.page-about {
  --about-tint: rgba(200, 255, 61, 0.08);
  --about-blue-tint: rgba(63, 169, 255, 0.1);
  --about-gap: clamp(20px, 4vw, 40px);
  padding-bottom: clamp(40px, 7vw, 88px);
  overflow-x: clip;
}

.page-about .about-link {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(63, 169, 255, 0.45);
  transition: color 180ms ease, border-color 180ms ease;
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--neon);
  border-color: var(--neon-dim);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(28px, 5vw, 56px) 0 clamp(36px, 6vw, 80px);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(24px, 4vw, 48px);
  align-items: start;
}

.page-about .about-hero__lead {
  grid-column: 1 / -1;
}

.page-about .about-hero__title {
  margin: 14px 0 20px;
  letter-spacing: -0.02em;
  line-height: 0.98;
}

.page-about .about-hero__intro {
  max-width: 52ch;
  color: var(--white);
  opacity: 0.88;
  margin: 0;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 4vw, 36px);
}

.page-about .about-hero__side {
  grid-column: 1 / -1;
  padding: clamp(20px, 3vw, 28px);
  background: linear-gradient(158deg, var(--panel) 0%, var(--panel-2) 100%);
  border-left: 2px solid var(--neon);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.page-about .about-hero__side-title {
  margin: 0 0 14px;
  color: var(--mist);
}

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

.page-about .about-index__item {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  grid-template-rows: auto auto;
  align-items: baseline;
  gap: 2px 10px;
  padding: 12px 2px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-index__no {
  grid-row: 1 / 3;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--neon);
}

.page-about .about-index__label {
  font-size: 16px;
  color: var(--white);
}

.page-about .about-index__note {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .about-crew {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-top: 20px;
}

.page-about .about-crew__num {
  margin: 0;
  font-family: var(--font-mono);
  color: var(--neon);
  line-height: 1;
  white-space: nowrap;
}

.page-about .about-crew__text {
  margin: 0;
  font-size: 14px;
  color: var(--mist);
  line-height: 1.7;
}

@media (min-width: 900px) {
  .page-about .about-hero__lead {
    grid-column: span 7;
  }

  .page-about .about-hero__side {
    grid-column: span 5;
    position: sticky;
    top: calc(var(--rail-h) + 28px);
  }
}

/* ---------- 通用章节 ---------- */
.page-about .about-section {
  padding: clamp(36px, 6vw, 76px) 0;
}

.page-about .about-section__head {
  max-width: 62ch;
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .about-section__head .section-title {
  margin: 10px 0 0;
}

.page-about .about-section__lead {
  margin: 16px 0 0;
  color: var(--mist);
  font-size: 16px;
  line-height: 1.75;
  max-width: 60ch;
}

/* ---------- 主张 ---------- */
.page-about .manifesto__lead {
  margin: 0 0 clamp(24px, 4vw, 40px);
  padding-left: clamp(14px, 2vw, 22px);
  border-left: 2px solid var(--neon-dim);
  font-size: clamp(17px, 2vw, 20px);
  line-height: 1.75;
  color: var(--white);
  max-width: 68ch;
}

.page-about .manifesto__rail {
  display: grid;
  gap: 1px;
  background: var(--line);
}

.page-about .manifesto__item {
  background: var(--ink);
  padding: clamp(18px, 3vw, 26px) clamp(16px, 2.4vw, 24px);
}

.page-about .manifesto__no {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--mist);
  transition: color 280ms ease;
}

.page-about .manifesto__item.is-current .manifesto__no {
  color: var(--neon);
}

.page-about .manifesto__title {
  margin: 10px 0 8px;
  font-size: clamp(18px, 2.4vw, 24px);
  font-weight: 700;
  color: var(--white);
}

.page-about .manifesto__item p {
  margin: 0;
  color: var(--mist);
  font-size: 15px;
  line-height: 1.75;
  max-width: 52ch;
}

@media (min-width: 780px) {
  .page-about .manifesto__rail {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .manifesto__item:nth-child(2) {
    background: var(--panel);
  }
}

/* ---------- 六年路径 ---------- */
.page-about .path {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 40px);
}

.page-about .year-index {
  display: flex;
  align-items: center;
  gap: 10px;
  overflow-x: auto;
  padding-bottom: 4px;
  scrollbar-width: none;
}

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

.page-about .year-index__label {
  color: var(--mist);
  white-space: nowrap;
}

.page-about .year-index__item {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 62px;
  padding: 6px 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--mist);
  text-decoration: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  transition: color 200ms ease, border-color 200ms ease, background-color 200ms ease;
}

.page-about .year-index__item:hover,
.page-about .year-index__item:focus-visible {
  color: var(--neon);
  border-color: var(--neon-dim);
  background: var(--neon-soft);
}

.page-about .path__list {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .path__list::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--neon-dim), var(--line) 45%, transparent);
}

.page-about .path__item {
  position: relative;
  padding: 0 0 clamp(26px, 4vw, 42px) clamp(24px, 3vw, 34px);
  scroll-margin-top: calc(var(--rail-h) + 28px);
}

.page-about .path__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--line);
  transition: background-color 280ms ease, border-color 280ms ease, box-shadow 280ms ease;
}

.page-about .path__item:target::before,
.page-about .path__item.is-current::before {
  background: var(--neon);
  border-color: var(--neon);
  box-shadow: 0 0 0 5px var(--neon-soft);
}

.page-about .path__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.18em;
  color: var(--mist);
  transition: color 280ms ease;
}

.page-about .path__item:target .path__year,
.page-about .path__item.is-current .path__year {
  color: var(--neon);
}

.page-about .path__title {
  margin: 8px 0 10px;
  font-size: clamp(20px, 2.6vw, 28px);
  font-weight: 700;
  color: var(--white);
  line-height: 1.3;
}

.page-about .path__item p {
  margin: 0 0 10px;
  color: var(--mist);
  font-size: 15px;
  line-height: 1.8;
  max-width: 62ch;
}

.page-about .path__tagline {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--blue) !important;
}

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

.page-about .path__caption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
}

@media (min-width: 900px) {
  .page-about .path {
    grid-template-columns: 88px minmax(0, 1fr) 280px;
    gap: clamp(24px, 3vw, 44px);
  }

  .page-about .year-index {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    overflow: visible;
    position: sticky;
    top: calc(var(--rail-h) + 32px);
    align-self: start;
  }

  .page-about .year-index__item {
    width: 100%;
    justify-content: flex-start;
    border-color: transparent;
  }

  .page-about .path__figure {
    position: sticky;
    top: calc(var(--rail-h) + 32px);
    align-self: start;
  }
}

/* ---------- 能力版图 ---------- */
.page-about .capability__figure {
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .caps {
  display: grid;
  gap: 1px;
  background: var(--line);
}

.page-about .cap {
  position: relative;
  background: var(--ink);
  padding: clamp(20px, 3vw, 30px) clamp(18px, 2.6vw, 28px);
  outline: none;
  transition: background-color 260ms ease;
}

.page-about .cap::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 2px;
  height: 0;
  background: var(--neon);
  transition: height 320ms ease;
}

.page-about .cap:hover,
.page-about .cap:focus-within,
.page-about .cap:focus-visible {
  background: var(--panel);
}

.page-about .cap:hover::after,
.page-about .cap:focus-within::after,
.page-about .cap:focus-visible::after {
  height: 100%;
}

.page-about .cap__no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.page-about .cap__title {
  margin: 8px 0 14px;
  font-size: clamp(19px, 2.4vw, 24px);
  font-weight: 700;
  color: var(--white);
}

.page-about .cap__meta {
  margin: 0;
  display: grid;
  gap: 8px;
}

.page-about .cap__row {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 10px;
  align-items: baseline;
}

.page-about .cap__row dt {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--blue);
}

.page-about .cap__row dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--white);
  opacity: 0.86;
}

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

@media (min-width: 760px) {
  .page-about .caps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (hover: hover) and (min-width: 1024px) {
  .page-about .cap__more {
    max-height: 0;
    margin-top: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 320ms ease, opacity 320ms ease, margin-top 320ms ease;
  }

  .page-about .cap:hover .cap__more,
  .page-about .cap:focus-within .cap__more {
    max-height: 220px;
    margin-top: 14px;
    opacity: 1;
  }
}

/* ---------- 专栏机制 ---------- */
.page-about .columns-section {
  position: relative;
  padding: clamp(44px, 7vw, 92px) 0;
  overflow: hidden;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .columns-section__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.24;
  filter: saturate(0.7);
  pointer-events: none;
}

.page-about .columns-section::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(96deg, rgba(5, 7, 10, 0.96) 0%, rgba(5, 7, 10, 0.74) 55%, rgba(5, 7, 10, 0.42) 100%);
  pointer-events: none;
}

.page-about .columns-section__inner {
  position: relative;
  z-index: 1;
}

.page-about .columns-section__head {
  max-width: 62ch;
  margin-bottom: clamp(24px, 4vw, 42px);
}

.page-about .columns-section__head .section-title {
  margin: 10px 0 0;
}

.page-about .columns-section__lead {
  margin: 18px 0 0;
  color: var(--white);
  opacity: 0.86;
  font-size: 16px;
  line-height: 1.8;
  max-width: 60ch;
}

.page-about .columns-section__grid {
  display: grid;
  gap: 14px;
}

.page-about .col-card {
  padding: clamp(18px, 2.6vw, 26px);
  background: rgba(14, 20, 28, 0.72);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  backdrop-filter: blur(2px);
}

.page-about .col-card--neon {
  border-left: 2px solid var(--neon);
  background: rgba(200, 255, 61, 0.06);
}

.page-about .col-card--blue {
  border-left: 2px solid var(--blue);
  background: rgba(63, 169, 255, 0.08);
}

.page-about .col-card__title {
  margin: 0 0 10px;
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
}

.page-about .col-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .columns-section__foot {
  margin: clamp(24px, 4vw, 36px) 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--white);
  opacity: 0.86;
  max-width: 64ch;
}

@media (min-width: 760px) {
  .page-about .columns-section__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
  }
}

@media (min-width: 1180px) {
  .page-about .columns-section__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 合作 ---------- */
.page-about .coop {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}

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

.page-about .coop__item {
  padding: clamp(18px, 2.8vw, 26px) clamp(14px, 2vw, 20px);
  border-bottom: 1px solid var(--line);
  position: relative;
  transition: background-color 260ms ease, padding-left 260ms ease;
}

.page-about .coop__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 0;
  height: 100%;
  background: var(--neon-soft);
  transition: width 280ms ease;
  z-index: -1;
}

.page-about .coop__item:hover {
  padding-left: clamp(20px, 2.6vw, 30px);
}

.page-about .coop__title {
  margin: 0 0 8px;
  font-size: clamp(18px, 2.2vw, 22px);
  font-weight: 700;
  color: var(--white);
}

.page-about .coop__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist);
  max-width: 58ch;
}

.page-about .coop__side {
  padding: clamp(20px, 3vw, 28px);
  background: linear-gradient(200deg, var(--panel-2), var(--panel));
  border-radius: var(--radius);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
}

.page-about .coop__side .section-index {
  color: var(--mist);
  margin: 0 0 12px;
}

.page-about .coop__steps-list,
.page-about .coop__kit-list {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
}

.page-about .coop__steps-list li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 12px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--white);
  opacity: 0.88;
}

.page-about .coop__dot {
  position: absolute;
  left: 0;
  top: 8px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--neon);
}

.page-about .coop__kit-list li {
  position: relative;
  padding-left: 16px;
  margin-bottom: 8px;
  font-size: 14px;
  line-height: 1.72;
  color: var(--mist);
}

.page-about .coop__kit-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 1px;
  background: var(--blue);
}

.page-about .coop__cta {
  display: inline-flex;
  margin-top: 4px;
}

@media (min-width: 980px) {
  .page-about .coop {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }
}

/* ---------- 收尾 ---------- */
.page-about .about-close {
  padding: clamp(40px, 7vw, 84px) 0 clamp(12px, 3vw, 28px);
}

.page-about .about-close__inner {
  position: relative;
  padding-top: clamp(30px, 5vw, 52px);
}

.page-about .about-close__trace {
  display: block;
  width: 100%;
  height: 72px;
  color: var(--neon);
  opacity: 0.55;
  margin-bottom: clamp(18px, 3vw, 30px);
}

.page-about .about-close__text {
  margin: 0;
  font-size: clamp(18px, 2.4vw, 26px);
  line-height: 1.6;
  font-weight: 700;
  color: var(--white);
  max-width: 40ch;
}

.page-about .about-close__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(20px, 3vw, 32px);
}

@media (prefers-reduced-motion: reduce) {
  .page-about .cap__more,
  .page-about .coop__item,
  .page-about .cap,
  .page-about .year-index__item,
  .page-about .path__item::before {
    transition: none;
  }
}
</main>