界 */
.page-about .boundary-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px dotted var(--color-line);
}

.page-about .boundary-list li {
  display: grid;
  gap: var(--space-2);
  padding: var(--space-4) 0;
  border-bottom: 1px dotted var(--color-line);
}

.page-about .boundary-list__label {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-variant-numeric: tabular-nums;
  color: var(--color-accent);
}

.page-about .boundary-list__text {
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
  max-width: var(--measure);
}

/* 平板与桌面 */
@media (min-width: 760px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .maintain-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .boundary-list li {
    grid-template-columns: 5rem minmax(0, 1fr);
    align-items: baseline;
    gap: var(--space-4);
  }

  .page-about .channel-item {
    grid-template-columns: 7rem minmax(0, 1fr);
    align-items: baseline;
    gap: var(--space-2);
  }

  .page-about .phase {
    flex: 0 0 268px;
  }
}

@media (min-width: 900px) {
  .page-about .about-lead__grid {
    grid-template-columns: 7fr 5fr;
    align-items: start;
    gap: var(--space-8);
  }

  .page-about .about-compliance__grid {
    grid-template-columns: 7fr 5fr;
    align-items: start;
    gap: var(--space-8);
  }

  .page-about .about-compliance__media {
    margin-top: var(--space-6);
  }

  .page-about .about-index__inner {
    overflow-x: visible;
  }
}
</final>