.page-about {
  --about-rail-w: 96px;
  --about-rail-gap: 40px;
  display: block;
}

/* ---------- 面包屑与首屏 ---------- */

.page-about .breadcrumb {
  padding-top: 20px;
}

.page-about .about-intro {
  padding-top: 26px;
  padding-bottom: 40px;
}

.page-about .about-intro h1 {
  font-family: var(--font-head);
  font-weight: 600;
  font-size: clamp(30px, 4.4vw, 56px);
  line-height: 1.08;
  letter-spacing: -0.005em;
  color: var(--paper);
  margin: 12px 0 0;
  max-width: 19ch;
}

.page-about .about-intro__lead {
  margin: 20px 0 0;
  padding-left: 16px;
  border-left: 2px solid var(--green);
  color: var(--text);
  font-size: 17px;
  line-height: 1.75;
  max-width: 60ch;
}

.page-about .about-intro__stats {
  list-style: none;
  margin: 36px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
  background: var(--line);
  border: 2px solid var(--line-strong);
  box-shadow: var(--shadow-hard);
}

.page-about .about-intro__stats li {
  background: var(--ink-1);
  padding: 18px 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .about-stat__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 34px;
  line-height: 1;
  color: var(--green);
  letter-spacing: -0.01em;
}

.page-about .about-stat__plus {
  font-size: 22px;
  color: var(--green-soft);
}

.page-about .about-stat__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 页面骨架：左索引 + 右正文 ---------- */

.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 20px 72px;
}

.page-about .section-rail {
  position: sticky;
  top: var(--header-h);
  z-index: 20;
  margin: 0 -20px 26px;
  padding: 10px 20px;
  background: var(--ink-0);
  border-top: 2px solid var(--line);
  border-bottom: 2px solid var(--line);
  overflow-x: auto;
  overflow-y: hidden;
}

.page-about .rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 20px;
  white-space: nowrap;
}

.page-about .rail-link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 3px 0;
  text-decoration: none;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.4;
  transition: color var(--dur) var(--ease);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--green-soft);
}

.page-about .rail-link:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 2px;
}

.page-about .rail-no {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--green);
}

.page-about .rail-txt {
  white-space: nowrap;
}

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

/* ---------- 章节通用 ---------- */

.page-about .about-section {
  border-top: 2px solid var(--line);
  padding-top: 40px;
  margin-top: 40px;
  scroll-margin-top: calc(var(--header-h) + 86px);
}

.page-about .about-section:first-child {
  border-top: 0;
  padding-top: 0;
  margin-top: 0;
}

.page-about .about-section__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 16px;
}

.page-about .about-section__no {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.08em;
  color: var(--green);
  flex: none;
}

.page-about .about-section h2 {
  font-family: var(--font-head);
  font-weight: 600;
  font-size: clamp(23px, 2.7vw, 32px);
  line-height: 1.2;
  color: var(--paper);
  margin: 0;
}

.page-about .about-section h3 {
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 18px;
  line-height: 1.35;
  color: var(--paper);
  margin: 0;
}

.page-about .about-section p {
  color: var(--text);
  font-size: 16px;
  line-height: 1.75;
  max-width: 40em;
  margin: 0 0 14px;
}

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

.page-about .about-lede {
  font-size: 17px;
  color: var(--text);
  max-width: 46em;
  margin-bottom: 24px;
}

.page-about .about-section a {
  color: var(--green);
  text-decoration: none;
  border-bottom: 1px solid var(--line-strong);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-section a:hover {
  color: var(--green-soft);
  border-color: var(--green);
}

/* ---------- 图片与图注 ---------- */

.page-about .media-frame {
  border: 2px solid var(--line-strong);
  background: var(--ink-2);
  box-shadow: var(--shadow-hard);
  overflow: hidden;
  border-radius: var(--radius);
}

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

.page-about .img-caption {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-figure {
  margin: 30px 0 0;
  max-width: 100%;
}

/* ---------- 01 起步与定位 ---------- */

.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
}

.page-about .about-split__figure {
  margin: 0;
}

/* ---------- 02 覆盖版图 ---------- */

.page-about .coverage__matrix {
  border: 2px solid var(--line-strong);
  background: var(--ink-1);
  box-shadow: var(--shadow-hard);
  border-radius: var(--radius);
  padding: 20px;
  overflow-x: auto;
}

.page-about .about-matrix {
  display: block;
  width: 100%;
  min-width: 520px;
  height: auto;
}

.page-about .mx-box {
  fill: var(--ink-2);
  stroke: var(--line-strong);
  stroke-width: 2;
}

.page-about .mx-box--cup {
  fill: var(--indigo);
  stroke: var(--indigo-soft);
}

.page-about .mx-box--europa {
  fill: var(--wine);
  stroke: var(--wine-soft);
}

.page-about .mx-code {
  font-family: var(--font-mono);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.06em;
  fill: var(--green);
  text-anchor: middle;
}

.page-about .mx-name {
  font-family: var(--font-body);
  font-size: 11px;
  fill: var(--muted);
  text-anchor: middle;
}

.page-about .coverage__stats {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
  background: var(--line);
  border: 2px solid var(--line-strong);
}

.page-about .coverage__stats li {
  background: var(--ink-1);
  padding: 18px 20px;
}

.page-about .coverage__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 30px;
  line-height: 1;
  color: var(--paper);
}

.page-about .coverage__unit {
  display: block;
  margin-top: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--yellow);
}

.page-about .coverage__stats p {
  margin: 12px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
  max-width: 30em;
}

/* ---------- 03 发展历程 ---------- */

.page-about .about-timeline {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--line-strong);
}

.page-about .timeline-item {
  position: relative;
  padding: 0 0 28px 38px;
}

.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 5px;
  width: 16px;
  height: 16px;
  background: var(--ink-0);
  border: 2px solid var(--green);
  border-radius: var(--radius);
  transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .timeline-item:hover::before {
  background: var(--green);
  transform: translateY(-2px);
}

.page-about .timeline-item:last-child {
  padding-bottom: 0;
}

.page-about .tl-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 8px;
}

.page-about .tl-year {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 22px;
  line-height: 1;
  color: var(--green);
  letter-spacing: 0.01em;
  flex: none;
}

.page-about .timeline-item p {
  font-size: 15px;
  max-width: 42em;
}

/* ---------- 04 采编团队 ---------- */

.page-about .crew-grid {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  border-top: 2px solid var(--line-strong);
  border-left: 2px solid var(--line-strong);
}

.page-about .crew-item {
  background: var(--ink-1);
  border-right: 2px solid var(--line-strong);
  border-bottom: 2px solid var(--line-strong);
  padding: 18px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: background var(--dur) var(--ease);
}

.page-about .crew-item:hover {
  background: var(--ink-2);
}

.page-about .crew-no {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--green);
}

.page-about .crew-name {
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 19px;
  line-height: 1.3;
  color: var(--paper);
}

.page-about .crew-scope {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .crew-note {
  margin-top: 22px;
  padding: 18px 20px;
  border-left: 2px solid var(--yellow);
  background: var(--ink-1);
}

.page-about .crew-note p {
  margin: 0;
  font-size: 15px;
  color: var(--text);
}

/* ---------- 05 数据标准 ---------- */

.page-about .std-list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
  background: var(--line);
  border: 2px solid var(--line-strong);
}

.page-about .std-item {
  background: var(--ink-1);
  padding: 20px;
  transition: background var(--dur) var(--ease);
}

.page-about .std-item:hover {
  background: var(--ink-2);
}

.page-about .std-no {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--brick-soft);
  margin-bottom: 8px;
}

.page-about .std-item h3 {
  margin-bottom: 8px;
}

.page-about .std-item p {
  font-size: 14px;
  line-height: 1.72;
  color: var(--muted);
  max-width: 34em;
}

/* ---------- 06 合作生态 ---------- */

.page-about .partner-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: 24px;
}

.page-about .partner-card {
  border: 2px solid var(--line-strong);
  background: var(--ink-1);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hard);
  padding: 22px 20px;
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .partner-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lift);
}

.page-about .partner-card h3 {
  margin-bottom: 10px;
}

.page-about .partner-card p {
  font-size: 14px;
  line-height: 1.72;
  color: var(--muted);
}

.page-about .partner-tail {
  margin-top: 22px;
  font-size: 15px;
  color: var(--text);
}

/* ---------- 07 服务方式 ---------- */

.page-about .svc-list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  border-top: 2px solid var(--line-strong);
}

.page-about .svc-item {
  border-bottom: 2px solid var(--line-strong);
  padding: 22px 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .svc-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .svc-no {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--green);
  flex: none;
}

.page-about .svc-desc {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text);
  max-width: 44em;
}

.page-about .svc-item .btn {
  justify-self: start;
}

/* ---------- 联系区块 ---------- */

.page-about .about-contact {
  margin-top: 56px;
  padding: 40px 0 48px;
  background: var(--paper);
  border-top: 2px solid var(--line-strong);
}

.page-about .about-contact__inner {
  display: grid;
  gap: 16px;
}

.page-about .about-contact h2 {
  font-family: var(--font-head);
  font-weight: 600;
  font-size: clamp(22px, 2.8vw, 32px);
  line-height: 1.2;
  color: var(--ink-0);
  margin: 0;
}

.page-about .about-contact p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-1);
  max-width: 64ch;
}

.page-about .about-contact__link {
  justify-self: start;
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--ink-0);
  text-decoration: none;
  border-bottom: 2px solid var(--green);
  padding-bottom: 3px;
  transition: color var(--dur) var(--ease);
}

.page-about .about-contact__link:hover,
.page-about .about-contact__link:focus-visible {
  color: var(--wine);
}

.page-about .about-contact__link:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 3px;
}

/* ---------- 响应式 ---------- */

@media (min-width: 700px) {
  .page-about .about-intro__stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

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

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

@media (min-width: 900px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: 40px;
    align-items: start;
  }

  .page-about .svc-item {
    grid-template-columns: 300px minmax(0, 1fr) auto;
    gap: 26px;
    align-items: start;
  }

  .page-about .svc-item .btn {
    justify-self: end;
  }
}

@media (min-width: 1000px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: var(--about-rail-gap);
    padding: 8px 32px 88px 28px;
  }

  .page-about .section-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    margin: 0;
    padding: 4px 14px 4px 0;
    background: transparent;
    border-top: 0;
    border-bottom: 0;
    border-right: 2px solid var(--line);
    overflow: visible;
  }

  .page-about .rail-list {
    flex-direction: column;
    gap: 16px;
    white-space: normal;
  }

  .page-about .rail-link {
    flex-direction: column;
    align-items: flex-start;
    gap: 3px;
    font-size: 12px;
    line-height: 1.45;
  }

  .page-about .rail-txt {
    white-space: normal;
  }

  .page-about .about-section {
    scroll-margin-top: calc(var(--header-h) + 24px);
  }

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

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

@media (min-width: 1200px) {
  .page-about .about-contact__inner {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr);
    align-items: start;
    column-gap: 48px;
    row-gap: 18px;
  }

  .page-about .about-contact h2 {
    grid-column: 1;
    grid-row: 1;
  }

  .page-about .about-contact p {
    grid-column: 2;
    grid-row: 1 / span 2;
  }

  .page-about .about-contact__link {
    grid-column: 1;
    grid-row: 2;
  }
}