.page-about {
  --about-axis: 56px;
  --about-cut: 18px;
  display: block;
  color: var(--paper);
}

.page-about [id] {
  scroll-margin-top: 132px;
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  padding-top: clamp(18px, 3vw, 28px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  padding: clamp(30px, 5vw, 62px) 0 clamp(28px, 4vw, 46px);
  background:
    radial-gradient(120% 140% at 88% -10%, rgba(47, 243, 208, 0.13), transparent 60%),
    linear-gradient(180deg, var(--panel) 0%, var(--ink) 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -20%;
  right: -12%;
  width: 62%;
  height: 140%;
  background: repeating-linear-gradient(
    115deg,
    rgba(47, 243, 208, 0.07) 0 1px,
    transparent 1px 26px
  );
  pointer-events: none;
}

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

.page-about .about-hero__kicker {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gold);
  border: 1px solid var(--line-gold);
  padding: 5px 12px;
  clip-path: polygon(
    9px 0,
    100% 0,
    100% calc(100% - 9px),
    calc(100% - 9px) 100%,
    0 100%,
    0 9px
  );
}

.page-about .about-hero__title {
  margin: clamp(16px, 2.4vw, 24px) 0 clamp(14px, 2vw, 20px);
  font-size: var(--fs-xxl);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.1;
  color: var(--paper);
  max-width: 22ch;
}

.page-about .about-hero__lead {
  max-width: 64ch;
  font-size: var(--fs-md);
  line-height: 1.78;
  color: var(--muted);
  margin: 0;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  margin-top: clamp(26px, 4vw, 44px);
  border: 1px solid var(--line);
  background: var(--line);
}

.page-about .hero-stat {
  background: var(--ink);
  padding: 18px 18px 16px;
}

.page-about .hero-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.45rem, 3.2vw, 1.95rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--cyan);
  line-height: 1.1;
}

.page-about .hero-stat__label {
  display: block;
  margin-top: 6px;
  font-size: var(--fs-sm);
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 首屏锚点图 ---------- */
.page-about .about-anchor {
  position: relative;
  margin: 0;
  overflow: hidden;
  background: var(--charcoal);
  border-bottom: 1px solid var(--line);
  aspect-ratio: 4 / 3;
}

.page-about .about-anchor img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
  opacity: 0.84;
}

.page-about .about-anchor figcaption {
  position: absolute;
  left: var(--gutter);
  right: var(--gutter);
  bottom: 14px;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  line-height: 1.7;
  letter-spacing: 0.03em;
  color: var(--paper);
  text-shadow: 0 1px 10px rgba(6, 20, 16, 0.95);
}

@media (min-width: 760px) {
  .page-about .about-anchor {
    aspect-ratio: 21 / 9;
  }
  .page-about .about-anchor figcaption {
    bottom: 20px;
  }
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 48px);
  padding: clamp(40px, 7vw, 88px) 0 clamp(48px, 8vw, 96px);
}

.page-about .about-rail {
  display: none;
}

.page-about .about-rail__title {
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.14em;
  color: var(--muted);
  margin: 0 0 12px;
}

.page-about .about-rail .index-rail__link {
  display: block;
  padding: 8px 0 8px 14px;
  border-left: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.04em;
  color: var(--muted);
  text-decoration: none;
  transition: color 0.22s var(--ease), border-color 0.22s var(--ease),
    background 0.22s var(--ease);
}

.page-about .about-rail .index-rail__link:hover,
.page-about .about-rail .index-rail__link:focus-visible {
  color: var(--cyan-soft);
  border-left-color: var(--cyan-soft);
}

.page-about .about-rail .index-rail__link[aria-current="true"] {
  color: var(--cyan);
  border-left-color: var(--cyan);
  background: linear-gradient(
    90deg,
    rgba(47, 243, 208, 0.12),
    transparent 80%
  );
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: 180px minmax(0, 1fr);
    gap: clamp(36px, 5vw, 72px);
  }
  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 138px;
    align-self: start;
  }
}

/* ---------- 时间轴阶段 ---------- */
.page-about .stage {
  display: grid;
  grid-template-columns: var(--about-axis) minmax(0, 1fr);
  gap: clamp(12px, 2vw, 22px);
  padding-bottom: clamp(38px, 6vw, 72px);
}

.page-about .stage__marker {
  position: relative;
  padding-top: 3px;
}

.page-about .stage__marker::after {
  content: "";
  position: absolute;
  left: 7px;
  top: 0;
  bottom: calc(-1 * clamp(38px, 6vw, 72px));
  width: 1px;
  background: var(--line-soft);
}

.page-about .stage:last-of-type .stage__marker::after {
  bottom: 0;
}

.page-about .stage__marker::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 9px;
  width: 9px;
  height: 9px;
  background: var(--gold);
  transform: rotate(45deg);
  z-index: 1;
}

.page-about .stage__index {
  display: block;
  margin-left: 22px;
  font-family: var(--font-mono);
  font-size: 0.9375rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

.page-about .stage__content {
  min-width: 0;
}

.page-about .stage__head {
  margin-bottom: 12px;
}

.page-about .ver-badge {
  position: relative;
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.08em;
  color: var(--gold);
  border: 1px solid var(--line-gold);
  padding: 4px 12px;
  background: rgba(232, 185, 74, 0.06);
  clip-path: polygon(
    8px 0,
    100% 0,
    100% calc(100% - 8px),
    calc(100% - 8px) 100%,
    0 100%,
    0 8px
  );
}

.page-about .ver-badge::after {
  content: attr(data-brief);
  position: absolute;
  left: 0;
  top: calc(100% + 10px);
  width: max-content;
  max-width: min(280px, 70vw);
  padding: 9px 13px;
  background: var(--panel-2);
  border-left: 2px solid var(--gold);
  color: var(--paper);
  font-family: var(--font-sans);
  font-size: var(--fs-sm);
  letter-spacing: 0;
  line-height: 1.65;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-4px);
  transition: opacity 0.22s var(--ease), transform 0.22s var(--ease),
    visibility 0.22s;
  z-index: 6;
  pointer-events: none;
}

.page-about .ver-badge:hover::after,
.page-about .ver-badge:focus-visible::after {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.page-about .stage__title,
.page-about .about-section__title {
  margin: 0 0 14px;
  font-size: var(--fs-xl);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.22;
  color: var(--paper);
}

.page-about .stage__title {
  max-width: 26ch;
}

.page-about .stage__text {
  margin: 0;
  max-width: 68ch;
  font-size: var(--fs-base);
  line-height: 1.8;
  color: var(--paper);
}

/* 阶段折叠 */
.page-about .stage__more {
  margin-top: 20px;
  border-top: 1px dashed var(--line-soft);
  max-width: 68ch;
}

.page-about .stage__more > summary {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 0 4px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.06em;
  color: var(--cyan);
  transition: color 0.2s var(--ease);
}

.page-about .stage__more > summary::-webkit-details-marker {
  display: none;
}

.page-about .stage__more > summary::before {
  content: "＋";
  font-size: 0.85em;
  color: var(--cyan-soft);
}

.page-about .stage__more[open] > summary::before {
  content: "－";
}

.page-about .stage__more > summary:hover {
  color: var(--cyan-soft);
}

.page-about .stage__more ul {
  margin: 8px 0 0;
  padding-left: 18px;
  display: grid;
  gap: 7px;
}

.page-about .stage__more li {
  font-size: var(--fs-sm);
  line-height: 1.75;
  color: var(--muted);
}

.page-about .stage__more li::marker {
  color: var(--cyan);
}

/* 阶段内双栏对照 */
.page-about .stage__compare {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 20px;
  border: 1px solid var(--line-soft);
  background: var(--line-soft);
  max-width: 68ch;
}

@media (min-width: 560px) {
  .page-about .stage__compare {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .stage__compare .compare__col {
  background: var(--panel);
  padding: 14px 16px;
}

.page-about .stage__compare .compare__title {
  margin: 0 0 7px;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.1em;
  color: var(--gold);
}

.page-about .stage__compare .stage__compare-text {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.75;
  color: var(--muted);
}

/* 阶段错位 */
@media (min-width: 1024px) {
  .page-about .stage--shift .stage__content {
    margin-left: clamp(24px, 6vw, 86px);
  }
  .page-about .stage__marker::after {
    left: 9px;
  }
  .page-about .stage__marker::before {
    left: 5px;
  }
  .page-about .stage__index {
    margin-left: 28px;
    font-size: 1.0625rem;
  }
}

@media (min-width: 900px) {
  .page-about {
    --about-axis: 78px;
  }
}

/* ---------- 通用章节 ---------- */
.page-about .about-section {
  padding-bottom: clamp(38px, 6vw, 72px);
}

.page-about .about-section__head {
  max-width: 68ch;
  margin-bottom: clamp(22px, 3.4vw, 34px);
}

.page-about .about-section__index {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-section__index::after {
  content: "";
  display: inline-block;
  width: 42px;
  height: 1px;
  margin-left: 12px;
  vertical-align: 4px;
  background: var(--line);
}

.page-about .about-section__title {
  margin-bottom: 12px;
}

.page-about .about-section__lead {
  margin: 0;
  font-size: var(--fs-base);
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 团队 ---------- */
.page-about .crew {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  border: 1px solid var(--line-soft);
  background: var(--line-soft);
  margin-top: clamp(22px, 3.4vw, 34px);
}

@media (min-width: 860px) {
  .page-about .crew {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .crew__item {
  background: var(--panel);
  padding: clamp(20px, 2.8vw, 30px);
  border-left: 2px solid transparent;
  transition: background 0.24s var(--ease), border-color 0.24s var(--ease);
}

.page-about .crew__item:hover {
  background: var(--panel-2);
  border-left-color: var(--cyan);
}

.page-about .crew__num {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .crew__name {
  margin: 0 0 10px;
  font-size: var(--fs-lg);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .crew__desc {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 图片块 ---------- */
.page-about .about-figure {
  margin: 0 0 clamp(38px, 6vw, 72px);
  display: grid;
  gap: 10px;
}

.page-about .about-figure__frame {
  position: relative;
  overflow: hidden;
  background: var(--charcoal);
  border: 1px solid var(--line-soft);
  aspect-ratio: 3 / 2;
  clip-path: polygon(
    0 0,
    100% 0,
    100% calc(100% - var(--about-cut)),
    calc(100% - var(--about-cut)) 100%,
    0 100%
  );
}

.page-about .about-figure__frame img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
  opacity: 0.9;
}

.page-about .about-figure .media__caption {
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  line-height: 1.7;
  letter-spacing: 0.03em;
  color: var(--muted);
}

.page-about .about-figure--right {
  margin-left: auto;
  max-width: 760px;
}

/* ---------- 合作生态 ---------- */
.page-about .partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.6vw, 44px);
  align-items: start;
}

@media (min-width: 900px) {
  .page-about .partners {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  }
}

.page-about .partners__list {
  display: grid;
  gap: 1px;
  border-top: 1px solid var(--line-soft);
}

.page-about .partner-line {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(14px, 2.2vw, 24px);
  padding: clamp(18px, 2.6vw, 26px) 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .partner-line__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 4.4vw, 2.6rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
}

.page-about .partner-line__name {
  margin: 0 0 8px;
  font-size: var(--fs-lg);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .partner-line__desc {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-figure--inline {
  margin-bottom: 0;
}

/* ---------- 覆盖规模 ---------- */
.page-about .scale {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(178px, 1fr));
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
  margin-top: clamp(22px, 3.4vw, 34px);
}

.page-about .scale__item {
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: clamp(18px, 2.6vw, 26px);
  background: linear-gradient(
    180deg,
    rgba(14, 42, 34, 0.85) 0%,
    rgba(6, 20, 16, 0.9) 100%
  );
}

.page-about .scale__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.8rem, 4.6vw, 2.5rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
}

.page-about .scale__label {
  margin: 10px 0 6px;
  font-size: var(--fs-base);
  font-weight: 500;
  color: var(--paper);
}

.page-about .scale__note {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.7;
  color: var(--muted);
}

.page-about .scale__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: clamp(20px, 3vw, 28px) 0 0;
}

.page-about .scale__tags .tag {
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.08em;
  color: var(--muted);
  border: 1px solid var(--line-soft);
  padding: 4px 11px;
}

/* ---------- 后续方向 ---------- */
.page-about .next {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  border: 1px solid var(--line-soft);
  background: var(--line-soft);
  margin-top: clamp(22px, 3.4vw, 34px);
}

@media (min-width: 760px) {
  .page-about .next {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .next__item {
  position: relative;
  background: var(--panel);
  padding: clamp(22px, 3vw, 32px) clamp(20px, 2.8vw, 28px)
    calc(clamp(22px, 3vw, 32px) + 6px);
}

.page-about .next__item::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--orange), rgba(255, 107, 61, 0));
  opacity: 0.8;
}

.page-about .next__name {
  margin: 0 0 10px;
  font-size: var(--fs-lg);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .next__desc {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 行动区 ---------- */
.page-about .about-cta {
  display: grid;
  gap: clamp(18px, 2.6vw, 26px);
  padding: clamp(24px, 3.6vw, 38px);
  border: 1px solid var(--line);
  background:
    linear-gradient(135deg, rgba(47, 243, 208, 0.1), transparent 55%),
    var(--panel);
  clip-path: polygon(
    0 0,
    100% 0,
    100% calc(100% - 22px),
    calc(100% - 22px) 100%,
    0 100%
  );
}

@media (min-width: 860px) {
  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: clamp(24px, 4vw, 48px);
  }
}

.page-about .about-cta__text {
  margin: 0;
  font-size: var(--fs-base);
  line-height: 1.8;
  color: var(--paper);
  max-width: 56ch;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
}

.page-about .about-cta__link {
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.06em;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  padding-bottom: 3px;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

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

@media (prefers-reduced-motion: reduce) {
  .page-about .ver-badge::after,
  .page-about .crew__item,
  .page-about .about-rail .index-rail__link,
  .page-about .about-cta__link {
    transition: none;
  }
  .page-about .ver-badge::after {
    transform: none;
  }
}