.page-about {
  --about-spine-w: 56px;
  --about-aside-w: 220px;
  background: var(--pitch-ink);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(18px, 3vw, 28px) var(--gutter) 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--smoke);
}
.page-about .about-crumbs .breadcrumb__link {
  color: var(--cyan-muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease);
}
.page-about .about-crumbs .breadcrumb__link:hover {
  color: var(--neon-cyan);
  border-bottom-color: var(--neon-cyan);
}
.page-about .about-crumbs .breadcrumb__sep {
  color: var(--turf-line);
}
.page-about .about-crumbs .breadcrumb__item {
  color: var(--chalk);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(36px, 7vw, 96px) 0 clamp(32px, 6vw, 72px);
  background:
    radial-gradient(120% 95% at 88% -10%, rgba(31, 169, 138, 0.18), transparent 62%),
    radial-gradient(80% 70% at 0% 100%, rgba(255, 90, 31, 0.07), transparent 60%),
    var(--pitch-ink);
  overflow: hidden;
}
.page-about .about-hero__inner {
  display: grid;
  gap: clamp(28px, 5vw, 52px);
  align-items: center;
}
.page-about .about-hero h1 {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(29px, 5vw, 52px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--chalk);
  max-width: 15em;
}
.page-about .about-hero .lede {
  margin: 20px 0 0;
  max-width: 34em;
  font-family: var(--font-serif);
  font-size: clamp(15px, 1.55vw, 17.5px);
  line-height: 1.95;
  color: rgba(242, 247, 243, 0.88);
}
.page-about .about-hero__facts {
  margin-top: clamp(26px, 4vw, 42px);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--turf-line);
  border: 1px solid var(--turf-line);
  max-width: 640px;
}
.page-about .about-fact {
  background: var(--pitch-ink);
  padding: 14px 15px 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.page-about .about-fact__v {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(20px, 2.6vw, 27px);
  font-weight: 600;
  line-height: 1;
  color: var(--neon-cyan);
}
.page-about .about-fact__v--flare {
  color: var(--flare-orange);
}
.page-about .about-fact__k {
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0.04em;
  color: var(--smoke);
}
.page-about .about-hero__media {
  margin: 0;
}
.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 长文画布与时间脊 ---------- */
.page-about .about-body {
  position: relative;
}
.page-about .about-body__inner {
  position: relative;
  padding-top: clamp(40px, 6vw, 76px);
  padding-bottom: clamp(48px, 8vw, 100px);
}
.page-about .about-body__inner::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: calc(var(--gutter) + 28px);
  width: 1px;
  display: none;
  background: linear-gradient(180deg, transparent, var(--turf-line) 6%, var(--turf-line) 94%, transparent);
  pointer-events: none;
}

.page-about .about-chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  row-gap: 22px;
  padding: clamp(36px, 5vw, 66px) 0;
}
.page-about .about-chapter + .about-chapter {
  border-top: 1px solid rgba(23, 69, 46, 0.65);
}
.page-about .about-chapter__body {
  min-width: 0;
}
.page-about .about-chapter__title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(21px, 3vw, 33px);
  line-height: 1.28;
  letter-spacing: -0.005em;
  color: var(--chalk);
  max-width: 24em;
}
.page-about .about-chapter .prose p {
  margin: 18px 0 0;
  max-width: 38em;
  font-size: 15.5px;
  line-height: 1.85;
  color: rgba(242, 247, 243, 0.82);
}
.page-about .about-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  color: var(--neon-cyan);
}

.page-about .about-spine {
  display: none;
}

.page-about .about-aside {
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-width: 0;
}
.page-about .about-aside__k {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan-muted);
}
.page-about .about-aside__v {
  margin: 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--smoke);
}

/* ---------- 图 ---------- */
.page-about .about-figure {
  margin: clamp(24px, 3vw, 32px) 0 0;
}
.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .about-banner {
  margin: clamp(30px, 4vw, 46px) 0;
  border-top: 1px solid var(--turf-line);
  border-bottom: 1px solid var(--turf-line);
  overflow: hidden;
}
.page-about .about-banner img {
  display: block;
  width: 100%;
  height: clamp(130px, 20vw, 250px);
  object-fit: cover;
  opacity: 0.7;
}

/* ---------- 对照表 ---------- */
.page-about .about-table-wrap {
  margin-top: clamp(24px, 3vw, 30px);
  border: 1px solid var(--turf-line);
  background: var(--card-slate);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}
.page-about .about-table {
  width: 100%;
  min-width: 600px;
  border-collapse: collapse;
  font-size: 14px;
}
.page-about .about-table caption {
  text-align: left;
}
.page-about .about-table th,
.page-about .about-table td {
  text-align: left;
  padding: 14px 16px;
  border-bottom: 1px solid var(--turf-line);
  vertical-align: top;
  line-height: 1.7;
}
.page-about .about-table thead th {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cyan-muted);
  background: rgba(12, 42, 28, 0.65);
}
.page-about .about-table tbody th {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--neon-cyan);
  white-space: nowrap;
}
.page-about .about-table tbody td {
  color: rgba(242, 247, 243, 0.78);
}
.page-about .about-table tbody tr {
  transition: background var(--t-fast) var(--ease), box-shadow var(--t-fast) var(--ease);
}
.page-about .about-table tbody tr:hover {
  background: rgba(52, 245, 197, 0.07);
  box-shadow: inset 2px 0 0 var(--neon-cyan);
}
.page-about .about-table tbody tr:last-child th,
.page-about .about-table tbody tr:last-child td {
  border-bottom: 0;
}

/* ---------- 浅色引用块 ---------- */
.page-about .about-quote {
  margin: clamp(24px, 3vw, 32px) 0 0;
  padding: 22px 24px;
  max-width: 42em;
  background: var(--whistle);
  color: var(--ink-on-light);
  border-left: 4px solid var(--neon-cyan);
  font-family: var(--font-serif);
  font-size: 16px;
  line-height: 1.9;
}
.page-about .about-quote p {
  margin: 0;
}

/* ---------- 时间节点轨 ---------- */
.page-about .about-track {
  margin-top: clamp(22px, 3vw, 30px);
  border-top: 1px solid var(--turf-line);
}
.page-about .about-node {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 16px;
  padding: 16px 0;
  border-bottom: 1px solid var(--turf-line);
}
.page-about .about-node__stage {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.03em;
  line-height: 1.7;
  color: var(--flare-soft);
}
.page-about .about-node__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(242, 247, 243, 0.8);
}

/* ---------- 团队分工 ---------- */
.page-about .about-roles {
  margin-top: clamp(22px, 3vw, 30px);
  display: grid;
  gap: 1px;
  background: var(--turf-line);
  border: 1px solid var(--turf-line);
}
.page-about .about-role {
  background: var(--card-slate);
  padding: 18px 20px 20px;
  transition: background var(--t-fast) var(--ease), box-shadow var(--t-fast) var(--ease);
}
.page-about .about-role:hover,
.page-about .about-role:focus-within {
  background: var(--turf-deep);
  box-shadow: inset 0 0 0 1px rgba(52, 245, 197, 0.3);
}
.page-about .about-role__summary {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  list-style: none;
  cursor: pointer;
}
.page-about .about-role__summary::-webkit-details-marker {
  display: none;
}
.page-about .about-role__summary::after {
  content: "";
  flex: 0 0 auto;
  width: 8px;
  height: 8px;
  border-right: 1px solid var(--cyan-muted);
  border-bottom: 1px solid var(--cyan-muted);
  transform: rotate(45deg);
  transition: transform var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease);
}
.page-about .about-role[open] .about-role__summary::after {
  transform: rotate(-135deg);
  border-color: var(--neon-cyan);
}
.page-about .about-role__name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--chalk);
}
.page-about .about-role__count {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 19px;
  font-weight: 600;
  color: var(--flare-orange);
  margin-left: auto;
}
.page-about .about-role__desc {
  margin: 12px 0 0;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(242, 247, 243, 0.75);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-next {
  margin-top: clamp(40px, 6vw, 74px);
  padding-top: clamp(28px, 4vw, 42px);
  border-top: 1px solid var(--turf-line);
}
.page-about .about-next__title {
  margin: 0 0 20px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan-muted);
}
.page-about .about-next__grid {
  display: grid;
  gap: 1px;
  background: var(--turf-line);
  border: 1px solid var(--turf-line);
}
.page-about .about-next__item {
  display: block;
  padding: 22px 22px 26px;
  background: var(--pitch-ink);
  text-decoration: none;
  transition: background var(--t-fast) var(--ease), box-shadow var(--t-fast) var(--ease);
}
.page-about .about-next__item:hover,
.page-about .about-next__item:focus-visible {
  background: var(--card-slate);
  box-shadow: inset 0 0 0 1px rgba(52, 245, 197, 0.32);
}
.page-about .about-next__k {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--flare-orange);
}
.page-about .about-next__t {
  display: block;
  margin-top: 10px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--chalk);
}
.page-about .about-next__d {
  display: block;
  margin-top: 8px;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--smoke);
}

/* ---------- 中屏 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-node {
    grid-template-columns: 130px minmax(0, 1fr);
    gap: 26px;
  }
  .page-about .about-roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-next__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 桌面：三轨栅格 + 时间脊 ---------- */
@media (min-width: 900px) {
  .page-about .about-body__inner::before {
    display: block;
  }
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.82fr);
  }
  .page-about .about-chapter {
    grid-template-columns: var(--about-spine-w) minmax(0, 1fr);
    column-gap: 32px;
    row-gap: 0;
  }
  .page-about .about-spine {
    display: block;
    position: relative;
    padding-top: 10px;
  }
  .page-about .about-spine::after {
    content: "";
    position: absolute;
    left: 50%;
    top: 16px;
    width: 9px;
    height: 9px;
    margin-left: -4.5px;
    border-radius: 50%;
    background: var(--pitch-ink);
    border: 1px solid var(--turf-line);
    transition: background var(--t-fast) var(--ease),
      border-color var(--t-fast) var(--ease),
      box-shadow var(--t-fast) var(--ease);
  }
  .page-about .about-spine.is-in::after {
    background: var(--neon-cyan);
    border-color: var(--neon-cyan);
    box-shadow: 0 0 0 4px rgba(52, 245, 197, 0.13);
  }
  .page-about .about-aside {
    grid-column: 2;
    margin-top: 4px;
  }
}

/* ---------- 宽屏：旁注栏独立成第三轨 ---------- */
@media (min-width: 1120px) {
  .page-about .about-chapter {
    grid-template-columns: var(--about-spine-w) minmax(0, 1fr) var(--about-aside-w);
  }
  .page-about .about-aside {
    grid-column: 3;
    margin-top: 0;
    border-left: 1px solid var(--turf-line);
    padding-left: 18px;
    align-self: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-table tbody tr,
  .page-about .about-role,
  .page-about .about-next__item,
  .page-about .about-spine::after,
  .page-about .about-role__summary::after,
  .page-about .about-crumbs .breadcrumb__link {
    transition: none;
  }
}