.page-about {
  --about-gap: clamp(30px, 4.4vw, 62px);
  --about-pad: clamp(20px, 3vw, 36px);
}

.page-about .shell {
  display: grid;
  gap: var(--about-gap);
  padding-top: clamp(20px, 3vw, 40px);
  padding-bottom: clamp(40px, 6vw, 88px);
}

.page-about .breadcrumbs {
  font-size: 13px;
}

/* ---------- 首屏：主题声明 + 数据速览 + 内容目录 ---------- */

.page-about .about-intro {
  display: grid;
  gap: 18px;
}

.page-about .about-intro h1 {
  margin: 0;
  max-width: 22ch;
  font-size: clamp(30px, 5.6vw, 56px);
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--text-strong);
}

.page-about .about-intro .lede {
  margin: 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.8;
  color: var(--text);
}

.page-about .intro-keys {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-panel);
  overflow: hidden;
}

.page-about .intro-key {
  display: grid;
  gap: 8px;
  padding: 18px 20px;
  background: var(--ink-700);
}

.page-about .intro-key__num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 4.4vw, 40px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--amber-500);
}

.page-about .intro-key__label {
  font-size: 13px;
  line-height: 1.5;
  color: var(--mist-400);
}

.page-about .about-index {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  margin-top: 6px;
}

.page-about .about-index__item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 18px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line);
  background: rgba(53, 242, 208, 0.03);
  color: var(--text);
  font-size: 14px;
  text-decoration: none;
  transition: background var(--ease), border-color var(--ease), transform var(--ease);
}

.page-about .about-index__item .mono {
  font-size: 12px;
  color: var(--cyan-500);
}

.page-about .about-index__item:hover,
.page-about .about-index__item:focus-visible {
  background: rgba(53, 242, 208, 0.1);
  border-color: var(--cyan-500);
  transform: translateY(-2px);
}

/* ---------- 定位：奶油纸长文面板 ---------- */

.page-about .about-claim .panel-head .eyebrow--paper {
  color: var(--brick-600);
}

.page-about .about-claim .section-title {
  color: var(--brown-900);
}

.page-about .claim-grid {
  display: grid;
  gap: 18px;
  max-width: 76ch;
}

.page-about .claim-grid p {
  margin: 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--brown-900);
}

.page-about .claim-grid .claim-lead {
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.7;
  font-weight: 600;
}

.page-about .claim-points {
  display: grid;
  gap: 14px;
  margin: 4px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .claim-points li {
  padding-left: 18px;
  border-left: 3px solid var(--brick-600);
  font-size: 15px;
  line-height: 1.75;
  color: var(--brown-900);
}

.page-about .claim-points__t {
  display: block;
  margin-bottom: 4px;
  font-weight: 700;
  letter-spacing: 0.02em;
}

/* ---------- 团队与岗位分工 ---------- */

.page-about .team-grid {
  display: grid;
  gap: 22px;
}

.page-about .media-frame img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-about .team-cap {
  margin: 12px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist-400);
}

.page-about .role-grid {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .role {
  display: grid;
  gap: 8px;
  padding: 20px;
  border-radius: 22px;
  background: var(--panel-600);
  border: 1px solid transparent;
  transition: border-color var(--ease), background var(--ease), box-shadow var(--ease), transform var(--ease);
}

.page-about .role:hover,
.page-about .role:focus-within {
  border-color: var(--cyan-500);
  background: #242b31;
  box-shadow: 0 20px 44px -32px rgba(53, 242, 208, 0.85);
  transform: translateY(-2px);
}

.page-about .role__name {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin: 0;
  font-size: 16px;
  color: var(--text-strong);
}

.page-about .role__num {
  font-family: var(--font-mono);
  font-size: 30px;
  line-height: 1;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--amber-500);
}

.page-about .role__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text);
}

/* ---------- 数据来源与校对流程 ---------- */

.page-about .flow {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-panel);
  overflow: hidden;
}

.page-about .flow-step {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 8px 18px;
  padding: 22px var(--about-pad);
  background: var(--ink-700);
}

.page-about .flow-step__no {
  grid-row: span 2;
  padding-top: 4px;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--cyan-500);
}

.page-about .flow-step__title {
  margin: 0;
  font-size: clamp(16px, 1.8vw, 19px);
  letter-spacing: -0.01em;
  color: var(--text-strong);
}

.page-about .flow-step__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text);
}

.page-about .source-figure {
  display: grid;
  gap: 10px;
  margin: 24px 0 0;
}

.page-about .source-figure figcaption,
.page-about .history-figure figcaption {
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist-400);
}

/* ---------- 发展历程时间线 ---------- */

.page-about .history-grid {
  display: grid;
  gap: 28px;
}

.page-about .timeline {
  display: grid;
  gap: 14px;
}

.page-about .tl-node {
  position: relative;
  padding-left: 34px;
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 17px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 2px solid var(--cyan-500);
  box-shadow: 0 0 0 4px rgba(53, 242, 208, 0.1);
  z-index: 2;
  transition: background var(--ease), box-shadow var(--ease);
}

.page-about .tl-node::after {
  content: "";
  position: absolute;
  left: 11px;
  top: 34px;
  bottom: -16px;
  width: 2px;
  background: linear-gradient(180deg, rgba(53, 242, 208, 0.42), rgba(53, 242, 208, 0.04));
  z-index: 1;
}

.page-about .tl-node:last-child::after {
  display: none;
}

.page-about .tl-node[open]::before {
  background: var(--cyan-500);
  box-shadow: 0 0 0 5px rgba(53, 242, 208, 0.2);
}

.page-about .tl-sum {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
  padding: 14px 18px;
  list-style: none;
  cursor: pointer;
  border-radius: 18px;
  background: var(--panel-600);
  border: 1px solid transparent;
  transition: border-color var(--ease), background var(--ease), border-radius var(--ease);
}

.page-about .tl-sum::-webkit-details-marker {
  display: none;
}

.page-about .tl-sum:hover,
.page-about .tl-sum:focus-visible {
  border-color: rgba(53, 242, 208, 0.5);
}

.page-about .tl-node[open] > .tl-sum {
  border-color: var(--cyan-500);
  background: #242b31;
  border-radius: 18px 18px 0 0;
}

.page-about .tl-stage {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--cyan-500);
}

.page-about .tl-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-strong);
}

.page-about .tl-sum .badge {
  margin-left: auto;
}

.page-about .tl-body {
  padding: 16px 18px 20px;
  background: #242b31;
  border: 1px solid var(--cyan-500);
  border-top: none;
  border-radius: 0 0 18px 18px;
}

.page-about .tl-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--text);
}

.page-about .tl-body a {
  color: var(--cyan-300);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .history-figure {
  display: grid;
  gap: 10px;
  margin: 0;
}

.page-about .history-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  border-radius: 24px;
  border: 1px solid var(--line);
  object-fit: cover;
}

/* ---------- 合作与覆盖 ---------- */

.page-about .partner-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .partner {
  padding: 24px 22px;
  border-radius: 24px;
  background: linear-gradient(158deg, rgba(53, 242, 208, 0.1), rgba(53, 242, 208, 0.015) 62%);
  border: 1px solid var(--line);
}

.page-about .partner__name {
  margin: 0 0 14px;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--mist-400);
}

.page-about .partner__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(34px, 5vw, 48px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--amber-500);
}

.page-about .partner__text {
  margin: 14px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text);
}

.page-about .coverage {
  margin-top: 20px;
  padding: 24px 22px;
  border-radius: 24px;
  background: var(--ink-700);
  border: 1px solid var(--line-soft);
}

.page-about .coverage__lead {
  margin: 0 0 16px;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--cyan-500);
}

.page-about .coverage-list {
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .coverage-list li {
  display: grid;
  gap: 5px;
  padding-bottom: 16px;
  border-bottom: 1px dashed var(--line-soft);
}

.page-about .coverage-list li:last-child {
  padding-bottom: 0;
  border-bottom: none;
}

.page-about .coverage-list__k {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist-400);
}

.page-about .coverage-list__v {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-strong);
}

.page-about .coverage-list__v .num {
  font-family: var(--font-mono);
  color: var(--amber-500);
  font-weight: 700;
}

/* ---------- 复盘深度分级 ---------- */

.page-about .level-stack {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .level {
  position: relative;
  overflow: hidden;
  padding: 26px 22px 24px;
  border-radius: 24px;
  background: var(--ink-700);
  border: 1px solid var(--line-soft);
  transition: transform var(--ease), border-color var(--ease);
}

.page-about .level::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--cyan-500), rgba(53, 242, 208, 0));
}

.page-about .level:nth-child(2)::before {
  background: linear-gradient(90deg, var(--amber-500), rgba(242, 166, 59, 0));
}

.page-about .level:nth-child(3)::before {
  background: linear-gradient(90deg, var(--brick-600), rgba(196, 85, 58, 0));
}

.page-about .level:hover,
.page-about .level:focus-within {
  transform: translateY(-3px);
  border-color: var(--line);
}

.page-about .level__idx {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--mist-400);
}

.page-about .level__name {
  margin: 10px 0 10px;
  font-size: clamp(18px, 2vw, 22px);
  letter-spacing: -0.01em;
  color: var(--text-strong);
}

.page-about .level__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--text);
}

/* ---------- 延伸入口 ---------- */

.page-about .about-next {
  display: grid;
  gap: 18px;
}

.page-about .about-next .section-title {
  margin: 0;
}

.page-about .next-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .next-card {
  display: grid;
  gap: 8px;
  padding: 24px 22px;
  border-radius: 26px;
  background: var(--ink-700);
  border: 1px solid var(--line);
  text-decoration: none;
  color: inherit;
  transition: background var(--ease), border-color var(--ease), transform var(--ease), box-shadow var(--ease);
}

.page-about .next-card:hover,
.page-about .next-card:focus-visible {
  background: #1c222a;
  border-color: var(--cyan-500);
  transform: translateY(-3px);
  box-shadow: 0 26px 50px -38px rgba(53, 242, 208, 0.9);
}

.page-about .next-card__k {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--cyan-500);
}

.page-about .next-card__t {
  font-size: 17px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--text-strong);
}

.page-about .next-card__d {
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist-400);
}

/* ---------- 窄屏兜底 ---------- */

@media (max-width: 559px) {
  .page-about .about-intro h1 {
    max-width: none;
  }

  .page-about .flow-step {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .flow-step__no {
    grid-row: auto;
    padding-top: 0;
  }

  .page-about .tl-sum {
    padding: 13px 14px;
  }

  .page-about .tl-title {
    font-size: 15px;
  }

  .page-about .about-index__item,
  .page-about .coverage-list__v,
  .page-about .next-card__d {
    overflow-wrap: anywhere;
  }
}

/* ---------- 平板 ---------- */

@media (min-width: 620px) {
  .page-about .intro-keys {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-index {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 桌面 ---------- */

@media (min-width: 900px) {
  .page-about .about-index {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 1fr);
    align-items: start;
    gap: 26px;
  }

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

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

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

@media (min-width: 980px) {
  .page-about .history-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 300px);
    align-items: start;
    gap: 32px;
  }

  .page-about .coverage-list li {
    grid-template-columns: 140px minmax(0, 1fr);
    align-items: baseline;
    gap: 18px;
  }
}