.page-about {
  --about-gutter: 20px;
  --about-rail-line: rgba(201, 211, 218, 0.22);
  background-color: var(--ink);
  color: var(--text);
  overflow-x: clip;
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

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

.page-about .container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding-left: var(--about-gutter);
  padding-right: var(--about-gutter);
}

.page-about .mono {
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}

/* ---------- 首屏框景 ---------- */

.page-about .about-hero {
  position: relative;
  padding: calc(var(--header-h) + 36px) 0 56px;
  background-image:
    radial-gradient(90% 68% at 88% 2%, rgba(62, 134, 181, 0.28) 0%, rgba(11, 26, 43, 0) 62%),
    radial-gradient(58% 48% at 4% 98%, rgba(176, 122, 60, 0.18) 0%, rgba(11, 26, 43, 0) 70%),
    linear-gradient(180deg, #0B1A2B 0%, #12283F 100%);
  border-bottom: 1px solid var(--about-rail-line);
}

.page-about .about-hero__frame {
  position: relative;
  padding: 22px 18px 28px;
  border: 1px solid var(--about-rail-line);
  background-image:
    linear-gradient(rgba(201, 211, 218, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 211, 218, 0.055) 1px, transparent 1px);
  background-size: 44px 44px;
}

.page-about .about-hero__frame::before,
.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  width: 18px;
  height: 18px;
  border: 2px solid var(--copper);
}

.page-about .about-hero__frame::before {
  top: -1px;
  left: -1px;
  border-right: 0;
  border-bottom: 0;
}

.page-about .about-hero__frame::after {
  right: -1px;
  bottom: -1px;
  border-top: 0;
  border-left: 0;
}

.page-about .about-crumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 26px;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}

.page-about .breadcrumbs__item {
  color: var(--slate);
}

.page-about .breadcrumbs__item + .breadcrumbs__item::before {
  content: "/";
  margin-right: 8px;
  color: var(--slate);
}

.page-about .breadcrumbs__link {
  color: var(--copper-2);
  text-decoration: none;
}

.page-about .breadcrumbs__link:hover,
.page-about .breadcrumbs__link:focus-visible {
  text-decoration: underline;
}

.page-about .about-hero__grid {
  display: grid;
  gap: 32px;
}

.page-about .about-kicker {
  margin: 0 0 14px;
  font-size: 12px;
  color: var(--copper-2);
}

.page-about .about-hero__title {
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(28px, 6.2vw, 54px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--text);
}

.page-about .about-hero__intro {
  margin: 0;
  max-width: 34em;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  color: rgba(247, 250, 252, 0.84);
}

.page-about .about-hero__marks {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 16px;
  margin: 32px 0 0;
  padding: 20px 0 0;
  list-style: none;
  border-top: 1px solid var(--about-rail-line);
}

.page-about .about-mark {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding-left: 12px;
  border-left: 3px solid var(--copper);
}

.page-about .about-mark__num {
  font-size: 22px;
  line-height: 1.1;
  color: var(--copper-2);
}

.page-about .about-mark__txt {
  font-size: 13px;
  color: var(--slate);
}

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

.page-about .image-frame {
  margin: 0;
  border: 1px solid var(--about-rail-line);
  background-color: var(--ink-2);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .image-frame__canvas {
  position: relative;
  overflow: hidden;
  background-image:
    linear-gradient(180deg, rgba(62, 134, 181, 0.16) 0%, rgba(11, 26, 43, 0.5) 100%);
}

.page-about .image-frame__canvas img {
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.72) contrast(1.06);
}

.page-about .image-frame__caption {
  padding: 10px 14px;
  border-top: 1px solid var(--about-rail-line);
  font-size: 12px;
  color: var(--slate);
}

/* ---------- 索引轴 + 内容流 ---------- */

.page-about .about-flow {
  padding-bottom: 88px;
}

.page-about .about-flow__inner {
  display: grid;
  gap: 0;
}

.page-about .about-rail {
  border-bottom: 1px solid var(--about-rail-line);
  background-color: rgba(11, 26, 43, 0.94);
}

.page-about .about-rail__list {
  display: flex;
  gap: 4px;
  margin: 0;
  padding: 10px 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .about-rail__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-rail__item {
  flex: 0 0 auto;
}

.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 7px;
  padding: 6px 10px;
  border-left: 2px solid transparent;
  font-size: 12px;
  color: var(--slate);
  text-decoration: none;
  white-space: nowrap;
}

.page-about .about-rail__idx {
  color: var(--copper);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible,
.page-about .about-rail__link.is-active {
  color: var(--ice);
  border-left-color: var(--copper);
}

.page-about .about-rail__link.is-active .about-rail__idx {
  color: var(--copper-2);
}

/* ---------- 章节通用 ---------- */

.page-about .about-block {
  padding-top: 76px;
}

.page-about .about-block__index {
  margin: 0 0 18px;
  padding-bottom: 10px;
  display: inline-block;
  border-bottom: 4px solid var(--copper);
  font-size: 12px;
  color: var(--copper-2);
}

.page-about .about-block__title {
  margin: 0 0 20px;
  max-width: 22em;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(23px, 4.4vw, 36px);
  line-height: 1.2;
  letter-spacing: -0.015em;
  color: var(--text);
}

.page-about .about-block__lead {
  margin: 0 0 34px;
  max-width: 40em;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  color: rgba(247, 250, 252, 0.78);
}

.page-about .about-block__body--prose p {
  margin: 0 0 22px;
  max-width: 36em;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.9;
  color: rgba(247, 250, 252, 0.84);
}

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

/* ---------- 引用块 ---------- */

.page-about .about-quote {
  margin: 34px 0;
  padding: 24px 22px;
  background-color: var(--paper);
  border-left: 4px solid var(--copper);
  border-radius: var(--radius);
}

.page-about .about-quote blockquote {
  margin: 0;
}

.page-about .about-quote blockquote p {
  margin: 0;
  max-width: 30em;
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .about-quote__source {
  margin: 14px 0 0;
  font-size: 12px;
  color: var(--copper);
}

/* ---------- 发展轴线 ---------- */

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

.page-about .about-scale {
  position: relative;
  display: flex;
  justify-content: space-between;
  margin: 0 0 46px;
  padding-top: 5px;
}

.page-about .about-scale::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background-color: var(--about-rail-line);
}

.page-about .about-scale span {
  width: 11px;
  height: 11px;
  background-color: var(--copper);
  transform: translateY(-5px);
}

.page-about .about-stages {
  display: grid;
  gap: 26px;
}

.page-about .about-stage {
  position: relative;
}

.page-about .about-stage__num {
  margin: 0 0 10px;
  font-size: 13px;
  color: var(--copper-2);
}

.page-about .about-stage__body {
  padding: 20px 18px 22px;
  border: 1px solid var(--about-rail-line);
  border-left: 3px solid var(--copper);
  border-radius: var(--radius);
}

.page-about .about-stage__title {
  margin: 0 0 12px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 19px;
  line-height: 1.35;
  color: var(--text);
}

.page-about .about-stage__lead {
  margin: 0;
  max-width: 34em;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: rgba(247, 250, 252, 0.76);
}

.page-about .about-stage__trigger {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 18px;
  padding: 8px 14px;
  background-color: transparent;
  border: 1px solid var(--ice-2);
  border-radius: var(--radius);
  color: var(--ice);
  font-family: var(--font-sans);
  font-size: 13px;
  cursor: pointer;
  transition: border-color 200ms var(--ease), color 200ms var(--ease);
}

.page-about .about-stage__trigger:hover {
  border-color: var(--ice);
  color: var(--text);
}

.page-about .about-stage__trigger:focus-visible {
  outline: 2px solid var(--ice);
  outline-offset: 2px;
}

.page-about .about-stage__arrow {
  display: inline-block;
  transition: transform 240ms var(--ease);
}

.page-about [data-accordion-trigger][aria-expanded="true"] .about-stage__arrow {
  transform: rotate(90deg);
}

.page-about .about-stage__panel {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--about-rail-line);
}

.page-about .accordion__body p {
  margin: 0 0 14px;
  max-width: 34em;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: rgba(247, 250, 252, 0.8);
}

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

/* ---------- 三栏分工 ---------- */

.page-about .about-trio {
  display: grid;
  gap: 18px;
}

.page-about .about-trio__col {
  padding: 22px 20px 24px;
  background-color: rgba(107, 126, 140, 0.12);
  border: 1px solid var(--about-rail-line);
  border-top: 4px solid var(--slate);
  border-radius: var(--radius);
}

.page-about .about-trio__col--service {
  border-top-color: var(--copper);
}

.page-about .about-trio__col--guide {
  border-top-color: var(--ice);
}

.page-about .about-trio__col--notice {
  border-top-color: var(--copper-2);
}

.page-about .about-trio__tag {
  margin: 0 0 12px;
  font-size: 12px;
  color: var(--copper-2);
}

.page-about .about-trio__title {
  margin: 0 0 14px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.4;
  color: var(--text);
}

.page-about .about-trio__col p {
  margin: 0 0 18px;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: rgba(247, 250, 252, 0.78);
}

.page-about .text-link {
  display: inline-block;
  color: var(--ice);
  font-family: var(--font-sans);
  font-size: 14px;
  text-decoration: none;
  border-bottom: 1px solid var(--ice-2);
  padding-bottom: 2px;
}

.page-about .text-link:hover,
.page-about .text-link:focus-visible {
  color: var(--text);
  border-bottom-color: var(--copper-2);
}

.page-about .about-cross {
  margin: 26px 0 0;
  max-width: 38em;
  padding-left: 16px;
  border-left: 2px solid var(--copper);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: rgba(247, 250, 252, 0.72);
}

/* ---------- 维护团队 ---------- */

.page-about .about-team {
  display: grid;
  gap: 26px;
}

.page-about .about-team__grid {
  display: grid;
  gap: 16px;
}

.page-about .panel {
  border-radius: var(--radius);
}

.page-about .panel--paper {
  background-color: var(--paper);
  color: var(--ink);
}

.page-about .panel--slate {
  background-color: rgba(107, 126, 140, 0.16);
  border: 1px solid var(--about-rail-line);
  color: var(--text);
}

.page-about .about-team__card {
  padding: 20px 18px;
  border-left: 3px solid var(--copper);
}

.page-about .about-team__role {
  margin: 0 0 12px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 17px;
  color: var(--ink);
}

.page-about .about-team__card p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: #1B2A38;
}

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

.page-about .about-team__note {
  margin-top: 26px;
  padding: 22px 20px;
}

.page-about .about-team__note p {
  margin: 0 0 16px;
  max-width: 38em;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: rgba(247, 250, 252, 0.82);
}

/* ---------- 适配与更新 ---------- */

.page-about .about-cycle {
  display: grid;
  gap: 16px;
  margin: 34px 0 0;
}

.page-about .about-cycle__item {
  padding: 18px 0 0;
  border-top: 2px solid var(--copper);
}

.page-about .about-cycle__num {
  margin: 0 0 10px;
  font-size: 13px;
  color: var(--copper-2);
}

.page-about .about-cycle__title {
  margin: 0 0 10px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.4;
  color: var(--text);
}

.page-about .about-cycle__item p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: rgba(247, 250, 252, 0.76);
}

.page-about .about-fitness__note {
  margin-top: 32px;
  padding: 24px 20px 26px;
}

.page-about .about-fitness__title {
  margin: 0 0 14px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 19px;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .about-fitness__note p {
  margin: 0 0 14px;
  max-width: 38em;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: #1B2A38;
}

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

/* ---------- 延伸入口 ---------- */

.page-about .about-next {
  padding-bottom: 0;
}

.page-about .about-next__list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-next__link {
  display: grid;
  gap: 6px;
  padding: 18px 18px 18px 20px;
  border: 1px solid var(--about-rail-line);
  border-left: 3px solid var(--copper);
  border-radius: var(--radius);
  background-color: rgba(18, 40, 63, 0.72);
  text-decoration: none;
  transition: border-color 200ms var(--ease), transform 200ms var(--ease);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-left-color: var(--ice);
  border-left-width: 4px;
  transform: translateY(-2px);
}

.page-about .about-next__link:focus-visible {
  outline: 2px solid var(--ice);
  outline-offset: 2px;
}

.page-about .about-next__label {
  font-size: 13px;
  color: var(--copper-2);
}

.page-about .about-next__desc {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.7;
  color: rgba(247, 250, 252, 0.82);
}

/* ---------- 桌面布局 ---------- */

@media (min-width: 720px) {
  .page-about {
    --about-gutter: 28px;
  }

  .page-about .about-hero {
    padding-top: calc(var(--header-h) + 52px);
    padding-bottom: 76px;
  }

  .page-about .about-hero__frame {
    padding: 30px 28px 36px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-trio {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .about-team__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

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

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

@media (min-width: 1000px) {
  .page-about .about-flow {
    padding-bottom: 128px;
  }

  .page-about .about-flow__inner {
    grid-template-columns: var(--axis-w) minmax(0, 1fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    background-color: transparent;
    border-bottom: 0;
    border-left: 1px solid var(--about-rail-line);
    padding-left: 14px;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 2px;
    padding: 0;
    overflow: visible;
  }

  .page-about .about-rail__link {
    padding: 6px 0 6px 10px;
  }

  .page-about .about-block {
    padding-top: 108px;
  }

  .page-about .about-block:first-child {
    padding-top: 60px;
  }

  .page-about .about-block__title {
    font-size: 34px;
  }

  .page-about .about-stages {
    gap: 34px;
  }

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

  .page-about .about-stage__col {
    display: grid;
    grid-template-columns: 92px minmax(0, 1fr);
    gap: 24px;
    align-items: start;
  }

  .page-about .about-stage--odd .about-stage__col {
    grid-column: 1 / span 10;
  }

  .page-about .about-stage--even .about-stage__col {
    grid-column: 3 / span 10;
  }

  .page-about .about-stage__num {
    margin-top: 4px;
    text-align: right;
  }

  .page-about .about-stage__body {
    padding: 24px 26px 26px;
  }

  .page-about .about-stage__title {
    font-size: 21px;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    gap: 32px;
    align-items: start;
  }

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

  .page-about .about-team__figure {
    position: sticky;
    top: calc(var(--header-h) + 84px);
  }

  .page-about .about-block__body--prose p {
    max-width: 34em;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-next__link,
  .page-about .about-stage__arrow,
  .page-about .about-stage__trigger {
    transition: none;
  }

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