.page-about {
  --ab-sec-pad: clamp(40px, 7vw, 88px);
  --ab-line: 1px solid var(--ink-600);
  background: var(--ink-950);
  color: var(--paper);
  font-family: var(--font-body);
  overflow-x: hidden;
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-top: 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--mist);
}
.page-about .crumbs a {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--t-fast), border-color var(--t-fast);
}
.page-about .crumbs a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding: clamp(26px, 5vw, 52px) 0 clamp(44px, 7vw, 84px);
  background: linear-gradient(180deg, var(--ink-900) 0%, var(--ink-950) 72%);
  border-bottom: var(--ab-line);
}
.page-about .ab-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(90deg, rgba(38, 52, 79, .5) 0 1px, transparent 1px 104px);
  opacity: .55;
  pointer-events: none;
}
.page-about .ab-hero-inner {
  position: relative;
  z-index: 1;
}
.page-about .ab-rail {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 22px 0 22px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--gold);
}
.page-about .ab-rail i {
  display: block;
  flex: 1 1 auto;
  max-width: 240px;
  height: 1px;
  background: linear-gradient(90deg, var(--gold), rgba(228, 180, 90, 0));
}
.page-about .eyebrow {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--gold);
}
.page-about .ab-hero h1 {
  margin: 0 0 22px;
  max-width: 17ch;
  font-family: var(--font-display);
  font-size: clamp(34px, 7.2vw, 74px);
  font-weight: 700;
  line-height: .98;
  letter-spacing: -.02em;
  color: var(--paper);
}
.page-about .ab-lede {
  margin: 0;
  max-width: 44em;
  font-size: 17px;
  line-height: 1.78;
  color: var(--paper-dim);
}
.page-about .ab-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 30px;
  padding-top: 22px;
  border-top: var(--ab-line);
}
.page-about .ab-jump a {
  padding: 6px 12px;
  border: 1px solid var(--ink-600);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--mist);
  text-decoration: none;
  transition: color var(--t-fast), border-color var(--t-fast), background var(--t-fast);
}
.page-about .ab-jump a:hover {
  color: var(--cyan);
  border-color: var(--cyan);
  background: var(--cyan-soft);
}

/* ---------- 通用区块 ---------- */
.page-about .ab-sec {
  padding: var(--ab-sec-pad) 0;
  border-bottom: var(--ab-line);
}
.page-about .section-head {
  max-width: 62ch;
  margin-bottom: 30px;
}
.page-about .ab-sec h2,
.page-about .ab-band h2,
.page-about .ab-next h2 {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: clamp(22px, 3.4vw, 34px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -.01em;
}
.page-about .ab-sub,
.page-about .ab-band-lede {
  margin: 0;
  max-width: 56ch;
  font-size: 16px;
  line-height: 1.72;
  color: var(--paper-dim);
}
.page-about .prose p {
  margin: 0 0 16px;
  font-size: 17px;
  line-height: 1.78;
  color: var(--paper-dim);
}
.page-about .prose p:last-child {
  margin-bottom: 0;
}

/* ---------- 第一节：起点 ---------- */
.page-about .ab-why-aside {
  margin-bottom: 26px;
}
.page-about .ab-bignum {
  margin: 0 0 14px;
  font-size: clamp(52px, 11vw, 96px);
  line-height: .88;
  letter-spacing: -.04em;
  color: var(--gold);
}
.page-about .ab-aside-quote {
  margin: 0;
  padding-left: 14px;
  max-width: 24ch;
  border-left: 3px solid var(--jbo-red);
  font-size: 15px;
  line-height: 1.7;
  color: var(--paper-dim);
}
.page-about .ab-why-body .prose p:first-child {
  padding-left: 16px;
  border-left: 3px solid var(--jbo-red);
}

/* ---------- 图片容器 ---------- */
.page-about .ab-fig {
  margin: 30px 0 0;
  padding: 10px;
  border: var(--ab-line);
  border-radius: var(--radius);
  background: var(--ink-900);
}
.page-about .ab-fig img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: 2px;
}
.page-about .ab-fig figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .05em;
  color: var(--mist);
}
.page-about .ab-fig--flow {
  margin: 0 0 32px;
}

/* ---------- 第二节：四个角色 ---------- */
.page-about .ab-team-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}
.page-about .ab-role {
  position: relative;
  height: 100%;
  padding: 22px 20px 26px;
  border: var(--ab-line);
  border-radius: var(--radius);
  background: var(--ink-900);
  box-shadow: 6px 6px 0 var(--ink-800);
}
.page-about .ab-role::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 38px;
  height: 2px;
  background: var(--gold);
}
.page-about .ab-role-tag {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--cyan);
}
.page-about .ab-role h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}
.page-about .ab-role p:not(.ab-role-tag) {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--paper-dim);
}
.page-about .ab-role-num {
  position: absolute;
  right: 14px;
  bottom: 8px;
  font-size: 40px;
  line-height: 1;
  letter-spacing: -.05em;
  color: var(--gold);
  opacity: .42;
}

/* ---------- 第三节：时间轴 ---------- */
.page-about .ab-tl {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .ab-tl::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold), var(--ink-600) 62%, transparent);
}
.page-about .ab-tl-item {
  position: relative;
  padding-left: 36px;
  margin-bottom: 14px;
}
.page-about .ab-tl-item:last-child {
  margin-bottom: 0;
}
.page-about .ab-tl-item::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 18px;
  z-index: 1;
  width: 13px;
  height: 13px;
  box-sizing: border-box;
  border: 2px solid var(--gold);
  border-radius: 50%;
  background: var(--ink-950);
}
.page-about .ab-tl-item--now::before {
  border-color: var(--jbo-red);
  background: var(--jbo-red);
}
.page-about .ab-tl-card {
  border: var(--ab-line);
  border-radius: var(--radius);
  background: var(--ink-900);
  transition: border-color var(--t-fast), background var(--t-fast);
}
.page-about .ab-tl-card[open] {
  border-color: var(--cyan);
  background: var(--ink-800);
}
.page-about .ab-tl-sum {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 15px 44px 15px 16px;
  cursor: pointer;
  list-style: none;
}
.page-about .ab-tl-sum::-webkit-details-marker {
  display: none;
}
.page-about .ab-tl-sum::marker {
  content: "";
}
.page-about .ab-tl-year {
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--gold);
}
.page-about .ab-tl-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--paper);
}
.page-about .ab-tl-toggle {
  position: absolute;
  right: 16px;
  top: 50%;
  width: 14px;
  height: 14px;
  transform: translateY(-50%);
}
.page-about .ab-tl-toggle::before,
.page-about .ab-tl-toggle::after {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 14px;
  height: 2px;
  background: var(--cyan);
  transition: transform var(--t-fast);
}
.page-about .ab-tl-toggle::after {
  transform: rotate(90deg);
}
.page-about .ab-tl-card[open] .ab-tl-toggle::after {
  transform: rotate(0deg);
}
.page-about .ab-tl-body {
  padding: 0 16px 18px;
}
.page-about .ab-tl-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.74;
  color: var(--paper-dim);
}
.page-about .ab-tl-body ul {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: grid;
  gap: 7px;
}
.page-about .ab-tl-body li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--mist);
}
.page-about .ab-tl-body li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 7px;
  height: 1px;
  background: var(--cyan);
}

/* ---------- 第四节：全宽数据带 ---------- */
.page-about .ab-band {
  position: relative;
  overflow: hidden;
  padding: clamp(46px, 8vw, 92px) 0;
  border-top: var(--ab-line);
  border-bottom: var(--ab-line);
  background: linear-gradient(135deg, var(--ink-800) 0%, var(--ink-900) 58%, var(--ink-950) 100%);
}
.page-about .ab-band-bg {
  position: absolute;
  right: -12%;
  top: 50%;
  width: min(680px, 86%);
  height: auto;
  transform: translateY(-50%);
  opacity: .14;
  mix-blend-mode: screen;
  pointer-events: none;
}
.page-about .ab-band-inner {
  position: relative;
  z-index: 1;
}
.page-about .ab-stats {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 14px;
}
.page-about .ab-stats li {
  padding-top: 14px;
  border-top: 2px solid var(--gold);
}
.page-about .ab-stat-num {
  display: block;
  font-size: clamp(32px, 5.4vw, 54px);
  line-height: 1;
  letter-spacing: -.04em;
  color: var(--paper);
}
.page-about .ab-stat-num em {
  margin-left: 4px;
  font-style: normal;
  font-size: .42em;
  color: var(--gold);
}
.page-about .ab-stat-label {
  display: block;
  margin-top: 10px;
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--mist);
}
.page-about .ab-stats-note {
  margin: 26px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 第五节：更新节奏 ---------- */
.page-about .ab-quality {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.page-about .ab-qcard {
  display: flex;
  flex-direction: column;
  gap: 12px;
  height: 100%;
  padding: 20px;
  border: var(--ab-line);
  border-radius: var(--radius);
  background: var(--ink-900);
}
.page-about .ab-qcard .chip {
  align-self: flex-start;
}
.page-about .ab-qcard h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}
.page-about .ab-qcard > p {
  flex: 1 1 auto;
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--paper-dim);
}
.page-about .ab-qcard-foot {
  margin: 0;
  padding-top: 10px;
  border-top: 1px dashed var(--ink-600);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--gold);
}
.page-about .ab-quality-note {
  margin: 26px 0 0;
  padding-left: 16px;
  border-left: 3px solid var(--jbo-red);
  font-size: 15px;
  line-height: 1.7;
  color: var(--paper-dim);
}

/* ---------- 第六节：来信条形图 ---------- */
.page-about .ab-bars {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 20px;
}
.page-about .ab-bar-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas:
    "label val"
    "track track";
  gap: 8px 12px;
  align-items: center;
}
.page-about .ab-bar-label {
  grid-area: label;
  font-size: 15px;
  color: var(--paper);
}
.page-about .ab-bar-val {
  grid-area: val;
  font-size: 16px;
  color: var(--gold);
}
.page-about .ab-bar-track {
  position: relative;
  grid-area: track;
  height: 14px;
  border-radius: 2px;
  background-color: var(--ink-800);
  background-image: repeating-linear-gradient(90deg, var(--ink-600) 0 1px, transparent 1px 10%);
}
.page-about .ab-bar-fill {
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--cyan), rgba(51, 208, 222, .5));
  transition: filter var(--t-fast);
}
.page-about .ab-bar-fill--42 {
  width: 42%;
  background: linear-gradient(90deg, var(--jbo-red), rgba(225, 58, 70, .55));
}
.page-about .ab-bar-fill--21 { width: 21%; }
.page-about .ab-bar-fill--18 { width: 18%; }
.page-about .ab-bar-fill--19 { width: 19%; }
.page-about .ab-bar-row:hover .ab-bar-fill {
  filter: brightness(1.18);
}
.page-about .ab-bar-tip {
  position: absolute;
  right: 0;
  bottom: calc(100% + 7px);
  padding: 4px 8px;
  border-radius: 2px;
  background: var(--gold);
  color: var(--ink-950);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .04em;
  white-space: nowrap;
  opacity: 0;
  transform: translateY(4px);
  pointer-events: none;
  transition: opacity var(--t-fast), transform var(--t-fast);
}
.page-about .ab-bar-row:hover .ab-bar-tip,
.page-about .ab-bar-row:focus-within .ab-bar-tip {
  opacity: 1;
  transform: translateY(0);
}
.page-about .ab-bars-note {
  margin: 26px 0 0;
  max-width: 58ch;
  font-size: 14px;
  line-height: 1.72;
  color: var(--mist);
}

/* ---------- 结尾导航 ---------- */
.page-about .ab-next {
  padding: var(--ab-sec-pad) 0;
}
.page-about .ab-next-list {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}
.page-about .ab-next-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 16px 18px;
  border: var(--ab-line);
  border-radius: var(--radius);
  background: var(--ink-900);
  text-decoration: none;
  transition: border-color var(--t-fast), background var(--t-fast), transform var(--t-fast);
}
.page-about .ab-next-list a:hover {
  border-color: var(--cyan);
  background: var(--ink-800);
  transform: translateX(4px);
}
.page-about .ab-next-text {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.page-about .ab-next-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--paper);
}
.page-about .ab-next-desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
}
.page-about .ab-next-arrow {
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--cyan);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .ab-team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .ab-next-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 760px) {
  .page-about .ab-bar-row {
    grid-template-columns: minmax(150px, 230px) minmax(0, 1fr) 64px;
    grid-template-areas: "label track val";
    gap: 16px;
  }
  .page-about .ab-bar-val {
    text-align: right;
  }
  .page-about .ab-stats {
    gap: 24px 18px;
  }
}

@media (min-width: 900px) {
  .page-about .ab-tl::before {
    left: 50%;
    transform: translateX(-50%);
  }
  .page-about .ab-tl-item {
    width: 50%;
    padding-left: 0;
    padding-right: 42px;
    margin-bottom: 18px;
  }
  .page-about .ab-tl-item:nth-child(even) {
    margin-left: 50%;
    padding-right: 0;
    padding-left: 42px;
  }
  .page-about .ab-tl-item::before {
    left: auto;
    right: -7px;
    top: 22px;
  }
  .page-about .ab-tl-item:nth-child(even)::before {
    right: auto;
    left: -7px;
  }
}

@media (min-width: 1024px) {
  .page-about .ab-team-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    align-items: start;
  }
  .page-about .ab-team-grid > li:nth-child(2) { margin-top: 22px; }
  .page-about .ab-team-grid > li:nth-child(3) { margin-top: 44px; }
  .page-about .ab-team-grid > li:nth-child(4) { margin-top: 66px; }
  .page-about .ab-quality {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .ab-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .ab-why-aside {
    margin-bottom: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-next-list a:hover {
    transform: none;
  }
  .page-about .ab-bar-tip {
    transform: none;
  }
}