.page-about {
  background-color: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
}

.page-about .mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.page-about .eyebrow {
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--orange-soft);
  margin: 0 0 10px;
}

.page-about .about-figure {
  margin: clamp(24px, 4vw, 40px) 0 0;
}

.page-about .media {
  margin: 0;
  background: var(--ink-2);
  border-radius: var(--radius);
}

.page-about .media img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius);
  object-fit: cover;
}

.page-about .media__caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--muted);
}

/* ---------- 封面 ---------- */
.page-about .about-cover {
  position: relative;
  overflow: hidden;
  padding: clamp(26px, 5vw, 54px) 0 clamp(30px, 5vw, 58px);
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(74, 61, 142, 0.3), transparent 58%),
    radial-gradient(90% 80% at 2% 100%, rgba(255, 138, 61, 0.14), transparent 62%);
}

.page-about .about-cover::before {
  content: "；";
  position: absolute;
  right: -0.06em;
  top: -0.32em;
  font-family: var(--font-display);
  font-size: clamp(200px, 32vw, 440px);
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px var(--ink-3);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-cover__inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(28px, 5vw, 48px);
}

.page-about .about-cover__title {
  font-family: var(--font-display);
  font-size: clamp(38px, 7.4vw, 76px);
  line-height: 1.06;
  letter-spacing: 0.004em;
  color: var(--paper);
  margin: 0 0 20px;
}

.page-about .about-cover__lead {
  margin: 0;
  max-width: 34em;
  font-size: clamp(16px, 1.6vw, 18px);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-cover__navtitle {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--orange-soft);
}

.page-about .about-cover__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-cover__list a {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 9px 12px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  color: var(--paper);
  font-size: 15px;
  text-decoration: none;
  transition: background-color 0.24s ease, border-color 0.24s ease;
}

.page-about .about-cover__list a:hover {
  background: rgba(255, 138, 61, 0.1);
  border-color: rgba(255, 138, 61, 0.4);
}

.page-about .about-cover__list .mono {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--orange);
}

@media (min-width: 900px) {
  .page-about .about-cover__inner {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 72px);
    align-items: end;
  }
}

/* ---------- 主体双列 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 40px);
  padding-bottom: var(--section-y);
}

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

.page-about .about-index__head {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--muted);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .chapter-index__link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 6px 0 6px 13px;
  border-left: 1px solid var(--ink-3);
  color: var(--muted);
  font-size: 13px;
  letter-spacing: 0.04em;
  text-decoration: none;
  transition: color 0.24s ease, border-color 0.24s ease;
}

.page-about .chapter-index__link:hover {
  color: var(--paper);
  border-left-color: var(--orange);
}

.page-about .chapter-index__link[aria-current="true"] {
  color: var(--paper);
  border-left-color: var(--green);
}

.page-about .chapter-index__num {
  font-size: 11px;
  color: var(--ink-3);
  transition: color 0.24s ease;
}

.page-about .chapter-index__link[aria-current="true"] .chapter-index__num {
  color: var(--green);
}

@media (min-width: 1000px) {
  .page-about .about-body {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: clamp(32px, 4vw, 70px);
  }

  .page-about .about-index {
    display: block;
    position: sticky;
    top: 118px;
    align-self: start;
  }
}

/* ---------- 章节 ---------- */
.page-about .chapter {
  position: relative;
  padding: clamp(34px, 5.5vw, 68px) 0;
  border-top: 1px solid var(--ink-3);
}

.page-about .chapter:first-child {
  border-top: 0;
  padding-top: clamp(20px, 3vw, 34px);
}

.page-about .chapter > *:not(.chapter__number) {
  position: relative;
  z-index: 1;
}

.page-about .chapter__number {
  position: absolute;
  top: clamp(4px, 1.2vw, 16px);
  right: 0;
  z-index: 0;
  font-family: var(--font-display);
  font-size: clamp(64px, 11vw, 132px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: transparent;
  -webkit-text-stroke: 1px var(--ink-3);
  pointer-events: none;
  user-select: none;
}

.page-about .chapter__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(25px, 3.6vw, 42px);
  line-height: 1.16;
  letter-spacing: 0.006em;
  color: var(--paper);
  max-width: 20em;
}

.page-about .chapter__body {
  margin-top: clamp(16px, 2.6vw, 26px);
}

.page-about .prose p {
  margin: 0 0 15px;
  max-width: 40em;
  font-size: 17px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.88;
}

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

.page-about .coverage-note {
  margin: clamp(20px, 3vw, 30px) 0 0;
  max-width: 40em;
  font-size: 16px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 起点清单 ---------- */
.page-about .start-list {
  list-style: none;
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 1px;
  display: grid;
  gap: 1px;
  background: var(--ink-3);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .start-list li {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 14px;
  padding: 14px 18px;
  background: var(--ink-2);
  font-size: 15px;
  line-height: 1.7;
  color: var(--paper);
}

.page-about .start-list__k {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--orange);
  padding-top: 4px;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  position: relative;
  list-style: none;
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0 0 0 34px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 10px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--wine), var(--ink-3) 42%, var(--ink-3));
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: clamp(20px, 3vw, 30px);
}

.page-about .timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -34px;
  top: 11px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--ink-3);
  transition: background-color 0.24s ease, border-color 0.24s ease, transform 0.24s ease;
}

.page-about .timeline__item:has(.tl-node[open])::before {
  background: var(--green);
  border-color: var(--green);
  transform: scale(1.14);
}

.page-about .tl-node > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  padding: 4px 0 6px;
  list-style: none;
  cursor: pointer;
  border-radius: var(--radius-sm);
}

.page-about .tl-node > summary::-webkit-details-marker {
  display: none;
}

.page-about .tl-node > summary:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 4px;
}

.page-about .tl-node > summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--green);
}

.page-about .tl-node[open] > summary::after {
  content: "−";
}

.page-about .tl-node__year {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--orange-soft);
}

.page-about .tl-node[open] .tl-node__year {
  color: var(--orange);
}

.page-about .tl-node__title {
  flex: 1 1 auto;
  font-size: clamp(16px, 1.8vw, 19px);
  font-weight: 600;
  color: var(--paper);
}

.page-about .tl-node__body {
  padding: 2px 0 6px;
}

.page-about .tl-node__body p {
  margin: 0;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 团队分层 ---------- */
.page-about .team-layers {
  display: grid;
  gap: 10px;
  margin: clamp(22px, 3vw, 34px) 0 0;
}

.page-about .team-layer {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 15px 18px;
  border: 1px solid var(--ink-3);
  border-radius: var(--radius-sm);
  background: var(--ink-2);
}

.page-about .team-layer__num {
  font-family: var(--font-mono);
  font-size: 26px;
  line-height: 1;
  color: var(--paper);
}

.page-about .team-layer__text {
  font-size: 15px;
  color: var(--paper);
  opacity: 0.86;
}

.page-about .team-layer--edit {
  border-color: rgba(255, 138, 61, 0.42);
  background: linear-gradient(90deg, rgba(255, 138, 61, 0.18), transparent 74%), var(--ink-2);
  margin-left: clamp(0px, 2vw, 24px);
}

.page-about .team-layer--edit .team-layer__num {
  color: var(--orange);
}

.page-about .team-layer--obs {
  border-color: rgba(47, 224, 138, 0.36);
  background: linear-gradient(90deg, rgba(47, 224, 138, 0.14), transparent 74%), var(--ink-2);
  margin-left: clamp(0px, 4vw, 48px);
}

.page-about .team-layer--obs .team-layer__num {
  color: var(--green);
}

.page-about .flow-list {
  list-style: none;
  margin: clamp(26px, 3.4vw, 38px) 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .flow-list li {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 14px;
  padding-top: 16px;
  border-top: 1px solid var(--ink-3);
}

.page-about .flow-list__step {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--orange);
  padding-top: 5px;
}

.page-about .flow-list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--muted);
}

/* ---------- 数据条带 ---------- */
.page-about .stat-band {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 1px;
  background: var(--ink-3);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .stat-band__cell {
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  gap: 8px;
  padding: clamp(18px, 3vw, 26px);
  background: var(--ink-2);
}

.page-about .stat-band__num {
  font-family: var(--font-mono);
  font-size: clamp(28px, 3.6vw, 40px);
  line-height: 1.05;
  color: var(--paper);
}

.page-about .stat-band__unit {
  font-size: 15px;
  margin-left: 4px;
  color: var(--green);
}

.page-about .stat-band__label {
  font-size: 13px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--muted);
}

@media (min-width: 760px) {
  .page-about .stat-band {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 四川地域块 ---------- */
.page-about .region-block {
  position: relative;
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  margin-top: clamp(20px, 3vw, 30px);
  padding: clamp(22px, 3.4vw, 40px) clamp(20px, 3.4vw, 38px) clamp(22px, 3.4vw, 40px) clamp(26px, 3.8vw, 44px);
  border: 1px solid rgba(232, 183, 122, 0.32);
  border-radius: var(--radius);
  background: linear-gradient(140deg, rgba(232, 183, 122, 0.16), rgba(11, 27, 43, 0) 62%), var(--ink-2);
}

.page-about .region-block::before {
  content: "";
  position: absolute;
  left: 0;
  top: clamp(22px, 3.4vw, 40px);
  bottom: clamp(22px, 3.4vw, 40px);
  width: 4px;
  border-radius: 4px;
  background: var(--sand);
}

.page-about .region-block__text p {
  margin: 0 0 14px;
  max-width: 36em;
  font-size: 17px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.88;
}

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

.page-about .region-block__media {
  width: 100%;
  max-width: 320px;
}

@media (min-width: 860px) {
  .page-about .region-block {
    grid-template-columns: minmax(0, 1fr) 300px;
    align-items: center;
  }

  .page-about .region-block__media {
    max-width: none;
  }
}

/* ---------- 协作卡片 ---------- */
.page-about .about-grid {
  margin-top: clamp(22px, 3vw, 32px);
  gap: clamp(14px, 2vw, 22px);
}

.page-about .about-grid .card {
  padding: clamp(20px, 2.6vw, 28px);
  border-radius: var(--radius);
  border: 1px solid var(--ink-3);
  background: var(--ink-2);
}

.page-about .about-grid .card--warm {
  border-color: rgba(255, 138, 61, 0.36);
}

.page-about .about-grid .card--cool {
  border-color: rgba(47, 224, 138, 0.32);
}

.page-about .about-grid .card__label {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.page-about .about-grid .card--warm .card__label {
  color: var(--orange);
}

.page-about .about-grid .card--cool .card__label {
  color: var(--green);
}

.page-about .about-grid .card__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(19px, 2.2vw, 24px);
  line-height: 1.25;
  color: var(--paper);
}

.page-about .about-grid .card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-next {
  border-bottom: 1px solid var(--ink-3);
}

.page-about .next-links {
  display: grid;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 34px);
}

.page-about .next-link {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-rows: auto auto;
  column-gap: 16px;
  row-gap: 6px;
  padding: 18px 20px;
  border: 1px solid var(--ink-3);
  border-radius: var(--radius);
  background: var(--ink-2);
  color: var(--paper);
  text-decoration: none;
  transition: border-color 0.24s ease, background-color 0.24s ease, transform 0.24s ease;
}

.page-about .next-link:hover {
  border-color: var(--green);
  background: var(--ink-3);
  transform: translateY(-2px);
}

.page-about .next-link__k {
  grid-row: span 2;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--orange);
  padding-top: 3px;
}

.page-about .next-link__t {
  font-size: 17px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .next-link__d {
  font-size: 14px;
  line-height: 1.65;
  color: var(--muted);
}

@media (min-width: 720px) {
  .page-about .next-links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}