.page-about {
  --about-rail: 2px;
  --about-gap: clamp(24px, 5vw, 48px);
  display: block;
}

/* ---------- 面包屑间距 ---------- */
.page-about .crumbs {
  padding-top: clamp(12px, 3vw, 22px);
  padding-bottom: clamp(10px, 2vw, 16px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding: clamp(20px, 4vw, 38px) 0 clamp(38px, 7vw, 72px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: calc(100% - 26px);
  z-index: -1;
  background:
    radial-gradient(120% 90% at 10% 0%, rgba(37, 227, 196, 0.14), transparent 58%),
    radial-gradient(90% 80% at 95% 100%, rgba(124, 107, 255, 0.12), transparent 62%),
    linear-gradient(140deg, var(--ink-800), var(--ink-900) 62%, var(--panel));
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 34px), 0 100%);
}

.page-about .about-hero__inner {
  display: grid;
  gap: clamp(20px, 4vw, 36px);
}

.page-about .about-hero__eyebrow {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--cyan);
}

.page-about .about-hero h1 {
  margin: 0 0 18px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(28px, 7vw, 52px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--text);
  max-width: 15ch;
}

.page-about .about-hero .lede {
  margin: 0;
  max-width: 52ch;
  color: var(--muted);
  font-size: clamp(16px, 2.2vw, 17px);
  line-height: 1.75;
}

.page-about .about-hero__tags {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-hero__figure {
  margin: 0;
  position: relative;
  border: 1px solid var(--line);
  background: var(--panel);
  overflow: hidden;
  clip-path: polygon(0 22px, 22px 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  filter: saturate(0.85) contrast(1.06);
}

.page-about .about-hero__cap {
  display: block;
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  background: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 章节外壳 ---------- */
.page-about .about-sec {
  position: relative;
  padding: clamp(30px, 6vw, 62px) 0;
  border-top: 1px solid var(--line);
}

.page-about .about-sec:first-of-type {
  border-top: 0;
}

.page-about .about-sec .section-head {
  margin-bottom: clamp(22px, 4vw, 36px);
}

.page-about .about-more {
  margin: clamp(20px, 3vw, 26px) 0 0;
  font-size: 15px;
  color: var(--muted);
  line-height: 1.75;
}

.page-about .about-more .link,
.page-about .rule-box .link {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

.page-about .about-more .link:hover,
.page-about .rule-box .link:hover {
  color: var(--text);
}

.page-about .about-more .link:focus-visible,
.page-about .rule-box .link:focus-visible,
.page-about a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .note {
  margin: clamp(18px, 3vw, 24px) 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--orange);
  color: var(--muted);
  font-size: 14px;
  line-height: 1.75;
}

/* ---------- 01 三条主线 ---------- */
.page-about .tracks {
  display: grid;
  gap: 14px;
}

.page-about .track {
  position: relative;
  padding: 22px 20px 22px 22px;
  border: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(18, 38, 58, 0.92), rgba(10, 23, 38, 0.92));
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .track::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 42px;
  height: 2px;
  background: var(--cyan);
}

.page-about .track__idx {
  display: block;
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--cyan);
  margin-bottom: 8px;
}

.page-about .track__title {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-size: 19px;
  font-weight: 800;
  color: var(--text);
  letter-spacing: -0.01em;
}

.page-about .track__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .about-scale {
  margin-top: clamp(20px, 4vw, 32px);
}

.page-about .about-scale .datacard__value.num {
  font-family: var(--font-mono);
}

/* ---------- 年份分布图 ---------- */
.page-about .archive-chart-wrap {
  margin-top: clamp(24px, 4vw, 36px);
  padding: 18px 18px 12px;
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .archive-chart__cap {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .archive-chart {
  display: block;
  width: 100%;
  height: auto;
  max-height: 140px;
}

/* ---------- 02 团队流程 ---------- */
.page-about .about-team {
  align-items: start;
}

.page-about .about-team__figure {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--panel);
  overflow: hidden;
}

.page-about .about-team__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.8) contrast(1.05);
}

.page-about .about-team__cap,
.page-about .about-evo__cap {
  display: block;
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  background: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .roles {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(230px, 76%);
  gap: 12px;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scroll-snap-type: x mandatory;
  padding-bottom: 8px;
  margin: 0;
}

.page-about .roles::-webkit-scrollbar {
  height: 4px;
}

.page-about .roles::-webkit-scrollbar-thumb {
  background: var(--line);
}

.page-about .role {
  scroll-snap-align: start;
  position: relative;
  padding: 20px 18px;
  border: 1px solid var(--line);
  background: var(--panel);
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
}

.page-about .role::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 16px;
  height: 16px;
  background: var(--cyan);
  clip-path: polygon(0 0, 100% 100%, 100% 0);
}

.page-about .role__badge {
  display: inline-block;
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--muted);
  margin-bottom: 10px;
}

.page-about .role__title {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 800;
  color: var(--text);
}

.page-about .role__count {
  margin: 0 0 12px;
  font-size: 22px;
  color: var(--cyan);
  letter-spacing: 0.02em;
}

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

/* ---------- 03 版本时间轴 ---------- */
.page-about .tl {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 10px;
  width: var(--about-rail);
  background: linear-gradient(180deg, var(--cyan), var(--violet) 55%, var(--line));
}

.page-about .tl__item {
  position: relative;
  padding-left: 34px;
  margin-bottom: 14px;
}

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

.page-about .tl__dot {
  position: absolute;
  left: 0;
  top: 17px;
  width: 13px;
  height: 13px;
  border: 2px solid var(--cyan);
  background: var(--ink-900);
  border-radius: 50%;
  box-sizing: border-box;
}

.page-about .tl__node {
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .tl__summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 12px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .tl__summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--cyan);
}

.page-about .tl__node[open] .tl__summary::after {
  content: "－";
}

.page-about .tl__stage {
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--orange);
}

.page-about .tl__title {
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 800;
  color: var(--text);
}

.page-about .tl__body {
  padding: 0 16px 16px;
  border-top: 1px solid var(--line);
}

.page-about .tl__body p {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-evo__figure {
  margin: clamp(24px, 4vw, 40px) 0 0;
  border: 1px solid var(--line);
  background: var(--panel);
  overflow: hidden;
}

.page-about .about-evo__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.85) contrast(1.06);
}

/* ---------- 04 同步状态带 ---------- */
.page-about .syncband {
  display: grid;
  gap: 16px;
  padding: clamp(18px, 3vw, 26px);
  border: 1px solid var(--line);
  background: linear-gradient(100deg, var(--panel), var(--ink-800) 70%, var(--ink-900));
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%);
}

.page-about .syncband__rail {
  position: relative;
  height: 5px;
  background: var(--ink-900);
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-about .syncband__fill {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 6%;
  background: linear-gradient(90deg, var(--violet), var(--cyan));
}

.page-about .syncband__row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
}

.page-about .syncband__node {
  font-size: 18px;
  color: var(--text);
  letter-spacing: 0.02em;
}

.page-about .syncband__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
  max-width: 70ch;
}

.page-about .syncband__meta {
  margin: 0;
  display: grid;
  gap: 10px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}

.page-about .syncband__meta-row {
  display: grid;
  gap: 4px;
}

.page-about .syncband__meta dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

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

/* ---------- 05 口径与纠错 ---------- */
.page-about .about-rule {
  align-items: start;
}

.page-about .about-rule .prose p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--text);
}

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

.page-about .rule-box {
  padding: 22px 20px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--orange);
  background: var(--ink-800);
}

.page-about .rule-box__title {
  margin: 0 0 12px;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 800;
  color: var(--text);
}

.page-about .rule-box__text {
  margin: 0 0 12px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .rule-box__text:last-child {
  margin-bottom: 0;
}

/* ---------- 中屏 ---------- */
@media (min-width: 720px) {
  .page-about .tracks {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .roles {
    grid-auto-flow: row;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    grid-auto-columns: auto;
    overflow: visible;
    padding-bottom: 0;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
    gap: clamp(30px, 5vw, 58px);
  }

  .page-about .about-hero h1 {
    max-width: 18ch;
  }

  .page-about .about-team {
    align-items: stretch;
  }

  .page-about .about-team__figure {
    align-self: start;
  }

  .page-about .tl::before {
    left: 50%;
    transform: translateX(-50%);
  }

  .page-about .tl__item {
    width: 50%;
    padding-left: 0;
    margin-bottom: 18px;
  }

  .page-about .tl__item:nth-child(odd) {
    padding-right: 42px;
  }

  .page-about .tl__item:nth-child(odd) .tl__summary {
    justify-content: flex-end;
  }

  .page-about .tl__item:nth-child(odd) .tl__summary::after {
    margin-left: 0;
  }

  .page-about .tl__item:nth-child(odd) .tl__dot {
    left: auto;
    right: -7px;
  }

  .page-about .tl__item:nth-child(even) {
    margin-left: 50%;
    padding-left: 42px;
  }

  .page-about .tl__item:nth-child(even) .tl__dot {
    left: -7px;
  }

  .page-about .syncband__meta {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }
}

/* ---------- 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .page-about .roles {
    scroll-snap-type: none;
  }
}
</main>