.page-about {
  --about-rail-x: 22px;
  --about-step: 0px;
  color: var(--ink);
  background: var(--paper);
  overflow-x: hidden;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.01em;
  line-height: 1.12;
  color: inherit;
}

.page-about p {
  margin: 0 0 1em;
  line-height: 1.75;
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(28px, 5vw, 44px) 0 clamp(72px, 11vw, 128px);
  background:
    linear-gradient(135deg, rgba(11, 42, 31, .96), var(--indigo) 92%),
    var(--deep);
  color: var(--paper);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--grid-light) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid-light) 1px, transparent 1px);
  background-size: 24px 24px;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: clamp(28px, 5vw, 56px);
  background: var(--paper);
  clip-path: polygon(0 100%, 100% 0, 100% 100%);
}

.page-about .about-hero .container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__crumb {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: clamp(28px, 5vw, 52px);
  color: var(--slate);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
}

.page-about .about-hero__crumb .breadcrumb__item {
  color: inherit;
  text-decoration: none;
}

.page-about .about-hero__crumb .breadcrumb__item[aria-current="page"] {
  color: var(--paper);
}

.page-about .about-hero__crumb-sep {
  color: var(--line-strong);
}

.page-about .about-hero__layout {
  display: grid;
  gap: clamp(28px, 5vw, 56px);
}

.page-about .about-hero__title {
  font-size: clamp(30px, 6.4vw, 68px);
  line-height: 1.04;
  margin-top: 14px;
  padding-bottom: 18px;
  border-bottom: 2px solid var(--grass-bright);
}

.page-about .about-hero__lead {
  font-size: clamp(15px, 1.6vw, 17px);
  color: rgba(234, 243, 236, .84);
  max-width: 58ch;
}

.page-about .about-hero__fixtures {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.page-about .about-hero__fixture {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 13px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-hero__fixture-key {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--slate);
}

.page-about .about-hero__fixture-value {
  font-size: 20px;
  font-weight: 700;
  color: var(--grass-bright);
}

/* ---------- 起点 ---------- */
.page-about .about-origin {
  padding: clamp(48px, 8vw, 96px) 0;
  background: var(--paper);
}

.page-about .about-origin__grid {
  display: grid;
  gap: clamp(24px, 4vw, 56px);
}

.page-about .about-origin__title {
  font-size: clamp(24px, 3.6vw, 40px);
  margin-top: 14px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--grass);
}

.page-about .about-origin__body {
  font-size: 16px;
  color: #2b3a33;
  max-width: 62ch;
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  padding: clamp(48px, 8vw, 104px) 0;
  background: var(--deep);
  color: var(--paper);
  overflow: hidden;
}

.page-about .about-timeline__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .16;
  filter: saturate(.7);
  pointer-events: none;
}

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

.page-about .about-timeline .chapter-head__title {
  color: var(--paper);
}

.page-about .about-timeline .chapter-head__note {
  color: var(--slate);
  font-size: 14px;
  max-width: 56ch;
}

.page-about .about-rail {
  list-style: none;
  margin: clamp(32px, 5vw, 56px) 0 0;
  padding: 0;
  position: relative;
}

.page-about .about-rail::before {
  content: '';
  position: absolute;
  left: var(--about-rail-x);
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--grass-bright), var(--grass) 45%, rgba(124, 147, 168, .18));
}

.page-about .about-rail__item {
  position: relative;
  padding: 0 0 clamp(30px, 4vw, 46px) calc(var(--about-rail-x) + 34px);
  --about-step: 0px;
}

.page-about .about-rail__item::before {
  content: '';
  position: absolute;
  left: calc(var(--about-rail-x) - 4px);
  top: 9px;
  width: 9px;
  height: 9px;
  background: var(--grass-bright);
  box-shadow: 0 0 0 4px rgba(52, 196, 107, .14);
}

.page-about .about-rail__year {
  display: block;
  font-size: clamp(20px, 2.6vw, 28px);
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--lamp);
  margin-bottom: 6px;
}

.page-about .about-rail__title {
  font-size: clamp(17px, 2vw, 21px);
  color: var(--paper);
  margin-bottom: 8px;
}

.page-about .about-rail__body p {
  color: rgba(234, 243, 236, .76);
  font-size: 15px;
  max-width: 56ch;
}

.page-about .about-timeline__tail {
  margin-top: clamp(20px, 3vw, 32px);
  padding-top: 20px;
  border-top: 1px solid var(--line);
  color: var(--slate);
  font-size: 14px;
}

.page-about .about-timeline__tail a {
  color: var(--grass-bright);
  text-decoration: none;
  border-bottom: 1px solid rgba(52, 196, 107, .45);
}

.page-about .about-timeline__tail a:hover,
.page-about .about-timeline__tail a:focus-visible {
  border-bottom-color: var(--grass-bright);
}

/* ---------- 内容生产 ---------- */
.page-about .about-craft {
  padding: clamp(48px, 8vw, 100px) 0;
  background: var(--paper);
}

.page-about .about-craft__layout {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  margin-top: clamp(28px, 4vw, 48px);
}

.page-about .about-craft__steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
  counter-reset: craft;
}

.page-about .about-craft__step {
  padding: 20px 0;
  border-top: 1px solid var(--line-soft);
  display: grid;
  grid-template-columns: 44px 1fr;
  grid-template-areas:
    "no title"
    "no body";
  column-gap: 14px;
}

.page-about .about-craft__step:last-child {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-craft__no {
  grid-area: no;
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--grass);
  padding-top: 3px;
}

.page-about .about-craft__step-title {
  grid-area: title;
  font-size: 18px;
  margin-bottom: 6px;
  color: var(--ink);
}

.page-about .about-craft__step p {
  grid-area: body;
  font-size: 15px;
  color: #37463f;
  max-width: 52ch;
}

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

.page-about .about-craft__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-left: 3px solid var(--grass);
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-coverage {
  padding: clamp(48px, 8vw, 104px) 0;
  background: var(--indigo);
  color: var(--paper);
  position: relative;
}

.page-about .about-coverage::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(234, 243, 236, .05) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(234, 243, 236, .05) 1px, transparent 1px);
  background-size: 24px 24px;
  pointer-events: none;
}

.page-about .about-coverage .container {
  position: relative;
  z-index: 1;
}

.page-about .about-coverage .chapter-head__title {
  color: var(--paper);
}

.page-about .about-coverage__grid {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  margin-top: clamp(28px, 4vw, 44px);
}

.page-about .about-coverage__stats {
  display: grid;
  gap: 0;
  border-top: 1px solid rgba(234, 243, 236, .18);
}

.page-about .about-coverage__stat {
  padding: 20px 0;
  border-bottom: 1px solid rgba(234, 243, 236, .12);
  display: grid;
  grid-template-columns: minmax(0, auto) 1fr;
  align-items: baseline;
  gap: 6px 14px;
}

.page-about .about-coverage__num {
  font-size: clamp(28px, 4.4vw, 40px);
  font-weight: 700;
  color: var(--grass-bright);
  line-height: 1;
}

.page-about .about-coverage__unit {
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--lamp);
  font-family: var(--font-mono);
}

.page-about .about-coverage__stat p {
  grid-column: 1 / -1;
  font-size: 14px;
  color: rgba(234, 243, 236, .74);
  margin: 4px 0 0;
}

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

.page-about .about-coverage__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-top: 2px solid var(--lamp);
}

.page-about .about-coverage__figure .media-frame__caption {
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--slate);
  padding-top: 10px;
  font-family: var(--font-mono);
}

.page-about .about-coverage__chart {
  margin-top: clamp(32px, 5vw, 56px);
  padding-top: clamp(24px, 3vw, 36px);
  border-top: 1px solid rgba(234, 243, 236, .2);
}

.page-about .about-coverage__svg {
  display: block;
  width: 100%;
  height: clamp(100px, 18vw, 160px);
  margin: 14px 0 12px;
}

.page-about .about-coverage__chart-note {
  font-size: 14px;
  color: rgba(234, 243, 236, .72);
  max-width: 62ch;
}

/* ---------- 节奏 ---------- */
.page-about .about-rhythm {
  padding: clamp(48px, 8vw, 100px) 0;
  background: var(--paper);
}

.page-about .about-rhythm__grid {
  display: grid;
  gap: clamp(24px, 3vw, 40px);
  margin-top: clamp(28px, 4vw, 44px);
  align-items: start;
}

.page-about .about-rhythm__block {
  padding: 24px 0 24px 20px;
  border-left: 2px solid var(--grass);
}

.page-about .about-rhythm__block:last-child {
  border-left-color: var(--slate);
}

.page-about .about-rhythm__title {
  font-size: clamp(18px, 2.2vw, 24px);
  margin: 16px 0 12px;
  color: var(--ink);
}

.page-about .about-rhythm__block p {
  font-size: 15px;
  color: #37463f;
  max-width: 52ch;
}

.page-about .about-rhythm__cta {
  margin-top: clamp(32px, 5vw, 52px);
  padding: clamp(20px, 3vw, 32px);
  background: linear-gradient(180deg, rgba(30, 122, 69, .08), transparent);
  border-top: 2px solid var(--grass);
}

.page-about .about-rhythm__cta-text {
  font-size: 15px;
  color: #2b3a33;
  margin-bottom: 16px;
}

.page-about .about-rhythm__cta-btns {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-rhythm__legal {
  margin-top: 28px;
  padding-top: 16px;
  border-top: 1px solid var(--line-soft);
  font-size: 12.5px;
  color: var(--slate);
}

.page-about .about-rhythm__legal .mono {
  color: var(--ink);
}

/* ---------- 桌面 ---------- */
@media (min-width: 600px) {
  .page-about .about-coverage__stat {
    grid-template-columns: 130px 1fr;
    align-items: center;
  }

  .page-about .about-coverage__stat p {
    grid-column: 2 / 3;
  }
}

@media (min-width: 880px) {
  .page-about .about-hero__layout {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: end;
    gap: clamp(32px, 5vw, 72px);
  }

  .page-about .about-origin__grid {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: clamp(32px, 5vw, 72px);
  }

  .page-about .about-craft__layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }

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

  .page-about .about-rhythm__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: clamp(32px, 4vw, 64px);
  }

  .page-about .about-rhythm__block:last-child {
    margin-top: 48px;
  }

  .page-about .about-rail__item:nth-child(1) { padding-left: calc(var(--about-rail-x) + 34px); }
  .page-about .about-rail__item:nth-child(2) { padding-left: calc(var(--about-rail-x) + 44px); }
  .page-about .about-rail__item:nth-child(3) { padding-left: calc(var(--about-rail-x) + 54px); }
  .page-about .about-rail__item:nth-child(4) { padding-left: calc(var(--about-rail-x) + 64px); }
  .page-about .about-rail__item:nth-child(5) { padding-left: calc(var(--about-rail-x) + 74px); }
  .page-about .about-rail__item:nth-child(6) { padding-left: calc(var(--about-rail-x) + 84px); }

  .page-about .about-rail__item {
    display: grid;
    grid-template-columns: 96px minmax(0, 1fr);
    column-gap: 20px;
  }

  .page-about .about-rail__year {
    text-align: right;
    margin-bottom: 0;
    padding-top: 2px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-rail::before {
    transform: skewX(-2.6deg);
    transform-origin: top left;
  }
}