.page-about {
  --ab-num-size: clamp(2.4rem, 6vw, 3.6rem);
  --ab-node-line: #24304D;
  display: block;
  background: var(--ink);
  color: var(--paper);
  overflow-x: hidden;
}

.page-about .about-intro {
  position: relative;
  padding-block: clamp(28px, 5vw, 52px) clamp(44px, 7vw, 86px);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(130% 90% at 86% -10%, rgba(34, 224, 214, 0.13), transparent 62%),
    radial-gradient(90% 70% at 4% 112%, rgba(110, 30, 60, 0.30), transparent 70%),
    linear-gradient(180deg, var(--ink-2) 0%, var(--ink) 82%);
}

.page-about .about-intro-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 5vw, 56px);
  align-items: start;
}

.page-about .about-kicker {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-intro h1 {
  margin: 0 0 clamp(16px, 2.4vw, 24px);
  max-width: 22ch;
  font-size: clamp(1.9rem, 5.6vw, 3.35rem);
  font-weight: 800;
  line-height: 1.14;
  letter-spacing: -0.01em;
}

.page-about .about-lead {
  margin: 0 0 clamp(22px, 3.5vw, 34px);
  max-width: 48ch;
  font-size: clamp(15px, 1.3vw, 17px);
  line-height: 1.9;
  color: var(--mist);
}

.page-about .about-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 30px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-facts li {
  position: relative;
  padding-left: 15px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--mist);
}

.page-about .about-facts li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 6px;
  height: 6px;
  margin-top: -3px;
  background: var(--orange);
  transform: rotate(45deg);
}

.page-about .about-toc {
  position: relative;
  padding: clamp(18px, 3vw, 26px);
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(14, 23, 48, 0.92), rgba(7, 11, 28, 0.78));
  box-shadow: 7px 7px 0 0 rgba(36, 48, 77, 0.5);
}

.page-about .about-toc-title {
  margin: 0 0 14px;
  padding-bottom: 10px;
  border-bottom: 1px dashed var(--line);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--mist);
}

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

.page-about .about-toc-list a {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 10px;
  align-items: baseline;
  padding: 9px 8px;
  border-left: 2px solid transparent;
  color: var(--paper);
  text-decoration: none;
  transition: background-color 180ms ease, border-color 180ms ease, color 180ms ease;
}

.page-about .about-toc-list a:hover,
.page-about .about-toc-list a:focus-visible {
  border-left-color: var(--cyan);
  background: rgba(34, 224, 214, 0.08);
  color: var(--cyan);
}

.page-about .toc-idx {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--orange);
}

.page-about .toc-label {
  font-size: 14.5px;
}

/* ---------- 章节骨架 ---------- */

.page-about .about-sec {
  position: relative;
  padding-block: clamp(52px, 8vw, 104px);
}

.page-about .about-sec--locate {
  background: var(--ink);
}

.page-about .about-sec--versions {
  background: var(--ink-2);
  border-block: 1px solid var(--line);
}

.page-about .about-sec--correction {
  background:
    radial-gradient(85% 100% at 102% 0%, rgba(58, 42, 107, 0.48), transparent 66%),
    var(--ink);
}

.page-about .about-sec--team {
  background: var(--ink-2);
  border-block: 1px solid var(--line);
}

.page-about .about-sec--range {
  background:
    linear-gradient(118deg, rgba(110, 30, 60, 0.55) 0%, rgba(14, 23, 48, 0.85) 58%, var(--ink) 100%);
  border-block: 1px solid var(--wine);
}

.page-about .about-sec--eco {
  background: var(--ink);
}

.page-about .about-sec-head {
  display: grid;
  gap: 10px;
  max-width: 760px;
  margin-bottom: clamp(26px, 4vw, 46px);
}

.page-about .about-sec-head .chapter-index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.26em;
  color: var(--cyan);
}

.page-about .about-sec-head .chapter-title {
  margin: 0;
  font-size: clamp(1.45rem, 3.6vw, 2.3rem);
  font-weight: 700;
  line-height: 1.26;
  letter-spacing: -0.005em;
}

.page-about .about-sec-head .chapter-band {
  width: clamp(56px, 12vw, 116px);
  height: 3px;
  margin-top: 6px;
  background: linear-gradient(90deg, var(--indigo), var(--wine));
}

.page-about .about-sec--correction .chapter-band {
  background: linear-gradient(90deg, var(--indigo), var(--cyan));
}

.page-about .about-sec--team .chapter-band {
  background: linear-gradient(90deg, var(--wine), var(--orange));
}

.page-about .about-sec--range .chapter-band {
  background: var(--wine);
}

.page-about .about-sec--eco .chapter-band {
  background: linear-gradient(90deg, var(--cyan), var(--indigo));
}

.page-about .about-para {
  max-width: 68ch;
  margin: 0 0 clamp(26px, 4vw, 44px);
  font-size: clamp(15px, 1.2vw, 17px);
  line-height: 1.92;
  color: var(--mist);
}

/* ---------- 01 定位 ---------- */

.page-about .scope-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(18px, 3vw, 32px);
}

.page-about .scope-col {
  padding: clamp(20px, 3vw, 30px);
  border: 1px solid var(--line);
  background: rgba(14, 23, 48, 0.5);
}

.page-about .scope-col--do {
  border-top: 3px solid var(--cyan);
}

.page-about .scope-col--dont {
  border-top: 3px solid var(--wine);
}

.page-about .scope-title {
  margin: 0 0 14px;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.01em;
}

.page-about .scope-list {
  display: grid;
  gap: 11px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .scope-list li {
  position: relative;
  padding-left: 18px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .scope-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  background: currentColor;
  opacity: 0.65;
  transform: rotate(45deg);
}

/* ---------- 02 迭代长卷 ---------- */

.page-about .versions-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 48px);
  align-items: start;
}

.page-about .filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 12px;
}

.page-about .filter-live {
  margin: 0 0 clamp(20px, 3vw, 30px);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .version-track {
  position: relative;
  display: grid;
  gap: clamp(14px, 2.2vw, 22px);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .version-node {
  position: relative;
  display: grid;
  gap: 4px;
  padding: clamp(18px, 2.6vw, 26px) clamp(18px, 2.6vw, 28px);
  border-left: 2px solid var(--ab-node-line);
  background: rgba(7, 11, 28, 0.55);
}

.page-about .version-node::before {
  content: "";
  position: absolute;
  left: -7px;
  top: clamp(26px, 3vw, 34px);
  width: 12px;
  height: 12px;
  background: var(--ink);
  border: 2px solid var(--indigo);
  transform: rotate(45deg);
}

.page-about .version-node--current {
  border-left-color: var(--orange);
  background: rgba(255, 106, 43, 0.07);
}

.page-about .version-node--current::before {
  border-color: var(--orange);
  background: var(--orange);
}

.page-about .version-index {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.25rem, 2.4vw, 1.6rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--cyan);
}

.page-about .version-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
}

.page-about .version-name {
  margin: 0;
  font-size: 1.0625rem;
  font-weight: 700;
}

.page-about .version-desc {
  margin: 8px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.82;
  color: var(--mist);
}

.page-about .paper-tag[data-ability] {
  position: relative;
  cursor: default;
}

.page-about .versions-aside .media-frame {
  margin: 0;
}

@media (hover: hover) {
  .page-about .paper-tag[data-ability]::after {
    content: attr(data-ability);
    position: absolute;
    left: 0;
    bottom: calc(100% + 8px);
    z-index: 6;
    width: max-content;
    max-width: min(240px, 62vw);
    padding: 8px 10px;
    font-family: var(--font-sans);
    font-size: 12.5px;
    line-height: 1.6;
    color: var(--paper);
    background: #1A2440;
    border: 1px solid var(--line);
    opacity: 0;
    visibility: hidden;
    transform: translateY(4px);
    transition: opacity 160ms ease, transform 160ms ease, visibility 160ms;
    pointer-events: none;
  }

  .page-about .paper-tag[data-ability]:hover::after {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
}

/* ---------- 03 校正流程 ---------- */

.page-about .flow-svg {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  margin-bottom: clamp(24px, 4vw, 40px);
}

.page-about .correction-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 4vw, 46px);
  align-items: start;
}

.page-about .correction-steps {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  counter-reset: cstep;
  list-style: none;
}

.page-about .correction-steps li {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: 12px;
  padding-bottom: 14px;
  border-bottom: 1px dashed var(--line);
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
  counter-increment: cstep;
}

.page-about .correction-steps li::before {
  content: counter(cstep, decimal-leading-zero);
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--orange);
}

.page-about .correction-steps strong {
  color: var(--paper);
  font-weight: 700;
}

.page-about .correction-grid .media-frame {
  margin: 0;
}

/* ---------- 04 团队 ---------- */

.page-about .team-rows {
  margin: 0 0 clamp(26px, 4vw, 42px);
  padding: 0;
  border-top: 1px solid var(--line);
  list-style: none;
}

.page-about .team-row {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 6px 18px;
  align-items: baseline;
  padding: clamp(16px, 2.4vw, 24px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .team-num {
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 3.4vw, 2.4rem);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
}

.page-about .team-role {
  font-size: 1rem;
  font-weight: 700;
}

.page-about .team-desc {
  grid-column: 2;
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .team-figure {
  margin: 0;
}

/* ---------- 05 服务范围 ---------- */

.page-about .range-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 4vw, 50px);
  align-items: start;
}

.page-about .range-stats {
  display: grid;
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .range-stats li {
  display: grid;
  gap: 4px;
  padding-bottom: 16px;
  border-bottom: 1px solid rgba(244, 239, 230, 0.16);
}

.page-about .range-num {
  font-family: var(--font-mono);
  font-size: var(--ab-num-size);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--orange);
}

.page-about .range-unit {
  font-size: 14px;
  line-height: 1.7;
  color: var(--paper);
}

.page-about .range-copy p {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.9;
  color: var(--mist);
}

.page-about .range-contact {
  display: grid;
  gap: 0;
  margin: 22px 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
  list-style: none;
}

.page-about .range-contact li {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 12px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .rc-key {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

.page-about .rc-val {
  font-size: 14px;
  line-height: 1.7;
  color: var(--paper);
  overflow-wrap: anywhere;
}

/* ---------- 06 合作生态 ---------- */

.page-about .eco-list {
  border-top: 1px solid var(--line);
}

.page-about .eco-item {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  padding: clamp(18px, 3vw, 28px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .eco-name {
  margin: 0;
  font-size: 1.0625rem;
  font-weight: 700;
  line-height: 1.5;
}

.page-about .eco-text {
  margin: 0;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .eco-tail {
  margin: clamp(26px, 4vw, 40px) 0 0;
  max-width: 74ch;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--mist);
}

.page-about .eco-tail a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(34, 224, 214, 0.4);
  transition: border-color 160ms ease, color 160ms ease;
}

.page-about .eco-tail a:hover,
.page-about .eco-tail a:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

/* ---------- 响应式 ---------- */

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

  .page-about .team-row {
    grid-template-columns: 96px 176px minmax(0, 1fr);
    gap: 8px 22px;
  }

  .page-about .team-desc {
    grid-column: 3;
  }

  .page-about .eco-item {
    grid-template-columns: 216px minmax(0, 1fr);
    gap: 28px;
    align-items: start;
  }
}

@media (min-width: 900px) {
  .page-about .about-intro-grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 0.85fr);
    gap: clamp(36px, 5vw, 72px);
  }

  .page-about .range-grid {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  }

  .page-about .correction-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  }
}

@media (min-width: 1000px) {
  .page-about .versions-layout {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr);
    gap: clamp(32px, 4vw, 56px);
  }

  .page-about .versions-aside {
    position: sticky;
    top: 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-toc-list a,
  .page-about .paper-tag[data-ability]::after,
  .page-about .eco-tail a {
    transition: none;
  }
}