.page-about {
  --about-rail-w: 238px;
  --about-edge: rgba(245, 239, 226, 0.22);
  --about-edge-dark: rgba(10, 13, 19, 0.35);
  background: var(--paper);
  color: var(--ink-900);
  font-family: var(--font-sans);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(47, 123, 255, 0.28) 0%, rgba(10, 13, 19, 0) 58%),
    var(--ink-950);
  color: var(--white);
  padding: clamp(22px, 3.4vw, 40px) 0 clamp(40px, 5.6vw, 72px);
  border-bottom: var(--line) solid var(--ink-900);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 6px;
  background: linear-gradient(90deg,
    var(--blue) 0 32%,
    var(--lime) 32% 50%,
    var(--orange) 50% 58%,
    var(--blue-deep) 58% 100%);
}

.page-about .about-hero .breadcrumb {
  color: var(--gray);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .about-hero .breadcrumb__link {
  color: var(--lime);
  text-decoration: none;
}

.page-about .about-hero .breadcrumb__link:hover,
.page-about .about-hero .breadcrumb__link:focus-visible {
  text-decoration: underline;
  outline: 2px solid var(--lime);
  outline-offset: 2px;
}

.page-about .about-hero__kicker {
  color: var(--lime);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.18em;
  margin: 0 0 14px;
  text-transform: uppercase;
}

.page-about .about-hero__title {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(1.9rem, 5.4vw, 3.9rem);
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin: 0 0 20px;
  max-width: 17ch;
}

.page-about .about-hero__lede {
  max-width: 60ch;
  margin: 0 0 clamp(26px, 4vw, 44px);
  color: var(--paper);
  font-size: clamp(0.98rem, 1.5vw, 1.1rem);
  line-height: 1.85;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  margin: 0;
  border: var(--line) solid var(--about-edge);
}

.page-about .about-hero__stat {
  padding: 14px 16px 16px;
  border-right: var(--line) solid var(--about-edge);
  border-bottom: var(--line) solid var(--about-edge);
}

.page-about .about-hero__stat:nth-child(2n) {
  border-right: 0;
}

.page-about .about-hero__stat:nth-last-child(-n + 2) {
  border-bottom: 0;
}

.page-about .about-hero__stat-label {
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--gray);
  margin: 0 0 6px;
}

.page-about .about-hero__stat-num {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.15rem, 2.4vw, 1.6rem);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-hero__stat-num--lime { color: var(--lime); }
.page-about .about-hero__stat-num--orange { color: var(--orange); }

/* ---------- 骨架与索引栏 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
}

.page-about .about-rail {
  background: var(--ink-900);
  color: var(--paper);
  padding: 18px var(--gutter);
  border-bottom: var(--line) solid var(--ink-950);
}

.page-about .about-rail__title {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  color: var(--lime);
  margin: 0 0 12px;
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(138px, 1fr));
  gap: 4px;
}

.page-about .about-rail__link {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 9px 10px;
  border: var(--line) solid transparent;
  color: var(--paper-2);
  text-decoration: none;
  font-size: 0.92rem;
  transition: background var(--t-fast) var(--ease),
              color var(--t-fast) var(--ease),
              transform var(--t-fast) var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  background: var(--paper);
  color: var(--ink-950);
  border-color: var(--ink-950);
  transform: translateX(2px);
}

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

.page-about .about-rail__num {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  font-weight: 700;
  color: var(--lime);
}

.page-about .about-rail__link:hover .about-rail__num {
  color: var(--blue-deep);
}

.page-about .about-rail__lamp {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 16px 0 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: var(--gray);
}

.page-about .about-rail__dot {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  background: var(--lime);
  box-shadow: 0 0 0 3px rgba(182, 255, 60, 0.18);
  animation: about-pulse 4s ease-in-out infinite;
}

@keyframes about-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.35; }
}

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  padding: clamp(34px, 4.6vw, 64px) var(--gutter);
  border-bottom: var(--line) solid var(--ink-900);
  scroll-margin-top: calc(var(--header-h) + 12px);
}

.page-about .about-chapter--last {
  border-bottom: 0;
}

.page-about .about-chapter--paper { background: var(--paper); }
.page-about .about-chapter--paper2 { background: var(--paper-2); }

.page-about .about-chapter--dark,
.page-about .about-chapter--brown {
  background: var(--ink-950);
  color: var(--white);
}

.page-about .about-chapter--dark .about-chapter__title,
.page-about .about-chapter--brown .about-chapter__title {
  color: var(--white);
}

.page-about .about-chapter__head {
  display: grid;
  gap: 10px;
  margin-bottom: clamp(20px, 3vw, 34px);
}

.page-about .about-chapter__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--blue-deep);
}

.page-about .about-chapter--dark .about-chapter__num,
.page-about .about-chapter--brown .about-chapter__num {
  color: var(--lime);
}

.page-about .about-chapter__title {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(1.4rem, 3.1vw, 2.25rem);
  line-height: 1.22;
  letter-spacing: -0.02em;
  max-width: 26ch;
}

.page-about .about-chapter__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 3vw, 36px);
  align-items: start;
}

.page-about .about-prose p {
  margin: 0 0 1em;
  font-size: 1rem;
  line-height: 1.85;
}

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

.page-about .about-chapter--dark .about-prose p,
.page-about .about-chapter--brown .about-prose p {
  color: var(--paper-2);
}

/* ---------- 图像容器 ---------- */
.page-about .about-fig {
  margin: 0;
  background: var(--ink-900);
  border: var(--line) solid var(--ink-950);
  box-shadow: var(--shadow-hard);
}

.page-about .about-chapter--dark .about-fig,
.page-about .about-chapter--brown .about-fig {
  box-shadow: var(--shadow-blue);
}

.page-about .about-fig img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-fig .media-frame__cap {
  display: block;
  padding: 9px 12px;
  background: var(--ink-900);
  color: var(--paper-2);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  border-top: var(--line) solid var(--ink-950);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 0;
}

.page-about .about-timeline__item {
  position: relative;
  padding: 20px 18px 24px 0;
  border-top: 3px solid rgba(245, 239, 226, 0.22);
  transition: background var(--t-fast) var(--ease),
              transform var(--t-fast) var(--ease);
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  top: -3px;
  left: 0;
  width: 36px;
  height: 3px;
  background: var(--lime);
}

.page-about .about-timeline__item:hover,
.page-about .about-timeline__item:focus-within {
  background: rgba(47, 123, 255, 0.14);
  transform: translateY(-2px);
}

.page-about .about-timeline__season {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .about-timeline__name {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-timeline__text {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--paper-2);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: clamp(18px, 2.6vw, 28px);
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(104px, 1fr));
  gap: 0;
  margin: 0;
  border: var(--line) solid var(--ink-950);
  background: var(--white);
}

.page-about .about-stat {
  padding: 12px 12px 14px;
  border-right: var(--line) solid var(--ink-950);
  border-bottom: var(--line) solid var(--ink-950);
}

.page-about .about-stat__label {
  margin: 0 0 5px;
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--ink-900);
  opacity: 0.72;
}

.page-about .about-stat__num {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.16rem;
  color: var(--blue-deep);
  font-variant-numeric: tabular-nums;
}

/* ---------- 归档 ---------- */
.page-about .about-archive {
  display: grid;
  gap: clamp(20px, 3vw, 32px);
}

.page-about .about-archive__intro {
  max-width: 72ch;
}

.page-about .about-fig--wide {
  width: 100%;
}

.page-about .about-files {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(212px, 1fr));
  gap: 18px;
}

.page-about .about-file {
  background: var(--white);
  border: var(--line) solid var(--ink-950);
  box-shadow: var(--shadow-hard);
  padding: 16px 16px 14px;
  transition: transform var(--t-fast) var(--ease),
              box-shadow var(--t-fast) var(--ease);
}

.page-about .about-file:hover,
.page-about .about-file:focus-within {
  transform: translate(-2px, -4px);
  box-shadow: 8px 10px 0 var(--blue);
}

.page-about .about-file .tag {
  display: inline-block;
  margin-bottom: 12px;
  transform: rotate(-2deg);
}

.page-about .about-file__title {
  margin: 0 0 12px;
  font-size: 1.02rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink-950);
}

.page-about .about-file__meta {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  margin: 0;
  padding: 6px 0;
  border-top: 1px solid var(--paper-2);
  font-family: var(--font-mono);
  font-size: 0.76rem;
}

.page-about .about-file__k { color: var(--gray); }
.page-about .about-file__v { color: var(--ink-900); font-weight: 700; }

.page-about .about-archive__more {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 4px 0 0;
}

/* ---------- 承诺清单 ---------- */
.page-about .about-commit {
  margin: 0;
  display: grid;
  gap: 0;
  border-top: var(--line) solid var(--about-edge);
}

.page-about .about-commit__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: 16px 0;
  border-bottom: var(--line) solid var(--about-edge);
}

.page-about .about-commit__k {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--lime);
}

.page-about .about-commit__v {
  margin: 0;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--paper-2);
}

/* ---------- 合作 ---------- */
.page-about .about-partner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  border: var(--line) solid var(--ink-950);
  background: var(--white);
}

.page-about .about-partner__stat {
  padding: 18px 18px 20px;
  border-bottom: var(--line) solid var(--ink-950);
}

.page-about .about-partner__stat--honor {
  background: var(--ink-950);
  border-bottom: 0;
}

.page-about .about-partner__stat--honor .about-partner__label {
  color: var(--paper-2);
}

.page-about .about-partner__num {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.35rem, 3vw, 1.85rem);
  letter-spacing: -0.01em;
  color: var(--blue-deep);
  font-variant-numeric: tabular-nums;
}

.page-about .about-partner__stat--honor .about-partner__num {
  color: var(--lime);
}

.page-about .about-partner__label {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--ink-900);
}

.page-about .about-partner__note {
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  max-width: 68ch;
  font-size: 1rem;
  line-height: 1.85;
}

/* ---------- 联系入口 ---------- */
.page-about .about-gate {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .about-gate__card {
  display: grid;
  gap: 8px;
  padding: 20px 18px 18px;
  background: var(--white);
  border: var(--line) solid var(--ink-950);
  box-shadow: var(--shadow-hard);
  color: var(--ink-900);
  text-decoration: none;
  transition: transform var(--t-fast) var(--ease),
              box-shadow var(--t-fast) var(--ease);
}

.page-about .about-gate__card:hover,
.page-about .about-gate__card:focus-visible {
  transform: translate(-2px, -4px);
  box-shadow: 8px 10px 0 var(--lime);
}

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

.page-about .about-gate__num {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--blue-deep);
}

.page-about .about-gate__title {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 1.35rem;
  letter-spacing: -0.02em;
}

.page-about .about-gate__desc {
  font-size: 0.94rem;
  line-height: 1.75;
  color: var(--ink-900);
}

.page-about .about-gate__go {
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--blue-deep);
}

.page-about .about-contact-line {
  margin: 20px 0 0;
  font-size: 0.94rem;
  line-height: 1.8;
}

.page-about .about-contact-line .mono {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--blue-deep);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-hero__stat {
    border-right: var(--line) solid var(--about-edge);
    border-bottom: 0;
  }

  .page-about .about-hero__stat:nth-child(2n) {
    border-right: var(--line) solid var(--about-edge);
  }

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

  .page-about .about-commit__row {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: 20px;
    align-items: baseline;
  }

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

  .page-about .about-partner__stat {
    border-right: var(--line) solid var(--ink-950);
  }

  .page-about .about-partner__stat:nth-child(2n) {
    border-right: 0;
  }

  .page-about .about-partner__stat:nth-child(-n + 2) {
    border-bottom: var(--line) solid var(--ink-950);
  }

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

@media (min-width: 960px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
  }

  .page-about .about-rail {
    position: sticky;
    top: var(--header-h);
    align-self: start;
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    border-right: var(--line) solid var(--ink-950);
    border-bottom: 0;
    padding: 26px 16px 24px;
  }

  .page-about .about-rail__list {
    grid-template-columns: 1fr;
    gap: 2px;
  }

  .page-about .about-chapter {
    padding-left: clamp(26px, 4vw, 58px);
    padding-right: clamp(26px, 4vw, 58px);
  }

  .page-about .about-chapter__grid--split {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    gap: clamp(26px, 4vw, 52px);
  }

  .page-about .about-prose {
    max-width: 68ch;
  }
}

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

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

  .page-about .about-partner__stat {
    border-bottom: 0;
  }

  .page-about .about-partner__stat:nth-child(3) {
    border-right: var(--line) solid var(--ink-950);
  }

  .page-about .about-partner__stat:nth-child(-n + 2) {
    border-bottom: 0;
  }

  .page-about .about-partner__stat--honor {
    border-right: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__dot {
    animation: none;
  }

  .page-about .about-rail__link,
  .page-about .about-timeline__item,
  .page-about .about-file,
  .page-about .about-gate__card {
    transition: none;
  }
}
</