.page-about {
  position: relative;
  padding-bottom: clamp(2rem, 6vw, 4rem);
  background-color: var(--ink-900);
}

.page-about::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 860px;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(34, 48, 79, 0.55) 1px, transparent 1px),
    linear-gradient(90deg, rgba(34, 48, 79, 0.38) 1px, transparent 1px);
  background-size: 88px 88px;
  -webkit-mask-image: linear-gradient(to bottom, #000 0%, transparent 100%);
  mask-image: linear-gradient(to bottom, #000 0%, transparent 100%);
  opacity: 0.42;
  z-index: 0;
}

.page-about > * {
  position: relative;
  z-index: 1;
}

.page-about .breadcrumbs {
  padding-top: clamp(1rem, 3vw, 1.75rem);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--text-300);
}

.page-about .breadcrumbs a {
  color: var(--text-300);
  text-decoration: none;
}

.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--cool-400);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(1.5rem, 4vw, 2.5rem) 0 clamp(2.5rem, 6vw, 4rem);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
}

.page-about .about-hero__lead .eyebrow {
  margin: 0 0 0.9rem;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--pulse-500);
}

.page-about .about-hero h1 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2rem, 7vw, 3.75rem);
  line-height: 1.08;
  letter-spacing: -0.01em;
  font-weight: 700;
  color: var(--text-100);
  text-wrap: balance;
}

.page-about .about-hero__intro {
  margin: clamp(1rem, 3vw, 1.5rem) 0 0;
  max-width: 62ch;
  font-size: clamp(1rem, 2.2vw, 1.125rem);
  line-height: 1.8;
  color: var(--text-300);
}

.page-about .about-hero__facts {
  border: 1px solid var(--line-600);
  border-left: 3px solid var(--cool-400);
  background: var(--ink-800);
  box-shadow: var(--shadow-hard);
  padding: 1rem 1.1rem 0.35rem;
}

.page-about .about-hero__facts-label {
  display: block;
  margin: 0 0 0.75rem;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--text-300);
}

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

.page-about .about-facts__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--line-600);
}

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

.page-about .about-facts dt {
  font-size: 0.8125rem;
  color: var(--text-300);
}

.page-about .about-facts dd {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.25rem, 3.4vw, 1.6rem);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--text-100);
}

.page-about .about-facts__row:nth-child(odd) dd {
  color: var(--cool-400);
}

.page-about .about-facts__row:nth-child(even) dd {
  color: var(--pulse-500);
}

/* 顶部赛季刻度尺 */
.page-about .season-ruler {
  display: flex;
  gap: 0.75rem 2rem;
  margin: clamp(1.75rem, 5vw, 3rem) 0 0;
  padding: 0.85rem 0;
  list-style: none;
  border-top: 1px solid var(--line-600);
  border-bottom: 1px solid var(--line-600);
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .season-ruler__item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  white-space: nowrap;
  font-size: 0.8125rem;
  color: var(--text-300);
}

.page-about .season-ruler__idx {
  font-size: 11px;
  letter-spacing: 0.12em;
  padding: 2px 7px;
  border: 1px solid var(--line-600);
  color: var(--violet-500);
}

.page-about .season-ruler__item:nth-child(2) .season-ruler__idx {
  color: var(--cool-400);
}

.page-about .season-ruler__item:nth-child(3) .season-ruler__idx {
  color: var(--warm-400);
}

/* ---------- 主体双栏 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(2rem, 5vw, 3rem);
  padding-top: clamp(2.5rem, 6vw, 4.5rem);
}

.page-about .about-index {
  border: 1px solid var(--line-600);
  background: var(--ink-800);
  padding: 1rem 1.1rem;
}

.page-about .about-index__label {
  margin: 0 0 0.75rem;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--text-300);
}

.page-about .about-index__list {
  display: flex;
  gap: 0.85rem 1.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-index__item {
  flex: 0 0 auto;
}

.page-about .about-index__item a {
  display: inline-flex;
  align-items: baseline;
  gap: 0.45rem;
  padding: 0.2rem 0;
  font-size: 0.875rem;
  color: var(--text-300);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-index__item a:hover,
.page-about .about-index__item a:focus-visible {
  color: var(--text-100);
  border-bottom-color: var(--pulse-500);
}

.page-about .about-index__num {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--cool-400);
}

/* ---------- 章节 ---------- */
.page-about .about-chapters {
  display: grid;
  gap: 0;
}

.page-about .chapter {
  padding-bottom: clamp(2.25rem, 6vw, 4rem);
  border-bottom: 1px solid var(--line-600);
  scroll-margin-top: 5rem;
}

.page-about .chapter + .chapter {
  padding-top: clamp(2.25rem, 6vw, 4rem);
}

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

.page-about .chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.5rem 1rem;
  align-items: baseline;
  margin-bottom: 1.25rem;
}

.page-about .chapter__num {
  font-family: var(--font-display);
  font-size: clamp(2.25rem, 8vw, 3.75rem);
  font-weight: 700;
  line-height: 0.82;
  font-variant-numeric: tabular-nums;
  color: var(--cool-400);
  opacity: 0.85;
}

.page-about .chapter--pulse .chapter__num {
  color: var(--pulse-500);
}

.page-about .chapter--warm .chapter__num {
  color: var(--warm-400);
}

.page-about .chapter--violet .chapter__num {
  color: var(--violet-500);
}

.page-about .chapter__head h2 {
  margin: 0;
  font-size: clamp(1.4rem, 4vw, 1.9rem);
  line-height: 1.3;
  font-weight: 700;
  color: var(--text-100);
}

.page-about .chapter__body > p {
  margin: 0 0 1.1rem;
  max-width: 72ch;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--text-300);
}

.page-about .chapter__body strong {
  color: var(--text-100);
  font-weight: 600;
}

.page-about .key-figure {
  font-family: var(--font-display);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: 1.12em;
  color: var(--pulse-500);
}

.page-about .chapter__more {
  margin-top: 1.4rem !important;
  padding-top: 0.9rem;
  border-top: 1px dashed var(--line-600);
  font-size: 0.9375rem !important;
}

.page-about .chapter__body a {
  color: var(--cool-400);
  text-decoration: none;
  border-bottom: 1px solid rgba(36, 211, 255, 0.35);
}

.page-about .chapter__body a:hover,
.page-about .chapter__body a:focus-visible {
  color: var(--pulse-500);
  border-bottom-color: var(--pulse-500);
}

/* 图片 */
.page-about .figure {
  margin: 1.6rem 0 1.8rem;
}

.page-about .figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line-600);
  background: var(--ink-800);
  object-fit: cover;
}

.page-about .figure figcaption {
  margin-top: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  line-height: 1.6;
  color: var(--text-300);
}

/* 时间线 */
.page-about .timeline {
  list-style: none;
  margin: 1.6rem 0 0;
  padding: 0 0 0 1.75rem;
  border-left: 1px solid var(--line-600);
  display: grid;
  gap: 1.9rem;
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -2.36rem;
  top: 0.42rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cool-400);
  box-shadow: 0 0 0 3px rgba(36, 211, 255, 0.16);
}

.page-about .timeline__item:nth-child(2)::before {
  background: var(--violet-500);
  box-shadow: 0 0 0 3px rgba(122, 92, 255, 0.16);
}

.page-about .timeline__item:nth-child(3)::before {
  background: var(--warm-400);
  box-shadow: 0 0 0 3px rgba(255, 138, 61, 0.16);
}

.page-about .timeline__stage {
  display: inline-block;
  margin-bottom: 0.5rem;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--text-300);
}

.page-about .timeline__item h3 {
  margin: 0 0 0.5rem;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--text-100);
}

.page-about .timeline__item p {
  margin: 0;
  max-width: 68ch;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--text-300);
}

/* 引用 */
.page-about .pull-quote {
  margin: 1.8rem 0;
  padding: 0.4rem 0 0.4rem 1.1rem;
  border-left: 3px solid var(--warm-400);
  font-size: 1.0625rem;
  line-height: 1.75;
  color: var(--text-100);
}

.page-about .pull-quote cite {
  display: block;
  margin-top: 0.5rem;
  font-family: var(--font-mono);
  font-style: normal;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--text-300);
}

/* 团队折叠 */
.page-about .team-folds {
  margin: 1.6rem 0;
  display: grid;
  gap: 0.75rem;
}

.page-about .team-fold {
  border: 1px solid var(--line-600);
  background: var(--ink-800);
}

.page-about .team-fold[open] {
  border-left: 3px solid var(--cool-400);
  box-shadow: var(--shadow-hard);
}

.page-about .team-fold__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.95rem 1.1rem;
  cursor: pointer;
  list-style: none;
  color: var(--text-100);
}

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

.page-about .team-fold__summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--cool-400);
}

.page-about .team-fold[open] .team-fold__summary::after {
  content: "−";
}

.page-about .team-fold__name {
  font-size: 1rem;
  font-weight: 600;
}

.page-about .team-fold__count {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--pulse-500);
  margin-left: auto;
  padding-right: 0.35rem;
}

.page-about .team-fold__body {
  padding: 0 1.1rem 1.1rem;
}

.page-about .team-fold__body ul {
  margin: 0;
  padding-left: 1.1rem;
  display: grid;
  gap: 0.5rem;
}

.page-about .team-fold__body li {
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--text-300);
}

/* 承诺列表 */
.page-about .promise-list {
  list-style: none;
  margin: 0.5rem 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line-600);
  border: 1px solid var(--line-600);
  counter-reset: promise;
}

.page-about .promise {
  background: var(--ink-800);
  padding: 1.25rem 1.2rem;
  counter-increment: promise;
}

.page-about .promise h3 {
  position: relative;
  margin: 0 0 0.6rem;
  padding-left: 2.1rem;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--text-100);
}

.page-about .promise h3::before {
  content: "0" counter(promise);
  position: absolute;
  left: 0;
  top: 0.1em;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--pulse-500);
}

.page-about .promise p {
  margin: 0;
  padding-left: 2.1rem;
  max-width: 66ch;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--text-300);
}

/* ---------- 底部 CTA ---------- */
.page-about .about-cta {
  margin-top: clamp(2.5rem, 6vw, 4.5rem);
  border-top: 1px solid var(--line-600);
  border-bottom: 1px solid var(--line-600);
  background: linear-gradient(120deg, rgba(36, 211, 255, 0.08), rgba(122, 92, 255, 0.1) 55%, rgba(255, 138, 61, 0.08));
}

.page-about .about-cta__inner {
  display: grid;
  gap: 1.5rem;
  padding-top: clamp(2rem, 5vw, 3rem);
  padding-bottom: clamp(2rem, 5vw, 3rem);
}

.page-about .about-cta h2 {
  margin: 0 0 0.6rem;
  font-size: clamp(1.3rem, 3.6vw, 1.7rem);
  color: var(--text-100);
}

.page-about .about-cta p {
  margin: 0;
  max-width: 56ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--text-300);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(280px, 0.85fr);
    align-items: end;
    gap: clamp(2.5rem, 5vw, 4rem);
  }

  .page-about .season-ruler {
    overflow-x: visible;
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: 216px minmax(0, 1fr);
    gap: clamp(2.5rem, 5vw, 4.5rem);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 1.5rem;
  }

  .page-about .about-index__list {
    flex-direction: column;
    gap: 0.15rem;
    overflow-x: visible;
  }

  .page-about .about-index__item a {
    display: flex;
    width: 100%;
    justify-content: flex-start;
  }

  .page-about .chapter__head {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.35rem;
  }

  .page-about .chapter__num {
    font-size: clamp(2.5rem, 4.2vw, 3.4rem);
  }
}

@media (min-width: 1280px) {
  .page-about .chapter__head {
    grid-template-columns: 4.6rem minmax(0, 1fr);
    gap: 0.75rem 1.25rem;
    align-items: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__item a,
  .page-about .chapter__body a {
    transition: none;
  }
}
</final>