.page-about {
  --about-rail-w: 200px;
  --about-gap: clamp(28px, 4vw, 72px);
  padding-bottom: clamp(48px, 7vw, 96px);
}

/* ---------- 封面首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: calc(var(--header-h) + clamp(44px, 8vw, 104px)) 0 clamp(48px, 7vw, 92px);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(120% 90% at 84% 0%, rgba(25, 195, 125, .17), transparent 58%),
    radial-gradient(90% 80% at 4% 100%, rgba(46, 155, 255, .14), transparent 62%),
    var(--bg);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(90deg, rgba(201, 255, 61, .05) 0 1px, transparent 1px 76px),
    repeating-linear-gradient(0deg, rgba(36, 52, 58, .45) 0 1px, transparent 1px 76px);
  opacity: .55;
}

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

.page-about .about-crumbs {
  margin-bottom: 22px;
}

.page-about .about-crumbs a {
  color: var(--muted);
  text-decoration: none;
  transition: color .18s ease;
}

.page-about .about-crumbs a:hover,
.page-about .about-crumbs a:focus-visible {
  color: var(--green);
}

.page-about .about-hero-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 6.1vw, 66px);
  line-height: 1.08;
  letter-spacing: -.022em;
  margin: 16px 0 0;
  max-width: 17em;
}

.page-about .about-hero-lede {
  margin-top: clamp(18px, 2.4vw, 28px);
  max-width: 44em;
  color: var(--ink-soft);
}

.page-about .about-hero-stats {
  list-style: none;
  margin: clamp(30px, 4vw, 48px) 0 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 .hero-stat {
  background: var(--panel);
  padding: 18px 18px 16px;
  min-width: 0;
}

.page-about .hero-stat-num {
  display: block;
  font-size: clamp(22px, 2.8vw, 32px);
  font-weight: 700;
  letter-spacing: -.02em;
  color: var(--ink);
  line-height: 1.1;
}

.page-about .hero-stat:first-child .hero-stat-num {
  color: var(--lime);
}

.page-about .hero-stat-label {
  display: block;
  margin-top: 8px;
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--muted);
}

.page-about .about-hero-actions {
  margin-top: clamp(24px, 3vw, 36px);
}

/* ---------- 骨架网格 ---------- */
.page-about .about-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 56px);
  padding-top: clamp(36px, 5vw, 72px);
}

/* ---------- 左侧章节索引 ---------- */
.page-about .about-rail {
  border: 1px solid var(--line);
  background: var(--panel);
  padding: 16px;
  border-radius: 2px;
}

.page-about .about-rail-title {
  margin: 0;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--muted);
  text-transform: uppercase;
}

.page-about .about-rail-list {
  list-style: none;
  margin: 12px 0 0;
  padding: 0 0 4px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail-list li {
  flex: 0 0 auto;
}

.page-about .about-rail-link {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 9px 13px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--bg);
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color .18s ease, color .18s ease, background-color .18s ease;
}

.page-about .about-rail-link:hover,
.page-about .about-rail-link:focus-visible {
  border-color: var(--green);
  color: var(--ink);
  background: var(--raise);
}

.page-about .rail-num {
  font-size: 11.5px;
  letter-spacing: .05em;
  color: var(--green);
}

.page-about .about-rail-scale {
  display: none;
}

/* ---------- 章节通用 ---------- */
.page-about .about-body > .about-section {
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .about-section {
  padding: clamp(34px, 4.6vw, 58px) 0;
  border-top: 1px solid var(--line);
}

.page-about .about-section:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-num {
  display: inline-block;
  font-size: clamp(26px, 3.6vw, 42px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--green);
  padding-bottom: 10px;
  border-bottom: 2px solid var(--green);
  margin-bottom: 16px;
}

.page-about .about-body > .about-section:nth-child(even) .about-num {
  color: var(--blue);
  border-bottom-color: var(--blue);
}

.page-about .about-section-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(21px, 3.3vw, 36px);
  line-height: 1.2;
  letter-spacing: -.014em;
  margin: 0 0 16px;
  max-width: 20em;
}

.page-about .about-section-lead {
  margin: 0 0 22px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--ink-soft);
  max-width: 44em;
}

.page-about .about-copy p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--ink-soft);
  max-width: 44em;
}

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

.page-about .about-inline-link {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(46, 155, 255, .45);
  transition: color .18s ease, border-color .18s ease;
}

.page-about .about-inline-link:hover,
.page-about .about-inline-link:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

/* ---------- 配图 ---------- */
.page-about .about-figure {
  margin: 0;
  min-width: 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: 2px;
  object-fit: cover;
  background: var(--panel);
}

.page-about .about-figure figcaption {
  margin-top: 12px;
  padding-left: 12px;
  border-left: 2px solid var(--green);
  font-size: 13px;
  line-height: 1.68;
  color: var(--muted);
}

/* ---------- 团队 ---------- */
.page-about .team-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 44px);
  align-items: start;
}

.page-about .role-bars {
  display: grid;
  gap: 22px;
  min-width: 0;
}

.page-about .role-bar-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 9px;
}

.page-about .role-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .role-count {
  font-size: 14px;
  font-weight: 700;
  color: var(--lime);
  flex: 0 0 auto;
}

.page-about .role-bar-track {
  height: 7px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 999px;
  overflow: hidden;
}

.page-about .role-bar-fill {
  display: block;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--green), var(--blue));
}

.page-about .role-bar--a .role-bar-fill { width: 34.8%; }
.page-about .role-bar--b .role-bar-fill { width: 23.9%; background: linear-gradient(90deg, var(--blue), var(--green)); }
.page-about .role-bar--c .role-bar-fill { width: 26.1%; background: linear-gradient(90deg, var(--green), var(--lime)); }
.page-about .role-bar--d .role-bar-fill { width: 15.2%; background: linear-gradient(90deg, var(--blue), var(--lime)); }

.page-about .role-bar-note {
  margin: 9px 0 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--muted);
  max-width: 40em;
}

/* ---------- 三道环节 ---------- */
.page-about .flow-steps {
  list-style: none;
  margin: 4px 0 0;
  padding: 0;
}

.page-about .flow-step {
  position: relative;
  padding: 20px 0 20px 58px;
  border-bottom: 1px solid var(--line);
}

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

.page-about .flow-step-num {
  position: absolute;
  left: 0;
  top: 20px;
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  font-size: 14px;
  font-weight: 700;
  color: var(--lime);
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 2px;
}

.page-about .flow-step h3 {
  margin: 0 0 7px;
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .flow-step p {
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
  color: var(--muted);
  max-width: 42em;
}

.page-about .flow-note {
  margin: 22px 0 0;
  padding: 14px 18px;
  border-left: 3px solid var(--alert);
  background: var(--panel);
  font-size: 15px;
  line-height: 1.72;
  color: var(--ink-soft);
  max-width: 42em;
}

.page-about .about-figure--wide {
  margin-top: clamp(26px, 3.6vw, 42px);
  max-width: 720px;
}

/* ---------- 合作生态 ---------- */
.page-about .eco-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin-top: 24px;
}

.page-about .eco-card {
  background: var(--panel);
  padding: clamp(18px, 2.4vw, 28px);
  min-width: 0;
}

.page-about .eco-card-num {
  display: block;
  font-size: clamp(24px, 2.6vw, 32px);
  font-weight: 700;
  letter-spacing: -.02em;
  color: var(--blue);
  margin-bottom: 12px;
  line-height: 1;
}

.page-about .eco-card h3 {
  margin: 0 0 9px;
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .eco-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.74;
  color: var(--muted);
}

/* ---------- 版本 ---------- */
.page-about .version-chips {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .version-chip {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--panel);
  color: var(--ink-soft);
}

.page-about .version-chip--current {
  border-color: var(--lime);
  color: var(--lime);
  background: rgba(201, 255, 61, .08);
}

.page-about .about-figure--cover {
  margin-top: clamp(26px, 3.6vw, 42px);
}

/* ---------- 接下来的计划 ---------- */
.page-about .next-list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .next-item {
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--green);
  border-radius: 2px;
  padding: 18px 20px;
  min-width: 0;
}

.page-about .next-item h3 {
  margin: 0 0 8px;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .next-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.74;
  color: var(--muted);
}

/* ---------- 收束 ---------- */
.page-about .about-cta {
  margin-top: clamp(40px, 6vw, 76px);
  padding: clamp(26px, 4vw, 52px);
  border: 1px solid var(--line);
  border-radius: 3px;
  background:
    linear-gradient(118deg, rgba(25, 195, 125, .14), rgba(46, 155, 255, .11) 52%, rgba(10, 16, 19, 0) 88%),
    var(--panel);
}

.page-about .about-cta h2 {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(21px, 3vw, 32px);
  line-height: 1.2;
  letter-spacing: -.014em;
}

.page-about .about-cta p {
  margin: 0 0 24px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--ink-soft);
  max-width: 44em;
}

/* ---------- 中屏 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .hero-stat {
    padding: 20px 22px;
  }

  .page-about .next-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .team-layout {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
  }

  .page-about .eco-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 桌面：左侧固定索引 + 右侧宽幅正文 ---------- */
@media (min-width: 1000px) {
  .page-about .about-grid {
    grid-template-columns: minmax(160px, var(--about-rail-w)) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 26px);
    background: transparent;
    border: 0;
    border-right: 1px solid var(--line);
    border-radius: 0;
    padding: 0 22px 0 0;
  }

  .page-about .about-rail-list {
    display: grid;
    gap: 3px;
    overflow: visible;
    padding: 0;
  }

  .page-about .about-rail-link {
    width: 100%;
    background: transparent;
  }

  .page-about .about-rail-scale {
    display: flex;
    flex-direction: column;
    gap: 30px;
    margin-top: 40px;
    padding-left: 1px;
  }

  .page-about .scale-tick {
    position: relative;
    display: block;
    width: 24px;
    height: 1px;
    background: var(--line);
  }

  .page-about .scale-tick::before {
    content: "";
    position: absolute;
    left: 0;
    top: -2px;
    width: 1px;
    height: 5px;
    background: var(--muted);
  }

  .page-about .scale-tick--on {
    background: var(--green);
  }

  .page-about .scale-tick--on::before {
    background: var(--lime);
  }
}

@media (min-width: 1200px) {
  .page-about .about-section-title {
    max-width: 18em;
  }
}

/* ---------- 降低动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail-link,
  .page-about .about-inline-link {
    transition: none;
  }
}