.page-about {
  background: var(--c-abyss);
  color: var(--c-mist);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(40px, 7vw, 88px) 0 clamp(44px, 7vw, 92px);
  border-bottom: 1px solid var(--c-hairline-soft);
  background:
    radial-gradient(120% 90% at 84% 6%, rgba(123, 92, 255, .30), transparent 58%),
    radial-gradient(90% 74% at 6% 0%, rgba(53, 224, 224, .18), transparent 62%),
    var(--c-abyss);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(159, 184, 200, .07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(159, 184, 200, .07) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, .55), transparent 78%);
}

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

.page-about .about-hero .breadcrumb {
  margin-bottom: clamp(20px, 3vw, 34px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(18px, 3vw, 30px);
}

.page-about .about-hero__mark {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-family: var(--font-num);
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--c-mist);
  text-transform: uppercase;
}

.page-about .about-hero__mark-sq {
  width: 12px;
  height: 12px;
  border-radius: 3px;
  background: var(--c-cyan);
  box-shadow: 0 0 0 4px rgba(53, 224, 224, .16);
}

.page-about .about-hero__copy .eyebrow {
  color: var(--c-cyan);
}

.page-about .about-hero__copy h1 {
  margin: .35em 0 .6em;
  font-family: var(--font-head);
  font-size: clamp(2rem, 5.6vw, 3.9rem);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -.015em;
  color: var(--c-paper);
  max-width: 22ch;
}

.page-about .about-hero__copy .lead {
  max-width: 46rem;
  margin: 0;
  font-size: clamp(1rem, 1.6vw, 1.0625rem);
  line-height: 1.85;
  color: var(--c-mist);
}

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

@media (min-width: 1000px) {
  .page-about .about-hero__grid {
    grid-template-columns: 168px minmax(0, 1fr);
    align-items: start;
  }
  .page-about .about-hero__mark {
    padding-top: .9em;
  }
}

/* ---------- 正文骨架：左侧索引 + 右侧堆叠面板 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(22px, 3vw, 44px);
  padding-top: clamp(34px, 5vw, 64px);
  padding-bottom: clamp(52px, 8vw, 104px);
}

.page-about .about-rail {
  position: relative;
  min-width: 0;
}

.page-about .about-rail__title {
  margin: 0 0 10px;
  font-family: var(--font-num);
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .2em;
  color: var(--c-mist);
  text-transform: uppercase;
}

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

.page-about .about-rail__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 14px;
  white-space: nowrap;
  font-size: .875rem;
  font-weight: 500;
  color: var(--c-mist);
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: var(--r-pill);
  transition: color .2s ease, border-color .2s ease, background-color .2s ease;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--c-cyan);
  border-color: var(--c-hairline);
}

.page-about .about-rail__link[aria-current] {
  color: var(--c-cyan);
  border-color: var(--c-cyan);
  background: rgba(53, 224, 224, .12);
}

.page-about .about-rail__no {
  font-family: var(--font-num);
  font-size: .75rem;
  font-weight: 900;
  color: var(--c-violet);
}

@media (min-width: 1000px) {
  .page-about .about-body {
    grid-template-columns: 168px minmax(0, 1fr);
    align-items: start;
  }
  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
  }
  .page-about .about-rail__list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }
  .page-about .about-rail__link {
    border-radius: var(--r-md);
  }
}

.page-about .about-panels {
  min-width: 0;
}

/* ---------- 面板基类 ---------- */
.page-about .panel {
  position: relative;
  margin-bottom: clamp(24px, 3.6vw, 48px);
  padding: clamp(26px, 4vw, 54px);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-panel);
}

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

.page-about .panel--deep {
  background: linear-gradient(158deg, var(--c-deep) 0%, #06182A 100%);
  border: 1px solid var(--c-hairline);
  color: var(--c-mist);
}

.page-about .panel--paper {
  background: var(--c-paper);
  border: 1px solid rgba(10, 20, 32, .08);
  color: var(--c-ink);
}

.page-about .panel__no {
  display: block;
  margin-bottom: .35em;
  font-family: var(--font-num);
  font-size: clamp(2rem, 4.4vw, 3rem);
  font-weight: 900;
  line-height: 1;
  letter-spacing: .02em;
  color: var(--c-cyan);
  opacity: .6;
}

.page-about .panel--paper .panel__no {
  color: var(--c-violet-ink);
  opacity: .78;
}

.page-about .panel h2 {
  margin: 0 0 .7em;
  font-family: var(--font-head);
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 900;
  line-height: 1.28;
  letter-spacing: -.01em;
  max-width: 24ch;
}

.page-about .panel--deep h2 {
  color: var(--c-paper);
}

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

.page-about .panel .prose {
  max-width: 44rem;
}

.page-about .panel--deep .prose p,
.page-about .panel--deep p {
  color: var(--c-mist);
}

.page-about .panel--paper .prose p,
.page-about .panel--paper p {
  color: var(--c-ink);
}

.page-about .panel .prose p {
  margin: 0 0 1.05em;
  line-height: 1.85;
}

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

.page-about .panel__intro {
  max-width: 40rem;
  margin: 0 0 clamp(20px, 3vw, 32px);
  line-height: 1.8;
}

.page-about .panel__foot {
  margin: clamp(20px, 3vw, 30px) 0 0;
  font-size: .9375rem;
}

.page-about .about-link {
  color: var(--c-cyan);
  font-weight: 700;
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 224, .45);
  transition: border-color .2s ease;
}

.page-about .panel--paper .about-link {
  color: var(--c-violet-ink);
  border-bottom-color: rgba(86, 56, 214, .4);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  border-bottom-color: currentColor;
}

.page-about figure.media-frame {
  margin: 0;
}

@media (min-width: 900px) {
  .page-about .about-panels .panel:nth-child(odd) {
    margin-right: clamp(0px, 3vw, 48px);
  }
  .page-about .about-panels .panel:nth-child(even) {
    margin-left: clamp(0px, 3vw, 48px);
  }
}

/* ---------- 规模数字 ---------- */
.page-about .stat-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(12px, 2vw, 20px);
  margin-bottom: clamp(22px, 3vw, 34px);
}

.page-about .stat {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0 6px;
  padding: clamp(14px, 2vw, 22px);
  border-radius: var(--r-md);
  background: rgba(7, 27, 47, .055);
  border: 1px solid rgba(10, 20, 32, .12);
}

.page-about .stat__num {
  font-family: var(--font-num);
  font-size: clamp(1.9rem, 4.4vw, 2.75rem);
  font-weight: 900;
  line-height: 1;
  color: var(--c-cyan-ink);
}

.page-about .stat__unit {
  font-size: .875rem;
  font-weight: 700;
  color: var(--c-violet-ink);
}

.page-about .stat__label {
  flex: 1 0 100%;
  margin-top: .7em;
  font-size: .875rem;
  color: var(--c-stone);
}

@media (min-width: 780px) {
  .page-about .stat-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 团队分工 ---------- */
.page-about .team-split {
  display: grid;
  gap: clamp(20px, 3vw, 36px);
}

.page-about .role-list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .role {
  padding: 16px 18px;
  border-radius: var(--r-md);
  border-left: 3px solid var(--c-cyan);
  background: rgba(53, 224, 224, .07);
}

.page-about .role:nth-child(even) {
  border-left-color: var(--c-violet);
  background: rgba(123, 92, 255, .09);
}

.page-about .role h3 {
  margin: 0 0 .35em;
  font-family: var(--font-head);
  font-size: 1.0625rem;
  font-weight: 800;
  color: var(--c-paper);
}

.page-about .role p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.78;
  color: var(--c-mist);
}

@media (min-width: 920px) {
  .page-about .team-split {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    align-items: start;
  }
}

/* ---------- 合作生态 ---------- */
.page-about .partner-grid {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

@media (min-width: 920px) {
  .page-about .partner-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: end;
  }
}

/* ---------- 更新节奏 ---------- */
.page-about .cadence {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .cadence__item {
  display: grid;
  gap: 8px;
  padding: clamp(16px, 2.4vw, 24px) 0;
  border-top: 1px solid var(--c-hairline);
}

.page-about .cadence__item:last-child {
  border-bottom: 1px solid var(--c-hairline);
}

.page-about .cadence__key {
  font-family: var(--font-num);
  font-size: 1.125rem;
  font-weight: 900;
  letter-spacing: .06em;
  color: var(--c-cyan);
}

.page-about .cadence__item p {
  margin: 0;
  max-width: 42rem;
  line-height: 1.82;
}

.page-about .cadence__item:nth-child(even) .cadence__key {
  color: var(--c-violet);
}

@media (min-width: 780px) {
  .page-about .cadence__item {
    grid-template-columns: 120px minmax(0, 1fr);
    align-items: baseline;
    gap: 20px;
  }
}

/* ---------- 里程碑时间轴 ---------- */
.page-about .about-timeline__media {
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .milestone-list {
  --rail-w: 34px;
  position: relative;
  margin: 0;
  padding: 0 0 0 var(--rail-w);
  list-style: none;
}

.page-about .milestone-list::before {
  content: "";
  position: absolute;
  top: 10px;
  bottom: 10px;
  left: 6px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--c-cyan-ink), var(--c-violet));
  opacity: .45;
}

.page-about .milestone {
  position: relative;
  padding-bottom: clamp(14px, 2vw, 22px);
}

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

.page-about .milestone::before {
  content: "";
  position: absolute;
  top: 1.35em;
  left: calc(-1 * var(--rail-w) + 1px);
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--c-paper);
  border: 3px solid var(--c-cyan-ink);
}

.page-about .milestone:nth-child(even)::before {
  border-color: var(--c-violet);
}

.page-about .milestone__panel {
  border-radius: var(--r-md);
}

.page-about .milestone__sum {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 6px 10px 6px 0;
  list-style: none;
  cursor: pointer;
  border-radius: var(--r-sm);
}

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

.page-about .milestone__sum::marker {
  content: "";
}

.page-about .milestone__year {
  font-family: var(--font-num);
  font-size: clamp(1.35rem, 3.2vw, 1.9rem);
  font-weight: 900;
  line-height: 1;
  color: var(--c-cyan-ink);
}

.page-about .milestone:nth-child(even) .milestone__year {
  color: var(--c-violet-ink);
}

.page-about .milestone__title {
  font-family: var(--font-head);
  font-size: 1.0625rem;
  font-weight: 800;
  color: var(--c-ink);
}

.page-about .milestone__sum::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-num);
  font-size: 1.125rem;
  font-weight: 900;
  color: var(--c-stone);
}

.page-about .milestone__panel[open] .milestone__sum::after {
  content: "–";
}

.page-about .milestone__sum:focus-visible {
  outline: 2px solid var(--c-violet-ink);
  outline-offset: 2px;
}

.page-about .milestone__body {
  padding: 0 0 4px;
}

.page-about .milestone__body p {
  margin: .55em 0 0;
  max-width: 40rem;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--c-stone);
}

/* ---------- 我们坚持的事 ---------- */
.page-about .pledge-list {
  display: grid;
  gap: clamp(14px, 2vw, 20px);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .pledge {
  position: relative;
  padding: clamp(18px, 2.4vw, 26px);
  border-radius: var(--r-md);
  border: 1px solid var(--c-hairline);
  background: rgba(123, 92, 255, .07);
}

.page-about .pledge__no {
  display: block;
  margin-bottom: .5em;
  font-family: var(--font-num);
  font-size: 1.5rem;
  font-weight: 900;
  line-height: 1;
  color: var(--c-coral);
}

.page-about .pledge h3 {
  margin: 0 0 .5em;
  font-family: var(--font-head);
  font-size: 1.125rem;
  font-weight: 800;
  color: var(--c-paper);
}

.page-about .pledge p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--c-mist);
}

.page-about .pledge__foot {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 32px);
}

@media (min-width: 880px) {
  .page-about .pledge-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-link,
  .page-about .milestone__sum::after {
    transition: none;
  }
}