.page-about {
  --about-hair: rgba(242, 237, 227, 0.1);
  --about-gold-line: rgba(201, 162, 39, 0.4);
  display: block;
  padding-bottom: clamp(48px, 8vw, 96px);
  color: var(--ivory);
}

/* 面包屑 */
.page-about .crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: clamp(20px, 4vw, 34px);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--slate);
}
.page-about .crumbs a {
  color: var(--slate);
  text-decoration: none;
}
.page-about .crumbs a:hover {
  color: var(--gold-lit);
}
.page-about .crumbs span[aria-hidden="true"] {
  color: var(--about-gold-line);
}
.page-about .crumbs span:last-child {
  color: var(--gold);
}

/* 首屏 */
.page-about .about-hero {
  padding-top: clamp(26px, 5vw, 54px);
  padding-bottom: clamp(40px, 6vw, 76px);
}
.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 5vw, 48px);
}
.page-about .about-hero__kicker {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: 0.24em;
  color: var(--gold);
}
.page-about .about-hero h1 {
  max-width: 14ch;
  margin: 0 0 clamp(16px, 2.4vw, 24px);
  font-family: var(--font-display);
  font-size: clamp(40px, 9vw, 74px);
  font-weight: 800;
  line-height: 0.98;
  letter-spacing: -0.02em;
  color: var(--ivory);
}
.page-about .about-hero .lede {
  max-width: 46ch;
  margin: 0 0 clamp(22px, 3vw, 34px);
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--ivory);
  opacity: 0.86;
}
.page-about .about-hero__figures {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 14px;
  margin: 0;
  padding: 18px 0 0;
  list-style: none;
  border-top: 1px solid var(--about-hair);
}
.page-about .about-hero__figures li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--slate);
}
.page-about .about-hero__figures .num {
  font-family: var(--font-mono);
  font-size: 22px;
  line-height: 1.1;
  color: var(--gold);
  letter-spacing: -0.02em;
}
.page-about .about-hero__media {
  margin: 0;
  border-radius: var(--r);
  overflow: hidden;
  border: 1px solid var(--about-hair);
}
.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: end;
    gap: clamp(32px, 4vw, 64px);
  }
}

/* 章节骨架 */
.page-about .about-block {
  border-top: 1px solid var(--about-hair);
  padding: clamp(40px, 6vw, 76px) 0;
}
.page-about .about-block--ink {
  background: var(--ink);
}
.page-about .about-block__inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 3vw, 32px);
}
.page-about .about-block__num {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: clamp(44px, 6vw, 60px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--gold);
}
.page-about .about-block__num::after {
  content: "";
  display: block;
  width: 56px;
  height: 2px;
  margin-top: 12px;
  background: var(--gold);
  opacity: 0.55;
}
.page-about .about-block__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--ivory);
}
.page-about .about-block__main > p {
  max-width: 62ch;
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ivory);
  opacity: 0.9;
}
.page-about .about-block__lead {
  font-size: 17px !important;
  opacity: 1 !important;
}
.page-about .about-block__note {
  font-size: 14px !important;
  color: var(--slate) !important;
  opacity: 1 !important;
}
.page-about .about-inline-link {
  margin: clamp(18px, 2.4vw, 24px) 0 0 !important;
}
.page-about .about-block__figure {
  margin: clamp(22px, 3vw, 34px) 0 0;
  border-radius: var(--r);
  overflow: hidden;
  border: 1px solid var(--about-hair);
}
.page-about .about-block__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
@media (min-width: 960px) {
  .page-about .about-block__inner {
    grid-template-columns: minmax(230px, 300px) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 76px);
    align-items: start;
  }
}

/* 三档权益 */
.page-about .tiers {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin: clamp(22px, 3vw, 30px) 0 clamp(14px, 2vw, 18px);
}
.page-about .tier {
  position: relative;
  padding: clamp(18px, 2.4vw, 26px);
  background: var(--table);
  border: 1px solid var(--edge);
  border-radius: var(--r);
  transition: transform 0.22s ease, border-color 0.22s ease;
}
.page-about .tier::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  right: -1px;
  height: 3px;
  background: var(--tier-accent);
  border-radius: var(--r) var(--r) 0 0;
}
.page-about .tier--bronze {
  --tier-accent: #9a7b4f;
}
.page-about .tier--gold {
  --tier-accent: var(--gold);
}
.page-about .tier--ace {
  --tier-accent: var(--red);
}
.page-about .tier:hover {
  transform: translateY(-4px);
  border-color: var(--tier-accent);
}
.page-about .tier__name {
  margin: 0;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.24em;
  color: var(--tier-accent);
}
.page-about .tier__num {
  margin: 12px 0 6px;
  font-family: var(--font-mono);
  font-size: clamp(34px, 4.6vw, 44px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ivory);
}
.page-about .tier__num .num {
  font-size: inherit;
  color: inherit;
}
.page-about .tier__meta {
  margin: 0 0 16px;
  font-size: 13px;
  color: var(--slate);
}
.page-about .tier__list {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 14px 0 0;
  list-style: none;
  border-top: 1px solid var(--about-hair);
  font-size: 14px;
  line-height: 1.7;
  color: var(--slate);
}
.page-about .tier__list li {
  position: relative;
  padding-left: 16px;
}
.page-about .tier__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--tier-accent);
  opacity: 0.9;
}
.page-about .tiers__note {
  max-width: 60ch;
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--slate);
}
@media (min-width: 820px) {
  .page-about .tiers {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
    gap: clamp(16px, 2.2vw, 26px);
  }
  .page-about .tier:nth-child(1) {
    margin-top: 46px;
  }
  .page-about .tier:nth-child(3) {
    margin-top: 22px;
  }
}

/* 规则六章 */
.page-about .rule-list {
  display: grid;
  gap: 10px;
  margin: clamp(20px, 3vw, 28px) 0 0;
}
.page-about .rule-item {
  border: 1px solid var(--edge);
  border-radius: var(--r);
  background: var(--table);
  overflow: hidden;
}
.page-about .rule-item summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 18px;
  font-size: 15px;
  font-weight: 600;
  color: var(--ivory);
  cursor: pointer;
  list-style: none;
}
.page-about .rule-item summary::-webkit-details-marker {
  display: none;
}
.page-about .rule-item summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--gold);
}
.page-about .rule-item[open] summary::after {
  content: "–";
}
.page-about .rule-item[open] summary {
  border-bottom: 1px solid var(--about-hair);
}
.page-about .rule-item__idx {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--gold);
}
.page-about .rule-item p {
  max-width: 62ch;
  margin: 0;
  padding: 14px 18px 18px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
}

/* 版本时间线 */
.page-about .timeline {
  display: flex;
  gap: clamp(14px, 2vw, 24px);
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 34px 2px 22px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}
.page-about .timeline .tl-node {
  position: relative;
  flex: 0 0 min(258px, 74vw);
  scroll-snap-align: start;
  padding: 24px 0 0;
  border-top: 1px solid var(--about-gold-line);
  transition: border-color 0.2s ease;
}
.page-about .tl-node::before {
  content: "";
  position: absolute;
  top: -5px;
  left: 0;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(201, 162, 39, 0.14);
}
.page-about .tl-node:hover {
  border-top-color: var(--gold-lit);
}
.page-about .tl-node .tl-node__idx {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--gold);
}
.page-about .tl-node h3 {
  margin: 0 0 8px;
  font-family: var(--font-body);
  font-size: 17px;
  font-weight: 700;
  color: var(--ivory);
}
.page-about .timeline .tl-node p {
  max-width: 34ch;
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--slate);
  opacity: 1;
}

/* 团队与伙伴 */
.page-about .crew {
  display: grid;
  gap: 12px;
  margin: clamp(18px, 2.6vw, 26px) 0;
  padding: clamp(18px, 2.4vw, 26px);
}
.page-about .crew__line {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ivory);
}
.page-about .crew__line .num {
  font-family: var(--font-mono);
  font-size: 22px;
  line-height: 1;
  color: var(--gold);
  letter-spacing: -0.02em;
}

/* 信息一览 */
.page-about .fact-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  margin: clamp(20px, 3vw, 28px) 0 16px;
  border-top: 1px solid var(--about-hair);
}
.page-about .fact-item {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 0;
  border-bottom: 1px solid var(--about-hair);
}
.page-about .fact-item dt {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--slate);
}
.page-about .fact-item dd {
  margin: 0;
  font-size: 14px;
  text-align: right;
  color: var(--ivory);
}
.page-about .fact-item dd.num {
  font-family: var(--font-mono);
}
@media (min-width: 720px) {
  .page-about .fact-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(20px, 4vw, 52px);
  }
}

/* 收尾 */
.page-about .about-tail {
  padding-top: clamp(36px, 5vw, 60px);
  border-top: 1px solid var(--about-hair);
}
.page-about .about-tail__title {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--gold);
}
.page-about .about-tail__links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px 30px;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tier,
  .page-about .tl-node {
    transition: none;
  }
  .page-about .tier:hover {
    transform: none;
  }
}