.page-about {
  --about-rule: rgba(141, 162, 192, .18);
  --about-rule-strong: rgba(141, 162, 192, .34);
  --about-index-w: 200px;
  --about-flow-max: 72ch;
  background: var(--bg-ink);
  color: var(--paper);
}

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 36px 0 46px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -22%;
  right: -16%;
  width: min(560px, 76vw);
  height: min(560px, 76vw);
  background: linear-gradient(150deg, var(--glass-strong) 0%, rgba(25, 224, 210, 0) 64%);
  clip-path: polygon(24% 0, 100% 0, 100% 74%, 0 100%);
  transform: rotate(8deg);
  pointer-events: none;
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 30px;
}

.page-about .about-hero__title {
  margin: 12px 0 18px;
  max-width: 17ch;
  color: var(--paper);
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 58ch;
  color: rgba(244, 240, 230, .84);
}

.page-about .about-metrics {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 20px 32px;
}

.page-about .about-metric {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding-left: 14px;
  border-left: 2px solid var(--cyan);
}

.page-about .about-metric__num {
  font-family: var(--font-mono);
  font-size: clamp(24px, 4.6vw, 34px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--paper);
  font-variant-numeric: tabular-nums;
}

.page-about .about-metric__num--signal {
  color: var(--signal);
}

.page-about .about-metric__label {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--steel);
}

.page-about .about-hero__aside {
  position: relative;
  padding: 22px 20px 24px;
  border: 1px solid rgba(25, 224, 210, .28);
  border-radius: var(--r-md);
  background: linear-gradient(160deg, var(--glass) 0%, rgba(16, 31, 66, .74) 72%);
}

.page-about .about-hero__kicker {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--steel);
}

.page-about .about-hero__round {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: clamp(20px, 4vw, 26px);
  font-weight: 700;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-hero__dot {
  flex: none;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(25, 224, 210, .16);
}

.page-about .about-hero__note {
  margin: 0 0 18px;
  font-size: 14px;
  line-height: 1.72;
  color: rgba(244, 240, 230, .7);
}

.page-about .about-hero__facts {
  list-style: none;
  margin: 0;
  padding: 16px 0 0;
  border-top: 1px solid var(--about-rule);
  display: grid;
  gap: 10px;
}

.page-about .about-hero__facts li {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-size: 14px;
  color: var(--steel);
}

.page-about .about-hero__facts .num {
  color: var(--paper);
  font-weight: 600;
}

.page-about .about-canvas {
  padding-top: 34px;
  border-top: 1px solid var(--about-rule);
}

/* ---------- 索引 ---------- */
.page-about .about-index {
  padding: 0 0 16px;
  margin-bottom: 30px;
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-index__title {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--steel);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: none;
}

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

.page-about .about-index__link {
  display: flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
  padding: 8px 13px;
  border: 1px solid var(--about-rule);
  border-radius: 999px;
  font-size: 13px;
  color: var(--steel);
  text-decoration: none;
  transition: color .25s var(--ease), border-color .25s var(--ease), background-color .25s var(--ease);
}

.page-about .about-index__link .num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--cyan);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--paper);
  border-color: rgba(25, 224, 210, .55);
  background-color: rgba(25, 224, 210, .08);
}

.page-about .about-index__totop {
  display: inline-block;
  margin-top: 14px;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--steel);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .about-index__totop:hover,
.page-about .about-index__totop:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  padding: 36px 0 40px;
  border-top: 1px solid var(--about-rule);
  scroll-margin-top: 90px;
}

.page-about .about-flow > .about-sec:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-sec__head {
  max-width: 60ch;
}

.page-about .about-sec__head .index-tag {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--cyan);
}

.page-about .about-sec .section__title {
  margin: 0 0 14px;
  color: var(--paper);
}

.page-about .about-sec .section__lede {
  margin: 0;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--steel);
}

.page-about .about-copy {
  margin-top: 24px;
  display: grid;
  gap: 16px;
  max-width: var(--about-flow-max);
  font-size: 16px;
  line-height: 1.82;
  color: rgba(244, 240, 230, .84);
}

.page-about .about-copy p {
  margin: 0;
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 28px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--r-md);
  border: 1px solid var(--about-rule);
  object-fit: cover;
  background: linear-gradient(135deg, rgba(25, 224, 210, .14), rgba(16, 31, 66, .9));
}

.page-about .about-figure--lead img {
  aspect-ratio: 16 / 9;
}

.page-about .about-figure--square img {
  aspect-ratio: 4 / 3;
}

.page-about .about-figure figcaption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.72;
  color: var(--steel);
}

/* ---------- 覆盖 ---------- */
.page-about .about-split {
  display: grid;
  gap: 24px;
  margin-top: 8px;
}

.page-about .about-split .about-copy {
  margin-top: 16px;
  max-width: none;
}

.page-about .about-split .about-figure {
  margin: 12px 0 0;
}

.page-about .about-coverage {
  display: grid;
  gap: 28px;
  margin-top: 32px;
}

.page-about .about-modules {
  display: grid;
  gap: 22px;
}

.page-about .about-module {
  padding: 2px 0 2px 16px;
  border-left: 2px solid var(--line-soft);
  transition: border-color .3s var(--ease), background-color .3s var(--ease);
}

.page-about .about-module:hover,
.page-about .about-module:focus-within {
  border-left-color: var(--cyan);
  background-color: rgba(25, 224, 210, .05);
}

.page-about .about-module__title {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-module__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(244, 240, 230, .74);
}

.page-about .about-module__meta {
  margin: 8px 0 0;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--steel);
}

.page-about .about-radar {
  margin: 0;
  padding: 22px 20px;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-md);
  background: linear-gradient(165deg, rgba(16, 31, 66, .92), rgba(11, 24, 54, .6));
  display: grid;
  gap: 16px;
  align-content: start;
}

.page-about .about-radar svg {
  display: block;
  width: 100%;
  max-width: 230px;
  height: auto;
  margin: 0 auto;
}

.page-about .about-radar__cap {
  margin: 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--steel);
}

/* ---------- 流程 ---------- */
.page-about .about-steps {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-step {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 14px;
  padding: 20px 10px 20px 4px;
  border-bottom: 1px solid var(--about-rule);
  transition: background-color .3s var(--ease);
}

.page-about .about-step:hover {
  background-color: rgba(25, 224, 210, .05);
}

.page-about .about-step__index {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.2;
  color: rgba(25, 224, 210, .72);
}

.page-about .about-step__title {
  margin: 0 0 6px;
  font-size: 17px;
  color: var(--paper);
}

.page-about .about-step__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(244, 240, 230, .74);
}

/* ---------- 团队 ---------- */
.page-about .about-network {
  display: grid;
  gap: 16px;
  margin-top: 28px;
}

.page-about .about-network__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 18px;
  border-radius: var(--r-md);
  border-left: 3px solid var(--signal);
  background: linear-gradient(150deg, rgba(16, 31, 66, .9), rgba(11, 24, 54, .55));
}

.page-about .about-network__num {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 800;
  line-height: 1;
  color: var(--signal);
  font-variant-numeric: tabular-nums;
}

.page-about .about-network__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(244, 240, 230, .78);
}

/* ---------- 服务对象 ---------- */
.page-about .about-audience {
  display: grid;
  margin-top: 28px;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-audience__row {
  display: grid;
  gap: 8px;
  padding: 20px 0;
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-audience__who {
  margin: 0;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .05em;
  color: var(--cyan);
}

.page-about .about-audience__what {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(244, 240, 230, .8);
}

/* ---------- 里程碑 ---------- */
.page-about .about-yearnav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 22px 0 0;
}

.page-about .about-yearnav a {
  padding: 6px 13px;
  border: 1px solid var(--about-rule);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--steel);
  text-decoration: none;
  transition: color .25s var(--ease), background-color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .about-yearnav a:hover,
.page-about .about-yearnav a:focus-visible {
  color: var(--deep);
  background-color: var(--signal);
  border-color: var(--signal);
}

.page-about .about-timeline {
  list-style: none;
  margin: 28px 0 0;
  padding: 0 0 0 22px;
  border-left: 1px solid var(--about-rule-strong);
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 28px;
  scroll-margin-top: 96px;
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 6px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(25, 224, 210, .16);
}

.page-about .about-timeline__item:last-child::before {
  background: var(--signal);
  box-shadow: 0 0 0 3px rgba(245, 197, 66, .18);
}

.page-about .about-timeline__year {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: .12em;
  color: var(--cyan);
}

.page-about .about-timeline__item:last-child .about-timeline__year {
  color: var(--signal);
}

.page-about .about-timeline__title {
  margin: 0 0 6px;
  font-size: 17px;
  color: var(--paper);
}

.page-about .about-timeline__text {
  margin: 0;
  max-width: 56ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(244, 240, 230, .74);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-sec--next {
  padding-bottom: 12px;
}

.page-about .about-next__title {
  margin: 0 0 10px;
  color: var(--paper);
}

.page-about .about-next__lede {
  margin: 0;
  max-width: 52ch;
  color: var(--steel);
}

.page-about .about-next {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-next a {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 6px 16px;
  padding: 16px 18px;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-sm);
  color: var(--paper);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: border-color .28s var(--ease), background-color .28s var(--ease), transform .28s var(--ease);
}

.page-about .about-next a span {
  font-size: 13.5px;
  font-weight: 400;
  color: var(--steel);
}

.page-about .about-next a:hover,
.page-about .about-next a:focus-visible {
  border-color: rgba(245, 197, 66, .6);
  background-color: rgba(245, 197, 66, .08);
  transform: translateX(4px);
}

/* ---------- 平板 ---------- */
@media (min-width: 640px) {
  .page-about .about-modules {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 30px;
  }

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

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

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 56px 0 64px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 36px;
    align-items: center;
  }

  .page-about .about-split .about-copy {
    margin-top: 0;
  }

  .page-about .about-split .about-figure {
    margin: 0;
  }

  .page-about .about-coverage {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    gap: 36px;
    align-items: start;
  }

  .page-about .about-audience {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 44px;
  }

  .page-about .about-step {
    grid-template-columns: 56px minmax(0, 1fr);
    padding: 22px 14px 22px 6px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-canvas {
    display: grid;
    grid-template-columns: var(--about-index-w) minmax(0, 1fr);
    column-gap: 56px;
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 92px;
    margin: 0;
    padding: 0 0 0 18px;
    border-bottom: 0;
    border-left: 1px solid var(--about-rule-strong);
  }

  .page-about .about-index__list {
    display: grid;
    gap: 2px;
    overflow: visible;
    margin-top: 6px;
  }

  .page-about .about-index__link {
    border: 0;
    border-left: 2px solid transparent;
    border-radius: 0;
    padding: 9px 0 9px 12px;
    justify-content: flex-start;
  }

  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible {
    color: var(--paper);
    border-left-color: var(--cyan);
    background-color: transparent;
  }

  .page-about .about-index__totop {
    margin-top: 18px;
  }

  .page-about .about-timeline__text {
    font-size: 15px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: .01ms !important;
    animation-duration: .01ms !important;
  }
}