.page-about {
  --about-hairline: rgba(14, 47, 51, 0.14);
  --about-measure: 60ch;
  background-color: var(--c-sand);
  color: var(--c-teal);
  overflow-x: clip;
}

.page-about .about-crumb {
  padding-top: clamp(1.5rem, 4vw, 2.75rem);
  padding-bottom: 0.5rem;
}

.page-about .about-crumb a {
  color: var(--c-rock);
  text-decoration: none;
}

.page-about .about-crumb a:hover {
  color: var(--c-danxia);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(1.25rem, 3.5vw, 2.5rem) clamp(3rem, 8vw, 5.5rem);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 2;
  display: grid;
  gap: var(--space-3);
}

.page-about .about-hero__eyebrow {
  margin: 0;
  color: var(--c-danxia);
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--f-display);
  font-weight: 900;
  font-size: clamp(2.25rem, 8.4vw, 5.2rem);
  line-height: 1.04;
  letter-spacing: -0.015em;
  color: var(--c-night);
}

.page-about .about-hero__title-em {
  position: relative;
  color: var(--c-danxia);
}

.page-about .about-hero__title-em::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0.04em;
  height: 0.11em;
  background: var(--c-sandgold);
  opacity: 0.32;
}

.page-about .about-hero__body {
  display: grid;
  gap: var(--space-2);
  max-width: 54ch;
}

.page-about .about-hero__lead {
  margin: 0;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--c-teal);
}

.page-about .about-hero__text {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.95;
  color: var(--c-teal-72);
}

.page-about .about-index {
  margin-top: var(--space-1);
}

.page-about .about-index__list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 1.35rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-index__list a {
  display: inline-block;
  padding-bottom: 3px;
  border-bottom: 1px solid var(--c-turquoise);
  font-family: var(--f-mono);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--c-teal);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-soft), border-color var(--dur-fast) var(--ease-soft);
}

.page-about .about-index__list a:hover {
  color: var(--c-danxia);
  border-color: var(--c-danxia);
}

.page-about .about-hero__arc {
  position: absolute;
  right: -22%;
  bottom: -48%;
  z-index: 0;
  width: min(680px, 92vw);
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: radial-gradient(circle at 34% 30%, rgba(217, 164, 65, 0.3), rgba(163, 58, 43, 0.14) 48%, rgba(71, 58, 102, 0) 72%);
  pointer-events: none;
}

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

/* ---------- 章节底座 ---------- */

.page-about .about-section {
  position: relative;
  padding-block: var(--space-5);
}

.page-about .about-section h2 {
  margin: 0.45rem 0 0;
  font-family: var(--f-display);
  font-weight: 700;
  font-size: clamp(1.65rem, 4.2vw, 2.55rem);
  line-height: 1.2;
  letter-spacing: -0.005em;
  color: var(--c-night);
}

.page-about .about-section p {
  line-height: 1.9;
}

/* ---------- 沿革 ---------- */

.page-about .about-journey__head {
  display: grid;
  gap: 0.6rem;
  max-width: var(--about-measure);
}

.page-about .about-journey__lead {
  margin: 0;
  font-size: 1rem;
  color: var(--c-teal-72);
}

.page-about .about-journey__media {
  margin: var(--space-3) 0 var(--space-4);
  border-radius: var(--radius-l);
  overflow: hidden;
  background: var(--c-sand-deep);
}

.page-about .about-journey__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

.page-about .about-filter {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.25rem;
  padding-top: var(--space-3);
  border-top: 1px solid var(--about-hairline);
}

.page-about .about-filter__label {
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  color: var(--c-rock);
}

.page-about .about-filter__buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.page-about .about-chip {
  appearance: none;
  padding: 0.55rem 0.95rem;
  border: 1px solid var(--c-teal-28);
  border-radius: var(--radius-pill);
  background: transparent;
  color: var(--c-teal);
  font-family: var(--f-mono);
  font-size: 0.8rem;
  line-height: 1;
  cursor: pointer;
  transition: background-color var(--dur-fast) var(--ease-soft), color var(--dur-fast) var(--ease-soft), border-color var(--dur-fast) var(--ease-soft);
}

.page-about .about-chip:hover {
  border-color: var(--c-turquoise);
  color: var(--c-turquoise);
}

.page-about .about-chip.is-active,
.page-about .about-chip[aria-pressed="true"],
.page-about .about-chip[data-active="true"] {
  background-color: var(--c-paleturq);
  border-color: var(--c-turquoise);
  color: var(--c-teal);
  font-weight: 600;
}

.page-about .about-timeline {
  display: grid;
  gap: var(--space-4);
  margin: var(--space-4) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-mile {
  position: relative;
  display: grid;
  gap: 0.4rem;
  padding-left: 2.5rem;
}

.page-about .about-mile::before {
  content: "";
  position: absolute;
  left: 0.3rem;
  top: 0.7rem;
  width: 0.75rem;
  height: 0.75rem;
  border-radius: 50%;
  background: var(--c-sandgold);
  box-shadow: 0 0 0 5px rgba(217, 164, 65, 0.18);
}

.page-about .about-mile:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 0.67rem;
  top: 1.85rem;
  bottom: calc(-1 * var(--space-4));
  width: 1px;
  background: linear-gradient(to bottom, rgba(201, 107, 59, 0.55), rgba(201, 107, 59, 0));
}

.page-about .about-mile__year {
  font-family: var(--f-mono);
  font-size: 1.3rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: var(--c-danxia);
}

.page-about .about-mile__body h3 {
  margin: 0 0 0.35rem;
  font-family: var(--f-body);
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--c-night);
}

.page-about .about-mile__body p {
  margin: 0;
  max-width: 58ch;
  font-size: 0.9375rem;
  color: var(--c-teal-72);
}

.page-about .about-timeline [data-filter-item][data-hidden="true"] {
  display: none;
}

/* ---------- 服务原则 ---------- */

.page-about .about-rules__panel {
  display: grid;
  gap: var(--space-3);
  padding: clamp(1.5rem, 4.5vw, 3.25rem);
  border: 1px solid rgba(14, 47, 51, 0.08);
  border-radius: var(--radius-l);
  background: var(--c-sand-deep);
}

.page-about .about-rules__intro {
  display: grid;
  gap: 0.6rem;
  align-content: start;
}

.page-about .about-rules__lead {
  margin: 0;
  max-width: 40ch;
  font-size: 0.9375rem;
  color: var(--c-teal-72);
}

.page-about .about-rules__list {
  display: grid;
  gap: var(--space-3);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-rule {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0 1rem;
  padding-top: var(--space-3);
  border-top: 1px solid var(--about-hairline);
}

.page-about .about-rule:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .about-rule__num {
  padding-top: 0.2rem;
  font-family: var(--f-mono);
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  color: var(--c-terracotta);
}

.page-about .about-rule h3 {
  margin: 0 0 0.4rem;
  font-family: var(--f-display);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--c-night);
}

.page-about .about-rule p {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--c-teal-72);
}

/* ---------- 更新节奏 ---------- */

.page-about .about-section--dusk {
  background-color: var(--c-dusk);
  background-image: radial-gradient(circle at 10% 6%, rgba(217, 164, 65, 0.2), rgba(217, 164, 65, 0) 42%),
    radial-gradient(circle at 90% 94%, rgba(31, 166, 160, 0.2), rgba(31, 166, 160, 0) 46%);
  color: var(--c-sand);
}

.page-about .about-section--dusk h2 {
  color: var(--c-sand);
}

.page-about .about-cadence__eyebrow {
  color: var(--c-sandgold);
}

.page-about .about-cadence__lead {
  margin: 1rem 0 0;
  max-width: 56ch;
  font-size: 1rem;
  color: var(--c-sand-72);
}

.page-about .about-cadence__stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));
  gap: 1.75rem 1rem;
  margin: var(--space-4) 0 0;
  padding-top: var(--space-3);
  border-top: 1px solid var(--c-sand-16);
}

.page-about .about-cadence__stat dt {
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  color: var(--c-sand-54);
}

.page-about .about-cadence__stat dd {
  margin: 0.45rem 0 0;
  font-family: var(--f-mono);
  font-size: clamp(1.3rem, 3.4vw, 1.85rem);
  font-weight: 600;
  color: var(--c-sandgold);
}

.page-about .about-cadence__foot {
  margin: var(--space-4) 0 var(--space-3);
  max-width: 58ch;
  font-size: 0.9375rem;
  color: var(--c-sand-72);
}

/* ---------- 团队与支持 ---------- */

.page-about .about-team__grid {
  display: grid;
  gap: var(--space-3);
}

.page-about .about-team__text {
  display: grid;
  gap: 0.7rem;
  align-content: start;
}

.page-about .about-team__lead {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--c-teal-72);
}

.page-about .about-team__roles {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.9rem 1.25rem;
  margin: var(--space-2) 0;
  padding: 0;
  list-style: none;
}

.page-about .about-team__roles li {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  padding-bottom: 0.7rem;
  border-bottom: 1px solid var(--about-hairline);
}

.page-about .about-team__num {
  font-family: var(--f-mono);
  font-size: 1.45rem;
  font-weight: 600;
  color: var(--c-danxia);
}

.page-about .about-team__role {
  font-size: 0.9rem;
  color: var(--c-teal-72);
}

.page-about .about-team__note {
  margin: 0;
  max-width: 46ch;
  font-size: 0.9rem;
  color: var(--c-rock);
}

.page-about .about-team__action {
  margin: 0.4rem 0 0;
}

.page-about .about-team__media {
  margin: 0;
  border-radius: var(--radius-l);
  overflow: hidden;
  background: var(--c-sand-deep);
}

.page-about .about-team__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

/* ---------- 覆盖与生态 ---------- */

.page-about .about-reach__head {
  display: grid;
  gap: 0.7rem;
  max-width: 62ch;
}

.page-about .about-reach__lead {
  margin: 0;
  font-size: 1rem;
  color: var(--c-teal-72);
}

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

.page-about .about-reach__map {
  margin: 0;
  border-radius: var(--radius-m);
  overflow: hidden;
  background-color: var(--c-teal);
}

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

.page-about .about-reach__notes {
  display: grid;
  gap: var(--space-3);
  align-content: start;
}

.page-about .about-reach__note {
  padding-left: 1.1rem;
  border-left: 2px solid var(--c-sandgold);
}

.page-about .about-reach__note:nth-child(2) {
  border-left-color: var(--c-turquoise);
}

.page-about .about-reach__note:nth-child(3) {
  border-left-color: var(--c-terracotta);
}

.page-about .about-reach__note h3 {
  margin: 0 0 0.35rem;
  font-family: var(--f-display);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--c-night);
}

.page-about .about-reach__note p {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--c-teal-72);
}

/* ---------- 去向 ---------- */

.page-about .about-next {
  padding-bottom: var(--space-6);
}

.page-about .about-next__inner {
  display: grid;
  gap: var(--space-3);
}

.page-about .about-next__links {
  display: grid;
  gap: 0.75rem;
}

.page-about .about-next__card {
  display: grid;
  gap: 0.5rem;
  padding: 1.4rem 1.35rem;
  border: 1px solid var(--about-hairline);
  border-radius: var(--radius-m);
  background: var(--c-sand);
  text-decoration: none;
  transition: border-color var(--dur-fast) var(--ease-soft), background-color var(--dur-fast) var(--ease-soft), transform var(--dur-fast) var(--ease-soft);
}

.page-about .about-next__card:hover {
  border-color: var(--c-turquoise);
  background-color: var(--c-paleturq);
  transform: translateY(-2px);
}

.page-about .about-next__label {
  font-family: var(--f-display);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--c-night);
}

.page-about .about-next__desc {
  font-size: 0.875rem;
  line-height: 1.75;
  color: var(--c-teal-72);
}

/* ---------- 响应式 ---------- */

@media (min-width: 768px) {
  .page-about .about-mile {
    grid-template-columns: 7.5rem minmax(0, 1fr);
    column-gap: 1.75rem;
    padding-left: 3.25rem;
    align-items: start;
  }

  .page-about .about-mile__year {
    padding-top: 0.1rem;
    font-size: 1.5rem;
    text-align: right;
  }

  .page-about .about-mile::before {
    left: 0.55rem;
  }

  .page-about .about-mile:not(:last-child)::after {
    left: 0.92rem;
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    grid-template-areas:
      "eyebrow eyebrow"
      "title   body";
    align-items: end;
    column-gap: clamp(2.5rem, 6vw, 6rem);
    row-gap: clamp(1.25rem, 3vw, 2.25rem);
  }

  .page-about .about-hero__eyebrow {
    grid-area: eyebrow;
  }

  .page-about .about-hero__title {
    grid-area: title;
  }

  .page-about .about-hero__body {
    grid-area: body;
    padding-bottom: 0.75rem;
  }

  .page-about .about-rules__panel {
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
    gap: clamp(2rem, 5vw, 4.5rem);
    align-items: start;
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.9fr);
    gap: clamp(2rem, 6vw, 5rem);
    align-items: center;
  }

  .page-about .about-reach__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    gap: clamp(2rem, 5vw, 4rem);
    align-items: start;
  }

  .page-about .about-cadence__lead {
    max-width: 52ch;
  }
}

@media (min-width: 1180px) {
  .page-about .about-hero__vertical {
    display: block;
    position: absolute;
    top: clamp(3rem, 7vw, 5.5rem);
    right: clamp(0.5rem, 1.6vw, 1.25rem);
    z-index: 3;
    writing-mode: vertical-rl;
    font-family: var(--f-mono);
    font-size: 0.7rem;
    letter-spacing: 0.42em;
    color: var(--c-rock);
    opacity: 0.75;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-chip,
  .page-about .about-next__card,
  .page-about .about-index__list a {
    transition: none;
  }

  .page-about .about-next__card:hover {
    transform: none;
  }
}