.page-about {
  background: var(--paper);
  color: var(--brown);
}

/* ============ 首屏 ============ */
.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(18px, 3vw, 34px) 0 clamp(40px, 6vw, 76px);
  border-bottom: 1px solid var(--rule);
  background:
    radial-gradient(circle at 88% 4%, rgba(230, 58, 46, 0.13), transparent 58%),
    linear-gradient(180deg, rgba(201, 183, 156, 0.18), transparent 46%);
}
.page-about .ab-hero__inner {
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  align-items: end;
}
.page-about .ab-hero h1 {
  margin: 0.34em 0 0;
  font-size: clamp(30px, 5.4vw, 60px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--ink);
}
.page-about .ab-hero__lede {
  margin: clamp(16px, 2.2vw, 24px) 0 0;
  max-width: 44ch;
  font-size: clamp(15px, 1.4vw, 17px);
  line-height: 1.95;
  color: var(--brown);
}
.page-about .ab-hero__acts {
  margin-top: clamp(20px, 3vw, 30px);
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .ab-hero__panel {
  position: relative;
  padding: clamp(20px, 3vw, 30px);
  border: 1px solid var(--rule);
  background-color: rgba(255, 255, 255, 0.42);
  background-image: var(--grain);
  background-size: 6px 6px;
}
.page-about .ab-hero__panel::before {
  content: "";
  position: absolute;
  inset: 6px;
  border: 1px dashed rgba(230, 58, 46, 0.34);
  pointer-events: none;
}
.page-about .ab-hero__big {
  position: relative;
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(66px, 11vw, 112px);
  line-height: 0.88;
  letter-spacing: -0.04em;
  color: var(--red);
}
.page-about .ab-hero__panel-k {
  position: relative;
  display: block;
  margin-top: 6px;
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
}
.page-about .ab-hero__quick {
  position: relative;
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 0;
}
.page-about .ab-hero__quick li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 0;
  border-top: 1px dashed rgba(201, 183, 156, 0.9);
  font-size: 13.5px;
  line-height: 1.7;
  color: #4a3d35;
}
.page-about .ab-hero__quick li::before {
  content: "";
  flex: none;
  width: 7px;
  height: 7px;
  background: var(--red);
  transform: translateY(-1px);
}

.page-about .ab-hero__media {
  margin-top: clamp(26px, 4.5vw, 52px);
}
.page-about .ab-hero__media img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

/* ============ 区块通用 ============ */
.page-about .ab-sec {
  padding: clamp(48px, 7vw, 96px) 0;
}
.page-about .ab-head {
  max-width: 62ch;
  margin-bottom: clamp(26px, 4vw, 46px);
}
.page-about .ab-head h2 {
  margin: 0.3em 0 0;
  font-size: clamp(24px, 3.4vw, 40px);
  line-height: 1.18;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--ink);
}
.page-about .ab-head p {
  margin: clamp(12px, 1.6vw, 18px) 0 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.95;
  color: #4a3d35;
}
.page-about .section--ink .ab-head h2 {
  color: var(--paper);
}
.page-about .section--ink .ab-head p {
  color: rgba(245, 239, 227, 0.78);
}
.page-about .section--ink .eyebrow {
  color: var(--lime);
}

/* ============ 三张标签卡 ============ */
.page-about .ab-cards {
  display: grid;
  gap: clamp(16px, 2.4vw, 26px);
}
.page-about .ab-tag {
  position: relative;
  padding: clamp(20px, 2.6vw, 28px);
  border: 1px solid var(--rule);
  background-color: rgba(255, 255, 255, 0.4);
  background-image: var(--grain);
  background-size: 6px 6px;
  transition: border-color 0.3s var(--ease), transform 0.3s var(--ease);
}
.page-about .ab-tag::after {
  content: "";
  position: absolute;
  right: 14px;
  bottom: 14px;
  width: 10px;
  height: 10px;
  background: var(--rule);
  transition: background-color 0.3s var(--ease);
}
.page-about .ab-tag:hover {
  border-color: var(--red);
  transform: translateY(-3px);
}
.page-about .ab-tag:hover::after {
  background: var(--lime);
}
.page-about .ab-tag__no {
  display: block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--slate);
}
.page-about .ab-tag h3 {
  margin: 12px 0 0;
  font-size: clamp(17px, 1.8vw, 20px);
  line-height: 1.4;
  color: var(--ink);
}
.page-about .ab-tag p {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.9;
  color: #4a3d35;
}

/* ============ 版本时间轴 ============ */
.page-about .ab-versions {
  background:
    linear-gradient(180deg, rgba(201, 183, 156, 0.22), transparent 30%),
    var(--paper);
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
}
.page-about .ab-versions__inner {
  position: relative;
}
.page-about .ab-vnote {
  display: none;
}
.page-about .ab-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(22px, 3.4vw, 36px);
}
.page-about .ab-node {
  position: relative;
  padding-left: 54px;
}
.page-about .ab-node::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 12px;
  bottom: calc(-1 * clamp(22px, 3.4vw, 36px));
  width: 2px;
  background: var(--rule);
}
.page-about .ab-node:last-child::before {
  display: none;
}
.page-about .ab-node__dot {
  position: absolute;
  left: 6px;
  top: 8px;
  width: 20px;
  height: 20px;
  background: var(--red);
  border: 4px solid var(--paper);
  box-shadow: 0 0 0 1px var(--red);
  z-index: 1;
  transition: background-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}
.page-about .ab-node:last-child .ab-node__dot {
  background: var(--lime);
  box-shadow: 0 0 0 1px var(--rule);
}
.page-about .ab-node__ver {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(30px, 5vw, 46px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
}
.page-about .ab-node__tag {
  display: inline-block;
  margin-left: 10px;
  padding: 3px 8px;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--red);
  border: 1px solid var(--red);
  vertical-align: middle;
}
.page-about .ab-node h3 {
  margin: 12px 0 0;
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.4;
  color: var(--ink);
}
.page-about .ab-node__text {
  margin: 10px 0 0;
  max-width: 52ch;
  font-size: 14.5px;
  line-height: 1.95;
  color: #4a3d35;
}
.page-about .ab-node__more {
  display: grid;
  grid-template-rows: 1fr;
  transition: grid-template-rows 0.4s var(--ease);
}
.page-about .ab-node__more ul {
  overflow: hidden;
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .ab-node__more li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding-top: 8px;
  font-size: 13.5px;
  line-height: 1.75;
  color: #5c4d43;
}
.page-about .ab-node__more li::before {
  content: "";
  flex: none;
  width: 6px;
  height: 6px;
  margin-top: 8px;
  background: var(--coral);
}

/* ============ 更新节奏（深色） ============ */
.page-about .ab-rhythm__grid {
  display: grid;
  gap: clamp(26px, 4vw, 46px);
}
.page-about .ab-team {
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .ab-team li {
  display: grid;
  grid-template-columns: 60px minmax(0, 1fr);
  gap: 4px 18px;
  padding: 18px 0;
  border-top: 1px solid rgba(245, 239, 227, 0.16);
}
.page-about .ab-team li:last-child {
  border-bottom: 1px solid rgba(245, 239, 227, 0.16);
}
.page-about .ab-team__num {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: clamp(28px, 3.4vw, 42px);
  line-height: 1;
  color: var(--lime);
}
.page-about .ab-team__k {
  font-size: 15px;
  font-weight: 700;
  color: var(--paper);
}
.page-about .ab-team__v {
  font-size: 13.5px;
  line-height: 1.85;
  color: rgba(245, 239, 227, 0.72);
}

.page-about .ab-clock {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
  align-content: start;
}
.page-about .ab-clock li {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  padding: 14px 16px;
  border: 1px solid rgba(245, 239, 227, 0.18);
  background: var(--glass);
}
.page-about .ab-clock b {
  flex: none;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--lime);
}
.page-about .ab-clock span {
  flex: 1 1 200px;
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(245, 239, 227, 0.76);
}

.page-about .ab-rhythm__figure {
  margin: clamp(30px, 4.5vw, 56px) auto 0;
  max-width: 1000px;
}
.page-about .ab-rhythm__figure img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

/* ============ 合作生态 ============ */
.page-about .ab-coop {
  display: grid;
  gap: clamp(28px, 4vw, 52px);
  align-items: start;
}
.page-about .ab-coop__figure img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}
.page-about .ab-partners {
  list-style: none;
  margin: 0 0 clamp(24px, 3vw, 32px);
  padding: 0;
  display: grid;
  gap: 0;
}
.page-about .ab-partners li {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 4px 16px;
  padding: 16px 0;
  border-top: 1px solid var(--rule);
}
.page-about .ab-partners li:last-child {
  border-bottom: 1px solid var(--rule);
}
.page-about .ab-partners__num {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3vw, 34px);
  line-height: 1;
  color: var(--red);
}
.page-about .ab-partners__k {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}
.page-about .ab-partners p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: #4a3d35;
}

/* ============ 服务地区 ============ */
.page-about .ab-geo-sec {
  background:
    linear-gradient(180deg, rgba(230, 58, 46, 0.07), transparent 40%),
    var(--paper);
  border-top: 1px solid var(--rule);
}
.page-about .ab-geo {
  display: grid;
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
  margin-bottom: clamp(28px, 4vw, 48px);
}
.page-about .ab-geo__stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(18px, 2.6vw, 28px);
  background: var(--paper);
}
.page-about .ab-geo__num {
  font-family: var(--font-mono);
  font-size: clamp(36px, 6vw, 62px);
  line-height: 0.95;
  letter-spacing: -0.04em;
  color: var(--ink);
}
.page-about .ab-geo__unit {
  margin-left: 4px;
  font-size: 0.36em;
  letter-spacing: 0;
  color: var(--slate);
}
.page-about .ab-geo__k {
  font-size: 13.5px;
  line-height: 1.7;
  color: #4a3d35;
}

.page-about .ab-scene {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(18px, 2.6vw, 28px);
}
.page-about .ab-scene li {
  padding-left: 18px;
  border-left: 3px solid var(--red);
}
.page-about .ab-scene li:nth-child(2) {
  border-left-color: var(--coral);
}
.page-about .ab-scene li:nth-child(3) {
  border-left-color: var(--rule);
}
.page-about .ab-scene h3 {
  margin: 0;
  font-size: clamp(15px, 1.7vw, 18px);
  line-height: 1.5;
  color: var(--ink);
}
.page-about .ab-scene p {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.9;
  color: #4a3d35;
}

/* ============ 承诺 ============ */
.page-about .ab-promise__grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 24px);
}
.page-about .ab-promise__item {
  padding: clamp(20px, 2.6vw, 28px);
  border: 1px solid rgba(245, 239, 227, 0.2);
  background: var(--glass);
}
.page-about .ab-promise__item h3 {
  margin: 0;
  font-size: clamp(16px, 1.8vw, 19px);
  color: var(--paper);
}
.page-about .ab-promise__item p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.9;
  color: rgba(245, 239, 227, 0.76);
}
.page-about .ab-promise__item .btn {
  margin-top: 16px;
}
.page-about .ab-promise__mail {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 12px;
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px dashed rgba(245, 239, 227, 0.22);
}
.page-about .ab-promise__mailv {
  font-family: var(--font-mono);
  font-size: 13px;
  word-break: break-all;
  color: var(--lime);
}

/* ============ 响应式 ============ */
@media (min-width: 640px) {
  .page-about .ab-cards {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .ab-geo {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .ab-scene {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .ab-promise__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__inner {
    grid-template-columns: minmax(0, 1.6fr) minmax(300px, 1fr);
  }
  .page-about .ab-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .ab-rhythm__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }
  .page-about .ab-coop {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
    align-items: center;
  }
  .page-about .ab-scene {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .ab-promise__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr) minmax(0, 1fr);
  }
}

@media (min-width: 1100px) {
  .page-about .ab-vnote {
    display: block;
    position: absolute;
    right: -6px;
    top: 4px;
    margin: 0;
    writing-mode: vertical-rl;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.3em;
    color: var(--slate);
    pointer-events: none;
  }
  .page-about .ab-node {
    padding-left: 74px;
  }
  .page-about .ab-node__more {
    grid-template-rows: 0fr;
  }
  .page-about .ab-node:hover .ab-node__more,
  .page-about .ab-node:focus-within .ab-node__more {
    grid-template-rows: 1fr;
  }
  .page-about .ab-node:hover .ab-node__dot {
    background: var(--lime);
    box-shadow: 0 0 0 1px var(--rule);
  }
  .page-about .ab-node:hover .ab-node__ver {
    color: var(--red);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-tag,
  .page-about .ab-node__dot,
  .page-about .ab-node__more,
  .page-about .ab-tag::after {
    transition: none;
  }
  .page-about .ab-tag:hover {
    transform: none;
  }
}