.page-about {
  --about-rail: 118px;
  --about-shadow: 0 20px 40px -32px rgba(0, 0, 0, .92);
  --about-body-text: rgba(244, 235, 220, .82);
  padding-bottom: clamp(48px, 7vw, 96px);
}

.page-about .breadcrumb {
  padding-top: clamp(14px, 2.4vw, 26px);
}

/* ---------- 档案封面 ---------- */
.page-about .about-masthead {
  position: relative;
  overflow: hidden;
  margin-top: clamp(14px, 2.4vw, 26px);
  border-top: 1px solid var(--line-gold);
  border-bottom: 1px solid var(--line-gold);
  background-color: var(--ink-deep);
  background-image:
    linear-gradient(to right, rgba(154, 113, 48, .18) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(154, 113, 48, .11) 1px, transparent 1px);
  background-size: 88px 88px, 88px 88px;
  padding: clamp(26px, 4.2vw, 50px) 0 clamp(32px, 4.6vw, 60px);
}

.page-about .about-masthead::after {
  content: "";
  position: absolute;
  inset-inline-end: -80px;
  inset-block-start: -140px;
  width: 320px;
  height: 320px;
  background: radial-gradient(circle, rgba(224, 162, 60, .22), rgba(224, 162, 60, 0) 68%);
  pointer-events: none;
}

.page-about .about-masthead__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 3.6vw, 46px);
}

.page-about .about-masthead__lead {
  min-width: 0;
}

.page-about h1 {
  margin: 10px 0 0;
  max-width: 24ch;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.85rem, 4.6vw, 3.4rem);
  line-height: 1.18;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-masthead__intro {
  margin: clamp(14px, 2vw, 20px) 0 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--about-body-text);
}

.page-about .about-masthead__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(18px, 2.6vw, 28px);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin: 0;
  border-top: 1px solid var(--line-gold);
  border-left: 1px solid var(--line-gold);
  align-self: end;
}

.page-about .about-facts__cell {
  padding: 11px 13px 13px;
  border-right: 1px solid var(--line-gold);
  border-bottom: 1px solid var(--line-gold);
  background: rgba(6, 22, 18, .62);
  min-width: 0;
}

.page-about .about-facts dt {
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--sage);
}

.page-about .about-facts dd {
  margin: 5px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(15px, 1.9vw, 19px);
  font-weight: 600;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}

/* ---------- 档案段 ---------- */
.page-about .dossier {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(14px, 2.2vw, 24px);
  padding: clamp(34px, 5vw, 64px) 0;
  border-bottom: 1px solid var(--line-paper);
}

.page-about .dossier__rail {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-left: 16px;
  border-left: 1px solid var(--line-gold);
  min-width: 0;
}

.page-about .dossier__rail::before {
  content: "";
  position: absolute;
  inset-inline-start: -4px;
  inset-block-start: 7px;
  width: 7px;
  height: 7px;
  background: var(--amber);
  border-radius: 50%;
}

.page-about .dossier__num {
  font-size: 13px;
  font-weight: 600;
  color: var(--amber);
  letter-spacing: .1em;
}

.page-about .dossier__name {
  font-size: 12px;
  letter-spacing: .22em;
  color: var(--sage);
}

.page-about .dossier__body {
  display: grid;
  gap: clamp(14px, 1.9vw, 22px);
  min-width: 0;
}

.page-about .dossier__body h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.4rem, 2.9vw, 2.05rem);
  line-height: 1.32;
  letter-spacing: -.005em;
  color: var(--paper);
}

.page-about .dossier__body p {
  margin: 0;
  max-width: 66ch;
  font-size: clamp(15px, 1.5vw, 16.5px);
  line-height: 1.85;
  color: var(--about-body-text);
  overflow-wrap: break-word;
}

.page-about .dossier__body--split {
  align-items: start;
}

.page-about .dossier__text {
  display: grid;
  gap: clamp(12px, 1.6vw, 18px);
  min-width: 0;
}

.page-about .about-figure {
  margin: 0;
  min-width: 0;
}

.page-about .about-inline-link {
  max-width: none;
}

/* ---------- 版本时间轴 ---------- */
.page-about .about-tabs {
  margin-top: 4px;
}

.page-about .tablist {
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

.page-about .version-line {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 24px;
  display: grid;
  gap: 14px;
}

.page-about .version-line::before {
  content: "";
  position: absolute;
  inset-block: 8px;
  inset-inline-start: 5px;
  width: 1px;
  background: linear-gradient(to bottom, var(--goldline), rgba(154, 113, 48, .18));
}

.page-about .version-line__item {
  position: relative;
  min-width: 0;
}

.page-about .version-line__item::before {
  content: "";
  position: absolute;
  inset-inline-start: -23px;
  inset-block-start: 14px;
  width: 9px;
  height: 9px;
  background: var(--ink);
  border: 1px solid var(--amber);
  transform: rotate(45deg);
}

.page-about .version-card {
  padding: 13px clamp(13px, 1.8vw, 20px) 15px;
  border: 1px solid rgba(154, 113, 48, .55);
  background: var(--paper-old);
  color: var(--ink);
  box-shadow: var(--about-shadow);
  overflow-wrap: break-word;
}

.page-about .version-card__head {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .version-card__year {
  font-size: 14px;
  font-weight: 600;
  color: var(--cinnabar);
  letter-spacing: .06em;
  border: 1px solid rgba(184, 69, 50, .5);
  padding: 1px 6px;
}

.page-about .version-card h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.02rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .version-card p {
  margin: 7px 0 0;
  max-width: none;
  font-size: 14.5px;
  line-height: 1.78;
  color: #23332d;
}

/* ---------- 团队档案签 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .team-tag {
  border: 1px solid var(--line-gold);
  background: rgba(6, 22, 18, .55);
  min-width: 0;
}

.page-about .team-tag[open] {
  border-color: var(--amber);
  background: rgba(11, 36, 30, .92);
}

.page-about .team-tag__summary {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 13px 14px;
  list-style: none;
  cursor: pointer;
  color: var(--paper);
  font-weight: 600;
  font-size: 14.5px;
}

.page-about .team-tag__summary::-webkit-details-marker {
  display: none;
}

.page-about .team-tag__summary::after {
  content: "+";
  margin-inline-start: auto;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--amber);
}

.page-about .team-tag[open] .team-tag__summary::after {
  content: "–";
}

.page-about .team-tag__summary:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 2px;
}

.page-about .team-tag__num {
  font-size: 12px;
  color: var(--celadon);
  letter-spacing: .08em;
}

.page-about .team-tag__body {
  padding: 0 14px 15px;
}

.page-about .team-tag__body p {
  margin: 0;
  max-width: none;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--about-body-text);
}

/* ---------- 整理方法 ---------- */
.page-about .method-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .method-card {
  padding: 16px 16px 18px;
  border-top: 2px solid var(--celadon);
  background: rgba(6, 22, 18, .62);
  min-width: 0;
}

.page-about .method-card__num {
  display: block;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--celadon);
}

.page-about .method-card h3 {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: 1.12rem;
  font-weight: 700;
  color: var(--amber);
}

.page-about .method-card p {
  margin: 8px 0 0;
  max-width: none;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-body-text);
}

.page-about .note {
  margin: 0;
  max-width: 66ch;
}

/* ---------- 服务范围 ---------- */
.page-about .scope-stats {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line-gold);
  border: 1px solid var(--line-gold);
}

.page-about .scope-stats__cell {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 14px 16px;
  background: var(--ink-deep);
  min-width: 0;
}

.page-about .scope-stats__num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 600;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
  line-height: 1;
}

.page-about .scope-stats__label {
  font-size: 13px;
  line-height: 1.5;
  color: var(--paper-old);
}

/* ---------- 收束入口 ---------- */
.page-about .about-cta {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(16px, 2.4vw, 26px);
  margin-top: clamp(34px, 5vw, 64px);
  padding: clamp(20px, 3vw, 34px);
  border: 1px solid var(--line-gold);
  background:
    linear-gradient(135deg, rgba(224, 162, 60, .12), rgba(224, 162, 60, 0) 58%),
    var(--ink-deep);
}

.page-about .about-cta__head h2 {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 2.6vw, 1.9rem);
  line-height: 1.32;
  color: var(--paper);
}

.page-about .about-cta__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
}

.page-about .about-cta__link {
  display: grid;
  gap: 5px;
  padding: 13px 15px;
  border: 1px solid var(--line-soft);
  background: rgba(11, 36, 30, .7);
  text-decoration: none;
  transition: border-color 180ms var(--ease), transform 180ms var(--ease);
}

.page-about .about-cta__link:hover,
.page-about .about-cta__link:focus-visible {
  border-color: var(--amber);
  transform: translateY(-2px);
}

.page-about .about-cta__link:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 2px;
}

.page-about .about-cta__link-title {
  font-size: 14.5px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .about-cta__link-desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--sage);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .scope-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .scope-stats__cell {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

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

@media (min-width: 900px) {
  .page-about .about-masthead__inner {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .65fr);
    align-items: end;
  }

  .page-about .dossier {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(24px, 3.4vw, 48px);
  }

  .page-about .dossier__rail {
    position: sticky;
    top: 92px;
    align-self: start;
    flex-direction: column;
    align-items: flex-start;
    gap: 9px;
    border-left: 0;
    border-top: 1px solid var(--line-gold);
    padding-left: 0;
    padding-top: 14px;
  }

  .page-about .dossier__rail::before {
    inset-inline-start: 0;
    inset-block-start: -4px;
  }

  .page-about .dossier__body--split {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
    gap: clamp(22px, 3vw, 40px);
  }

  .page-about .dossier__body--split .dossier__text h2 {
    grid-column: 1;
  }

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

@media (min-width: 1080px) {
  .page-about .version-card {
    margin-inline-start: 12px;
  }

  .page-about .version-line__item:nth-child(even) .version-card {
    margin-inline-start: 0;
    margin-inline-end: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-cta__link {
    transition: none;
  }

  .page-about .about-cta__link:hover,
  .page-about .about-cta__link:focus-visible {
    transform: none;
  }
}