.page-about {
  --about-pad: clamp(52px, 9vw, 108px);
  --about-rule: var(--yh-line);
  --about-soft: var(--yh-line-soft);
  position: relative;
  overflow-x: clip;
  padding-bottom: clamp(40px, 7vw, 88px);
}

.page-about::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 780px;
  pointer-events: none;
  background:
    radial-gradient(560px 380px at 82% 6%, rgba(123, 92, 255, .22), transparent 70%),
    radial-gradient(520px 340px at 8% 24%, rgba(255, 106, 43, .14), transparent 72%);
  z-index: -1;
}

.page-about img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding-top: clamp(92px, 14vw, 148px);
  padding-bottom: clamp(32px, 5vw, 56px);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 5vw, 44px);
  margin-top: clamp(24px, 4vw, 40px);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--yh-font-editorial);
  font-weight: 700;
  font-size: clamp(34px, 8vw, 66px);
  line-height: 1.16;
  letter-spacing: -.01em;
  color: var(--yh-ice);
  text-shadow: 0 0 40px rgba(123, 92, 255, .35);
}

.page-about .about-hero__title span {
  color: var(--yh-coral);
  text-shadow: 0 0 44px rgba(255, 106, 43, .38);
}

.page-about .about-hero__lede {
  margin: 22px 0 0;
  max-width: 56ch;
  font-family: var(--yh-font-body);
  font-size: clamp(15px, 2.4vw, 17px);
  line-height: 1.8;
  color: var(--yh-mist);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-hero__fig {
  border-radius: var(--yh-radius);
  clip-path: polygon(0 0, 100% 0, 100% 90%, 88% 100%, 0 100%);
  border: 1px solid var(--yh-line);
  box-shadow: 0 26px 60px rgba(4, 10, 24, .55);
}

.page-about .about-hero__fig img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 6 / 7;
}

/* ---------- 横向数据带 ---------- */

.page-about .about-band {
  margin-top: clamp(24px, 5vw, 48px);
  border-top: 1px solid var(--about-rule);
  border-bottom: 1px solid var(--about-rule);
  background:
    linear-gradient(100deg, rgba(27, 47, 90, .82), rgba(13, 30, 63, .42));
  backdrop-filter: blur(12px);
}

.page-about .about-band__inner {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-soft);
}

.page-about .about-band__item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 22px 18px;
  background: #0A1730;
}

.page-about .about-band__num {
  font-size: clamp(24px, 4.6vw, 34px);
  font-weight: 600;
  line-height: 1;
  color: var(--yh-orange);
}

.page-about .about-band__label {
  font-size: 13px;
  line-height: 1.55;
  color: var(--yh-mist);
}

/* ---------- 章节目录 ---------- */

.page-about .about-toc {
  padding-top: clamp(28px, 4vw, 44px);
}

.page-about .about-toc__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 18px;
  padding: 14px 18px;
  border: 1px solid var(--yh-line);
  border-radius: var(--yh-radius);
  background: rgba(27, 47, 90, .5);
  backdrop-filter: blur(14px);
}

.page-about .about-toc .yh-toc__title {
  margin: 0;
  font-family: var(--yh-font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--yh-orange);
}

.page-about .about-toc__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-toc .yh-toc__link {
  display: inline-block;
  padding: 6px 13px;
  border-radius: var(--yh-pill);
  border: 1px solid var(--about-soft);
  font-family: var(--yh-font-mono);
  font-size: 12px;
  letter-spacing: .02em;
  color: var(--yh-mist);
  text-decoration: none;
  transition: color .2s ease, border-color .2s ease, background-color .2s ease;
}

.page-about .about-toc .yh-toc__link:hover,
.page-about .about-toc .yh-toc__link:focus-visible {
  color: var(--yh-ice);
  border-color: rgba(255, 106, 43, .6);
}

.page-about .about-toc .yh-toc__link[aria-current="true"] {
  color: var(--yh-space);
  background: var(--yh-orange);
  border-color: var(--yh-orange);
}

/* ---------- 章节骨架 ---------- */

.page-about .about-chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 36px);
  padding-top: var(--about-pad);
}

.page-about .about-chapter__title {
  margin: 12px 0 0;
  font-family: var(--yh-font-editorial);
  font-weight: 700;
  font-size: clamp(26px, 5.2vw, 42px);
  line-height: 1.3;
  color: var(--yh-ice);
}

.page-about .about-chapter__body {
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--yh-ink-soft);
}

.page-about .about-chapter__body > p {
  margin: 0 0 18px;
}

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

.page-about .about-chapter__body a {
  color: var(--yh-coral);
  text-decoration-color: rgba(255, 138, 76, .5);
  text-underline-offset: 3px;
}

.page-about .about-chapter__body a:hover {
  color: var(--yh-ice);
}

/* ---------- 内容频道 ---------- */

.page-about .about-channels {
  margin: 26px 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--about-soft);
}

.page-about .about-channels__item {
  position: relative;
  isolation: isolate;
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 4px 14px;
  padding: 20px 12px 20px 8px;
  border-bottom: 1px solid var(--about-soft);
}

.page-about .about-channels__item::before {
  content: "";
  position: absolute;
  inset: 4px 0;
  z-index: -1;
  border-radius: var(--yh-radius-sm);
  background: linear-gradient(90deg, rgba(123, 92, 255, .26), rgba(255, 106, 43, .16) 62%, transparent);
  transform: skewX(-9deg) scaleX(0);
  transform-origin: left center;
  transition: transform .38s cubic-bezier(.2, .7, .3, 1);
}

.page-about .about-channels__item:hover::before,
.page-about .about-channels__item:focus-within::before {
  transform: skewX(-9deg) scaleX(1);
}

.page-about .about-channels__idx {
  grid-row: 1 / span 2;
  font-size: 12px;
  line-height: 1.9;
  color: var(--yh-violet);
}

.page-about .about-channels__name {
  margin: 0;
  font-family: var(--yh-font-display);
  font-size: 17px;
  letter-spacing: .02em;
  color: var(--yh-ice);
}

.page-about .about-channels__desc {
  margin: 0;
  grid-column: 2;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--yh-mist);
}

/* ---------- 团队 ---------- */

.page-about .about-team__layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 34px);
}

.page-about .about-team__fig {
  border-radius: var(--yh-radius);
  border: 1px solid var(--yh-line);
  overflow: hidden;
  background: rgba(27, 47, 90, .5);
}

.page-about .about-team__fig img {
  width: 100%;
  aspect-ratio: 7 / 4;
  object-fit: cover;
}

.page-about .about-team__panels {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .about-team__item {
  border: 1px solid var(--about-soft);
  border-radius: var(--yh-radius-sm);
  background: rgba(27, 47, 90, .42);
  backdrop-filter: blur(10px);
  transition: border-color .24s ease, background-color .24s ease;
}

.page-about .about-team__item[open] {
  border-color: rgba(255, 106, 43, .45);
  background: rgba(27, 47, 90, .62);
}

.page-about .about-team__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
  font-family: var(--yh-font-body);
  font-size: 15px;
  color: var(--yh-ice);
}

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

.page-about .about-team__summary::after {
  content: "+";
  flex: none;
  width: 22px;
  height: 22px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  border: 1px solid var(--about-rule);
  font-family: var(--yh-font-mono);
  font-size: 13px;
  color: var(--yh-orange);
}

.page-about .about-team__item[open] .about-team__summary::after {
  content: "−";
  border-color: rgba(255, 106, 43, .6);
}

.page-about .about-team__role {
  font-weight: 500;
  letter-spacing: .02em;
}

.page-about .about-team__count {
  margin-left: auto;
  font-size: 13px;
  color: var(--yh-lime);
}

.page-about .about-team__body {
  padding: 0 18px 18px;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--yh-mist);
}

.page-about .about-team__body p {
  margin: 0;
  border-top: 1px solid var(--about-soft);
  padding-top: 14px;
}

/* ---------- 年份带 ---------- */

.page-about .about-yearline {
  margin-top: var(--about-pad);
  padding-block: clamp(44px, 7vw, 76px);
  border-top: 1px solid var(--about-rule);
  border-bottom: 1px solid var(--about-rule);
  background:
    radial-gradient(640px 300px at 18% 0%, rgba(123, 92, 255, .2), transparent 72%),
    linear-gradient(180deg, rgba(13, 30, 63, .78), rgba(7, 19, 43, .3));
}

.page-about .about-yearline__head {
  max-width: 40ch;
}

.page-about .about-yearline__list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  margin: clamp(26px, 4vw, 44px) 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-yearline__item {
  position: relative;
  padding: 22px 4px 22px 26px;
  border-bottom: 1px solid var(--about-soft);
}

.page-about .about-yearline__item::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 28px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--yh-violet);
  box-shadow: 0 0 0 4px rgba(123, 92, 255, .16);
  transition: background-color .3s ease, box-shadow .3s ease;
}

.page-about .about-yearline__item.is-visible::before {
  background: var(--yh-orange);
  box-shadow: 0 0 0 4px rgba(255, 106, 43, .2), 0 0 18px rgba(255, 106, 43, .55);
}

.page-about .about-yearline__year {
  display: block;
  font-size: clamp(20px, 4.4vw, 26px);
  font-weight: 600;
  line-height: 1;
  color: var(--yh-coral);
}

.page-about .about-yearline__name {
  margin: 10px 0 6px;
  font-family: var(--yh-font-display);
  font-size: 15px;
  letter-spacing: .04em;
  color: var(--yh-ice);
}

.page-about .about-yearline__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--yh-mist);
}

.page-about .about-yearline__fig {
  margin-top: clamp(26px, 4vw, 40px);
  border-radius: var(--yh-radius);
  border: 1px solid var(--yh-line);
  overflow: hidden;
}

.page-about .about-yearline__fig img {
  width: 100%;
  aspect-ratio: 16 / 7;
  object-fit: cover;
}

/* ---------- 覆盖与支持 ---------- */

.page-about .about-reach__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin: 24px 0;
}

.page-about .about-reach__card {
  padding: 18px 20px;
  border: 1px solid var(--about-soft);
  border-left: 3px solid var(--yh-lime);
  border-radius: var(--yh-radius-sm);
  background: rgba(27, 47, 90, .38);
}

.page-about .about-reach__k {
  margin: 0 0 8px;
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--yh-lime);
}

.page-about .about-reach__v {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--yh-mist);
}

/* ---------- 结尾行动区 ---------- */

.page-about .about-cta {
  padding-top: var(--about-pad);
}

.page-about .about-cta__panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 34px);
  padding: clamp(26px, 5vw, 48px);
  border: 1px solid var(--yh-line);
  border-radius: var(--yh-radius);
  background:
    linear-gradient(125deg, rgba(27, 47, 90, .82), rgba(13, 30, 63, .6));
  box-shadow: 0 24px 60px rgba(4, 10, 24, .5);
}

.page-about .about-cta__title {
  margin: 12px 0 0;
  font-family: var(--yh-font-editorial);
  font-size: clamp(24px, 4.6vw, 36px);
  line-height: 1.32;
  color: var(--yh-ice);
}

.page-about .about-cta__lede {
  margin: 16px 0 0;
  max-width: 52ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--yh-mist);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-content: start;
}

/* ---------- 回到顶部 ---------- */

.page-about .about-back {
  display: flex;
  justify-content: flex-end;
  padding-top: clamp(24px, 4vw, 40px);
}

.page-about .about-back__link {
  position: static;
  font-family: var(--yh-font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--yh-mist);
  text-decoration: none;
  border: 1px solid var(--about-rule);
  border-radius: var(--yh-pill);
  padding: 9px 16px;
}

.page-about .about-back__link:hover {
  color: var(--yh-ice);
  border-color: rgba(255, 106, 43, .55);
}

/* ---------- 响应式 ---------- */

@media (min-width: 700px) {
  .page-about .about-band__inner {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-band__item {
    padding: 26px 20px;
  }

  .page-about .about-channels__item {
    grid-template-columns: 56px 150px minmax(0, 1fr);
    align-items: baseline;
    gap: 0 18px;
    padding: 22px 16px 22px 10px;
  }

  .page-about .about-channels__idx {
    grid-row: auto;
  }

  .page-about .about-channels__desc {
    grid-column: auto;
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
  }

  .page-about .about-toc {
    position: sticky;
    top: 84px;
    z-index: 6;
  }

  .page-about .about-toc__inner {
    padding: 14px 22px;
  }

  .page-about .about-chapter {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: clamp(32px, 5vw, 72px);
  }

  .page-about .about-team__layout {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: start;
  }

  .page-about .about-yearline__list {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    border-bottom: 1px solid var(--about-soft);
  }

  .page-about .about-yearline__item {
    padding: 26px 18px 26px 0;
    border-bottom: 0;
    border-right: 1px solid var(--about-soft);
  }

  .page-about .about-yearline__item:last-child {
    border-right: 0;
  }

  .page-about .about-yearline__item::before {
    left: 0;
    top: 30px;
  }

  .page-about .about-yearline__item {
    padding-left: 22px;
  }

  .page-about .about-cta__panel {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: center;
  }

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

@media (min-width: 1180px) {
  .page-about .about-hero__fig img {
    aspect-ratio: 5 / 6;
  }

  .page-about .about-chapter__body {
    font-size: 16.5px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-channels__item::before,
  .page-about .about-yearline__item::before,
  .page-about .about-toc .yh-toc__link {
    transition: none;
  }

  .page-about .about-channels__item::before {
    transform: skewX(-9deg) scaleX(1);
    opacity: 0;
  }

  .page-about .about-channels__item:hover::before {
    opacity: 1;
  }
}