.page-about {
  --about-gap: clamp(1.25rem, 3.5vw, 2.5rem);
  --about-pad: clamp(2.5rem, 7vw, 5rem);
  --about-node: 0.5625rem;
  background: var(--pitch-900);
  color: var(--fg);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding-top: clamp(1rem, 3vw, 1.75rem);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-block: clamp(1.5rem, 4vw, 2.75rem) var(--about-pad);
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--orange) 0%, var(--volt) 44%, rgba(180, 255, 58, 0) 100%);
}
.page-about .about-hero__grid {
  display: grid;
  gap: var(--about-gap);
  margin-top: clamp(1.25rem, 3.5vw, 2.25rem);
}
.page-about .about-hero__title {
  margin: 0;
}
.page-about .about-hero__title .thin-word {
  font-weight: 200;
  color: var(--mist);
}
.page-about .about-hero__aside {
  max-width: 62ch;
}
.page-about .about-hero__aside .prose {
  margin: 0 0 0.875rem;
  color: var(--fg);
}
.page-about .about-hero__aside .prose + .prose {
  color: var(--muted);
}
.page-about .about-hero__actions {
  list-style: none;
  margin: clamp(1.25rem, 3vw, 1.75rem) 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* ---------- 通用标题 ---------- */
.page-about .about-h2 {
  margin: 0.75rem 0 0;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: clamp(1.375rem, 3.2vw, 2rem);
  line-height: 1.26;
  letter-spacing: -0.01em;
  max-width: 32ch;
}

/* ---------- 里程碑数字带 ---------- */
.page-about .about-milestones {
  padding-block: var(--about-pad);
}
.page-about .about-milestones__grid {
  display: grid;
  gap: var(--about-gap);
}
.page-about .about-milestones__text {
  margin: 0.875rem 0 0;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--muted);
  max-width: 42ch;
}
.page-about .about-milestones__stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}
.page-about .about-milestones__stats li {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
  padding: clamp(0.875rem, 2.4vw, 1.25rem);
  background: var(--pitch-900);
}
.page-about .about-milestones__stats .stat-figure {
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 4.4vw, 2.125rem);
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--volt);
}
.page-about .about-milestones__stats .stat-unit {
  margin-left: 0.25rem;
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  color: var(--mist);
}
.page-about .about-milestones__cap {
  font-size: 0.8125rem;
  line-height: 1.55;
  color: var(--muted);
}
.page-about .about-milestones__figure {
  margin: 0;
}

/* ---------- 段落面板通用 ---------- */
.page-about .about-section {
  position: relative;
  padding-block: var(--about-pad);
  border-top: 1px solid var(--line);
}
.page-about .about-section--dark {
  background: var(--pitch-900);
}
.page-about .about-section--paper {
  background: var(--paper);
  color: var(--ink);
}
.page-about .about-section--paper .index-label {
  color: var(--burgundy-700);
}
.page-about .about-section--paper .about-h2 {
  color: var(--ink);
}
.page-about .about-section--paper .prose {
  color: rgba(10, 20, 18, 0.82);
}

/* ---------- 图框 ---------- */
.page-about .media-frame {
  margin: 0;
  background: var(--teal-800);
  border: 1px solid var(--line);
}
.page-about .media-frame img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.9);
  transition: filter 260ms ease;
}
.page-about .media-frame:hover img {
  filter: saturate(1.05);
}
.page-about .media-caption {
  padding: 0.625rem 0.875rem;
  border-top: 1px solid var(--line);
  font-size: 0.75rem;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 起点 ---------- */
.page-about .about-origin {
  display: grid;
  gap: var(--about-gap);
}
.page-about .about-origin__text .prose {
  max-width: 64ch;
}
.page-about .about-origin__text .prose:first-of-type {
  margin-top: clamp(1rem, 2.6vw, 1.5rem);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline__lede {
  margin: 0.75rem 0 0;
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--muted);
  max-width: 56ch;
}
.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: clamp(1.75rem, 4vw, 2.5rem) 0 0;
  padding: 0 0 0 1.5rem;
  display: grid;
  gap: clamp(0.875rem, 2.4vw, 1.25rem);
}
.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.75rem;
  bottom: 0.75rem;
  width: 1px;
  background: var(--line-strong);
}
.page-about .about-timeline__item {
  position: relative;
  padding: clamp(1rem, 2.6vw, 1.5rem);
  border: 1px solid var(--line);
  background: rgba(14, 58, 63, 0.3);
  transition: background-color 220ms ease, border-color 220ms ease;
}
.page-about .about-timeline__item:hover,
.page-about .about-timeline__item:focus-within {
  background: rgba(36, 30, 78, 0.48);
  border-color: var(--line-strong);
}
.page-about .about-timeline__node {
  position: absolute;
  left: calc(-1.5rem - 0.28125rem);
  top: clamp(1.375rem, 3vw, 1.875rem);
  width: var(--about-node);
  height: var(--about-node);
  background: var(--brass);
  transition: background-color 220ms ease, box-shadow 220ms ease;
}
.page-about .about-timeline__item:hover .about-timeline__node,
.page-about .about-timeline__item:focus-within .about-timeline__node {
  background: var(--volt);
  box-shadow: 0 0 0 4px rgba(180, 255, 58, 0.16);
}
.page-about .about-timeline__node--now {
  background: var(--volt);
  box-shadow: 0 0 0 4px rgba(180, 255, 58, 0.14);
}
.page-about .about-timeline__phase {
  margin: 0;
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  color: var(--orange);
}
.page-about .about-timeline__title {
  margin: 0.5rem 0 0;
  font-size: clamp(1rem, 2vw, 1.125rem);
  font-weight: 700;
  line-height: 1.35;
  letter-spacing: -0.005em;
}
.page-about .about-timeline__body {
  margin: 0.5rem 0 0;
  font-size: 0.9375rem;
  line-height: 1.72;
  color: var(--muted);
  max-width: 66ch;
}

/* ---------- 横向主题带 ---------- */
.page-about .about-pause {
  padding-block: clamp(2rem, 5.5vw, 3.5rem);
}
.page-about .about-pause__inner {
  display: grid;
  gap: 1rem;
  align-items: start;
}
.page-about .about-pause__line {
  margin: 0;
  font-size: clamp(1.0625rem, 2.4vw, 1.375rem);
  font-weight: 500;
  line-height: 1.62;
  letter-spacing: -0.005em;
  max-width: 46ch;
}

/* ---------- 团队 ---------- */
.page-about .about-team__lead {
  display: grid;
  gap: var(--about-gap);
  margin-top: clamp(1.25rem, 3.5vw, 2rem);
}
.page-about .about-team__lead .prose {
  max-width: 60ch;
  color: var(--muted);
}
.page-about .about-team__grid {
  list-style: none;
  margin: clamp(1.75rem, 4vw, 2.5rem) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}
.page-about .about-team__cell {
  padding: clamp(1.125rem, 3vw, 1.75rem);
  background: var(--teal-800);
}
.page-about .about-team__idx {
  margin: 0;
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  color: var(--brass);
}
.page-about .about-team__cell h3 {
  margin: 0.5rem 0 0;
  font-size: 1.0625rem;
  font-weight: 700;
  line-height: 1.35;
  color: var(--fg);
}
.page-about .about-team__cell > p {
  margin: 0.625rem 0 0;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--muted);
}
.page-about .about-team__duties {
  list-style: none;
  margin: 0.875rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.5rem;
}
.page-about .about-team__duties li {
  position: relative;
  padding-left: 0.9375rem;
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--fg);
}
.page-about .about-team__duties li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.6875rem;
  width: 0.375rem;
  height: 1px;
  background: var(--brass);
}

/* ---------- 数据方法 ---------- */
.page-about .about-method {
  list-style: none;
  margin: clamp(1.5rem, 3.5vw, 2.25rem) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}
.page-about .about-method__step {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding: clamp(1.125rem, 3vw, 1.75rem);
  background: var(--indigo-700);
  transition: background-color 220ms ease;
}
.page-about .about-method__step:hover {
  background: #2c2560;
}
.page-about .about-method__num {
  margin: 0;
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  color: var(--volt);
}
.page-about .about-method__step h3 {
  margin: 0;
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--fg);
}
.page-about .about-method__step p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.72;
  color: var(--muted);
}
.page-about .about-method__note {
  margin: clamp(1.25rem, 3vw, 1.75rem) 0 0;
  padding-left: 0.875rem;
  border-left: 2px solid var(--orange);
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--fg);
  max-width: 62ch;
}

/* ---------- 合作与实践 ---------- */
.page-about .about-partners {
  display: grid;
  gap: var(--about-gap);
}
.page-about .about-partners__text .prose {
  margin-top: clamp(1rem, 2.6vw, 1.5rem);
  max-width: 60ch;
  color: var(--muted);
}
.page-about .about-partners__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}
.page-about .about-partners__list li {
  padding: 0.875rem 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--fg);
}
.page-about .about-partners__num {
  display: inline-block;
  margin: 0 0.25rem;
  font-size: 1.0625rem;
  color: var(--volt);
}

/* ---------- 长期坚持 ---------- */
.page-about .about-keep__list {
  list-style: none;
  margin: clamp(1.25rem, 3vw, 1.75rem) 0 0;
  padding: 0;
  max-width: 70ch;
}
.page-about .about-keep__list li {
  padding: 0.875rem 0;
  border-top: 1px solid rgba(10, 20, 18, 0.16);
  font-size: 0.9375rem;
  line-height: 1.72;
  color: rgba(10, 20, 18, 0.86);
}
.page-about .about-keep__list li:last-child {
  border-bottom: 1px solid rgba(10, 20, 18, 0.16);
}
.page-about .about-keep__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: clamp(1.5rem, 3.5vw, 2rem);
}
.page-about .about-section--paper .btn--ghost {
  color: var(--ink);
  border-color: rgba(10, 20, 18, 0.34);
  background: transparent;
}
.page-about .about-section--paper .btn--ghost:hover,
.page-about .about-section--paper .btn--ghost:focus-visible {
  color: var(--paper);
  background: var(--burgundy-700);
  border-color: var(--burgundy-700);
}

/* ---------- 响应式 ---------- */
@media (min-width: 40rem) {
  .page-about .about-milestones__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 52rem) {
  .page-about .about-team__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-team__lead {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
    align-items: center;
    column-gap: clamp(2rem, 5vw, 4rem);
  }
  .page-about .about-team__lead .prose {
    margin-top: 0;
  }
  .page-about .about-method {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 60rem) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    align-items: end;
    column-gap: clamp(2rem, 5vw, 4rem);
  }
  .page-about .about-milestones__grid {
    grid-template-columns: minmax(0, 4fr) minmax(0, 5fr) minmax(0, 3fr);
    align-items: start;
    column-gap: clamp(1.5rem, 4vw, 2.75rem);
  }
  .page-about .about-origin {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
    align-items: center;
    column-gap: clamp(2rem, 5vw, 4rem);
  }
  .page-about .about-origin__text .prose:first-of-type {
    margin-top: clamp(1.25rem, 3vw, 1.75rem);
  }
  .page-about .about-pause__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: end;
    column-gap: clamp(2rem, 6vw, 4rem);
  }
  .page-about .about-pause__inner .index-label {
    grid-column: 1 / -1;
  }
  .page-about .about-partners {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
    column-gap: clamp(2rem, 5vw, 4rem);
  }
}

@media (min-width: 68rem) {
  .page-about .about-timeline__item {
    display: grid;
    grid-template-columns: 13rem minmax(0, 1fr);
    column-gap: clamp(1.25rem, 3vw, 2.5rem);
    align-items: start;
  }
  .page-about .about-timeline__phase {
    grid-column: 1;
    padding-top: 0.25rem;
  }
  .page-about .about-timeline__title {
    grid-column: 2;
    margin-top: 0;
  }
  .page-about .about-timeline__body {
    grid-column: 2;
  }
  .page-about .about-method {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__item,
  .page-about .about-timeline__node,
  .page-about .about-method__step,
  .page-about .media-frame img {
    transition: none;
  }
}