.page-about {
  --about-strip-text: #F7F1E6;
  counter-reset: about-chapter;
  background: var(--paper);
  color: var(--text);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

/* 面包屑 */
.page-about .breadcrumb {
  padding-top: clamp(18px, 4vw, 30px);
}

.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  color: var(--text-muted);
}

.page-about .breadcrumb-item a {
  color: var(--text-muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .breadcrumb-item a:hover,
.page-about .breadcrumb-item a:focus-visible {
  color: var(--gold-deep);
  border-bottom-color: var(--gold);
}

.page-about .breadcrumb-item[aria-current="page"] {
  color: var(--ink);
  font-weight: 500;
}

.page-about .breadcrumb-sep {
  color: var(--line);
}

/* 首屏 */
.page-about .about-hero {
  padding-block: clamp(26px, 5vw, 48px) clamp(38px, 6vw, 76px);
  background: linear-gradient(180deg, rgba(217, 106, 18, 0.07), rgba(247, 241, 230, 0) 64%);
}

.page-about .hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 48px);
}

.page-about .hero-lead .eyebrow {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--gold-deep);
}

.page-about .hero-lead h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(29px, 5.4vw, 56px);
  line-height: 1.18;
  letter-spacing: 0.05em;
  color: var(--ink);
}

.page-about .hero-lead h1::after {
  content: "";
  display: block;
  width: clamp(56px, 12vw, 104px);
  height: 4px;
  margin-top: clamp(16px, 2.4vw, 26px);
  background: linear-gradient(90deg, var(--gold), var(--gold-light));
}

.page-about .hero-lead .lede {
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.15vw, 17px);
  line-height: 1.85;
  color: var(--ink);
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .hero-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(14px, 2vw, 22px);
  padding-top: clamp(16px, 2vw, 22px);
  border-top: 2px solid var(--ink);
}

.page-about .fact {
  display: flex;
  flex-direction: column;
  gap: 5px;
  min-width: 0;
}

.page-about .fact-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--gold-deep);
}

.page-about .fact-label {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--text-muted);
}

/* 横向色带 */
.page-about .about-band {
  background: linear-gradient(90deg, var(--gold), var(--gold-light));
  color: var(--ink-deep);
}

.page-about .about-band-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 18px;
  padding-block: clamp(14px, 2vw, 20px);
}

.page-about .band-tag {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  padding: 4px 10px;
  background: var(--ink-deep);
  color: var(--gold-light);
  white-space: nowrap;
}

.page-about .about-band p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.65;
  font-weight: 500;
}

/* 章节骨架 */
.page-about .chapter {
  padding-block: clamp(44px, 7vw, 86px);
  border-top: 1px solid var(--line);
}

.page-about .chapter--tint {
  background: var(--paper-white);
}

.page-about .chapter-head {
  display: grid;
  gap: 10px;
  max-width: 72ch;
  margin-bottom: clamp(24px, 3.6vw, 42px);
}

.page-about .chapter-index {
  counter-increment: about-chapter;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--gold);
}

.page-about .chapter-index::before {
  content: counter(about-chapter, decimal-leading-zero);
  font-weight: 700;
}

.page-about .chapter-index::after {
  content: "";
  display: block;
  width: clamp(28px, 6vw, 56px);
  height: 1px;
  background: currentColor;
}

.page-about .section-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(22px, 3.4vw, 36px);
  line-height: 1.3;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.page-about .section-note {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-muted);
  max-width: 62ch;
}

.page-about .grid {
  gap: clamp(24px, 3.4vw, 48px);
}

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

.page-about .copy p {
  margin: 0 0 1em;
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.85;
  color: var(--ink);
}

.page-about .copy p:last-child {
  margin-bottom: 0;
}

/* 侧栏 */
.page-about .side-card {
  border: 1px solid var(--line);
  border-left: 3px solid var(--gold);
  background: var(--paper-white);
  padding: clamp(18px, 2.4vw, 26px);
  box-shadow: var(--shadow-soft);
  min-width: 0;
}

.page-about .side-card-kicker {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.06em;
  color: var(--gold-deep);
}

.page-about .side-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 11px;
}

.page-about .side-list li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--ink);
}

.page-about .side-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--teal);
}

/* 图片 */
.page-about .media {
  margin: 0;
  min-width: 0;
}

.page-about .media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--line);
  background: var(--paper-white);
}

.page-about .media-caption {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--text-muted);
}

.page-about .media--phone img {
  max-width: 340px;
  margin-inline: auto;
}

.page-about .media--timeline {
  margin-top: clamp(28px, 4vw, 44px);
}

/* 索引表 */
.page-about .index-table {
  width: 100%;
  margin-top: clamp(30px, 4.4vw, 52px);
  border-collapse: collapse;
  font-size: 14.5px;
}

.page-about .index-table caption {
  text-align: left;
  padding-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--text-muted);
}

.page-about .index-table th,
.page-about .index-table td {
  text-align: left;
  padding: 14px 12px;
  vertical-align: top;
  line-height: 1.7;
}

.page-about .index-table thead th {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  border-bottom: 2px solid var(--ink);
}

.page-about .index-table tbody tr {
  border-bottom: 1px solid var(--line);
  transition: background-color var(--dur) var(--ease);
}

.page-about .index-table tbody tr:hover {
  background: rgba(217, 106, 18, 0.08);
}

.page-about .index-table tbody th {
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
}

.page-about .index-table tbody td {
  color: var(--ink);
}

.page-about .index-table tbody td + td {
  color: var(--text-muted);
}

/* 记录行为清单 */
.page-about .behavior-list {
  list-style: none;
  margin: clamp(24px, 3.4vw, 34px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .behavior-list li {
  display: grid;
  grid-template-columns: 5em minmax(0, 1fr);
  gap: 12px;
  padding: 13px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--text-muted);
}

.page-about .behavior-list strong {
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--ink);
}

/* 规模 */
.page-about .stat-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .stat-grid li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: clamp(16px, 2.2vw, 26px);
  background: var(--paper-white);
  min-width: 0;
}

.page-about .stat-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(21px, 2.8vw, 30px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--ink);
}

.page-about .stat-label {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--text-muted);
}

.page-about .scale-note {
  margin: clamp(20px, 3vw, 30px) 0 0;
  max-width: 68ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-muted);
}

/* 时间轴 */
.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .timeline-item {
  position: relative;
  padding: 0 0 26px 24px;
  border-left: 1px solid var(--line);
}

.page-about .timeline-item:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 6px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--gold);
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .timeline-item:last-child::before {
  background: var(--teal);
  border-color: var(--teal);
}

.page-about .timeline-item:hover::before {
  background: var(--gold);
}

.page-about .timeline-year {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--gold-deep);
  margin-bottom: 6px;
}

.page-about .timeline-title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .timeline-text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-muted);
  max-width: 40ch;
}

/* 合作 */
.page-about .coop-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(18px, 2.6vw, 26px);
}

.page-about .coop-item {
  padding-top: 16px;
  border-top: 2px solid var(--gold);
  min-width: 0;
}

.page-about .coop-item:nth-child(2) {
  border-top-color: var(--teal);
}

.page-about .coop-item:nth-child(3) {
  border-top-color: var(--violet);
}

.page-about .coop-item h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .coop-item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-muted);
}

.page-about .coop-note {
  margin: clamp(20px, 3vw, 30px) 0 0;
  max-width: 66ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink);
}

/* 深色联络区 */
.page-about .contact-strip {
  margin-top: clamp(28px, 4vw, 44px);
  display: grid;
  gap: clamp(18px, 2.6vw, 30px);
  padding: clamp(20px, 3vw, 34px);
  background: var(--ink);
  color: var(--about-strip-text);
}

.page-about .contact-strip h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(18px, 2.1vw, 23px);
  line-height: 1.4;
  color: var(--paper-white);
}

.page-about .contact-strip p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--line);
  max-width: 52ch;
}

.page-about .contact-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
  min-width: 0;
}

.page-about .contact-links a {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--gold-light);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  word-break: break-all;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .contact-links a:hover,
.page-about .contact-links a:focus-visible {
  color: var(--paper-white);
  border-bottom-color: var(--gold-light);
}

.page-about .chapter-tail {
  margin: clamp(22px, 3vw, 30px) 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  font-size: 14px;
}

.page-about .chapter-tail .link-arrow {
  color: var(--gold-deep);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .chapter-tail .link-arrow:hover,
.page-about .chapter-tail .link-arrow:focus-visible {
  color: var(--ink);
  border-bottom-color: var(--gold);
}

/* 响应式 */
@media (min-width: 760px) {
  .page-about .stat-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 860px) {
  .page-about .timeline {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    column-gap: clamp(12px, 1.6vw, 22px);
  }

  .page-about .timeline-item {
    padding: 44px 0 0 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .page-about .timeline-item::before {
    left: 0;
    top: -5px;
  }

  .page-about .timeline-item:last-child {
    border-top-color: transparent;
  }

  .page-about .timeline-text {
    max-width: none;
  }
}

@media (min-width: 940px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
  }

  .page-about .contact-strip {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: center;
  }
}

@media (max-width: 859px) {
  .page-about .grid-7-5,
  .page-about .grid-5-7,
  .page-about .grid-8-4,
  .page-about .grid-4-8 {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .media--wide img,
  .page-about .media--timeline img {
    max-height: 420px;
  }
}

@media (max-width: 719px) {
  .page-about .index-table thead {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
  }

  .page-about .index-table tbody tr {
    display: block;
    padding: 16px 0;
  }

  .page-about .index-table tbody th,
  .page-about .index-table tbody td {
    display: block;
    padding: 0;
    border: 0;
    white-space: normal;
  }

  .page-about .index-table tbody th {
    margin-bottom: 8px;
    font-size: 16px;
  }

  .page-about .index-table tbody td + td {
    margin-top: 6px;
  }

  .page-about .behavior-list li {
    grid-template-columns: 3.6em minmax(0, 1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms;
    animation-duration: 0.01ms;
  }
}