.page-about {
  --about-rule: 1px solid rgba(169, 184, 199, 0.18);
  --about-paper-muted: #3b4d5f;
  --about-paper-line: rgba(18, 34, 51, 0.14);
  --about-deep-cyan: #0e6b60;
  background: var(--ink);
  color: var(--white);
}

/* ---------- Hero ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(24px, 6vw, 58px) 0 clamp(34px, 6vw, 68px);
  background:
    radial-gradient(120% 95% at 8% 0%, rgba(34, 240, 211, 0.1), transparent 58%),
    radial-gradient(90% 80% at 100% 10%, rgba(255, 122, 61, 0.08), transparent 62%),
    linear-gradient(180deg, rgba(11, 29, 51, 0.92), var(--ink) 74%);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 3px;
  background: linear-gradient(90deg, var(--cyan), var(--orange) 48%, rgba(34, 240, 211, 0) 92%);
  opacity: 0.9;
}

.page-about .about-hero__inner {
  position: relative;
}

.page-about .about-hero .breadcrumbs {
  font-size: 0.78rem;
  color: var(--mist);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(26px, 5vw, 46px);
  margin-top: clamp(20px, 3.5vw, 34px);
}

.page-about h1 {
  margin: 0.35em 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.9rem, 5.6vw, 3.5rem);
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--white);
  max-width: 16em;
}

.page-about .about-hero__intro {
  margin: clamp(14px, 2.4vw, 20px) 0 0;
  max-width: 34em;
  font-size: clamp(15px, 2.4vw, 17px);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(20px, 3vw, 28px);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: rgba(169, 184, 199, 0.16);
  border: 1px solid rgba(169, 184, 199, 0.2);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-hero__stats > div {
  background: var(--cabin);
  padding: 14px 16px 16px;
}

.page-about .about-hero__stats dt {
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .about-hero__stats dd {
  margin: 6px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(1.3rem, 3.6vw, 1.6rem);
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
  line-height: 1;
}

.page-about .about-hero__unit {
  font-size: 0.66em;
  margin-left: 2px;
  color: var(--sage);
}

/* ---------- Body layout ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(22px, 4vw, 40px);
  padding-top: clamp(28px, 5vw, 56px);
  padding-bottom: clamp(46px, 7vw, 88px);
}

/* ---------- Rail (chapter index) ---------- */
.page-about .about-rail__title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-rail__list {
  list-style: none;
  display: flex;
  gap: 8px;
  margin: 0.7em 0 0;
  padding: 0 0 4px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__list a {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
  padding: 7px 12px;
  border: 1px solid rgba(169, 184, 199, 0.24);
  border-radius: 999px;
  color: var(--mist);
  font-size: 0.8rem;
  text-decoration: none;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .about-rail__list .num {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--sage);
}

.page-about .about-rail__list a:hover,
.page-about .about-rail__list a:focus-visible {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}

.page-about .about-rail__list a:hover .num,
.page-about .about-rail__list a:focus-visible .num {
  color: var(--ink);
}

/* ---------- Chapters ---------- */
.page-about .about-chapter {
  position: relative;
  padding-top: clamp(28px, 4vw, 44px);
  padding-bottom: clamp(28px, 4.4vw, 50px);
  border-top: var(--about-rule);
}

.page-about .about-flow > .about-chapter:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .about-chapter__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(2.5rem, 8vw, 4.2rem);
  line-height: 0.9;
  letter-spacing: 0.02em;
  color: rgba(34, 240, 211, 0.18);
  -webkit-text-stroke: 1px rgba(34, 240, 211, 0.55);
  margin-bottom: 0.28em;
}

.page-about .about-chapter h2 {
  margin: 0 0 0.55em;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.4rem, 3.8vw, 2.1rem);
  line-height: 1.26;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-chapter p {
  margin: 0 0 0.95em;
  max-width: 44em;
  font-size: clamp(15px, 2.3vw, 16.5px);
  line-height: 1.85;
  color: var(--mist);
}

/* ---------- Method ---------- */
.page-about .about-method {
  display: grid;
  gap: clamp(18px, 3vw, 28px);
  margin-top: clamp(16px, 2.6vw, 24px);
}

.page-about .about-dims {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: rgba(169, 184, 199, 0.16);
  border: 1px solid rgba(169, 184, 199, 0.16);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-dims li {
  display: grid;
  gap: 4px;
  padding: 13px 16px 15px;
  background: var(--cabin);
}

.page-about .about-dims strong {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--white);
  letter-spacing: 0.01em;
}

.page-about .about-dims span {
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-model {
  display: block;
  width: 100%;
  height: auto;
  padding: 10px;
  background: var(--cabin);
  border: 1px solid rgba(169, 184, 199, 0.2);
  border-radius: var(--radius);
}

.page-about .about-model text {
  font-family: var(--font-body);
  font-size: 13px;
  fill: var(--mist);
}

.page-about .about-model__box {
  fill: rgba(6, 17, 31, 0.6);
  stroke: rgba(127, 169, 155, 0.45);
  stroke-width: 1;
}

.page-about .about-model__flow {
  fill: none;
  stroke: rgba(34, 240, 211, 0.4);
  stroke-width: 1.2;
}

.page-about .about-model__out {
  fill: rgba(34, 240, 211, 0.1);
  stroke: var(--cyan);
  stroke-width: 1.2;
}

.page-about .about-model__num {
  font-family: var(--font-mono);
  font-size: 24px;
  fill: var(--cyan);
}

.page-about .about-clock {
  list-style: none;
  display: grid;
  gap: 8px;
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 0;
}

.page-about .about-clock li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
  padding: 10px 14px;
  border-left: 2px solid var(--orange);
  background: rgba(255, 122, 61, 0.07);
  border-radius: 0 10px 10px 0;
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-clock .num {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  color: var(--orange);
  letter-spacing: 0.04em;
}

/* ---------- Figures ---------- */
.page-about .figure {
  margin: clamp(18px, 3vw, 28px) 0 0;
}

/* ---------- Paper chapter ---------- */
.page-about .about-paper {
  margin-block: clamp(10px, 2vw, 18px);
  padding: clamp(22px, 4.4vw, 42px);
  border-top: 0;
  border-radius: var(--radius-paper);
  background: var(--paper);
  color: var(--paper-ink);
}

.page-about .about-paper h2 {
  color: var(--paper-ink);
}

.page-about .about-paper p {
  color: var(--about-paper-muted);
}

.page-about .about-paper .about-chapter__num {
  color: rgba(18, 34, 51, 0.08);
  -webkit-text-stroke: 1px rgba(18, 34, 51, 0.42);
}

.page-about .about-paper .figure__cap {
  color: #4a5c6d;
}

.page-about .about-team {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: clamp(16px, 3vw, 26px) 0;
  padding: 0;
}

.page-about .about-team li {
  display: grid;
  gap: 3px;
  padding: 13px 13px 15px;
  background: rgba(18, 34, 51, 0.06);
  border: 1px solid var(--about-paper-line);
  border-radius: 14px;
  transition: background 0.2s var(--ease), transform 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-team li:hover,
.page-about .about-team li:focus-within {
  background: rgba(18, 34, 51, 0.11);
  border-color: rgba(14, 107, 96, 0.45);
  transform: translateY(-2px);
}

.page-about .about-team__num {
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 4.4vw, 1.85rem);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--about-deep-cyan);
}

.page-about .about-team strong {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--paper-ink);
}

.page-about .about-team__note {
  font-size: 0.78rem;
  line-height: 1.6;
  color: #4d5f70;
}

/* ---------- Timeline ---------- */
.page-about .about-timeline {
  display: grid;
  gap: 10px;
  margin-top: clamp(18px, 3vw, 28px);
  padding-left: clamp(16px, 3vw, 26px);
  border-left: 1px solid rgba(169, 184, 199, 0.34);
}

.page-about .about-node {
  position: relative;
  padding: 0 14px;
  background: var(--cabin);
  border: 1px solid rgba(169, 184, 199, 0.18);
  border-radius: 14px;
  transition: border-color 0.2s var(--ease);
}

.page-about .about-node::before {
  content: "";
  position: absolute;
  top: 19px;
  left: calc(-1 * clamp(16px, 3vw, 26px) - 5px);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(34, 240, 211, 0.16);
}

.page-about .about-node[open] {
  border-color: rgba(34, 240, 211, 0.42);
}

.page-about .about-node summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  padding: 13px 2px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-node__year {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  letter-spacing: 0.04em;
  color: var(--cyan);
}

.page-about .about-node__title {
  font-size: 0.96rem;
  font-weight: 600;
  color: var(--white);
}

.page-about .about-node summary::after {
  content: "展开";
  margin-left: auto;
  padding: 2px 9px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--mist);
  border: 1px solid rgba(169, 184, 199, 0.28);
  border-radius: 999px;
}

.page-about .about-node[open] summary::after {
  content: "收起";
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}

.page-about .about-node p {
  margin: 0 0 14px;
  padding-right: 6px;
  font-size: 0.9rem;
  line-height: 1.8;
}

/* ---------- Coverage & contact ---------- */
.page-about .about-reach {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: clamp(16px, 3vw, 26px) 0;
}

.page-about .about-reach > div {
  display: grid;
  gap: 4px;
  padding: 14px 15px 16px;
  background: var(--cabin);
  border: 1px solid rgba(169, 184, 199, 0.18);
  border-radius: 14px;
}

.page-about .about-reach__num {
  font-family: var(--font-mono);
  font-size: clamp(1.4rem, 4vw, 1.75rem);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
}

.page-about .about-reach__unit {
  font-size: 0.62em;
  margin-left: 2px;
  color: var(--sage);
}

.page-about .about-reach__label {
  font-size: 0.8rem;
  color: var(--mist);
}

.page-about .about-contact {
  margin-top: clamp(22px, 3.4vw, 34px);
  padding: clamp(20px, 4vw, 34px);
  border: 1px solid rgba(169, 184, 199, 0.3);
  border-radius: var(--radius-lg);
  background: linear-gradient(140deg, rgba(34, 240, 211, 0.09), rgba(11, 29, 51, 0.94) 56%);
}

.page-about .about-contact h3 {
  margin: 0 0 0.35em;
  font-family: var(--font-display);
  font-size: clamp(1.1rem, 2.8vw, 1.35rem);
  font-weight: 800;
  color: var(--white);
}

.page-about .about-contact__tip {
  margin: 0 0 1.2em;
  font-size: 0.86rem;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-contact__list {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  background: rgba(169, 184, 199, 0.16);
  border: 1px solid rgba(169, 184, 199, 0.16);
  border-radius: 14px;
  overflow: hidden;
}

.page-about .about-contact__list > div {
  display: grid;
  gap: 3px;
  padding: 12px 15px;
  background: rgba(6, 17, 31, 0.55);
}

.page-about .about-contact__list dt {
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  color: var(--sage);
}

.page-about .about-contact__list dd {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.6;
  color: var(--white);
  word-break: break-word;
}

.page-about .about-contact__list dd.num {
  font-family: var(--font-mono);
  letter-spacing: 0.03em;
}

.page-about .about-contact__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(16px, 2.6vw, 22px);
}

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

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

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

@media (min-width: 760px) {
  .page-about .about-team {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .about-clock li {
    flex-direction: column;
    gap: 4px;
  }
}

@media (min-width: 900px) {
  .page-about .about-method {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(250px, 0.8fr);
    align-items: end;
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: 188px minmax(0, 1fr);
    gap: clamp(32px, 4vw, 56px);
  }

  .page-about .about-rail {
    position: sticky;
    top: 96px;
    align-self: start;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
    border-left: 1px solid rgba(169, 184, 199, 0.24);
  }

  .page-about .about-rail__list a {
    margin-left: -1px;
    padding: 9px 0 9px 14px;
    border: 0;
    border-left: 2px solid transparent;
    border-radius: 0;
    white-space: normal;
  }

  .page-about .about-rail__list a:hover,
  .page-about .about-rail__list a:focus-visible {
    background: none;
    border-left-color: var(--cyan);
    color: var(--cyan);
  }

  .page-about .about-rail__list a:hover .num,
  .page-about .about-rail__list a:focus-visible .num {
    color: var(--cyan);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__list a,
  .page-about .about-team li,
  .page-about .about-node {
    transition: none;
  }

  .page-about .about-team li:hover,
  .page-about .about-team li:focus-within {
    transform: none;
  }
}
<<<END>>>