.page-about {
  --about-rail-w: 216px;
  --about-line: rgba(226, 231, 223, 0.10);
  --about-line-strong: rgba(226, 231, 223, 0.18);
  --about-body: #C2CCD7;
  --about-body-dim: #B9C4D0;
  --about-sunken: rgba(10, 22, 38, 0.52);

  position: relative;
  overflow-x: clip;
  padding-top: 96px;
  padding-bottom: 72px;
  background-color: var(--ink-900);
  background-image:
    linear-gradient(rgba(245, 247, 243, 0.028) 1px, transparent 1px),
    linear-gradient(90deg, rgba(245, 247, 243, 0.028) 1px, transparent 1px);
  background-size: 48px 48px, 48px 48px;
  color: var(--chalk);
  font-family: var(--font-body);
}

.page-about .about-shell {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 20px;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: 22px 0 36px;
}

.page-about .about-hero .eyebrow {
  font-family: var(--font-display);
  letter-spacing: 0.12em;
  color: var(--turf-bright);
}

.page-about .about-hero h1 {
  margin: 14px 0 16px;
  max-width: 18em;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(28px, 5.6vw, 46px);
  line-height: 1.24;
  letter-spacing: 0.01em;
  color: var(--chalk);
}

.page-about .about-lede {
  max-width: 60ch;
  margin: 0;
  font-size: 16.5px;
  line-height: 1.82;
  color: var(--about-body);
}

.page-about .hero-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .hero-facts li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px 16px;
  border: 1px solid var(--about-line);
  border-left: 3px solid var(--turf);
  border-radius: var(--radius-lg);
  background: var(--panel);
}

.page-about .hero-facts li:nth-child(2) {
  border-left-color: var(--turf-bright);
}

.page-about .hero-facts li:nth-child(3) {
  border-left-color: var(--turf-bright);
}

.page-about .hero-facts li:nth-child(4) {
  border-left-color: var(--lime);
}

.page-about .num-lg {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 30px;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--chalk);
}

.page-about .fact-label {
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--neutral);
}

/* ---------- 主栅格 ---------- */

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

/* ---------- 左侧赛季刻度栏 ---------- */

.page-about .season-rail {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(148px, 1fr));
  gap: 16px;
  padding: 18px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-lg);
  background: var(--panel);
}

.page-about .rail-title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--neutral);
}

.page-about .rail-list {
  display: grid;
  gap: 4px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .rail-list a {
  display: block;
  padding: 7px 10px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  color: var(--about-body-dim);
  font-size: 13.5px;
  line-height: 1.5;
  text-decoration: none;
  transition: background var(--t-fast) ease, border-color var(--t-fast) ease, color var(--t-fast) ease;
}

.page-about .rail-list a:hover {
  background: rgba(30, 122, 71, 0.24);
  border-color: var(--turf-bright);
  color: var(--chalk);
}

.page-about .rail-list a:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 2px;
  background: rgba(30, 122, 71, 0.24);
  color: var(--chalk);
}

.page-about .rail-list--seasons .mono {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 13.5px;
  color: var(--turf-bright);
  margin-right: 6px;
}

/* ---------- 堆叠面板 ---------- */

.page-about .about-stack {
  display: grid;
  gap: 22px;
  min-width: 0;
}

.page-about .about-panel {
  padding: 22px 18px 24px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-xl);
  background: var(--panel);
  transition: border-color var(--t-fast) ease, background var(--t-fast) ease;
}

.page-about .about-panel:hover {
  border-color: rgba(99, 208, 140, 0.55);
  background: var(--panel-lift);
}

.page-about .panel-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: var(--rule) solid var(--about-line);
}

.page-about .panel-index {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--lime);
}

.page-about .panel-title {
  flex: 1 1 auto;
  min-width: 0;
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(19px, 3.4vw, 26px);
  line-height: 1.36;
  color: var(--chalk);
}

.page-about .panel-status {
  margin-left: auto;
  flex: 0 0 auto;
  font-size: 12px;
}

.page-about .panel-lede {
  max-width: 66ch;
  margin: 0 0 20px;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--about-body);
}

.page-about .about-panel p {
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-body);
}

.page-about .about-panel a {
  color: var(--turf-bright);
}

.page-about .about-panel a:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 2px;
}

/* ---------- 图片容器 ---------- */

.page-about .about-figure,
.page-about .team-figure,
.page-about .codes-figure {
  margin: 0 0 20px;
  border: 1px solid var(--about-line-strong);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--ink-black);
}

.page-about .about-figure {
  aspect-ratio: 21 / 9;
}

.page-about .team-figure {
  aspect-ratio: 3 / 2;
  margin: 22px 0 0;
}

.page-about .codes-figure {
  aspect-ratio: 1 / 1;
  margin: 0;
}

.page-about .about-figure img,
.page-about .team-figure img,
.page-about .codes-figure img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

/* ---------- 时间线 ---------- */

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

.page-about .timeline-node {
  position: relative;
  padding: 16px 16px 16px 18px;
  border: 1px solid var(--about-line);
  border-left: 3px solid var(--turf);
  border-radius: var(--radius-lg);
  background: var(--about-sunken);
  transition: background var(--t-fast) ease, border-color var(--t-fast) ease;
}

.page-about .timeline-node:nth-child(2) {
  border-left-color: var(--turf-bright);
}

.page-about .timeline-node:nth-child(3) {
  border-left-color: var(--lime);
}

.page-about .timeline-node:hover {
  background: rgba(10, 22, 38, 0.86);
  border-top-color: var(--about-line-strong);
  border-right-color: var(--about-line-strong);
  border-bottom-color: var(--about-line-strong);
}

.page-about .timeline-year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--turf-bright);
}

.page-about .timeline-title {
  margin: 6px 0 6px;
  font-family: var(--font-serif);
  font-size: 16.5px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--chalk);
}

.page-about .timeline-node p {
  margin: 0 0 10px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--about-body-dim);
}

.page-about .timeline-stat {
  display: inline-block;
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  background: rgba(99, 208, 140, 0.12);
  color: var(--turf-bright);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.05em;
}

.page-about .note {
  margin: 18px 0 0;
  padding: 10px 0 10px 14px;
  border-left: 4px solid var(--turf-bright);
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--neutral);
}

/* ---------- 分类编号 ---------- */

.page-about .codes-intro {
  display: grid;
  gap: 18px;
  margin-bottom: 24px;
}

.page-about .codes-intro__text p {
  margin: 0 0 12px;
  font-size: 15px;
  line-height: 1.82;
  color: var(--about-body);
}

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

.page-about .code-groups {
  display: grid;
  gap: 22px;
}

.page-about .code-group__title {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  color: var(--neutral);
}

.page-about .code-group__title::before {
  content: "";
  flex: 0 0 auto;
  width: 14px;
  height: 14px;
  border-radius: 4px;
  background: var(--turf);
}

.page-about .code-group__title--g2::before {
  background: var(--turf-bright);
}

.page-about .code-group__title--g3::before {
  background: var(--lime);
}

.page-about .code-group__title--g4::before {
  background: var(--neutral);
}

.page-about .code-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(148px, 1fr));
  gap: 10px;
}

.page-about .code-card {
  border: 1px solid var(--about-line-strong);
  border-radius: var(--radius-md);
  background: var(--about-sunken);
  overflow: hidden;
  transition: border-color var(--t-fast) ease, background var(--t-fast) ease;
}

.page-about .code-card summary {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-height: 74px;
  padding: 12px 13px;
  list-style: none;
  cursor: pointer;
}

.page-about .code-card summary::-webkit-details-marker {
  display: none;
}

.page-about .code-card summary::marker {
  content: "";
}

.page-about .code-card summary:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: -2px;
}

.page-about .code-num {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--turf-bright);
}

.page-about .code-name {
  font-size: 13px;
  line-height: 1.5;
  color: var(--about-body-dim);
}

.page-about .code-desc {
  margin: 0;
  padding: 10px 13px 14px;
  border-top: 1px solid var(--about-line);
  font-size: 12.5px;
  line-height: 1.72;
  color: var(--neutral);
}

.page-about .code-card:hover {
  border-color: var(--turf-bright);
}

.page-about .code-card[open] {
  border-color: var(--turf-bright);
  background: rgba(20, 39, 63, 0.92);
}

/* ---------- 团队 ---------- */

.page-about .team-grid {
  display: grid;
  gap: 12px;
}

.page-about .team-card {
  padding: 18px 16px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-lg);
  background: var(--about-sunken);
  transition: border-color var(--t-fast) ease, transform var(--t-fast) ease;
}

.page-about .team-card:hover {
  border-color: var(--turf-bright);
  transform: translateY(-2px);
}

.page-about .team-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 700;
  line-height: 1;
  color: var(--turf-bright);
}

.page-about .team-card h3 {
  margin: 10px 0 8px;
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 600;
  color: var(--chalk);
}

.page-about .team-card p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--about-body-dim);
}

/* ---------- 流程树 ---------- */

.page-about .flow-tree {
  position: relative;
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 4px 0 4px 26px;
  list-style: none;
}

.page-about .flow-tree::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 14px;
  bottom: 14px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--turf), var(--turf-bright) 55%, var(--lime));
  opacity: 0.8;
}

.page-about .flow-step {
  position: relative;
}

.page-about .flow-step::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 15px;
  width: 12px;
  height: 12px;
  border: 2px solid var(--turf-bright);
  border-radius: 50%;
  background: var(--ink-900);
}

.page-about .flow-step:nth-child(3)::before,
.page-about .flow-step:nth-child(4)::before {
  border-color: var(--lime);
}

.page-about .flow-body {
  padding: 14px 16px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-lg);
  background: var(--about-sunken);
  transition: border-color var(--t-fast) ease;
}

.page-about .flow-body:hover {
  border-color: var(--turf-bright);
}

.page-about .flow-when {
  display: inline-block;
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  background: rgba(201, 242, 77, 0.14);
  color: var(--lime);
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.06em;
}

.page-about .flow-body h3 {
  margin: 8px 0 6px;
  font-family: var(--font-serif);
  font-size: 16px;
  font-weight: 600;
  color: var(--chalk);
}

.page-about .flow-body p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--about-body-dim);
}

/* ---------- 合作与引用 ---------- */

.page-about .coop-grid {
  display: grid;
  gap: 12px;
}

.page-about .coop-card {
  padding: 18px 16px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-lg);
  background: var(--about-sunken);
  transition: border-color var(--t-fast) ease;
}

.page-about .coop-card:hover {
  border-color: var(--turf-bright);
}

.page-about .coop-card h3 {
  margin: 10px 0 8px;
  font-family: var(--font-serif);
  font-size: 16.5px;
  font-weight: 600;
  color: var(--chalk);
}

.page-about .coop-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-body-dim);
}

.page-about .coop-card a {
  color: var(--turf-bright);
  text-underline-offset: 3px;
}

/* ---------- 订阅与联系 ---------- */

.page-about .about-panel--start {
  background: linear-gradient(135deg, rgba(30, 122, 71, 0.34), rgba(20, 39, 63, 0.94) 62%);
  border-color: rgba(99, 208, 140, 0.48);
}

.page-about .about-panel--start:hover {
  border-color: var(--lime);
  background: linear-gradient(135deg, rgba(30, 122, 71, 0.4), rgba(20, 39, 63, 0.96) 62%);
}

.page-about .start-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 4px;
}

.page-about .start-actions .btn:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 3px;
}

/* ---------- 窄屏修正 ---------- */

@media (max-width: 400px) {
  .page-about .hero-facts {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .code-cards {
    grid-template-columns: minmax(0, 1fr);
  }
}

/* ---------- 中等屏 ---------- */

@media (min-width: 640px) {
  .page-about .about-shell {
    padding: 0 28px;
  }

  .page-about .about-panel {
    padding: 28px 26px 30px;
  }

  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }

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

  .page-about .coop-card--wide {
    grid-column: 1 / -1;
  }
}

/* ---------- 桌面 ---------- */

@media (min-width: 860px) {
  .page-about .about-hero {
    padding: 34px 0 48px;
  }

  .page-about .hero-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .codes-intro {
    grid-template-columns: 216px minmax(0, 1fr);
    gap: 28px;
    align-items: center;
  }

  .page-about .timeline {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
    padding-top: 34px;
  }

  .page-about .timeline::before {
    content: "";
    position: absolute;
    left: 8%;
    right: 8%;
    top: 12px;
    height: 2px;
    border-radius: 2px;
    background: linear-gradient(90deg, var(--turf), var(--turf-bright) 58%, var(--lime));
    opacity: 0.7;
  }

  .page-about .timeline-node::before {
    content: "";
    position: absolute;
    left: 24px;
    top: -25px;
    width: 12px;
    height: 12px;
    border: 3px solid var(--turf);
    border-radius: 50%;
    background: var(--ink-900);
  }

  .page-about .timeline-node:nth-child(2)::before {
    border-color: var(--turf-bright);
  }

  .page-about .timeline-node:nth-child(3)::before {
    border-color: var(--lime);
  }

  .page-about .code-cards {
    grid-template-columns: repeat(auto-fill, minmax(168px, 1fr));
    gap: 12px;
  }
}

@media (min-width: 1000px) {
  .page-about {
    padding-top: 112px;
    padding-bottom: 96px;
  }

  .page-about .about-grid {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: 44px;
  }

  .page-about .season-rail {
    position: sticky;
    top: 104px;
    grid-template-columns: minmax(0, 1fr);
    gap: 20px;
    padding: 22px 18px 22px 22px;
  }

  .page-about .season-rail::before {
    content: "";
    position: absolute;
    left: 0;
    top: 26px;
    bottom: 26px;
    width: 3px;
    border-radius: 3px;
    background: linear-gradient(180deg, var(--turf-bright), var(--lime) 58%, transparent);
    opacity: 0.55;
  }

  .page-about .about-stack {
    gap: 26px;
  }
}
<<<END>>>