.page-about {
  --about-edge: 20px;
}

/* ---------- 通用排版微调 ---------- */
.page-about .h-display {
  overflow-wrap: break-word;
  word-break: break-word;
}

.page-about .about-hero__main .lead,
.page-about .about-rule__head .lead,
.page-about .about-scope__head .lead {
  color: var(--dust);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-block: 28px 0;
  background:
    radial-gradient(circle at 82% 6%, rgba(240, 190, 76, 0.09), transparent 46%),
    radial-gradient(circle at 12% 40%, rgba(99, 210, 227, 0.07), transparent 52%);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 34px;
}

.page-about .about-hero__main .breadcrumbs {
  margin-bottom: 26px;
}

.page-about .about-hero__main .eyebrow {
  margin: 0 0 14px;
}

.page-about .about-hero__main .h-display {
  margin: 0 0 22px;
  max-width: 17ch;
}

.page-about .about-hero__main .lead {
  margin: 0;
  max-width: 54ch;
}

.page-about .about-hero__aside {
  border-left: 2px solid var(--gold);
  padding-left: 18px;
  display: grid;
  gap: 16px;
}

.page-about .about-hero__aside .rotate-note {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

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

.page-about .about-facts li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-size: 13px;
  color: var(--dust);
}

.page-about .about-facts .text-mono {
  font-size: 19px;
  font-weight: 700;
  color: var(--gold);
  letter-spacing: 0.02em;
}

.page-about .about-hero__figure {
  margin-top: 46px;
}

/* ---------- 起点 ---------- */
.page-about .about-why__grid {
  display: grid;
  gap: 38px;
}

.page-about .about-why__lead::before {
  content: "";
  display: block;
  width: 120px;
  height: 2px;
  margin-bottom: 34px;
  background: linear-gradient(90deg, var(--gold), rgba(240, 190, 76, 0));
  transform: rotate(-6deg);
  transform-origin: left center;
}

.page-about .about-why__lead .eyebrow {
  margin: 0 0 14px;
}

.page-about .about-why__lead .h-section {
  margin: 0 0 20px;
}

.page-about .about-why__lead p {
  margin: 0;
  color: var(--dust);
  font-size: 15px;
  line-height: 1.85;
}

.page-about .about-why__lead p + p {
  margin-top: 18px;
}

.page-about .about-why__side {
  align-self: end;
  padding: 22px 20px;
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 0 100%);
}

.page-about .about-why__side .h-sub {
  margin: 0 0 16px;
  color: var(--moon);
}

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

.page-about .about-why__list li {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--dust);
}

.page-about .about-why__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.7em;
  width: 11px;
  height: 1px;
  background: var(--stoppage);
}

/* ---------- 口径与四条主线 ---------- */
.page-about .about-rule {
  position: relative;
  overflow: hidden;
}

.page-about .about-rule::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(118deg, rgba(240, 190, 76, 0.07), transparent 44%);
}

.page-about .about-rule .container {
  position: relative;
}

.page-about .about-rule__head {
  max-width: 62ch;
}

.page-about .about-rule__head .eyebrow {
  margin: 0 0 14px;
}

.page-about .about-rule__head .h-section {
  margin: 0 0 18px;
}

.page-about .about-rule__head .lead {
  margin: 0;
}

.page-about .rule-grid {
  display: grid;
  gap: 18px;
  margin-top: 42px;
}

.page-about .rule-card {
  position: relative;
  padding: 22px 20px 20px;
  background: var(--ink-night);
  border: 1px solid var(--line);
  border-top: 2px solid var(--gold);
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 0 100%);
  transition: border-color 0.3s var(--ease), transform 0.3s var(--ease);
}

.page-about .rule-card:hover,
.page-about .rule-card:focus-visible {
  border-color: var(--gold-line);
  transform: translateY(-3px);
  outline: none;
}

.page-about .rule-card__index {
  display: block;
  margin-bottom: 10px;
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--cyan);
}

.page-about .rule-card__title {
  margin: 0 0 14px;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.03em;
  color: var(--moon);
}

.page-about .rule-card__fields {
  list-style: none;
  margin: 0 0 16px;
  padding: 0;
  display: grid;
  gap: 7px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--dust);
}

.page-about .rule-card__fields li {
  position: relative;
  padding-left: 12px;
}

.page-about .rule-card__fields li::before {
  content: "·";
  position: absolute;
  left: 0;
  color: var(--gold);
}

.page-about .rule-card__detail {
  border-top: 1px solid var(--line);
  padding-top: 12px;
}

.page-about .rule-card__detail summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  list-style: none;
  cursor: pointer;
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--cyan);
}

.page-about .rule-card__detail summary::-webkit-details-marker {
  display: none;
}

.page-about .rule-card__detail summary::after {
  content: "＋";
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--gold);
}

.page-about .rule-card__detail[open] summary::after {
  content: "－";
}

.page-about .rule-card__detail p {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--dust);
}

/* ---------- 三块内容的分工 ---------- */
.page-about .about-scope__head {
  max-width: 60ch;
}

.page-about .about-scope__head .eyebrow {
  margin: 0 0 14px;
}

.page-about .about-scope__head .h-section {
  margin: 0 0 18px;
}

.page-about .about-scope__head .lead {
  margin: 0;
}

.page-about .track {
  margin-top: 38px;
  border-bottom: 1px solid var(--line);
}

.page-about .track__row {
  position: relative;
  display: grid;
  gap: 12px;
  padding-block: 26px;
  border-top: 1px solid var(--line);
}

.page-about .track__row::before {
  content: "";
  position: absolute;
  left: 0;
  top: -1px;
  width: 0;
  height: 1px;
  background: var(--gold);
  transition: width 0.45s var(--ease);
}

.page-about .track__row:hover::before,
.page-about .track__row:focus-within::before {
  width: 100%;
}

.page-about .track__index {
  display: block;
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--cyan);
}

.page-about .track__name .h-sub {
  margin: 8px 0 0;
  color: var(--moon);
}

.page-about .track__desc {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--dust);
}

.page-about .track__meta {
  margin: 0;
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--gold);
}

/* ---------- 站务流程 ---------- */
.page-about .about-desk__grid {
  display: grid;
  gap: 40px;
}

.page-about .about-desk__body .eyebrow {
  margin: 0 0 14px;
}

.page-about .about-desk__body .h-section {
  margin: 0 0 18px;
}

.page-about .about-desk__body > p {
  margin: 0;
  max-width: 52ch;
  color: var(--dust);
  font-size: 15px;
  line-height: 1.85;
}

.page-about .flow {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  gap: 22px;
}

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

.page-about .flow__step::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 20px;
  bottom: -22px;
  width: 1px;
  background: repeating-linear-gradient(180deg, var(--gold-line) 0 6px, transparent 6px 12px);
}

.page-about .flow__step:last-child::before {
  display: none;
}

.page-about .flow__dot {
  position: absolute;
  left: 0;
  top: 4px;
  width: 19px;
  height: 19px;
  background: var(--ink-void);
  border: 1px solid var(--gold);
  transform: rotate(45deg);
}

.page-about .flow__step .h-sub {
  margin: 0 0 8px;
  color: var(--moon);
}

.page-about .flow__step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--dust);
}

.page-about .about-desk__note {
  margin: 28px 0 0;
  padding: 15px 16px;
  border-left: 2px solid var(--cyan);
  background: rgba(99, 210, 227, 0.06);
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--dust);
}

.page-about .about-desk__figure {
  margin: 0;
}

/* ---------- 边界 ---------- */
.page-about .about-not__band {
  margin-bottom: 42px;
}

.page-about .about-not__band .figure__frame {
  border-top: 1px solid var(--gold-line);
  border-bottom: 1px solid var(--line);
}

.page-about .about-not__body {
  max-width: 760px;
}

.page-about .about-not__body .eyebrow {
  margin: 0 0 14px;
}

.page-about .about-not__body .h-section {
  margin: 0 0 8px;
}

.page-about .about-not__list {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-not__list li {
  position: relative;
  padding: 0 0 16px 22px;
  border-bottom: 1px solid var(--line);
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--dust);
}

.page-about .about-not__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.74em;
  width: 12px;
  height: 2px;
  background: var(--stoppage);
  transform: rotate(-12deg);
}

.page-about .about-not__list strong {
  color: var(--moon);
  font-weight: 600;
}

.page-about .about-not__more {
  margin: 26px 0 0;
}

/* ---------- 阅读路线 ---------- */
.page-about .about-route__head {
  max-width: 56ch;
}

.page-about .about-route__head .eyebrow {
  margin: 0 0 14px;
}

.page-about .about-route__head .h-section {
  margin: 0;
}

.page-about .route-list {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .route-list__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 18px;
  padding: 22px 20px;
  background: linear-gradient(135deg, rgba(20, 40, 74, 0.9), rgba(13, 26, 50, 0.55));
  border-left: 2px solid var(--gold);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .route-list__no {
  font-size: 22px;
  line-height: 1;
  color: var(--gold);
}

.page-about .route-list__item .h-sub {
  margin: 0 0 8px;
  color: var(--moon);
}

.page-about .route-list__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--dust);
}

.page-about .route-list__item a,
.page-about .about-route__foot a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(99, 210, 227, 0.4);
}

.page-about .route-list__item a:hover,
.page-about .route-list__item a:focus-visible,
.page-about .about-route__foot a:hover,
.page-about .about-route__foot a:focus-visible {
  color: var(--gold-soft);
  border-bottom-color: var(--gold-line);
}

.page-about .about-route__foot {
  margin: 30px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--dust);
}

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

  .page-about .flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }

  .page-about .flow__step {
    padding-left: 0;
    padding-top: 40px;
  }

  .page-about .flow__step::before {
    left: 24px;
    right: -26px;
    top: 9px;
    bottom: auto;
    width: auto;
    height: 1px;
    background: repeating-linear-gradient(90deg, var(--gold-line) 0 6px, transparent 6px 12px);
  }

  .page-about .flow__dot {
    left: 0;
    top: 0;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 960px) {
  .page-about .about-hero {
    padding-block: 44px 0;
  }

  .page-about .about-hero__grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    align-items: end;
  }

  .page-about .about-hero__main {
    grid-column: 1 / span 8;
  }

  .page-about .about-hero__aside {
    grid-column: 10 / span 3;
  }

  .page-about .about-hero__aside .rotate-note {
    writing-mode: vertical-rl;
    letter-spacing: 0.22em;
  }

  .page-about .about-hero__figure {
    margin-top: 84px;
  }

  .page-about .about-why__grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    align-items: end;
  }

  .page-about .about-why__lead {
    grid-column: 1 / span 7;
  }

  .page-about .about-why__side {
    grid-column: 9 / span 4;
  }

  .page-about .about-desk__grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    align-items: start;
  }

  .page-about .about-desk__body {
    grid-column: 1 / span 7;
  }

  .page-about .about-desk__figure {
    grid-column: 9 / span 4;
    margin-top: 16px;
  }

  .page-about .track__row {
    grid-template-columns: minmax(0, 3fr) minmax(0, 6fr) minmax(0, 3fr);
    gap: 28px;
    align-items: start;
    padding-block: 30px;
  }

  .page-about .track__meta {
    text-align: right;
    padding-top: 4px;
  }

  .page-about .route-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }

  .page-about .about-not__band {
    margin-bottom: 56px;
  }
}

@media (min-width: 1100px) {
  .page-about .rule-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    align-items: start;
    gap: 20px;
  }

  .page-about .rule-card:nth-child(2) {
    margin-top: 40px;
  }

  .page-about .rule-card:nth-child(3) {
    margin-top: 12px;
  }

  .page-about .rule-card:nth-child(4) {
    margin-top: 52px;
  }
}

/* ---------- 动效收敛 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .rule-card,
  .page-about .track__row::before {
    transition: none;
  }

  .page-about .rule-card:hover,
  .page-about .rule-card:focus-visible {
    transform: none;
  }
}