.page-about {
  --about-rail-w: 172px;
  --about-tip-bg: var(--paper);
  padding-bottom: clamp(56px, 8vw, 120px);
}

/* 面包屑 */
.page-about .about-crumb {
  padding-top: clamp(18px, 3vw, 32px);
}

/* 首屏 */
.page-about .about-masthead {
  position: relative;
  margin-top: clamp(16px, 2.4vw, 26px);
  padding: clamp(34px, 5.6vw, 76px) 0 clamp(30px, 4vw, 52px);
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  background:
    repeating-linear-gradient(90deg, transparent 0 15px, rgba(241, 235, 224, .05) 15px 16px),
    linear-gradient(180deg, var(--deep-veil), rgba(10, 26, 34, 0) 72%);
}

.page-about .about-masthead__eyebrow {
  margin: 0;
  color: var(--amber);
  letter-spacing: .2em;
  font-size: 12px;
}

.page-about .about-masthead__title {
  margin: 16px 0 0;
  max-width: 20ch;
  font-size: clamp(30px, 5.4vw, 62px);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -.02em;
  color: var(--paper);
  transform: scaleY(1.03);
  transform-origin: left top;
}

.page-about .about-masthead__lead {
  margin: 22px 0 0;
  max-width: 33rem;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.75;
  color: var(--paper-72);
}

/* 首屏数据速览 */
.page-about .about-quick {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(146px, 1fr));
  gap: 1px;
  margin: clamp(30px, 4vw, 48px) 0 0;
  background: var(--rule);
  border: 1px solid var(--rule-strong);
}

.page-about .about-quick__cell {
  margin: 0;
  padding: 16px 16px 18px;
  background: var(--night);
}

.page-about .about-quick__label {
  font-size: 12.5px;
  letter-spacing: .08em;
  color: var(--paper-38);
}

.page-about .about-quick__value {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.4vw, 52px);
  font-weight: 900;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--amber);
}

.page-about .about-quick__unit {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--paper-56);
}

/* 章节骨架 */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 56px);
  padding-top: clamp(38px, 5.6vw, 72px);
}

@media (min-width: 960px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: clamp(40px, 5vw, 88px);
  }
}

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

@media (min-width: 960px) {
  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-lower-h) + 28px);
    align-self: start;
  }
}

.page-about .about-rail__title {
  margin: 0 0 16px;
  font-size: 12px;
  letter-spacing: .22em;
  color: var(--paper-38);
}

.page-about .about-rail__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 13px;
}

.page-about .about-rail__link {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding-left: 11px;
  border-left: 2px solid transparent;
  font-size: 13px;
  line-height: 1.5;
  color: var(--paper-38);
  text-decoration: none;
  transition: color .22s var(--ease), border-color .22s var(--ease);
}

.page-about .about-rail__link .num {
  font-family: var(--font-mono);
  font-size: 12px;
  color: inherit;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--lime);
  border-left-color: var(--lime);
}

/* 章节 */
.page-about .about-chapter {
  position: relative;
  border-top: 1px solid var(--rule-strong);
  padding-top: clamp(20px, 2.8vw, 32px);
  padding-bottom: clamp(30px, 4.2vw, 60px);
}

.page-about .about-chapter + .about-chapter {
  margin-top: clamp(10px, 2vw, 26px);
}

.page-about .about-chapter__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 20px;
}

.page-about .about-chapter__num {
  font-family: var(--font-mono);
  font-size: clamp(42px, 6vw, 84px);
  font-weight: 900;
  line-height: .84;
  letter-spacing: -.05em;
  color: var(--amber);
}

.page-about .about-chapter__title {
  flex: 1 1 230px;
  margin: 0;
  font-size: clamp(21px, 2.6vw, 30px);
  font-weight: 900;
  line-height: 1.26;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-chapter__body {
  margin-top: clamp(18px, 2.4vw, 28px);
}

.page-about .about-chapter__body p {
  max-width: 34rem;
  line-height: 1.75;
  color: var(--paper-72);
}

.page-about .about-chapter__body__tail {
  margin-top: clamp(20px, 2.6vw, 30px);
}

.page-about .about-lede {
  margin: 0 0 clamp(20px, 2.6vw, 30px);
  max-width: 36rem;
  font-size: clamp(15.5px, 1.5vw, 17px);
  line-height: 1.75;
  color: var(--paper-72);
}

.page-about .about-subtitle {
  margin: 0 0 4px;
  font-size: 16px;
  font-weight: 900;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-chapter__note {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  padding-left: 13px;
  border-left: 2px solid var(--clay);
  max-width: 46rem;
  font-size: 13px;
  line-height: 1.75;
  color: var(--paper-38);
}

/* 栅格 */
.page-about .grid--split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 38px);
}

.page-about .grid--thirds {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

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

@media (min-width: 880px) {
  .page-about .grid--split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .grid--split.about-timing {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    align-items: start;
  }
}

/* 列表 */
.page-about .about-list {
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.page-about .about-list li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--paper-72);
}

.page-about .about-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .74em;
  width: 9px;
  height: 2px;
  background: var(--ice);
}

.page-about .about-list li strong {
  color: var(--paper);
  font-weight: 700;
}

.page-about .panel--paper .about-list li {
  color: inherit;
}

.page-about .panel--paper .about-list li::before {
  background: var(--clay);
}

/* 分类比例条 */
.page-about .cat-bar {
  display: grid;
  grid-template-columns: 12fr 18fr 10fr;
  gap: 3px;
  margin-top: 4px;
  padding: 3px;
  border: 1px solid var(--rule-strong);
  background: var(--night);
}

.page-about .cat-bar__seg {
  position: relative;
  min-height: 148px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: 5px;
  padding: 12px 12px 14px;
  outline: none;
  border-top: 3px solid transparent;
}

.page-about .cat-bar__seg--inter {
  border-top-color: var(--lime);
  background: linear-gradient(180deg, rgba(79, 107, 75, .26), rgba(79, 107, 75, .62));
}

.page-about .cat-bar__seg--region {
  border-top-color: var(--ice);
  background: linear-gradient(180deg, rgba(16, 43, 39, .58), rgba(16, 43, 39, .96));
}

.page-about .cat-bar__seg--invite {
  border-top-color: var(--clay);
  background: linear-gradient(180deg, rgba(181, 100, 60, .28), rgba(181, 100, 60, .6));
}

.page-about .cat-bar__seg:focus-visible {
  outline: 2px solid var(--ice);
  outline-offset: 2px;
}

.page-about .cat-bar__num {
  font-family: var(--font-mono);
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 900;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--paper);
}

.page-about .cat-bar__name {
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--paper-72);
}

.page-about .cat-bar__tip {
  position: absolute;
  left: 0;
  bottom: calc(100% + 10px);
  width: max(210px, 100%);
  padding: 10px 12px;
  background: var(--about-tip-bg);
  border-left: 3px solid var(--lime);
  color: var(--night);
  font-size: 12.5px;
  line-height: 1.65;
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity .22s var(--ease), transform .22s var(--ease), visibility .22s;
  pointer-events: none;
  z-index: 6;
}

.page-about .cat-bar__seg--invite .cat-bar__tip {
  left: auto;
  right: 0;
}

.page-about .cat-bar__seg:hover .cat-bar__tip,
.page-about .cat-bar__seg:focus .cat-bar__tip,
.page-about .cat-bar__seg:focus-visible .cat-bar__tip {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* 团队数据 */
.page-about .about-figure {
  margin: 0 0 clamp(22px, 3vw, 34px);
}

.page-about .media-frame {
  margin: 0;
}

.page-about .media-frame img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-about .team-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(126px, 1fr));
  gap: 1px;
  margin: 0 0 clamp(22px, 3vw, 32px);
  background: var(--rule);
  border: 1px solid var(--rule-strong);
}

.page-about .team-stat {
  padding: 16px 14px 18px;
  background: var(--night);
}

.page-about .team-stat__v {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(28px, 3.6vw, 46px);
  font-weight: 900;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--lime);
}

.page-about .team-stat__l {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--paper-56);
}

/* 表格 */
.page-about .about-table-wrap {
  margin-top: clamp(16px, 2vw, 24px);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-table {
  width: 100%;
  min-width: 520px;
  border-collapse: collapse;
  font-size: 14.5px;
}

.page-about .about-table caption {
  padding-bottom: 10px;
  text-align: left;
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--paper-38);
}

.page-about .about-table th,
.page-about .about-table td {
  padding: 12px 14px;
  border: 1px solid var(--rule);
  text-align: left;
  vertical-align: top;
  line-height: 1.65;
}

.page-about .about-table thead th {
  background: var(--deep);
  color: var(--paper);
  font-weight: 700;
  letter-spacing: .02em;
}

.page-about .about-table tbody th {
  color: var(--paper);
  font-weight: 700;
  white-space: nowrap;
}

.page-about .about-table td {
  color: var(--paper-72);
}

.page-about .about-table td.num {
  font-family: var(--font-mono);
  color: var(--ice);
  white-space: nowrap;
}

/* 复核流程 */
.page-about .flow {
  margin: clamp(20px, 2.6vw, 30px) 0 clamp(30px, 4vw, 52px);
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

@media (min-width: 760px) {
  .page-about .flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 26px 24px;
    padding-bottom: 20px;
  }

  .page-about .flow__step:nth-child(even) {
    transform: translateY(20px);
  }

  .page-about .flow__step:nth-child(3) {
    transform: translateY(6px) rotate(.4deg);
  }

  .page-about .flow__step:nth-child(4) {
    transform: translateY(26px) rotate(-.5deg);
  }
}

.page-about .flow__step {
  position: relative;
  padding: 18px 18px 20px;
  background: var(--deep);
  border: 1px solid var(--rule-strong);
  box-shadow: -6px 6px 0 rgba(10, 26, 34, .68);
}

.page-about .flow__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 900;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--amber);
}

.page-about .flow__title {
  margin: 12px 0 0;
  font-size: 17px;
  font-weight: 900;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .flow__text {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--paper-72);
}

.page-about .flow__step .note {
  margin-top: 14px;
}

.page-about .flow__step .note-body__inner ul {
  margin: 0;
  padding-left: 18px;
  line-height: 1.7;
}

/* 版本折线 */
.page-about .version-track {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0 0 clamp(96px, 12vw, 132px);
  list-style: none;
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 10px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

@media (max-width: 820px) {
  .page-about .version-track {
    grid-template-columns: repeat(6, 104px);
  }
}

.page-about .version-node {
  position: relative;
  padding: calc(22px + var(--drop, 0px)) 0 0 12px;
  border-left: 1px solid var(--rule-strong);
  outline: none;
}

.page-about .version-node:nth-child(1) { --drop: 0px; }
.page-about .version-node:nth-child(2) { --drop: 14px; }
.page-about .version-node:nth-child(3) { --drop: 30px; }
.page-about .version-node:nth-child(4) { --drop: 16px; }
.page-about .version-node:nth-child(5) { --drop: 36px; }
.page-about .version-node:nth-child(6) { --drop: 8px; }

.page-about .version-node__dot {
  position: absolute;
  left: -4px;
  top: calc(16px + var(--drop, 0px));
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--lime);
}

.page-about .version-node:last-child .version-node__dot {
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(233, 169, 60, .18);
}

.page-about .version-node__tag {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(16px, 2vw, 22px);
  font-weight: 900;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .version-node__tip {
  position: absolute;
  top: 100%;
  left: 0;
  margin-top: 12px;
  width: 200px;
  padding: 10px 12px;
  background: var(--about-tip-bg);
  border-left: 3px solid var(--amber);
  color: var(--night);
  font-size: 12.5px;
  line-height: 1.65;
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity .22s var(--ease), transform .22s var(--ease), visibility .22s;
  pointer-events: none;
  z-index: 6;
}

.page-about .version-node:last-child .version-node__tip {
  left: auto;
  right: 0;
}

.page-about .version-node:hover .version-node__tip,
.page-about .version-node:focus .version-node__tip,
.page-about .version-node:focus-visible .version-node__tip {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.page-about .version-node:focus-visible {
  outline: 2px solid var(--ice);
  outline-offset: 4px;
}

/* 沟通路径卡片 */
.page-about .path-card {
  padding: 18px 18px 20px;
  background: var(--deep);
  border: 1px solid var(--rule-strong);
  border-top: 3px solid var(--moss);
}

.page-about .path-card:nth-child(2) {
  border-top-color: var(--lime);
}

.page-about .path-card:nth-child(3) {
  border-top-color: var(--clay);
}

.page-about .path-card__title {
  margin: 0 0 10px;
  font-size: 16px;
  font-weight: 900;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .path-card p {
  margin: 0;
  max-width: none;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--paper-72);
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(20px, 2.6vw, 28px);
}

/* 继续查阅 */
.page-about .about-next {
  margin-top: clamp(40px, 6vw, 84px);
  padding-top: clamp(24px, 3vw, 38px);
  border-top: 1px solid var(--rule-strong);
}

.page-about .about-next__title {
  margin: 0;
  font-size: clamp(18px, 2.2vw, 24px);
  font-weight: 900;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-next__list {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
}

@media (min-width: 760px) {
  .page-about .about-next__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .page-about .about-next__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-next__item {
  padding: 16px 16px 18px;
  background: var(--night);
}

.page-about .about-next__link {
  display: inline-block;
  font-size: 15px;
  font-weight: 700;
  color: var(--ice);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.page-about .about-next__link:hover {
  color: var(--lime);
}

.page-about .about-next__desc {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--paper-56);
}

/* 窄屏兜底 */
@media (max-width: 720px) {
  .page-about .cat-bar {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .cat-bar__seg {
    min-height: 0;
  }

  .page-about .cat-bar__tip {
    position: static;
    width: auto;
    margin-top: 10px;
    padding: 8px 0 0;
    background: transparent;
    border-left: 2px solid var(--rule-strong);
    color: var(--paper-72);
    opacity: 1;
    visibility: visible;
    transform: none;
    padding-left: 10px;
  }

  .page-about .flow__step {
    box-shadow: -4px 4px 0 rgba(10, 26, 34, .68);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .cat-bar__tip,
  .page-about .version-node__tip,
  .page-about .about-rail__link {
    transition: none;
  }

  .page-about .flow__step {
    transform: none !important;
  }
}