.page-about {
  color: var(--text);
  padding-bottom: 64px;
}

.page-about .breadcrumb {
  padding-top: 18px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 26px;
  padding-block: 20px 34px;
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-size: clamp(38px, 10vw, 60px);
  font-weight: 800;
  line-height: 1.02;
  letter-spacing: -0.015em;
  color: var(--text);
}

.page-about .about-hero .lede {
  margin: 18px 0 0;
  max-width: 30em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

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

.page-about .about-hero__media {
  width: 100%;
}

.page-about .about-hero__media img,
.page-about .about-figure__media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .media-caption {
  margin: 10px 0 0;
  font-size: 12px;
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 数据条 ---------- */
.page-about .about-stats {
  list-style: none;
  margin: 4px 0 0;
  padding: 1px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: var(--rule);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 14px;
  background: var(--ink-900);
}

.page-about .about-stat__num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 5vw, 30px);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
  color: var(--lime);
}

.page-about .about-stat__label {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* ---------- 通用章节骨架 ---------- */
.page-about .about-section {
  display: grid;
  gap: 18px;
  margin-top: 54px;
}

.page-about .about-section h2,
.page-about .about-next h2 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(26px, 6vw, 40px);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .about-section__body p {
  margin: 0 0 14px;
  max-width: 36em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text);
}

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

.page-about .about-note {
  margin-top: 18px !important;
  max-width: 34em;
  padding-left: 14px;
  border-left: 2px solid var(--orange);
  font-size: 14px !important;
  line-height: 1.75 !important;
  color: var(--muted) !important;
}

/* ---------- 生产流程 ---------- */
.page-about .about-flow {
  list-style: none;
  margin: 20px 0 18px;
  padding: 0;
  border-top: var(--rule);
}

.page-about .about-flow__step {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 4px 12px;
  padding: 16px 0;
  border-bottom: var(--rule);
}

.page-about .about-flow__no {
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--orange);
}

.page-about .about-flow__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--text);
}

.page-about .about-flow__text {
  grid-column: 2;
  margin: 4px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 时间线 ---------- */
.page-about .about-tl {
  list-style: none;
  margin: 22px 0 0;
  padding: 0 0 0 24px;
  border-left: var(--rule);
}

.page-about .about-tl__item {
  position: relative;
  padding-bottom: 20px;
}

.page-about .about-tl__item::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 9px;
  width: 9px;
  height: 9px;
  background: var(--lime);
}

.page-about .about-tl__item--now::before {
  background: var(--orange);
}

.page-about .about-tl__details summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 12px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-tl__year {
  font-family: var(--font-mono);
  font-size: 15px;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.04em;
  color: var(--lime);
}

.page-about .about-tl__title {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  color: var(--text);
  transition: color 160ms var(--ease);
}

.page-about .about-tl__details summary:hover .about-tl__title {
  color: var(--lime-soft);
}

.page-about .about-tl__mark {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1;
  color: var(--muted);
}

.page-about .about-tl__mark::before {
  content: "+";
}

.page-about .about-tl__details[open] .about-tl__mark::before {
  content: "–";
}

.page-about .about-tl__details[open] .about-tl__title {
  color: var(--lime);
}

.page-about .about-tl__body {
  margin: 10px 0 0;
  max-width: 34em;
  font-size: 14px;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 图版 ---------- */
.page-about .about-figure {
  margin: 26px 0 0;
}

.page-about .about-figure__media {
  width: 100%;
}

/* ---------- CN 通道节点条 ---------- */
.page-about .about-channel__nodes {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-channel__node {
  flex: 1 1 132px;
  padding: 10px 12px;
  background: var(--ink-800);
  border-left: 2px solid var(--lg-blue);
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .about-channel__node:nth-child(2) {
  border-left-color: var(--lg-purple);
}

.page-about .about-channel__node:nth-child(3) {
  border-left-color: var(--lg-teal);
}

.page-about .about-channel__node--key {
  border-left-color: var(--lime);
  color: var(--lime);
}

/* ---------- 技能树 ---------- */
.page-about .about-tree {
  margin: 0 0 22px;
}

.page-about .about-tree__root {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  padding: 10px 16px;
  border: 1px solid var(--lime);
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--lime);
}

.page-about .about-tree__count {
  font-family: var(--font-mono);
  font-size: 22px;
  font-variant-numeric: tabular-nums;
}

.page-about .about-tree__branches {
  list-style: none;
  margin: 16px 0 0;
  padding: 0 0 0 18px;
  border-left: var(--rule);
}

.page-about .about-tree__branch {
  position: relative;
  padding-bottom: 18px;
}

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

.page-about .about-tree__branch::before {
  content: "";
  position: absolute;
  left: -18px;
  top: 9px;
  width: 12px;
  height: 1px;
  background: var(--line);
}

.page-about .about-tree__branch h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--text);
}

.page-about .about-tree__branch p {
  margin: 6px 0 0;
  max-width: 34em;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 暖纸档案 ---------- */
.page-about .about-archive {
  margin-top: 22px;
  padding: 24px 20px 28px;
}

.page-about .about-archive__head {
  margin: 0;
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: var(--paper-ink);
}

.page-about .about-archive__rows {
  margin: 18px 0 0;
  padding: 0;
}

.page-about .about-archive__row {
  display: grid;
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid rgba(23, 37, 29, 0.2);
}

.page-about .about-archive__row:last-child {
  padding-bottom: 0;
  border-bottom: none;
}

.page-about .about-archive__key {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: rgba(23, 37, 29, 0.62);
}

.page-about .about-archive__val {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--paper-ink);
}

.page-about .about-archive__num {
  font-family: var(--font-mono);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

/* ---------- 收尾入口 ---------- */
.page-about .about-next {
  margin-top: 58px;
  padding-top: 30px;
  border-top: var(--rule);
}

.page-about .about-next__list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-next__desc {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-stat {
    padding: 18px 16px;
  }

  .page-about .about-archive__row {
    grid-template-columns: 132px minmax(0, 1fr);
    align-items: baseline;
    gap: 0 18px;
  }

  .page-about .about-next__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px 24px;
  }
}

@media (min-width: 860px) {
  .page-about .breadcrumb {
    padding-top: 24px;
  }

  .page-about .about-hero {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
    gap: 48px;
    padding-block: 36px 48px;
  }

  .page-about .about-hero h1 {
    font-size: clamp(54px, 5.2vw, 76px);
  }

  .page-about .about-hero .lede {
    font-size: 17px;
    max-width: 28em;
  }

  .page-about .about-section {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: 44px;
    margin-top: 78px;
  }

  .page-about .about-section__head h2 {
    position: sticky;
    top: 88px;
  }

  .page-about .about-flow {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    margin-bottom: 22px;
  }

  .page-about .about-flow__step {
    grid-template-columns: minmax(0, 1fr);
    padding: 18px 18px 0;
    border-bottom: none;
    border-left: var(--rule);
  }

  .page-about .about-flow__step:first-child {
    padding-left: 0;
    border-left: none;
  }

  .page-about .about-flow__no {
    padding-top: 0;
  }

  .page-about .about-flow__text {
    grid-column: 1;
  }

  .page-about .about-tree__branches {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0 22px;
    padding: 18px 0 0;
    border-left: none;
    border-top: var(--rule);
  }

  .page-about .about-tree__branch {
    padding: 16px 0 0;
  }

  .page-about .about-tree__branch::before {
    left: 0;
    top: -18px;
    width: 1px;
    height: 16px;
  }

  .page-about .about-archive {
    padding: 32px 32px 36px;
  }

  .page-about .about-channel__nodes {
    gap: 10px;
  }

  .page-about .about-channel__node {
    flex: 1 1 0;
    min-width: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-tl__title {
    transition: none;
  }
}
<<<END>>>