.page-about {
  padding-bottom: var(--s9);
  overflow-x: clip;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--s2);
  padding: var(--s5) 0 var(--s4);
  font-size: 13px;
  color: var(--gray);
}
.page-about .breadcrumbs__sep {
  color: var(--line);
}
.page-about .breadcrumbs__item[aria-current="page"] {
  color: var(--white);
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero__frame {
  margin-bottom: var(--s7);
}
.page-about .about-hero__grid {
  display: grid;
  gap: var(--s6);
}
.page-about .about-hero__copy {
  display: flex;
  flex-direction: column;
  gap: var(--s4);
}
.page-about .about-hero__copy h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(28px, 6vw, 56px);
  line-height: 1.12;
  letter-spacing: -0.01em;
  color: var(--white);
  margin: 0;
  max-width: 18ch;
}
.page-about .about-hero__lead {
  font-size: 16px;
  line-height: 1.75;
  color: var(--gray);
  margin: 0;
  max-width: 60ch;
}
.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s3);
  margin-top: var(--s2);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--s3);
  margin: 0;
}
.page-about .about-fact {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: rgba(26, 35, 32, 0.55);
  padding: var(--s4) var(--s4) var(--s3);
}
.page-about .about-fact__num {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: clamp(24px, 4.5vw, 34px);
  line-height: 1;
  color: var(--acid);
  letter-spacing: -0.02em;
}
.page-about .about-fact__label {
  display: block;
  margin: var(--s2) 0 0;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--gray);
}

/* ---------- 双栏外壳 ---------- */
.page-about .about-shell {
  display: grid;
  gap: var(--s6);
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--pad-x);
}
.page-about .about-rail .rail__list {
  display: flex;
  gap: var(--s2);
  overflow-x: auto;
  padding-bottom: var(--s2);
  margin: 0;
  list-style: none;
  scrollbar-width: thin;
}
.page-about .about-rail .rail__item {
  flex: 0 0 auto;
}
.page-about .about-body {
  min-width: 0;
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  scroll-margin-top: 96px;
}
.page-about .about-section + .about-section {
  margin-top: var(--s8);
}
.page-about .about-section h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(24px, 4.2vw, 40px);
  line-height: 1.2;
  color: var(--white);
  margin: var(--s2) 0 var(--s5);
  max-width: 22ch;
}
.page-about .about-section__lead {
  font-size: 16px;
  line-height: 1.75;
  color: var(--gray);
  max-width: 62ch;
  margin: 0 0 var(--s5);
}

/* ---------- 品牌支柱 ---------- */
.page-about .about-pillars {
  list-style: none;
  margin: var(--s6) 0 0;
  padding: 0;
  display: grid;
  gap: var(--s4);
}
.page-about .about-pillars__item {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: var(--panel-2);
  padding: var(--s5);
  transition: border-color 200ms ease;
}
.page-about .about-pillars__item:hover {
  border-color: var(--acid);
}
.page-about .about-pillars__item .label {
  display: inline-block;
  color: var(--acid);
  margin-bottom: var(--s3);
}
.page-about .about-pillars__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--gray);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: var(--s5);
}
.page-about .about-team__media img {
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .about-team__media {
  margin: 0;
}

.page-about .roles {
  list-style: none;
  margin: var(--s6) 0 0;
  padding: 0;
  display: grid;
  gap: var(--s4);
}
.page-about .roles__item {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: var(--data);
  padding: var(--s4) var(--s5);
  transition: border-color 200ms ease;
}
.page-about .roles__item:hover {
  border-color: var(--fit);
}
.page-about .roles__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--s3);
  margin-bottom: var(--s3);
}
.page-about .roles__name {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 17px;
  color: var(--white);
}
.page-about .roles__num {
  font-size: 22px;
  color: var(--acid);
}
.page-about .roles__desc {
  margin: var(--s3) 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--gray);
}
.page-about .bar {
  display: block;
  height: 8px;
  border-radius: var(--r-pill);
  background: rgba(28, 68, 56, 0.6);
  overflow: hidden;
}
.page-about .bar__fill {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: var(--grad-acid);
}

/* ---------- 工作流 ---------- */
.page-about .about-workflow__media {
  margin: 0 0 var(--s6);
}
.page-about .about-workflow__media img {
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--s4);
  counter-reset: flow;
}
.page-about .flow__item {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: linear-gradient(135deg, rgba(15, 42, 35, 0.9), rgba(18, 46, 39, 0.75));
  padding: var(--s5);
  overflow: hidden;
}
.page-about .flow__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 40px;
  line-height: 1;
  font-weight: 500;
  color: rgba(201, 255, 61, 0.28);
  margin-bottom: var(--s3);
}
.page-about .flow__title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 19px;
  color: var(--white);
  margin: 0 0 var(--s3);
}
.page-about .flow__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--gray);
}

/* ---------- 更新节奏 ---------- */
.page-about .about-rhythm {
  margin-bottom: var(--s6);
}
.page-about .about-rhythm__block {
  border-left: 2px solid var(--line);
  padding-left: var(--s5);
}
.page-about .about-rhythm__block:nth-child(2) {
  border-left-color: var(--fit);
}
.page-about .about-rhythm__block h3 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 20px;
  color: var(--white);
  margin: 0 0 var(--s3);
}
.page-about .about-rhythm__block p {
  margin: 0 0 var(--s3);
  font-size: 15px;
  line-height: 1.75;
  color: var(--gray);
}
.page-about .about-rhythm__block p:last-child {
  margin-bottom: 0;
}

.page-about .about-rhythm__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--s4);
  border-top: 1px dashed var(--line);
  padding-top: var(--s6);
}
.page-about .stat__value {
  display: block;
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: clamp(28px, 5vw, 44px);
  line-height: 1;
  color: var(--acid);
  letter-spacing: -0.02em;
}
.page-about .stat__unit {
  font-size: 0.42em;
  color: var(--gray);
  margin-left: 4px;
  letter-spacing: 0.04em;
}
.page-about .stat__label {
  display: block;
  margin-top: var(--s2);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--gray);
}

/* ---------- 发展历程时间线 ---------- */
.page-about .hist {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--s5);
}
.page-about .hist::before {
  content: "";
  position: absolute;
  left: 21px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--acid), var(--fit) 50%, var(--line));
}
.page-about .hist__item {
  position: relative;
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: var(--s4);
}
.page-about .hist__node {
  display: flex;
  justify-content: center;
  padding-top: 24px;
}
.page-about .hist__dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--acid);
  box-shadow: 0 0 0 4px rgba(201, 255, 61, 0.12);
}
.page-about .hist__card {
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--panel);
  padding: var(--s5);
  transition: border-color 240ms ease, transform 240ms ease;
}
.page-about .hist__card:hover {
  border-color: var(--fit);
}
.page-about .hist__year {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 26px;
  line-height: 1;
  color: var(--acid);
  margin: 0 0 var(--s3);
  letter-spacing: -0.02em;
}
.page-about .hist__title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 19px;
  color: var(--white);
  margin: 0 0 var(--s3);
}
.page-about .hist__card > p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--gray);
}

/* ---------- 展开细节 ---------- */
.page-about .more {
  margin-top: var(--s4);
  border-top: 1px dashed var(--line);
  padding-top: var(--s3);
}
.page-about .more > summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: var(--s2);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--acid);
  transition: color 160ms ease;
}
.page-about .more > summary::-webkit-details-marker {
  display: none;
}
.page-about .more > summary::before {
  content: "+";
  font-size: 14px;
  line-height: 1;
}
.page-about .more[open] > summary::before {
  content: "–";
}
.page-about .more > summary:hover {
  color: var(--fit);
}
.page-about .more p {
  margin: var(--s3) 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--gray);
}

/* ---------- 合作与社群 ---------- */
.page-about .about-partners {
  display: grid;
  gap: var(--s5);
}
.page-about .about-partners__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s3);
  margin-top: var(--s5);
}
.page-about .about-partners__media {
  margin: 0;
}
.page-about .about-partners__media img {
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-pillars {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-rhythm__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-partners {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .about-team {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: start;
  }
}

@media (min-width: 1100px) {
  .page-about .flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    gap: var(--s7);
    align-items: start;
  }
}

@media (min-width: 1180px) {
  .page-about .about-shell {
    grid-template-columns: 260px minmax(0, 1fr);
    gap: var(--s7);
    align-items: start;
  }
  .page-about .about-rail {
    position: sticky;
    top: 96px;
  }
  .page-about .about-rail .rail__list {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
    gap: var(--s1);
  }
  .page-about .about-rail .rail__item {
    flex: 0 0 auto;
  }

  /* 时间线左右交替 */
  .page-about .hist::before {
    left: calc(50% - 1px);
  }
  .page-about .hist__item {
    grid-template-columns: minmax(0, 1fr) 44px minmax(0, 1fr);
  }
  .page-about .hist__node {
    grid-column: 2;
  }
  .page-about .hist__item:nth-child(odd) .hist__card {
    grid-column: 1;
  }
  .page-about .hist__item:nth-child(even) .hist__card {
    grid-column: 3;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .hist__card,
  .page-about .roles__item,
  .page-about .about-pillars__item {
    transition: none;
  }
}