.page-about {
  --about-gap: clamp(3rem, 8vw, 6.5rem);
  background: var(--ink-900);
  color: var(--warm);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about .about-hero {
  position: relative;
  padding-block: var(--sp-3) var(--sp-4);
  background:
    radial-gradient(115% 90% at 88% -10%, rgba(37, 227, 208, 0.16), transparent 62%),
    radial-gradient(85% 75% at 6% 108%, rgba(255, 106, 26, 0.14), transparent 66%),
    var(--ink-900);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero__grid {
  display: grid;
  gap: var(--sp-4);
  margin-top: var(--sp-4);
}

.page-about .about-hero h1 {
  margin: var(--sp-2) 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.2rem, 7.2vw, 4.6rem);
  line-height: 1.04;
  letter-spacing: -0.01em;
  color: var(--warm);
  max-width: 18ch;
}

.page-about .about-hero .lede {
  margin-top: var(--sp-3);
  max-width: 46ch;
  color: var(--mist);
  font-size: clamp(1rem, 1.6vw, 1.1rem);
  line-height: 1.85;
}

.page-about .about-hero__aside {
  position: relative;
  padding: var(--sp-3) var(--sp-3) var(--sp-3) var(--sp-3);
  background: linear-gradient(160deg, rgba(12, 42, 34, 0.95), rgba(6, 27, 22, 0.6));
  border: 1px solid var(--line);
  border-left: 3px solid var(--cyan);
}

.page-about .about-hero__cap {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-hero__ruler {
  position: relative;
  height: 46px;
  margin: var(--sp-2) 0 var(--sp-3);
  background-image: repeating-linear-gradient(
    to right,
    var(--line-strong) 0 1px,
    transparent 1px 11.5px
  );
  background-position: left bottom;
  background-size: 100% 26px;
  background-repeat: no-repeat;
  border-bottom: 1px solid var(--line-strong);
}

.page-about .about-hero__ruler-fill {
  position: absolute;
  left: 0;
  bottom: -1px;
  height: 2px;
  width: 100%;
  background: linear-gradient(90deg, var(--orange), var(--cyan));
}

.page-about .about-hero__stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--sp-2);
}

.page-about .about-hero__stats li {
  display: grid;
  grid-template-columns: auto auto 1fr;
  align-items: baseline;
  gap: 0.35rem;
  padding-bottom: var(--sp-2);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero__stats li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-hero__num {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--orange);
  line-height: 1;
}

.page-about .about-hero__unit {
  font-size: 0.8rem;
  color: var(--mist);
}

.page-about .about-hero__desc {
  font-size: 0.8rem;
  line-height: 1.5;
  color: var(--mist);
}

.page-about .about-hero__toc {
  display: grid;
  gap: 0;
  margin-top: var(--sp-4);
  border-top: 1px solid var(--line);
}

.page-about .about-hero__toc a {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  padding: 0.75rem 0.25rem;
  border-bottom: 1px solid var(--line);
  color: var(--mist);
  font-size: 0.9rem;
  text-decoration: none;
  transition: color 200ms var(--ease), background-color 200ms var(--ease);
}

.page-about .about-hero__toc a span {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--cyan);
  letter-spacing: 0.1em;
}

.page-about .about-hero__toc a:hover,
.page-about .about-hero__toc a:focus-visible {
  color: var(--warm);
  background: rgba(37, 227, 208, 0.08);
}

.page-about .about-section {
  padding-block: var(--about-gap);
  border-bottom: 1px solid var(--line);
}

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

.page-about .about-head__title {
  margin: var(--sp-2) 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.7rem, 4.4vw, 2.9rem);
  line-height: 1.12;
  letter-spacing: -0.005em;
  color: var(--warm);
}

.page-about .about-head__intro {
  margin-top: var(--sp-2);
  color: var(--mist);
  font-size: 1rem;
  line-height: 1.85;
}

/* 01 起点 */
.page-about .about-origin__body {
  margin-top: var(--sp-3);
  display: grid;
  gap: var(--sp-3);
  max-width: 70ch;
}

.page-about .about-origin__body p {
  margin: 0;
  color: var(--mist);
  font-size: 1rem;
  line-height: 1.9;
}

.page-about .about-origin__body p:first-child {
  color: var(--warm);
  font-size: 1.06rem;
}

.page-about .about-origin__quote {
  margin: var(--sp-4) 0 0;
  padding: var(--sp-3) 0 var(--sp-3) var(--sp-3);
  border-left: 3px solid var(--orange);
  background: linear-gradient(90deg, rgba(255, 106, 26, 0.09), transparent 70%);
}

.page-about .about-origin__quote p {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.15rem, 2.6vw, 1.6rem);
  line-height: 1.5;
  color: var(--warm);
}

/* 02 编年 */
.page-about .about-section--chronicle {
  background: var(--ink-800);
}

.page-about .chronicle {
  margin-top: var(--sp-4);
  display: grid;
  gap: var(--sp-4);
}

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .timeline__item {
  position: relative;
  margin-left: 0.35rem;
  padding-left: 1.6rem;
  padding-bottom: var(--sp-3);
  border-left: 1px solid var(--line-strong);
}

.page-about .timeline__item:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -0.34rem;
  top: 0.5rem;
  width: 0.62rem;
  height: 0.62rem;
  background: var(--ink-800);
  border: 1px solid var(--cyan);
}

.page-about .timeline__summary {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  list-style: none;
  cursor: pointer;
  padding: 0.15rem 0;
}

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

.page-about .timeline__summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1rem;
  line-height: 1;
  color: var(--orange);
  margin-left: auto;
}

.page-about .timeline__node[open] > .timeline__summary::after {
  content: "\2212";
}

.page-about .timeline__summary:hover .timeline__label,
.page-about .timeline__summary:focus-visible .timeline__label {
  color: var(--cyan);
}

.page-about .timeline__no {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--orange);
}

.page-about .timeline__label {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--warm);
  transition: color 200ms var(--ease);
}

.page-about .timeline__body {
  padding-top: 0.6rem;
  border-top: 1px dashed var(--line);
  margin-top: 0.5rem;
}

.page-about .timeline__body p {
  margin: 0;
  color: var(--mist);
  font-size: 0.92rem;
  line-height: 1.8;
}

.page-about .chronicle__media {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--ink-900);
}

.page-about .chronicle__media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 3 / 2;
}

.page-about .chronicle__media figcaption {
  padding: var(--sp-2);
  font-size: 0.8rem;
  line-height: 1.6;
  color: var(--mist);
  border-top: 1px solid var(--line);
}

/* 03 流程（浅色区） */
.page-about .about-section--light {
  --line: rgba(6, 27, 22, 0.16);
  --line-strong: rgba(6, 27, 22, 0.34);
  background: var(--warm);
  color: var(--ink-900);
  border-bottom-color: rgba(6, 27, 22, 0.14);
}

.page-about .about-section--light .about-head__title {
  color: var(--ink-900);
}

.page-about .about-section--light .about-head__intro {
  color: #3d5349;
}

.page-about .about-section--light .eyebrow {
  color: #2a6f5d;
}

.page-about .flow {
  margin-top: var(--sp-4);
}

.page-about .flow__radio {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.page-about .flow__tabs {
  display: grid;
  gap: 0.5rem;
}

.page-about .flow__tab {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 0.7rem 0.9rem;
  cursor: pointer;
  background: rgba(6, 27, 22, 0.05);
  border: 1px solid var(--line-strong);
  transition: background-color 200ms var(--ease), color 200ms var(--ease),
    border-color 200ms var(--ease);
}

.page-about .flow__tab-time {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: #2a6f5d;
}

.page-about .flow__tab-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--ink-900);
}

.page-about #flow-pre:checked ~ .flow__tabs label[for="flow-pre"],
.page-about #flow-live:checked ~ .flow__tabs label[for="flow-live"],
.page-about #flow-post:checked ~ .flow__tabs label[for="flow-post"] {
  background: var(--ink-900);
  border-color: var(--ink-900);
}

.page-about #flow-pre:checked ~ .flow__tabs label[for="flow-pre"] .flow__tab-name,
.page-about #flow-live:checked ~ .flow__tabs label[for="flow-live"] .flow__tab-name,
.page-about #flow-post:checked ~ .flow__tabs label[for="flow-post"] .flow__tab-name {
  color: var(--warm);
}

.page-about #flow-pre:checked ~ .flow__tabs label[for="flow-pre"] .flow__tab-time,
.page-about #flow-live:checked ~ .flow__tabs label[for="flow-live"] .flow__tab-time,
.page-about #flow-post:checked ~ .flow__tabs label[for="flow-post"] .flow__tab-time {
  color: var(--cyan);
}

.page-about .flow__tab:hover {
  border-color: var(--orange);
}

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

.page-about #flow-pre:checked ~ .flow__panels #flow-panel-pre,
.page-about #flow-live:checked ~ .flow__panels #flow-panel-live,
.page-about #flow-post:checked ~ .flow__panels #flow-panel-post {
  display: block;
}

.page-about .flow__panels {
  margin-top: var(--sp-3);
}

.page-about .flow__panel {
  padding-top: var(--sp-3);
  border-top: 2px solid var(--orange);
}

.page-about .flow__panel-text h3 {
  margin: 0 0 var(--sp-2);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.25rem, 3vw, 1.7rem);
  line-height: 1.2;
  color: var(--ink-900);
}

.page-about .flow__panel-text p {
  margin: 0;
  color: #34524a;
  font-size: 1rem;
  line-height: 1.85;
}

.page-about .flow__list {
  list-style: none;
  margin: var(--sp-2) 0 0;
  padding: 0;
  display: grid;
  gap: 0.45rem;
}

.page-about .flow__list li {
  position: relative;
  padding-left: 1.1rem;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--ink-900);
}

.page-about .flow__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 0.5rem;
  height: 1px;
  background: var(--orange);
}

.page-about .flow__media {
  margin: var(--sp-3) 0 0;
}

.page-about .flow__media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 3 / 2;
  border: 1px solid var(--line-strong);
}

/* 04 团队 */
.page-about .crew {
  margin-top: var(--sp-4);
  display: grid;
  gap: var(--sp-3);
}

.page-about .crew__card {
  position: relative;
  padding: var(--sp-3) var(--sp-3) var(--sp-3) var(--sp-3);
  background: var(--ink-800);
  border: 1px solid var(--line);
  transition: border-color 220ms var(--ease), transform 220ms var(--ease);
}

.page-about .crew__card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 46px;
  height: 3px;
  background: linear-gradient(90deg, var(--red) 0 50%, var(--blue) 50% 100%);
}

.page-about .crew__card:hover,
.page-about .crew__card:focus-within {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

.page-about .crew__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .crew__title {
  margin: 0.4rem 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--warm);
}

.page-about .crew__num {
  margin: 0.25rem 0 0;
  font-family: var(--font-mono);
  font-size: 2.4rem;
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
}

.page-about .crew__num span {
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--mist);
  margin-left: 0.25rem;
}

.page-about .crew__text {
  margin: var(--sp-2) 0 0;
  color: var(--mist);
  font-size: 0.92rem;
  line-height: 1.8;
}

.page-about .crew__tags {
  list-style: none;
  margin: var(--sp-2) 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.page-about .crew__tags li {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  padding: 0.2rem 0.5rem;
  color: var(--cyan);
  border: 1px solid rgba(37, 227, 208, 0.4);
}

.page-about .crew__partners {
  margin: var(--sp-4) 0 0;
  display: grid;
  gap: var(--sp-3);
  border-top: 1px solid var(--line-strong);
  padding-top: var(--sp-3);
}

.page-about .crew__partner dt {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--mist);
}

.page-about .crew__partner dd {
  margin: 0.35rem 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.9rem;
  line-height: 1;
  color: var(--warm);
}

.page-about .crew__partner dd span {
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--mist);
  margin-left: 0.25rem;
}

.page-about .crew__partner p {
  margin: 0.5rem 0 0;
  color: var(--mist);
  font-size: 0.85rem;
  line-height: 1.7;
}

/* 05 城市 */
.page-about .about-section--city {
  background:
    radial-gradient(70% 60% at 100% 0%, rgba(138, 107, 255, 0.12), transparent 65%),
    var(--ink-900);
}

.page-about .city__media {
  margin: var(--sp-4) 0 0;
  border: 1px solid var(--line);
}

.page-about .city__media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 16 / 9;
}

.page-about .city__media figcaption {
  padding: var(--sp-2);
  border-top: 1px solid var(--line);
  font-size: 0.8rem;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .city__grid {
  margin-top: var(--sp-4);
  display: grid;
  gap: var(--sp-3);
}

.page-about .city__item {
  padding-top: var(--sp-2);
  border-top: 1px solid var(--line-strong);
}

.page-about .city__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  color: var(--violet);
}

.page-about .city__item h3 {
  margin: 0.4rem 0 0.5rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--warm);
}

.page-about .city__item p {
  margin: 0;
  color: var(--mist);
  font-size: 0.92rem;
  line-height: 1.8;
}

.page-about .city__note {
  margin: var(--sp-3) 0 0;
  padding: var(--sp-2) var(--sp-3);
  border-left: 2px solid var(--cyan);
  background: rgba(37, 227, 208, 0.07);
  color: var(--mist);
  font-size: 0.92rem;
  line-height: 1.8;
}

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

/* 06 订阅 */
.page-about .pass {
  margin-top: var(--sp-4);
  display: grid;
  gap: var(--sp-3);
}

.page-about .pass__item {
  position: relative;
  padding: var(--sp-3);
  background: var(--paper);
  border: 1px solid rgba(6, 27, 22, 0.2);
  border-left: 2px dashed rgba(6, 27, 22, 0.45);
}

.page-about .pass__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: #8a4520;
}

.page-about .pass__item h3 {
  margin: 0.45rem 0 0.6rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.2rem;
  line-height: 1.25;
  color: var(--ink-900);
}

.page-about .pass__item p {
  margin: 0;
  color: #34524a;
  font-size: 0.92rem;
  line-height: 1.8;
}

.page-about .service__more {
  margin: var(--sp-3) 0 0;
  font-size: 0.92rem;
  line-height: 1.8;
  color: #34524a;
}

.page-about .service__more a,
.page-about .pass__item a {
  color: #1c4f8f;
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* 收尾 */
.page-about .about-cta {
  padding-block: var(--about-gap);
  background:
    linear-gradient(120deg, rgba(255, 106, 26, 0.16), transparent 55%),
    var(--ink-800);
  border-top: 3px solid var(--orange);
}

.page-about .about-cta__text h2 {
  margin: var(--sp-2) 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.7rem, 4.6vw, 2.8rem);
  line-height: 1.1;
  color: var(--warm);
}

.page-about .about-cta__text p {
  margin: var(--sp-2) 0 0;
  max-width: 44ch;
  color: var(--mist);
  font-size: 1rem;
  line-height: 1.8;
}

.page-about .about-cta__actions {
  margin-top: var(--sp-3);
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

@media (min-width: 700px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--sp-3);
  }

  .page-about .about-hero__stats li {
    grid-template-columns: auto 1fr;
    grid-template-areas:
      "num unit"
      "desc desc";
    align-items: end;
    padding-bottom: 0;
    border-bottom: 0;
    border-left: 1px solid var(--line);
    padding-left: var(--sp-2);
  }

  .page-about .about-hero__num {
    grid-area: num;
  }

  .page-about .about-hero__unit {
    grid-area: unit;
    justify-self: start;
    padding-bottom: 0.2rem;
  }

  .page-about .about-hero__desc {
    grid-area: desc;
    margin-top: 0.35rem;
  }

  .page-about .about-hero__toc {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: var(--sp-3);
  }

  .page-about .about-origin__body {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: var(--sp-4);
  }

  .page-about .about-origin__body p:first-child {
    grid-column: 1 / -1;
  }

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

  .page-about .flow__panel {
    display: none;
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    gap: var(--sp-3);
    align-items: start;
  }

  .page-about .flow__media {
    margin-top: 0;
  }

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

  .page-about .crew__partners {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--sp-4);
  }

  .page-about .city__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--sp-4);
  }

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

  .page-about .about-cta__inner {
    display: grid;
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
    gap: var(--sp-4);
    align-items: end;
  }

  .page-about .about-cta__actions {
    margin-top: 0;
    justify-content: flex-end;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: var(--sp-5);
    align-items: start;
  }

  .page-about .about-hero__aside {
    margin-top: 0.75rem;
  }

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

  .page-about .chronicle {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: var(--sp-4);
    align-items: start;
  }

  .page-about .timeline {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    column-gap: var(--sp-2);
  }

  .page-about .timeline__item {
    margin-left: 0;
    padding-left: 0;
    padding-bottom: 0;
    padding-top: 1.5rem;
    border-left: 0;
    border-top: 1px solid var(--line-strong);
  }

  .page-about .timeline__item::before {
    left: 0;
    top: -0.3rem;
  }

  .page-about .timeline__summary {
    flex-wrap: wrap;
    gap: 0.3rem;
  }

  .page-about .timeline__summary::after {
    margin-left: 0;
    width: 100%;
    text-align: right;
  }

  .page-about .chronicle__media {
    margin-top: 0;
  }

  .page-about .crew {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--sp-2);
  }

  .page-about .crew__card:nth-child(2) {
    margin-top: var(--sp-4);
  }

  .page-about .pass {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: var(--sp-2);
  }

  .page-about .pass__item:nth-child(even) {
    margin-top: var(--sp-3);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .crew__card,
  .page-about .timeline__label,
  .page-about .about-hero__toc a,
  .page-about .flow__tab {
    transition: none;
  }

  .page-about .crew__card:hover,
  .page-about .crew__card:focus-within {
    transform: none;
  }
}