.page-about {
  display: block;
}

.page-about .breadcrumb {
  padding-top: clamp(18px, 3vw, 28px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(22px, 4vw, 42px) clamp(28px, 4vw, 48px);
}

.page-about .about-hero .eyebrow {
  margin: 0;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-hero h1 {
  margin: 12px 0 0;
  max-width: 20ch;
  font-size: clamp(30px, 5.4vw, 54px);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-hero .lede {
  margin: clamp(16px, 2.4vw, 26px) 0 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(26px, 4vw, 44px);
  border: 1px solid var(--grid);
  background: var(--grid);
}

@media (min-width: 780px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-fact {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px 16px 20px;
  background: var(--ink-2);
}

.page-about .about-fact-num {
  font-family: var(--mono);
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
}

.page-about .about-fact-label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--mute);
}

/* ---------- 侧栏与内容两栏 ---------- */
.page-about .with-rail {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 36px);
  align-items: start;
}

@media (min-width: 1000px) {
  .page-about .with-rail {
    grid-template-columns: minmax(150px, 190px) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
  }
}

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

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

@media (min-width: 1000px) {
  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 96px;
    align-self: start;
  }
}

.page-about .about-rail .rail-title {
  margin: 0 0 14px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--mute);
}

.page-about .about-rail .rail-nav {
  display: flex;
  flex-direction: column;
}

.page-about .about-rail .rail-link {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 9px 0 9px 12px;
  border-left: 2px solid transparent;
  font-size: 14px;
  line-height: 1.4;
  color: var(--mute);
  text-decoration: none;
  transition: color var(--step), border-color var(--step);
}

.page-about .about-rail .rail-link:hover,
.page-about .about-rail .rail-link.is-active {
  color: var(--paper);
  border-left-color: var(--cyan);
}

.page-about .about-rail .rail-link-idx {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--grid);
  transition: color var(--step);
}

.page-about .about-rail .rail-link.is-active .rail-link-idx {
  color: var(--cyan);
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  padding-block: clamp(30px, 4.6vw, 52px);
  border-top: 1px solid var(--grid);
  scroll-margin-top: clamp(80px, 10vh, 120px);
}

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

.page-about .about-sec .section-title {
  color: var(--paper);
}

.page-about .about-sec .section-num {
  font-family: var(--mono);
  color: var(--orange);
}

.page-about .about-sec .section-note {
  color: var(--mute);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  position: relative;
  margin: clamp(24px, 3.4vw, 36px) 0 0;
  padding: 0 0 0 30px;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--grid);
}

.page-about .tl-item {
  position: relative;
  padding-bottom: clamp(26px, 3.4vw, 40px);
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 6px;
  width: 11px;
  height: 11px;
  background: var(--ink);
  border: 1px solid var(--cyan);
  transition: background var(--step), transform var(--step);
}

.page-about .tl-item:hover::before {
  background: var(--cyan);
  transform: scale(1.15);
}

.page-about .tl-year {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .tl-title {
  margin: 8px 0 8px;
  font-size: clamp(17px, 2.1vw, 21px);
  font-weight: 800;
  line-height: 1.35;
  color: var(--paper);
}

.page-about .tl-text {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mute);
}

.page-about .tl-media {
  display: none;
}

@media (min-width: 820px) {
  .page-about .tl-media {
    display: block;
    max-width: 560px;
    margin-top: 18px;
  }
}

/* ---------- 团队三栏 ---------- */
.page-about .crew {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(24px, 3.4vw, 34px);
  border: 1px solid var(--grid);
  background: var(--grid);
}

@media (min-width: 800px) {
  .page-about .crew {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .crew-item {
  padding: 24px 20px 26px;
  background: var(--ink-2);
  transition: background var(--step);
}

.page-about .crew-item:hover {
  background: var(--panel-a);
}

.page-about .crew-num {
  display: block;
  font-family: var(--mono);
  font-size: clamp(34px, 4vw, 44px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--orange);
}

.page-about .crew-role {
  margin: 14px 0 4px;
  font-size: 17px;
  font-weight: 800;
  color: var(--paper);
}

.page-about .crew-where {
  margin: 0;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mute);
}

.page-about .crew-duties {
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .crew-duties li {
  position: relative;
  padding-left: 15px;
  font-size: 14px;
  line-height: 1.72;
  color: var(--mute);
}

.page-about .crew-duties li + li {
  margin-top: 6px;
}

.page-about .crew-duties li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 6px;
  height: 1px;
  background: var(--cyan);
}

.page-about .about-crew-media {
  margin: clamp(24px, 3.4vw, 34px) 0 0;
}

/* ---------- 流程 ---------- */
.page-about .flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin: clamp(24px, 3.4vw, 34px) 0 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 940px) {
  .page-about .flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0;
  }
}

.page-about .flow-step {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 20px 18px 22px;
  border: 1px solid var(--grid);
  background: var(--ink-2);
  transition: border-color var(--step), transform var(--step);
}

.page-about .flow-step:hover {
  border-color: var(--cyan);
}

@media (min-width: 940px) {
  .page-about .flow-step {
    border-right: 0;
  }

  .page-about .flow-step:last-child {
    border-right: 1px solid var(--grid);
  }

  .page-about .flow-step::after {
    content: "";
    position: absolute;
    right: -5px;
    top: 50%;
    z-index: 2;
    width: 9px;
    height: 9px;
    margin-top: -5px;
    background: var(--ink);
    border-top: 1px solid var(--grid);
    border-right: 1px solid var(--grid);
    transform: rotate(45deg);
  }

  .page-about .flow-step:last-child::after {
    display: none;
  }
}

.page-about .flow-num {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--mute);
}

.page-about .flow-title {
  margin: 12px 0 8px;
  font-size: 17px;
  font-weight: 800;
  color: var(--paper);
}

.page-about .flow-text {
  margin: 0 0 16px;
  flex: 1 1 auto;
  font-size: 14px;
  line-height: 1.72;
  color: var(--mute);
}

.page-about .flow-time {
  align-self: flex-start;
  padding: 4px 9px;
  font-family: var(--mono);
  font-size: 11.5px;
  line-height: 1.4;
  color: var(--ink);
  background: var(--cyan);
}

.page-about .about-flow-media {
  margin: clamp(24px, 3.4vw, 34px) 0 0;
}

/* ---------- 长期做法 ---------- */
.page-about .pledge {
  margin-top: clamp(20px, 3vw, 30px);
  border-top: 1px solid var(--grid);
}

.page-about .pledge-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 0 14px;
  padding: 22px 0;
  border-bottom: 1px solid var(--grid);
}

@media (min-width: 700px) {
  .page-about .pledge-item {
    grid-template-columns: 64px minmax(0, 1fr);
    gap: 0 24px;
  }
}

.page-about .pledge-idx {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--orange);
  padding-top: 3px;
}

.page-about .pledge-body {
  min-width: 0;
}

.page-about .pledge-title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 800;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .pledge-text {
  margin: 0;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.82;
  color: var(--mute);
}

/* ---------- 合作 ---------- */
.page-about .partner-strip {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(22px, 3vw, 32px);
  border: 1px solid var(--grid);
  background: linear-gradient(180deg, var(--panel-a), var(--ink));
}

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

.page-about .partner-cell {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 22px 20px;
  background: transparent;
  border-bottom: 1px solid var(--grid);
}

@media (min-width: 760px) {
  .page-about .partner-cell {
    border-bottom: 0;
    border-right: 1px solid var(--grid);
  }

  .page-about .partner-cell:last-child {
    border-right: 0;
  }
}

.page-about .partner-strip .partner-cell:last-child {
  border-bottom: 0;
}

.page-about .partner-num {
  font-family: var(--mono);
  font-size: clamp(30px, 3.6vw, 42px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--cyan);
}

.page-about .partner-label {
  font-size: 14px;
  line-height: 1.5;
  color: var(--paper);
}

.page-about .partner-strip + .prose {
  margin-top: clamp(22px, 3vw, 30px);
}

/* ---------- 延伸入口 ---------- */
.page-about .next-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: clamp(20px, 3vw, 30px);
  border: 1px solid var(--grid);
  background: var(--grid);
}

@media (min-width: 620px) {
  .page-about .next-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .next-link {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px 22px;
  background: var(--ink);
  text-decoration: none;
  transition: background var(--step), transform var(--step);
}

.page-about .next-link:hover {
  background: var(--ink-2);
  transform: translateY(-2px);
}

.page-about .next-kicker {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--orange);
}

.page-about .next-title {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--paper);
}

.page-about .next-link:hover .next-title {
  color: var(--cyan);
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .tl-item::before,
  .page-about .crew-item,
  .page-about .flow-step,
  .page-about .next-link,
  .page-about .about-rail .rail-link {
    transition: none;
  }

  .page-about .next-link:hover {
    transform: none;
  }
}