.page-about {
  background: var(--ink);
  color: var(--paper);
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  padding-top: clamp(14px, 2.5vw, 26px);
  padding-bottom: clamp(40px, 6vw, 84px);
}

.page-about .about-frame {
  position: relative;
  border: 1px solid var(--line);
  background: var(--ink-2);
  padding: clamp(24px, 5vw, 68px);
  display: flex;
  align-items: flex-end;
  min-height: clamp(420px, 58vh, 560px);
}

.page-about .about-frame-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.page-about .about-frame-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 30%;
  filter: grayscale(1) contrast(1.08);
  opacity: 0.32;
}

.page-about .about-frame-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(11, 31, 26, 0.22) 0%, rgba(11, 31, 26, 0.74) 58%, rgba(11, 31, 26, 0.97) 100%);
}

.page-about .about-frame-inner {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 920px;
}

.page-about .about-hero-title {
  font-family: var(--font-narrow);
  font-size: clamp(36px, 7vw, 82px);
  line-height: 1;
  letter-spacing: 0.05em;
  margin: 14px 0 0;
  color: var(--paper);
}

.page-about .about-lede {
  margin-top: clamp(16px, 2.4vw, 26px);
  max-width: 46ch;
  color: rgba(216, 227, 222, 0.88);
}

.page-about .about-stats {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(18px, 3.5vw, 48px);
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: clamp(20px, 3vw, 28px) 0 0;
  border-top: 1px solid var(--line);
  list-style: none;
}

.page-about .about-stats li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 128px;
}

.page-about .about-stats .kpi {
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.6vw, 40px);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--pulse);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stats .kpi-label {
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--ash);
}

/* ---------- 浅色档案区 ---------- */
.page-about .about-paper {
  background: linear-gradient(180deg, var(--sheet) 0%, var(--sheet) 84%, var(--ink) 100%);
  color: var(--ink);
  padding-top: clamp(52px, 8vw, 112px);
  padding-bottom: clamp(88px, 13vw, 168px);
}

.page-about .about-head {
  display: flex;
  align-items: baseline;
  gap: clamp(14px, 2.4vw, 28px);
  margin-bottom: clamp(26px, 4vw, 46px);
}

.page-about .about-head .chapter-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--pulse);
}

.page-about .about-head .chapter-title {
  margin: 0;
  font-family: var(--font-narrow);
  font-size: clamp(24px, 3.4vw, 40px);
  line-height: 1.12;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .about-paper .about-head .chapter-num {
  color: var(--ink);
  opacity: 0.32;
}

.page-about .about-paper .about-head .chapter-title {
  color: var(--ink);
}

/* ---------- 01 起点 ---------- */
.page-about .about-from {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3.5vw, 44px);
}

.page-about .about-rail {
  display: flex;
  align-items: center;
  gap: 14px;
}

.page-about .about-rail-year {
  font-family: var(--font-mono);
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

.page-about .about-rail-line {
  width: 52px;
  height: 1px;
  background: linear-gradient(90deg, rgba(11, 31, 26, 0.45), rgba(11, 31, 26, 0));
}

.page-about .about-rail-note {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: rgba(11, 31, 26, 0.55);
  white-space: nowrap;
}

.page-about .about-from-text p {
  max-width: 56ch;
  margin: 0 0 clamp(14px, 2vw, 20px);
  line-height: 1.85;
  color: rgba(11, 31, 26, 0.82);
}

.page-about .about-index {
  margin-top: clamp(40px, 6vw, 76px);
}

.page-about .about-index-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid rgba(11, 31, 26, 0.18);
}

.page-about .about-index-title {
  margin: 0;
  font-family: var(--font-narrow);
  font-size: clamp(20px, 2.4vw, 26px);
  letter-spacing: 0.05em;
  color: var(--ink);
}

.page-about .about-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-filters .btn {
  font-size: 12px;
  padding: 6px 12px;
  letter-spacing: 0.06em;
}

.page-about .about-filters .btn-line {
  border: 1px solid rgba(11, 31, 26, 0.32);
  background: transparent;
  color: var(--ink);
}

.page-about .about-filters .btn-line[aria-pressed="true"] {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--pulse);
}

.page-about .about-filters .btn-ghost {
  border: 1px solid transparent;
  background: rgba(11, 31, 26, 0.07);
  color: rgba(11, 31, 26, 0.72);
}

.page-about .about-filters .btn-ghost:hover {
  background: rgba(11, 31, 26, 0.14);
}

.page-about .about-index-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(16px, 2.5vw, 24px);
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-index-card {
  padding: clamp(18px, 2.4vw, 26px);
  border: 1px solid rgba(11, 31, 26, 0.14);
  border-left: 3px solid var(--ink);
  background: rgba(255, 255, 255, 0.55);
}

.page-about .about-index-era {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

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

.page-about .about-index-card li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.72;
  color: rgba(11, 31, 26, 0.76);
}

.page-about .about-index-card li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 6px;
  height: 6px;
  background: var(--ink);
  opacity: 0.5;
  transform: rotate(45deg);
}

/* ---------- 02 使命 ---------- */
.page-about .about-mission-lede {
  max-width: 56ch;
  margin-bottom: clamp(28px, 4vw, 48px);
  color: rgba(216, 227, 222, 0.86);
}

.page-about .about-mission-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap);
}

.page-about .about-mission-item {
  padding-top: clamp(16px, 2vw, 22px);
  border-top: 2px solid var(--line);
}

.page-about .about-mission-item h3 {
  margin: 10px 0;
  font-family: var(--font-narrow);
  font-size: clamp(18px, 2vw, 22px);
  letter-spacing: 0.05em;
  color: var(--paper);
}

.page-about .about-mission-tag {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--pulse);
}

.page-about .about-mission-item p {
  max-width: 34ch;
  margin: 0;
  line-height: 1.82;
  color: rgba(216, 227, 222, 0.72);
}

.page-about .about-mission-grid > .about-mission-item:first-child {
  border-top-color: var(--pulse);
}

/* ---------- 03 生长 ---------- */
.page-about .about-build-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 56px);
}

.page-about .about-build-lede {
  max-width: 48ch;
  color: rgba(216, 227, 222, 0.86);
}

.page-about .about-steps {
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: clamp(18px, 2.4vw, 26px);
}

.page-about .about-steps li {
  padding-left: clamp(14px, 2vw, 22px);
  border-left: 2px solid var(--line);
}

.page-about .about-step-num {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--pulse);
}

.page-about .about-steps h3 {
  margin: 8px 0;
  font-family: var(--font-narrow);
  font-size: clamp(17px, 2vw, 20px);
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .about-steps p {
  max-width: 46ch;
  margin: 0;
  line-height: 1.8;
  color: rgba(216, 227, 222, 0.72);
}

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

/* ---------- 04 协作 ---------- */
.page-about .about-partners-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap);
}

.page-about .about-partner {
  position: relative;
  padding: clamp(20px, 2.6vw, 30px);
  background: var(--ink-2);
  border: 1px solid var(--line);
}

.page-about .about-partner::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 46px;
  height: 2px;
  background: var(--pulse);
}

.page-about .about-partner-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(34px, 4.6vw, 52px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--pulse);
  font-variant-numeric: tabular-nums;
}

.page-about .about-partner h3 {
  margin: 14px 0 10px;
  font-size: 16px;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .about-partner p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(216, 227, 222, 0.72);
}

.page-about .about-dict {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: clamp(16px, 2.5vw, 32px);
  margin-top: clamp(28px, 4vw, 48px);
  padding: clamp(22px, 3vw, 32px);
  border: 1px dashed var(--line);
}

.page-about .about-dict p {
  max-width: 62ch;
  margin: 0;
  line-height: 1.82;
  color: rgba(216, 227, 222, 0.78);
}

/* ---------- 时间轴视觉带 ---------- */
.page-about .about-arc {
  padding: clamp(24px, 4vw, 52px) 0;
}

.page-about .about-arc-inner {
  display: grid;
  grid-template-columns: 1fr;
  align-items: center;
  gap: clamp(20px, 3vw, 40px);
  padding: clamp(20px, 3vw, 40px);
  background: var(--ink-2);
  border: 1px solid var(--line);
}

.page-about .about-arc-media {
  height: 200px;
  overflow: hidden;
}

.page-about .about-arc-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: grayscale(1) contrast(1.05);
  opacity: 0.55;
}

.page-about .about-arc-quote {
  margin: 12px 0 0;
  max-width: 26ch;
  font-family: var(--font-narrow);
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.35;
  letter-spacing: 0.03em;
  color: var(--paper);
}

/* ---------- 05 里程碑 ---------- */
.page-about .about-milestones-lede {
  max-width: 56ch;
  margin-bottom: clamp(30px, 4.5vw, 52px);
  color: rgba(216, 227, 222, 0.86);
}

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

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--line) 0%, var(--pulse) 72%, var(--line) 100%);
}

.page-about .about-tl-item {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding-left: 34px;
  padding-bottom: clamp(20px, 3vw, 32px);
}

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  left: -2px;
  top: 8px;
  width: 11px;
  height: 11px;
  background: var(--ink);
  border: 2px solid var(--pulse);
  transform: rotate(45deg);
}

.page-about .about-tl-year {
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: clamp(15px, 1.8vw, 18px);
  letter-spacing: 0.04em;
  color: var(--ash);
  font-variant-numeric: tabular-nums;
}

.page-about .about-tl-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 0 0 14px;
  background: transparent;
  border: 0;
  border-bottom: 1px solid var(--line);
  color: var(--paper);
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition: color 0.2s ease;
}

.page-about .about-tl-trigger:hover {
  color: var(--pulse);
}

.page-about .about-tl-title {
  font-family: var(--font-narrow);
  font-size: clamp(17px, 2.1vw, 22px);
  line-height: 1.4;
  letter-spacing: 0.04em;
}

.page-about .about-tl-mark {
  flex: none;
  width: 10px;
  height: 10px;
  border-right: 1.5px solid var(--pulse);
  border-bottom: 1.5px solid var(--pulse);
  transform: rotate(45deg) translate(-2px, -2px);
  transition: transform 0.25s ease;
}

.page-about .about-tl-trigger[aria-expanded="true"] .about-tl-mark {
  transform: rotate(-135deg) translate(-2px, -2px);
}

.page-about .about-tl-panel {
  padding-top: 14px;
}

.page-about .about-tl-panel p {
  max-width: 54ch;
  margin: 0;
  line-height: 1.82;
  color: rgba(216, 227, 222, 0.74);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  padding: clamp(40px, 6vw, 72px) 0 clamp(56px, 8vw, 104px);
}

.page-about .about-cta-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: clamp(20px, 3vw, 44px);
  padding-top: clamp(24px, 3.5vw, 40px);
  border-top: 2px solid var(--pulse);
}

.page-about .about-cta-copy {
  max-width: 62ch;
}

.page-about .about-cta-title {
  margin: 10px 0;
  max-width: 24ch;
  font-family: var(--font-narrow);
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.28;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .about-cta-note {
  margin: 0;
  max-width: 46ch;
  line-height: 1.82;
  color: rgba(216, 227, 222, 0.74);
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 断点 ---------- */
@media (min-width: 720px) {
  .page-about .about-timeline::before {
    left: 96px;
  }

  .page-about .about-tl-item {
    grid-template-columns: 96px 1fr;
    gap: 28px;
    padding-left: 0;
  }

  .page-about .about-tl-item::before {
    left: 89px;
  }

  .page-about .about-tl-year {
    padding-right: 26px;
    text-align: right;
  }
}

@media (min-width: 780px) {
  .page-about .about-from {
    grid-template-columns: 168px 1fr;
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
  }

  .page-about .about-rail-line {
    width: 1px;
    height: 56px;
    background: linear-gradient(180deg, rgba(11, 31, 26, 0.45), rgba(11, 31, 26, 0));
  }

  .page-about .about-rail-note {
    white-space: normal;
    line-height: 1.6;
  }

  .page-about .about-arc-inner {
    grid-template-columns: 0.36fr 1fr;
    gap: clamp(24px, 4vw, 48px);
  }

  .page-about .about-arc-media {
    height: 340px;
  }
}

@media (min-width: 820px) {
  .page-about .about-mission-grid {
    grid-template-columns: 1.42fr 1fr 1fr;
    gap: clamp(20px, 3vw, 36px);
  }
}

@media (min-width: 840px) {
  .page-about .about-partners-grid {
    grid-template-columns: 1.2fr 1fr 1fr;
    align-items: start;
  }

  .page-about .about-index-list {
    grid-template-columns: 1.15fr 1fr 0.95fr;
  }
}

@media (min-width: 920px) {
  .page-about .about-build-grid {
    grid-template-columns: 1.12fr 0.88fr;
    align-items: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-tl-mark,
  .page-about .about-tl-trigger {
    transition: none;
  }
}
</main>
<<<END>>>