.page-about {
  --about-gap: clamp(2.6rem, 6vw, 4.6rem);
  background: var(--c-purple);
  color: var(--c-white);
  padding-bottom: clamp(3rem, 8vw, 6rem);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(2.4rem, 7vw, 5rem) 0 clamp(2.2rem, 5vw, 3.6rem);
  isolation: isolate;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  z-index: -1;
  top: -8%;
  right: 0;
  width: min(48%, 560px);
  height: 112%;
  background: linear-gradient(142deg, rgba(201, 162, 75, .16), rgba(201, 162, 75, 0) 66%);
  clip-path: polygon(24% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  display: grid;
  gap: 2.4rem;
  align-items: end;
}

.page-about .about-hero__title {
  margin: 1rem 0 1.1rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2.2rem, 6.6vw, 4.2rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--c-white);
}

.page-about .about-hero__lede {
  max-width: 44ch;
  margin: 0 0 1.8rem;
  font-size: clamp(1rem, 1.6vw, 1.12rem);
  line-height: 1.85;
  color: var(--c-grey);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .8rem;
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--rad);
  overflow: hidden;
}

.page-about .about-fact {
  background: var(--c-panel);
  padding: 1.05rem 1rem 1.15rem;
}

.page-about .about-fact dt {
  font-size: .72rem;
  letter-spacing: .14em;
  color: var(--c-grey);
}

.page-about .about-fact dd {
  margin: .55rem 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.18rem;
  letter-spacing: -0.01em;
  color: var(--c-gold-lite);
}

/* ---------- 主体两栏 ---------- */
.page-about .about-layout {
  display: grid;
  gap: 2.2rem;
  padding-top: clamp(2.4rem, 6vw, 4rem);
  border-top: 1px solid var(--c-line);
}

.page-about .about-rail__label {
  margin: 0 0 .9rem;
  font-size: .74rem;
  letter-spacing: .22em;
  color: var(--c-gold);
}

.page-about .rail-list {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem .9rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .rail-list__link {
  display: block;
  padding: .2rem 0;
  font-size: .9rem;
  line-height: 1.5;
  color: var(--c-grey);
  text-decoration: none;
  transition: color var(--dur);
}

.page-about .rail-list__link:hover,
.page-about .rail-list__link:focus-visible {
  color: var(--c-gold-lite);
}

.page-about .about-flow {
  display: grid;
  gap: var(--about-gap);
}

.page-about .about-block {
  scroll-margin-top: calc(var(--header-h) + 2rem);
  display: grid;
  gap: 1.5rem;
}

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

.page-about .about-copy p:last-child {
  margin-bottom: 0;
}

.page-about .about-split {
  display: grid;
  gap: 1.8rem;
  align-items: center;
}

/* ---------- 图片框 ---------- */
.page-about .media-frame {
  margin: 0;
  border: 1px solid var(--c-line);
  border-radius: var(--rad);
  background: var(--c-void);
  overflow: hidden;
  box-shadow: var(--shadow-soft);
}

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

.page-about .media-frame__caption {
  padding: .7rem .9rem .75rem;
  border-top: 1px solid var(--c-line);
  font-size: .78rem;
  line-height: 1.6;
  color: var(--c-grey);
  background: var(--c-panel);
}

/* ---------- 四个核心板块 ---------- */
.page-about .pillar-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.1rem;
}

.page-about .pillar {
  position: relative;
  display: grid;
  gap: .6rem;
  align-content: start;
  padding: 1.4rem 1.3rem 1.5rem;
  background: var(--c-panel);
  border: 1px solid var(--c-line);
  border-radius: var(--rad);
  transition: border-color var(--dur), background var(--dur);
}

.page-about .pillar:hover {
  border-color: rgba(201, 162, 75, .6);
  background: #2b1a4d;
}

.page-about .pillar__no {
  font-family: var(--font-display);
  font-size: .82rem;
  letter-spacing: .2em;
  color: var(--c-gold);
}

.page-about .pillar__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.24rem;
  letter-spacing: -0.01em;
  color: var(--c-white);
}

.page-about .pillar__text {
  margin: 0;
  font-size: .93rem;
  line-height: 1.82;
  color: var(--c-grey);
}

.page-about .pillar__link {
  margin-top: .3rem;
  align-self: end;
  font-size: .86rem;
  color: var(--c-gold-lite);
  text-decoration: none;
  border-bottom: 1px solid rgba(201, 162, 75, .4);
  justify-self: start;
  padding-bottom: 2px;
  transition: color var(--dur), border-color var(--dur);
}

.page-about .pillar__link:hover,
.page-about .pillar__link:focus-visible {
  color: var(--c-white);
  border-color: var(--c-white);
}

/* ---------- 团队 ---------- */
.page-about .crew-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--rad);
  overflow: hidden;
}

.page-about .crew {
  background: var(--c-void);
  padding: 1.25rem 1.2rem 1.35rem;
}

.page-about .crew__title {
  margin: 0 0 .5rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.02rem;
  color: var(--c-gold-lite);
}

.page-about .crew__text {
  margin: 0;
  font-size: .9rem;
  line-height: 1.8;
  color: var(--c-grey);
}

/* ---------- 折叠 ---------- */
.page-about .fold {
  border: 1px solid var(--c-line);
  border-radius: var(--rad);
  background: var(--c-panel);
}

.page-about .fold__summary {
  cursor: pointer;
  list-style: none;
  padding: 1rem 1.15rem;
  font-size: .96rem;
  color: var(--c-gold-lite);
  display: flex;
  align-items: center;
  gap: .6rem;
}

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

.page-about .fold__summary::before {
  content: "＋";
  font-size: .95rem;
  color: var(--c-gold);
}

.page-about .fold[open] .fold__summary::before {
  content: "－";
}

.page-about .fold__body {
  padding: 0 1.15rem 1.2rem;
}

.page-about .fold__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: .7rem;
}

.page-about .fold__list li {
  padding-left: 1.1rem;
  position: relative;
  font-size: .92rem;
  line-height: 1.8;
  color: var(--c-grey);
}

.page-about .fold__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .78em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c-gold);
}

.page-about .fold__list strong {
  color: var(--c-white);
  font-weight: 600;
}

/* ---------- 更新节奏 ---------- */
.page-about .cadence {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--c-line);
}

.page-about .cadence__item {
  display: grid;
  gap: .35rem;
  padding: 1.15rem 0 1.2rem;
  border-bottom: 1px solid var(--c-line);
}

.page-about .cadence__when {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: .96rem;
  letter-spacing: .06em;
  color: var(--c-gold);
}

.page-about .cadence__what {
  margin: 0;
  font-size: .95rem;
  line-height: 1.85;
  color: var(--c-grey);
}

/* ---------- 使用路径 ---------- */
.page-about .path {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1.1rem;
  counter-reset: none;
}

.page-about .path__step {
  position: relative;
  padding: 1.25rem 1.2rem 1.3rem 1.35rem;
  background: var(--c-void);
  border-left: 2px solid var(--c-gold);
  border-radius: 0 var(--rad) var(--rad) 0;
  display: grid;
  gap: .5rem;
}

.page-about .path__no {
  font-family: var(--font-display);
  font-size: .78rem;
  letter-spacing: .2em;
  color: var(--c-gold);
}

.page-about .path__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.12rem;
  letter-spacing: -0.01em;
  color: var(--c-white);
}

.page-about .path__text {
  margin: 0;
  font-size: .93rem;
  line-height: 1.82;
  color: var(--c-grey);
}

/* ---------- 收束 ---------- */
.page-about .about-close {
  margin-top: clamp(2rem, 5vw, 3.2rem);
  padding: clamp(1.6rem, 4vw, 2.8rem);
  border: 1px solid var(--c-line);
  border-radius: var(--rad);
  background: linear-gradient(136deg, rgba(201, 162, 75, .14), rgba(201, 162, 75, 0) 58%), var(--c-panel);
  display: grid;
  gap: .9rem;
  justify-items: start;
}

.page-about .about-close__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.3rem, 3vw, 1.85rem);
  letter-spacing: -0.015em;
  color: var(--c-white);
}

.page-about .about-close__text {
  margin: 0;
  max-width: 46ch;
  font-size: .95rem;
  line-height: 1.85;
  color: var(--c-grey);
}

.page-about .about-close__actions {
  margin-top: .5rem;
  display: flex;
  flex-wrap: wrap;
  gap: .8rem;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .pillar-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (min-width: 760px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: 2.6rem;
  }

  .page-about .about-split--reverse > .media-frame {
    order: 2;
  }

  .page-about .cadence__item {
    grid-template-columns: 6.5rem minmax(0, 1fr);
    align-items: baseline;
    gap: 1.4rem;
  }

  .page-about .path {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.2rem;
  }

  .page-about .pillar:nth-child(even) {
    transform: translateY(1.4rem);
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    gap: 4rem;
  }

  .page-about .about-layout {
    grid-template-columns: 212px minmax(0, 1fr);
    gap: 3.6rem;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 1.6rem);
    align-self: start;
    padding-left: 1.4rem;
    border-left: 1px solid var(--c-line);
  }

  .page-about .rail-list {
    flex-direction: column;
    gap: .95rem;
  }

  .page-about .rail-list__item {
    position: relative;
  }

  .page-about .rail-list__item::before {
    content: "";
    position: absolute;
    left: -1.4rem;
    top: .52em;
    width: 7px;
    height: 7px;
    margin-left: -4px;
    border-radius: 50%;
    background: var(--c-line);
    transition: background var(--dur), box-shadow var(--dur);
  }

  .page-about .rail-list__item:hover::before,
  .page-about .rail-list__item:has(.is-active)::before {
    background: var(--c-gold);
    box-shadow: 0 0 0 3px rgba(201, 162, 75, .18);
  }

  .page-about .crew-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .page-about .about-hero__title br {
    display: none;
  }

  .page-about .about-hero__facts {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .pillar,
  .page-about .rail-list__link,
  .page-about .pillar__link {
    transition: none;
  }

  .page-about .pillar:nth-child(even) {
    transform: none;
  }
}