.page-about {
  --about-gap: clamp(18px, 3vw, 44px);
  --about-band: clamp(52px, 7vw, 100px);
  --about-rule: 1px solid var(--line-500);
  display: block;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding-block: clamp(16px, 2vw, 24px) 6px;
}

/* ---------- 封面 ---------- */
.page-about .cover {
  padding-bottom: clamp(36px, 5vw, 72px);
}

.page-about .cover-inner {
  display: grid;
  gap: clamp(20px, 3.4vw, 48px);
  align-items: end;
}

.page-about .cover-aside {
  display: flex;
  flex-direction: column;
  gap: 14px;
  align-items: flex-start;
}

.page-about .cover-lead h1 {
  margin: 0 0 clamp(14px, 2.2vw, 26px);
  font-family: var(--font-head);
  font-size: clamp(34px, 6.2vw, 74px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  font-weight: 700;
  color: var(--paper-050);
  max-width: 16ch;
}

.page-about .cover-lead .lead {
  margin: 0;
  max-width: 52ch;
  color: var(--paper-300);
  font-size: clamp(15px, 1.3vw, 18px);
  line-height: 1.85;
}

.page-about .cover-media {
  margin: 0;
}

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

/* ---------- 导览条 ---------- */
.page-about .toc {
  border-block: var(--about-rule);
}

.page-about .toc-list {
  display: flex;
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .toc-list > li {
  flex: 0 0 auto;
}

.page-about .toc-link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 15px 18px;
  border-right: var(--about-rule);
  color: var(--paper-300);
  text-decoration: none;
  font-size: 13px;
  white-space: nowrap;
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .toc-link:hover,
.page-about .toc-link:focus-visible {
  color: var(--lime-400);
  background: var(--ink-800);
  outline: none;
}

.page-about .toc-link:focus-visible {
  box-shadow: inset 0 0 0 2px var(--lime-400);
}

.page-about .toc-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--lime-400);
}

/* ---------- 通用带区 ---------- */
.page-about .band {
  padding-block: var(--about-band);
  border-bottom: var(--about-rule);
}

.page-about .band--last {
  border-bottom: 0;
}

.page-about .band-head {
  border-top: var(--about-rule);
  padding-top: clamp(16px, 2vw, 26px);
  margin-bottom: clamp(26px, 3.6vw, 48px);
  display: grid;
  gap: 12px;
}

.page-about .band-intro {
  margin: 0;
  max-width: 62ch;
  color: var(--paper-300);
  font-size: 16px;
  line-height: 1.85;
}

.page-about .band-head .section-title {
  margin: 0;
  color: var(--paper-050);
}

/* ---------- 起因 ---------- */
.page-about .origin-body {
  max-width: 74ch;
}

.page-about .origin-body p {
  margin: 0 0 1.35em;
  color: var(--paper-300);
  font-size: clamp(15px, 1.2vw, 17px);
  line-height: 1.95;
}

.page-about .origin-quote {
  margin: clamp(22px, 3vw, 38px) 0 0;
  padding: clamp(18px, 2.4vw, 28px) clamp(20px, 3vw, 36px);
  border-left: 3px solid var(--lime-400);
  background: var(--ink-800);
  font-family: var(--font-head);
  font-size: clamp(18px, 2.1vw, 24px);
  line-height: 1.6;
  color: var(--paper-050);
  letter-spacing: -0.01em;
}

/* ---------- 团队 ---------- */
.page-about .team-blocks {
  display: grid;
  gap: 1px;
  background: var(--line-500);
  border: var(--about-rule);
}

.page-about .team-block {
  background: var(--ink-800);
  padding: 0;
  transition: background var(--dur) var(--ease);
}

.page-about .team-block[open] {
  background: var(--indigo-700);
}

.page-about .team-block summary {
  list-style: none;
  cursor: pointer;
  padding: 20px 18px 18px;
  display: grid;
  gap: 6px;
}

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

.page-about .team-block summary:focus-visible {
  outline: 2px solid var(--lime-400);
  outline-offset: -4px;
}

.page-about .team-idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--lime-400);
}

.page-about .team-name {
  font-family: var(--font-head);
  font-size: 20px;
  font-weight: 700;
  color: var(--paper-050);
  letter-spacing: 0.02em;
}

.page-about .team-hint {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--paper-300);
}

.page-about .team-desc {
  margin: 0;
  padding: 0 18px 22px;
  color: var(--paper-300);
  font-size: 14px;
  line-height: 1.85;
}

/* ---------- 四个环节 ---------- */
.page-about .pipeline-layout {
  display: grid;
  gap: clamp(24px, 3.4vw, 48px);
}

.page-about .pipeline {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .pipe-step {
  display: grid;
  gap: 6px 24px;
  padding: 20px 0 20px 18px;
  border-top: var(--about-rule);
  position: relative;
}

.page-about .pipe-step:first-child {
  border-top: 0;
  padding-top: 4px;
}

.page-about .pipe-step::before {
  content: "";
  position: absolute;
  left: 0;
  top: 26px;
  width: 5px;
  height: 5px;
  background: var(--lime-400);
}

.page-about .pipe-step:nth-child(2)::before {
  background: var(--orange-500);
}

.page-about .pipe-step:nth-child(3)::before {
  background: var(--amber-600);
}

.page-about .pipe-step:nth-child(4)::before {
  background: var(--paper-300);
}

.page-about .pipe-time {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--lime-400);
  padding-top: 4px;
}

.page-about .pipe-title {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-size: 19px;
  font-weight: 700;
  color: var(--paper-050);
  letter-spacing: 0.02em;
}

.page-about .pipe-body p {
  margin: 0;
  color: var(--paper-300);
  font-size: 15px;
  line-height: 1.85;
}

.page-about .pipeline-media {
  margin: 0;
  align-self: start;
}

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

/* ---------- 指标切换 ---------- */
.page-about .metric-switch {
  display: grid;
  gap: 1px;
  background: var(--line-500);
  border: var(--about-rule);
  margin-top: clamp(28px, 4vw, 52px);
}

.page-about .metric-panel {
  background: var(--ink-900);
}

.page-about .metric-panel summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 16px 18px;
  color: var(--paper-050);
  font-size: 15px;
  font-weight: 500;
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease);
}

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

.page-about .metric-panel summary:hover,
.page-about .metric-panel summary:focus-visible {
  color: var(--lime-400);
  background: var(--ink-800);
  outline: none;
}

.page-about .metric-panel summary:focus-visible {
  box-shadow: inset 0 0 0 2px var(--lime-400);
}

.page-about .metric-panel[open] summary {
  color: var(--lime-400);
}

.page-about .metric-key {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--orange-500);
}

.page-about .metric-body {
  padding: 0 18px 20px;
}

.page-about .metric-body p {
  margin: 0;
  color: var(--paper-300);
  font-size: 14px;
  line-height: 1.9;
}

/* ---------- 年表 ---------- */
.page-about .timeline-media {
  margin: 0 0 1px;
}

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

.page-about .year-rail {
  display: flex;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--line-500);
  border: var(--about-rule);
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .year-rail > li {
  flex: 0 0 auto;
}

.page-about .year-node {
  display: grid;
  gap: 4px;
  min-width: 152px;
  padding: 16px 18px 14px;
  background: var(--ink-900);
  text-decoration: none;
  border-top: 2px solid transparent;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .year-node:hover,
.page-about .year-node:focus-visible {
  background: var(--ink-800);
  border-top-color: var(--lime-400);
  outline: none;
}

.page-about .year-node:focus-visible {
  box-shadow: inset 0 0 0 2px var(--lime-400);
}

.page-about .year-node-num {
  font-family: var(--font-mono);
  font-size: 26px;
  line-height: 1;
  color: var(--lime-400);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}

.page-about .year-node-label {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--paper-300);
}

.page-about .year-cards {
  display: grid;
  gap: 1px;
  margin-top: 1px;
  background: var(--line-500);
  border: var(--about-rule);
  border-top: 0;
}

.page-about .year-card {
  background: var(--ink-800);
  padding: 22px 20px 26px;
}

.page-about .year-card-num {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--orange-500);
}

.page-about .year-card-title {
  margin: 0 0 14px;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--paper-050);
  letter-spacing: 0.01em;
}

.page-about .year-card-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
}

.page-about .year-card-list li {
  position: relative;
  padding-left: 14px;
  color: var(--paper-300);
  font-size: 14px;
  line-height: 1.75;
}

.page-about .year-card-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 1px;
  background: var(--line-500);
}

/* ---------- 读者 ---------- */
.page-about .reader-rows {
  display: grid;
  gap: 1px;
  background: var(--line-500);
  border: var(--about-rule);
}

.page-about .reader-row {
  background: var(--ink-900);
  display: grid;
  gap: 8px;
  padding: 22px 18px 24px;
}

.page-about .reader-idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--lime-400);
}

.page-about .reader-title {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 700;
  color: var(--paper-050);
  letter-spacing: 0.01em;
}

.page-about .reader-body p {
  margin: 0;
  max-width: 68ch;
  color: var(--paper-300);
  font-size: 15px;
  line-height: 1.9;
}

.page-about .reader-body a {
  color: var(--lime-400);
  text-decoration: none;
  border-bottom: 1px solid var(--line-500);
}

.page-about .reader-body a:hover,
.page-about .reader-body a:focus-visible {
  border-bottom-color: var(--lime-400);
}

/* ---------- 数据来源 ---------- */
.page-about .source-body {
  display: grid;
  gap: clamp(24px, 3.4vw, 48px);
}

.page-about .source-text p {
  margin: 0 0 1.3em;
  color: var(--paper-300);
  font-size: 15.5px;
  line-height: 1.95;
}

.page-about .source-text a {
  color: var(--lime-400);
  text-decoration: none;
  border-bottom: 1px solid var(--line-500);
}

.page-about .source-text a:hover,
.page-about .source-text a:focus-visible {
  border-bottom-color: var(--lime-400);
}

.page-about .source-aside {
  display: grid;
  gap: 1px;
  background: var(--line-500);
  border: var(--about-rule);
  align-self: start;
}

.page-about .source-card {
  background: var(--ink-800);
  padding: 18px 18px 20px;
  display: grid;
  gap: 6px;
}

.page-about .source-num {
  font-family: var(--font-mono);
  font-size: clamp(36px, 5vw, 48px);
  line-height: 1;
  color: var(--lime-400);
  font-variant-numeric: tabular-nums;
}

.page-about .source-card--orange .source-num {
  color: var(--orange-500);
}

.page-about .source-label {
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--paper-300);
}

/* ---------- 覆盖与联络 ---------- */
.page-about .reach-stats {
  display: grid;
  gap: 1px;
  background: var(--line-500);
  border: var(--about-rule);
}

.page-about .reach-stat {
  background: var(--ink-800);
  padding: 24px 20px 26px;
  display: grid;
  gap: 8px;
}

.page-about .reach-num {
  font-family: var(--font-mono);
  font-size: clamp(38px, 5.6vw, 60px);
  line-height: 1;
  color: var(--lime-400);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
}

.page-about .reach-stat--orange .reach-num {
  color: var(--orange-500);
}

.page-about .reach-unit {
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  color: var(--paper-050);
  letter-spacing: 0.04em;
}

.page-about .reach-desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--paper-300);
}

.page-about .reach-contact {
  margin: clamp(28px, 4vw, 48px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--line-500);
  border: var(--about-rule);
}

.page-about .reach-contact-item {
  background: var(--ink-900);
  display: grid;
  gap: 4px;
  padding: 16px 18px;
}

.page-about .reach-contact-key {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--paper-300);
}

.page-about .reach-contact-val {
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--paper-050);
  word-break: break-word;
}

.page-about .reach-note {
  margin: 18px 0 0;
  max-width: 62ch;
  color: var(--paper-300);
  font-size: 14px;
  line-height: 1.85;
}

.page-about .reach-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 34px);
}

.page-about .reach-actions .btn {
  text-decoration: none;
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .pipe-step {
    grid-template-columns: minmax(0, 150px) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .reach-contact-item {
    grid-template-columns: minmax(0, 130px) minmax(0, 1fr);
    align-items: baseline;
    gap: 18px;
  }
}

@media (min-width: 760px) {
  .page-about .reader-row {
    grid-template-columns: 70px minmax(0, 1fr);
    align-items: start;
    padding: 26px 24px 28px;
  }

  .page-about .reader-idx {
    padding-top: 6px;
  }

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

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

  .page-about .metric-panel {
    border-right: 1px solid var(--line-500);
  }

  .page-about .metric-panel:last-child {
    border-right: 0;
  }
}

@media (min-width: 880px) {
  .page-about .pipeline-layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .source-body {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
  }
}

@media (min-width: 900px) {
  .page-about .cover-inner {
    grid-template-columns: minmax(0, 2.4fr) minmax(0, 5.6fr) minmax(0, 4fr);
    gap: clamp(24px, 3.2vw, 56px);
  }

  .page-about .team-blocks {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .year-cards {
    grid-template-columns: 1.25fr 1fr 1.15fr 0.9fr 1.1fr;
  }

  .page-about .year-card {
    padding: 26px 22px 30px;
  }
}

@media (min-width: 1080px) {
  .page-about .reader-rows {
    border-left: 0;
    border-right: 0;
  }
}
<<<END>>>