.page-about {
  --about-sticky: 128px;
  background: var(--paper);
  color: var(--charcoal);
  font-family: var(--font-sans);
  padding-bottom: 72px;
  overflow-x: hidden;
}

.page-about .container {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
  box-sizing: border-box;
}

/* 面包屑 */
.page-about .breadcrumb {
  padding: 18px 0 4px;
}
.page-about .breadcrumb-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
  font-size: 13px;
}
.page-about .breadcrumb-item {
  color: var(--muted);
}
.page-about .breadcrumb-item + .breadcrumb-item::before {
  content: "／";
  margin-right: 6px;
  color: var(--rule);
}
.page-about .breadcrumb-item a {
  color: var(--grass-deep);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}
.page-about .breadcrumb-item a:hover,
.page-about .breadcrumb-item a:focus-visible {
  border-bottom-color: currentColor;
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
  padding: 10px 0 42px;
}
.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -30px -8% 32% -8%;
  background:
    radial-gradient(58% 68% at 16% 22%, rgba(47, 158, 79, 0.16), transparent 70%),
    radial-gradient(48% 58% at 84% 8%, rgba(242, 107, 33, 0.12), transparent 72%),
    radial-gradient(44% 52% at 62% 86%, rgba(20, 200, 160, 0.1), transparent 70%);
  pointer-events: none;
  z-index: 0;
}
.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 28px;
}
.page-about .exhibit-label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--grass-deep);
}
.page-about h1 {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(30px, 6.2vw, 54px);
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin: 12px 0 18px;
}
.page-about .lede {
  margin: 0;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .hero-marks {
  list-style: none;
  margin: 26px 0 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--rule);
  display: grid;
  gap: 14px;
}
.page-about .hero-marks__num {
  display: block;
  font-size: 24px;
  font-weight: 500;
  line-height: 1.1;
  color: var(--ink);
}
.page-about .hero-marks li:nth-child(2) .hero-marks__num {
  color: var(--grass-deep);
}
.page-about .hero-marks li:nth-child(3) .hero-marks__num {
  color: var(--track);
}
.page-about .hero-marks__txt {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  color: var(--muted);
}

/* 图片与图注 */
.page-about .figure {
  margin: 0;
}
.page-about .figure__media {
  background: var(--mist);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.page-about .figure__media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .figure__cap {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--muted);
}

/* 正文骨架 */
.page-about .about-body {
  display: block;
  padding-top: 20px;
}
.page-about .about-flow {
  min-width: 0;
}

/* 左侧刻度 */
.page-about .year-rail {
  display: none;
}
.page-about .year-rail__title {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--muted);
}
.page-about .year-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 24px;
}
.page-about .year-rail__list::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--rule);
}
.page-about .year-tick {
  display: flex;
  align-items: center;
  gap: 7px;
  text-decoration: none;
  font-size: 12px;
  color: var(--muted);
}
.page-about .year-tick__dot {
  flex: none;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  border: 1.5px solid var(--rule);
  background: var(--paper);
  position: relative;
  z-index: 1;
  transition: background 0.14s linear, border-color 0.14s linear;
}
.page-about .year-tick__num {
  font-size: 12px;
  color: var(--ink);
}
.page-about .year-tick__lb {
  font-weight: 500;
}
.page-about .year-tick:hover .year-tick__dot,
.page-about .year-tick:focus-visible .year-tick__dot {
  background: var(--grass);
  border-color: var(--grass);
}
.page-about .year-tick:hover .year-tick__lb,
.page-about .year-tick:focus-visible .year-tick__lb {
  color: var(--grass-deep);
}

/* 章节 */
.page-about .flow-section {
  padding: 34px 0 12px;
  scroll-margin-top: 96px;
}
.page-about .flow-head {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-top: 16px;
  margin-bottom: 16px;
}
.page-about .flow-head::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 64px;
  height: 8px;
  background: var(--grass);
}
.page-about .flow-section:nth-of-type(even) .flow-head::before {
  background: var(--track);
}
.page-about .flow-head__num {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ink);
}
.page-about .flow-head__word {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--ink);
}
.page-about h2 {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(23px, 4.4vw, 34px);
  line-height: 1.26;
  letter-spacing: -0.005em;
  color: var(--ink);
  margin: 0 0 16px;
}
.page-about .flow-section h2::after {
  content: "";
  display: block;
  width: 44px;
  height: 3px;
  margin-top: 12px;
  background: var(--grass);
}
.page-about .flow-section:nth-of-type(even) h2::after {
  background: var(--track);
}
.page-about .about-flow p {
  margin: 0 0 14px;
  max-width: 40em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--charcoal);
}

/* 版本台阶 */
.page-about .ver-figure {
  margin: 22px 0 24px;
}
.page-about .ver-wrap {
  position: relative;
}
.page-about .ver-arc {
  display: none;
}
.page-about .ver-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
  position: relative;
  z-index: 1;
}
.page-about .ver-node details {
  background: var(--paper);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.page-about .ver-node details[open] {
  border-color: var(--grass);
}
.page-about .ver-node summary {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 14px;
  cursor: pointer;
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}
.page-about .ver-node summary::-webkit-details-marker {
  display: none;
}
.page-about .ver-node summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--grass-deep);
}
.page-about .ver-node details[open] summary::after {
  content: "－";
}
.page-about .ver-node summary:focus-visible {
  outline: 2px solid var(--track);
  outline-offset: 2px;
}
.page-about .ver-tag {
  flex: none;
  font-size: 11px;
  letter-spacing: 0.06em;
  padding: 3px 7px;
  border-radius: 4px;
  background: var(--mist);
  color: var(--grass-deep);
}
.page-about .ver-name {
  min-width: 0;
}
.page-about .ver-node p {
  margin: 0;
  padding: 0 14px 14px;
  max-width: none;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* 团队 */
.page-about .cols {
  display: grid;
  gap: 24px;
}
.page-about .cols__main,
.page-about .cols__aside {
  min-width: 0;
}
.page-about .day-list {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  border-left: 2px solid var(--mist);
}
.page-about .day-list li {
  position: relative;
  padding: 0 0 16px 18px;
}
.page-about .day-list li:last-child {
  padding-bottom: 4px;
}
.page-about .day-list li::before {
  content: "";
  position: absolute;
  left: -6px;
  top: 5px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px var(--paper);
}
.page-about .day-list li:nth-child(2)::before {
  background: var(--grass);
}
.page-about .day-list li:nth-child(3)::before {
  background: var(--track);
}
.page-about .day-list__t {
  display: block;
  margin-bottom: 3px;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ink);
}
.page-about .day-list p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .status-legend {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 16px 0 0;
  padding: 0;
}
.page-about .tag {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 5px 12px;
  border-radius: 999px;
  border: 1px solid var(--rule);
  background: var(--paper);
  color: var(--ink);
  font-size: 13px;
  font-weight: 600;
}
.page-about .tag--ok {
  color: var(--grass-deep);
  border-color: rgba(20, 200, 160, 0.55);
  background: rgba(20, 200, 160, 0.1);
}
.page-about .tag--ok::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--cyan);
}
.page-about .tag--warn {
  color: #a6470f;
  border-color: var(--track);
  background: var(--peach);
}

/* 共建徽章 */
.page-about .eco-badges {
  list-style: none;
  margin: 26px 0 22px;
  padding: 0;
  display: grid;
  gap: 24px;
  justify-items: center;
}
.page-about .eco-badge {
  max-width: 260px;
  text-align: center;
}
.page-about .eco-badge__ring {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 132px;
  height: 132px;
  margin: 0 auto 12px;
  border-radius: 50%;
  border: 2px solid var(--grass);
  background:
    radial-gradient(circle at 30% 24%, rgba(47, 158, 79, 0.15), transparent 66%),
    var(--paper);
  transition: transform 0.22s var(--ease);
}
.page-about .eco-badge:nth-child(2) .eco-badge__ring {
  border-color: var(--track);
  background:
    radial-gradient(circle at 30% 24%, rgba(242, 107, 33, 0.14), transparent 66%),
    var(--paper);
}
.page-about .eco-badge:nth-child(3) .eco-badge__ring {
  border-color: var(--ink-2);
  background:
    radial-gradient(circle at 30% 24%, rgba(16, 36, 61, 0.12), transparent 66%),
    var(--paper);
}
.page-about .eco-badge:hover .eco-badge__ring {
  transform: scale(1.04);
}
.page-about .eco-badge__num {
  font-size: 30px;
  font-weight: 500;
  line-height: 1;
  color: var(--ink);
}
.page-about .eco-badge__lb {
  margin-top: 6px;
  padding: 0 12px;
  font-size: 12px;
  line-height: 1.4;
  color: var(--muted);
}
.page-about .eco-badge__note {
  margin: 0;
  max-width: none;
  font-size: 13px;
  line-height: 1.65;
  color: var(--muted);
}

/* 引文块 */
.page-about .pull {
  position: relative;
  margin: 24px 0;
  padding: 26px 20px 22px;
  border: 2px solid var(--ink);
  border-radius: var(--radius);
  background: var(--mist);
}
.page-about .pull::before {
  content: "";
  position: absolute;
  inset: 6px;
  border: 1px dashed var(--rule);
  border-radius: 4px;
  pointer-events: none;
}
.page-about .pull p {
  position: relative;
  margin: 12px 0 10px;
  max-width: 30em;
  font-family: var(--font-serif);
  font-size: clamp(17px, 2.6vw, 21px);
  line-height: 1.62;
  color: var(--ink);
}
.page-about .pull cite {
  position: relative;
  font-style: normal;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}
.page-about .outlook-points {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}
.page-about .outlook-points li {
  position: relative;
  padding-left: 26px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--charcoal);
}
.page-about .outlook-points li::before {
  content: "→";
  position: absolute;
  left: 0;
  top: 0;
  font-family: var(--font-mono);
  color: var(--grass);
}

/* 结尾入口 */
.page-about .about-cta {
  padding-bottom: 0;
}
.page-about .cta-grid {
  display: grid;
  gap: 14px;
  margin-top: 22px;
}
.page-about .cta-card {
  display: block;
  padding: 18px 16px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: var(--shadow);
  text-decoration: none;
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease);
}
.page-about .cta-card:hover,
.page-about .cta-card:focus-visible {
  border-color: var(--grass);
  transform: translateY(-2px);
}
.page-about .cta-card__k {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--track);
}
.page-about .cta-card__t {
  display: block;
  margin-bottom: 6px;
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}
.page-about .cta-card__d {
  display: block;
  font-size: 13px;
  line-height: 1.65;
  color: var(--muted);
}
.page-about .cta-note {
  margin: 18px 0 0;
  max-width: none;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  color: var(--muted);
}

/* 响应式 */
@media (min-width: 560px) {
  .page-about .hero-marks {
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
  }
  .page-about .eco-badges {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 760px) {
  .page-about .ver-wrap {
    padding-top: 6px;
  }
  .page-about .ver-arc {
    display: block;
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    opacity: 0.22;
    pointer-events: none;
  }
  .page-about .ver-list {
    gap: 10px;
  }
  .page-about .ver-list > li:nth-child(1) { margin-left: 0; }
  .page-about .ver-list > li:nth-child(2) { margin-left: 44px; }
  .page-about .ver-list > li:nth-child(3) { margin-left: 88px; }
  .page-about .ver-list > li:nth-child(4) { margin-left: 132px; }
  .page-about .ver-list > li:nth-child(5) { margin-left: 176px; }
  .page-about .eco-badges {
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
  }
  .page-about .cta-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .page-about .pull {
    padding: 32px 28px 26px;
  }
}

@media (min-width: 820px) {
  .page-about .cols--split {
    grid-template-columns: 1fr 0.82fr;
    align-items: start;
    gap: 36px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 16px 0 56px;
  }
  .page-about .about-hero__grid {
    grid-template-columns: 1.06fr 0.94fr;
    gap: 48px;
    align-items: start;
  }
  .page-about .lede {
    font-size: 17px;
  }
  .page-about .flow-section {
    padding: 44px 0 14px;
  }
}

@media (min-width: 960px) {
  .page-about .about-body {
    display: grid;
    grid-template-columns: 84px minmax(0, 1fr);
    gap: 52px;
    align-items: start;
    padding-top: 26px;
  }
  .page-about .year-rail {
    display: block;
    position: sticky;
    top: var(--about-sticky);
    align-self: start;
    padding-top: 44px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .eco-badge__ring,
  .page-about .cta-card,
  .page-about .year-tick__dot {
    transition: none;
  }
  .page-about .eco-badge:hover .eco-badge__ring {
    transform: none;
  }
  .page-about .cta-card:hover,
  .page-about .cta-card:focus-visible {
    transform: none;
  }
}