.page-about {
  --ab-rule: #1D2740;
  --ab-rail: 2px;
  --ab-maxw: 1200px;
  position: relative;
  display: block;
  overflow-x: clip;
}

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

.page-about__crumbs {
  padding-top: 22px;
  padding-bottom: 6px;
}

.page-about .ab-link {
  color: var(--gc-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(55, 214, 208, 0.45);
  padding-bottom: 1px;
  transition: color 0.2s var(--gc-ease), border-color 0.2s var(--gc-ease);
}

.page-about .ab-link:hover,
.page-about .ab-link:focus-visible {
  color: var(--gc-orange);
  border-bottom-color: var(--gc-orange);
}

.page-about .ab-figure {
  margin: 0;
  border: 2px solid var(--ab-rule);
  background: var(--gc-ink-2);
}

.page-about .ab-figure .gc-media__img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-figure .gc-media__cap {
  padding: 12px 16px;
  border-top: 2px solid var(--ab-rule);
  font-size: 13px;
  line-height: 1.7;
  color: var(--gc-dust);
}

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  position: relative;
  padding: clamp(28px, 5vw, 64px) 0 clamp(48px, 8vw, 96px);
  overflow: hidden;
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  top: -32%;
  right: -22%;
  width: min(760px, 92vw);
  aspect-ratio: 1 / 1;
  background: radial-gradient(circle, rgba(108, 76, 241, 0.3), transparent 62%);
  pointer-events: none;
}

.page-about .ab-hero__grid {
  position: relative;
  display: grid;
  gap: clamp(32px, 5vw, 56px);
  grid-template-columns: 1fr;
  align-items: center;
}

.page-about .ab-hero__eyebrow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin: 0 0 20px;
}

.page-about .ab-hero__eyebrow-text {
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--gc-dust-dim);
}

.page-about .ab-hero__title {
  margin: 0;
  font-family: var(--gc-font-display);
  font-weight: 800;
  font-size: clamp(30px, 6vw, 54px);
  line-height: 1.22;
  letter-spacing: 0.03em;
  color: var(--gc-near);
  max-width: 16em;
}

.page-about .ab-hero__lede {
  margin: 22px 0 0;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.85;
  color: var(--gc-dust);
  max-width: 58ch;
}

.page-about .ab-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 20px;
  margin: 34px 0 0;
}

.page-about .ab-fact {
  margin: 0;
  border-top: 2px solid var(--ab-rule);
  padding-top: 12px;
  min-width: 0;
}

.page-about .ab-fact__num {
  font-family: var(--gc-font-mono);
  font-weight: 700;
  font-size: clamp(22px, 2.8vw, 28px);
  line-height: 1.1;
  color: var(--gc-near);
}

.page-about .ab-fact__label {
  margin: 6px 0 0;
  font-size: 13px;
  color: var(--gc-dust);
  letter-spacing: 0.04em;
}

.page-about .ab-fact:nth-child(1) .ab-fact__num {
  color: var(--gc-orange);
}
.page-about .ab-fact:nth-child(2) .ab-fact__num {
  color: var(--gc-cyan);
}
.page-about .ab-fact:nth-child(3) .ab-fact__num {
  color: var(--gc-violet);
}
.page-about .ab-fact:nth-child(4) .ab-fact__num {
  color: var(--gc-near);
}

.page-about .ab-hero__visual {
  position: relative;
  max-width: 560px;
  margin: 0 auto;
  width: 100%;
}

.page-about .ab-orbit {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .ab-orbit__spin {
  transform-origin: 280px 280px;
  animation: ab-spin 28s linear infinite;
}

.page-about .ab-orbit__spin--slow {
  animation-duration: 44s;
  animation-direction: reverse;
}

@keyframes ab-spin {
  to {
    transform: rotate(360deg);
  }
}

/* ---------- 章节通用 ---------- */

.page-about .ab-block {
  position: relative;
  padding: clamp(56px, 9vw, 106px) 0;
  overflow: hidden;
}

.page-about .ab-block__inner {
  position: relative;
  z-index: 1;
}

.page-about .ab-block__title {
  margin: 12px 0 0;
  font-family: var(--gc-font-display);
  font-weight: 800;
  font-size: clamp(25px, 4.2vw, 40px);
  line-height: 1.28;
  letter-spacing: 0.03em;
  color: var(--gc-near);
  max-width: 22em;
}

.page-about .ab-block__lede {
  margin: 16px 0 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--gc-dust);
  max-width: 64ch;
}

/* ---------- 纵向时间轴 ---------- */

.page-about .ab-timeline::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(29, 39, 64, 0.7) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(29, 39, 64, 0.7) 1px, transparent 1px);
  background-size: 88px 88px;
  -webkit-mask-image: radial-gradient(ellipse at 28% 42%, #000 18%, transparent 74%);
  mask-image: radial-gradient(ellipse at 28% 42%, #000 18%, transparent 74%);
  pointer-events: none;
}

.page-about .ab-annot {
  display: none;
}

.page-about .ab-line {
  list-style: none;
  margin: clamp(36px, 6vw, 62px) 0 0;
  padding: 0;
  position: relative;
}

.page-about .ab-line::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(to bottom, var(--gc-orange), var(--gc-violet) 46%, var(--gc-cyan));
  opacity: 0.6;
}

.page-about .ab-line__item {
  position: relative;
  padding-left: 40px;
  padding-bottom: clamp(32px, 5vw, 54px);
}

.page-about .ab-line__item:last-child {
  padding-bottom: 0;
}

.page-about .ab-line__dot {
  position: absolute;
  left: 2px;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--gc-orange);
  box-shadow: 0 0 0 5px rgba(255, 122, 47, 0.15);
}

.page-about .ab-line__body {
  border: 2px solid var(--ab-rule);
  border-left-width: 4px;
  background: rgba(16, 24, 48, 0.62);
  padding: clamp(18px, 2.8vw, 28px);
  transition: border-color 0.25s var(--gc-ease);
}

.page-about .ab-line__item:hover .ab-line__body {
  border-color: rgba(108, 76, 241, 0.75);
}

.page-about .ab-line__year {
  display: block;
  margin: 0 0 8px;
  font-size: clamp(20px, 2.6vw, 27px);
  font-weight: 700;
  letter-spacing: 0.04em;
}

.page-about .ab-line__title {
  margin: 0 0 10px;
  font-family: var(--gc-font-display);
  font-weight: 700;
  font-size: clamp(17px, 2.1vw, 22px);
  line-height: 1.45;
  color: var(--gc-near);
}

.page-about .ab-line__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--gc-dust);
  max-width: 58ch;
}

.page-about .ab-line__link {
  margin: 14px 0 0;
  font-size: 15px;
}

.page-about .ab-line__media {
  margin: 20px 0 0;
  max-width: 300px;
}

/* ---------- 团队分工 ---------- */

.page-about .ab-crew {
  background: var(--gc-ink-2);
  border-top: 2px solid var(--ab-rule);
  border-bottom: 2px solid var(--ab-rule);
}

.page-about .ab-crew__figure {
  margin-top: clamp(28px, 4vw, 44px);
}

.page-about .ab-crew__band {
  display: grid;
  gap: 2px;
  margin-top: clamp(28px, 4vw, 44px);
  background: var(--ab-rule);
  border: 2px solid var(--ab-rule);
  grid-template-columns: 1fr;
}

.page-about .ab-crew__card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(20px, 2.8vw, 28px);
  background: var(--gc-ink-2);
  transition: background 0.25s var(--gc-ease), box-shadow 0.25s var(--gc-ease);
}

.page-about .ab-crew__card:hover,
.page-about .ab-crew__card:focus-within {
  background: #141e3b;
  box-shadow: inset 0 0 0 2px rgba(55, 214, 208, 0.35);
}

.page-about .ab-crew__idx {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--gc-orange);
}

.page-about .ab-crew__name {
  margin: 0;
  font-family: var(--gc-font-display);
  font-size: clamp(17px, 2vw, 20px);
  font-weight: 700;
  color: var(--gc-near);
  line-height: 1.4;
}

.page-about .ab-crew__metric {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.05em;
  color: var(--gc-cyan);
}

.page-about .ab-crew__desc {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--gc-dust);
}

.page-about .ab-crew__duties {
  list-style: none;
  margin: 10px 0 0;
  padding: 0;
  display: grid;
  gap: 7px;
  border-top: 1px solid var(--ab-rule);
  padding-top: 12px;
}

.page-about .ab-crew__duties li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--gc-dust-dim);
  transition: color 0.22s var(--gc-ease);
}

.page-about .ab-crew__duties li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 8px;
  height: 2px;
  background: currentColor;
  opacity: 0.7;
}

.page-about .ab-crew__card:hover .ab-crew__duties li {
  color: var(--gc-dust);
}

.page-about .ab-tree {
  display: block;
  width: 100%;
  height: auto;
  margin-top: clamp(28px, 4vw, 44px);
}

.page-about .ab-crew__tree-cap {
  margin: 14px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--gc-dust-dim);
  max-width: 70ch;
}

/* ---------- 评测方法 ---------- */

.page-about .ab-method__paper {
  margin-top: clamp(28px, 4vw, 44px);
  padding: clamp(20px, 3.4vw, 46px);
}

.page-about .ab-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
  grid-template-columns: 1fr;
  background: rgba(43, 36, 22, 0.35);
  border: 2px solid var(--gc-paper-ink);
}

.page-about .ab-steps__item {
  background: var(--gc-paper);
  padding: clamp(18px, 2.6vw, 26px);
}

.page-about .ab-steps__no {
  display: inline-block;
  margin: 0 0 12px;
  padding: 3px 9px;
  background: var(--gc-paper-ink);
  color: var(--gc-paper);
  font-size: 12px;
  letter-spacing: 0.12em;
}

.page-about .ab-steps__title {
  margin: 0 0 8px;
  font-family: var(--gc-font-display);
  font-size: clamp(17px, 2vw, 20px);
  font-weight: 700;
  color: var(--gc-paper-ink);
  line-height: 1.4;
}

.page-about .ab-steps__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(43, 36, 22, 0.78);
}

.page-about .ab-method__note {
  margin-top: clamp(24px, 3.5vw, 36px);
  padding-top: clamp(18px, 3vw, 28px);
  border-top: 2px solid rgba(43, 36, 22, 0.28);
}

.page-about .ab-method__note-title {
  margin: 0 0 10px;
  font-family: var(--gc-font-display);
  font-size: clamp(16px, 1.9vw, 19px);
  font-weight: 700;
  color: var(--gc-paper-ink);
}

.page-about .ab-method__note-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(43, 36, 22, 0.8);
  max-width: 72ch;
}

.page-about .ab-switch {
  display: grid;
  gap: 16px;
  grid-template-columns: 1fr;
  margin-top: clamp(24px, 3.5vw, 40px);
  padding: clamp(20px, 2.8vw, 30px);
  border: 2px solid var(--ab-rule);
  border-left: 4px solid var(--gc-cyan);
  background: rgba(55, 214, 208, 0.05);
}

.page-about .ab-switch__big {
  margin: 0;
  font-size: clamp(22px, 3.4vw, 32px);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: 0.01em;
}

.page-about .ab-switch__cap {
  margin: 0 0 10px;
  font-size: 14px;
  color: var(--gc-near);
  letter-spacing: 0.03em;
}

.page-about .ab-switch__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 10px;
}

.page-about .ab-switch__list li {
  padding: 4px 12px;
  border: 1px solid var(--ab-rule);
  font-size: 13px;
  color: var(--gc-dust);
}

/* ---------- 固定访问 ---------- */

.page-about .ab-steady {
  background: var(--gc-ink-2);
  border-top: 2px solid var(--ab-rule);
  border-bottom: 2px solid var(--ab-rule);
}

.page-about .ab-steady__rows {
  margin-top: clamp(28px, 4vw, 48px);
}

.page-about .ab-steady__row {
  display: grid;
  gap: 8px;
  grid-template-columns: 1fr;
  padding: clamp(20px, 3vw, 30px) 0;
  border-top: 2px solid var(--ab-rule);
}

.page-about .ab-steady__row:last-child {
  border-bottom: 2px solid var(--ab-rule);
}

.page-about .ab-steady__no {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.16em;
}

.page-about .ab-steady__name {
  margin: 0;
  font-family: var(--gc-font-display);
  font-size: clamp(17px, 2vw, 20px);
  font-weight: 700;
  color: var(--gc-near);
  line-height: 1.4;
}

.page-about .ab-steady__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--gc-dust);
  max-width: 66ch;
}

.page-about .ab-steady__more {
  margin: clamp(26px, 3.5vw, 38px) 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--gc-dust);
}

/* ---------- 本地服务 ---------- */

.page-about .ab-local__grid {
  display: grid;
  gap: clamp(30px, 4.5vw, 56px);
  grid-template-columns: 1fr;
  align-items: start;
}

.page-about .ab-local__facts {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .ab-local__facts li {
  display: grid;
  gap: 6px;
  grid-template-columns: 1fr;
  padding: 14px 0;
  border-bottom: 1px solid var(--ab-rule);
  font-size: 15px;
  line-height: 1.7;
}

.page-about .ab-local__facts li:first-child {
  border-top: 1px solid var(--ab-rule);
}

.page-about .ab-local__key {
  font-family: var(--gc-font-mono);
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--gc-dust-dim);
}

.page-about .ab-local__val {
  color: var(--gc-near);
  word-break: break-word;
}

.page-about .ab-local__val--mono {
  font-family: var(--gc-font-mono);
  font-size: 14.5px;
  letter-spacing: 0.01em;
  color: var(--gc-cyan);
}

.page-about .ab-local__contact {
  margin-top: 28px;
  padding: clamp(18px, 2.8vw, 26px);
  border: 2px solid var(--ab-rule);
  border-left: 4px solid var(--gc-violet);
  background: rgba(108, 76, 241, 0.08);
}

.page-about .ab-local__contact-title {
  margin: 0 0 10px;
  font-family: var(--gc-font-display);
  font-size: clamp(16px, 1.9vw, 19px);
  font-weight: 700;
  color: var(--gc-near);
  line-height: 1.45;
}

.page-about .ab-local__contact-text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--gc-dust);
}

.page-about .ab-local__contact-link {
  margin: 14px 0 0;
  font-size: 15px;
}

.page-about .ab-local__figure {
  margin: 0;
}

/* ---------- 共享 reveal ---------- */

.page-about .gc-reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.45s var(--gc-ease), transform 0.45s var(--gc-ease);
}

.page-about .gc-reveal.is-visible {
  opacity: 1;
  transform: none;
}

.page-about .gc-js-ready .gc-reveal {
  opacity: 1;
  transform: none;
}

/* ---------- 宽屏 ---------- */

@media (min-width: 640px) {
  .page-about .ab-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .ab-local__facts li {
    grid-template-columns: minmax(96px, auto) 1fr;
    gap: 18px;
    align-items: baseline;
  }
}

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

  .page-about .ab-hero__visual {
    margin: 0 0 0 auto;
  }

  .page-about .ab-switch {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr);
    align-items: center;
    gap: 32px;
  }

  .page-about .ab-steady__row {
    grid-template-columns: 72px 210px minmax(0, 1fr);
    gap: 28px;
    align-items: baseline;
  }

  .page-about .ab-local__grid {
    grid-template-columns: 7fr 5fr;
  }
}

@media (min-width: 1080px) {
  .page-about .ab-crew__band {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 1240px) {
  .page-about .ab-annot {
    display: block;
    position: absolute;
    left: max(20px, calc((100vw - var(--gc-maxw, 1200px)) / 2 - 30px));
    top: 0;
    writing-mode: vertical-rl;
    font-family: var(--gc-font-mono);
    font-size: 12px;
    letter-spacing: 0.24em;
    color: var(--gc-dust-dim);
    white-space: nowrap;
    pointer-events: none;
  }
}

@supports (animation-timeline: view()) {
  @media (min-width: 1240px) {
    .page-about .ab-annot {
      animation: ab-annot-tilt linear both;
      animation-timeline: view();
      animation-range: entry 8% exit 92%;
    }
  }
}

@keyframes ab-annot-tilt {
  from {
    transform: rotate(-1.6deg);
  }
  to {
    transform: rotate(1.6deg);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-orbit__spin,
  .page-about .ab-annot {
    animation: none;
  }

  .page-about .gc-reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

.page-about {
  --gc-maxw: var(--ab-maxw);
}