.page-about {
  --about-gap: clamp(20px, 3.4vw, 40px);
  --about-panel: rgba(18, 38, 58, .72);
  padding-top: clamp(14px, 2.6vw, 32px);
  overflow-x: clip;
}

.page-about .wrap {
  width: 100%;
  min-width: 0;
}

.page-about .eyebrow {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--electric);
}

.page-about .muted {
  color: var(--text-2);
}

.page-about .grid {
  display: grid;
  gap: var(--about-gap);
  min-width: 0;
}

.page-about .section {
  padding: clamp(30px, 5.6vw, 68px) 0;
  min-width: 0;
}

.page-about p {
  overflow-wrap: anywhere;
}

/* ---------- 面包屑 ---------- */

.page-about .breadcrumbs {
  padding: 6px 0 0;
}

.page-about .breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0 clamp(18px, 4vw, 56px);
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-2);
}

.page-about .breadcrumbs__link {
  color: var(--text-2);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .16s ease, border-color .16s ease;
}

.page-about .breadcrumbs__link:hover,
.page-about .breadcrumbs__link:focus-visible {
  color: var(--electric);
  border-bottom-color: var(--electric);
}

.page-about .breadcrumbs__sep {
  color: var(--line);
}

.page-about .breadcrumbs__item [aria-current="page"] {
  color: var(--gold-lite);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding: clamp(22px, 4.4vw, 52px) 0 clamp(28px, 5vw, 60px);
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(44, 201, 183, .14), transparent 58%),
    radial-gradient(80% 70% at 4% 100%, rgba(212, 162, 76, .12), transparent 62%);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero__inner {
  display: grid;
  gap: clamp(18px, 3vw, 32px);
  padding-left: clamp(18px, 4vw, 56px);
  padding-right: clamp(18px, 4vw, 56px);
}

.page-about .about-hero__aside {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-hero__index {
  font-size: clamp(34px, 7vw, 62px);
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px var(--steel);
  letter-spacing: .02em;
}

.page-about .about-hero__title {
  margin: 0 0 clamp(16px, 2.4vw, 24px);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: clamp(29px, 5.2vw, 54px);
  line-height: 1.2;
  letter-spacing: -.01em;
  color: var(--text);
  max-width: 20ch;
}

.page-about .about-hero__lead {
  margin: 0 0 clamp(22px, 3.4vw, 34px);
  max-width: 62ch;
  font-size: clamp(15px, 1.5vw, 18px);
  line-height: 1.8;
  color: var(--text-2);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-hero__fact {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: clamp(14px, 2.4vw, 20px);
  background: var(--ink-2);
}

.page-about .about-hero__fact-num {
  font-size: clamp(22px, 3.4vw, 30px);
  line-height: 1;
  color: var(--gold);
  letter-spacing: -.01em;
}

.page-about .about-hero__fact-label {
  font-size: 13px;
  color: var(--text-2);
}

/* ---------- 品牌由来 ---------- */

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

.page-about .about-origin__note {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  padding-left: 14px;
  border-left: 2px solid var(--celadon);
}

.page-about .about-origin__title,
.page-about .about-columns-section__title,
.page-about .about-versions__title,
.page-about .about-service__title,
.page-about .about-team__title,
.page-about .about-timeline__title,
.page-about .about-promise__title {
  margin: 0 0 clamp(14px, 2.2vw, 22px);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: clamp(23px, 3.4vw, 38px);
  line-height: 1.28;
  color: var(--text);
}

.page-about .about-origin__text,
.page-about .about-versions__text,
.page-about .about-team__text {
  margin: 0 0 16px;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--text-2);
}

.page-about .about-origin__figure {
  margin: clamp(22px, 3.6vw, 36px) 0 0;
}

.page-about .media-frame {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--ink-2);
  overflow: hidden;
}

.page-about .media-frame__inner {
  display: block;
  background:
    linear-gradient(0deg, rgba(11, 27, 43, .35), rgba(11, 27, 43, .35)),
    repeating-linear-gradient(90deg, rgba(42, 64, 88, .35) 0 1px, transparent 1px 34px);
}

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

.page-about .media-frame__caption {
  padding: 12px clamp(14px, 2.4vw, 20px);
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-2);
  border-top: 1px solid var(--line);
}

/* ---------- 内容中心 ---------- */

.page-about .about-columns-section {
  background: linear-gradient(180deg, rgba(18, 38, 58, .82), rgba(11, 27, 43, 0) 88%);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .about-columns-section__head {
  display: grid;
  gap: clamp(14px, 2.4vw, 26px);
  margin-bottom: clamp(22px, 3.6vw, 38px);
}

.page-about .about-columns-section__lead {
  margin: 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.8;
  color: var(--text-2);
}

.page-about .about-columns__visual {
  margin: 0 0 clamp(20px, 3.4vw, 34px);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--ink-2);
}

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

.page-about .filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: clamp(18px, 3vw, 28px);
}

.page-about .filter-btn {
  appearance: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(30, 58, 95, .5);
  color: var(--text-2);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  padding: 8px 15px;
  cursor: pointer;
  transition: color .16s ease, border-color .16s ease, background-color .16s ease;
}

.page-about .filter-btn:hover,
.page-about .filter-btn:focus-visible {
  color: var(--text);
  border-color: var(--electric);
}

.page-about .filter-btn[aria-pressed="true"] {
  background: rgba(44, 201, 183, .16);
  border-color: var(--electric);
  color: var(--electric);
}

.page-about .about-columns {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.page-about .column-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(18px, 2.6vw, 26px);
  background: var(--ink-2);
  transition: background-color .18s ease;
}

.page-about .column-card:hover {
  background: var(--steel);
}

.page-about .column-card__idx {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--celadon);
}

.page-about .column-card__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: 19px;
  font-weight: 700;
  color: var(--text);
}

.page-about .column-card__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-2);
}

.page-about .column-card.is-hidden {
  display: none;
}

/* ---------- 产品脉络 ---------- */

.page-about .about-versions__aside,
.page-about .about-team__aside,
.page-about .about-timeline__aside {
  display: flex;
  flex-direction: column;
}

.page-about .about-versions__note,
.page-about .about-team__note,
.page-about .about-timeline__note {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  padding-left: 14px;
  border-left: 2px solid var(--gold);
}

.page-about .version-split {
  display: grid;
  gap: clamp(16px, 2.6vw, 22px);
  margin: clamp(20px, 3.2vw, 30px) 0;
}

.page-about .version-card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: clamp(20px, 3vw, 30px);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(165deg, var(--ink-2), rgba(11, 27, 43, .6));
  box-shadow: var(--shadow-card);
  transition: border-color .2s ease, transform .2s ease;
}

.page-about .version-card:hover {
  border-color: rgba(212, 162, 76, .5);
  transform: translateY(-2px);
}

.page-about .version-card--reader:hover {
  border-color: rgba(95, 168, 154, .55);
}

.page-about .version-card__name {
  margin: 0;
  font-size: 12px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--gold);
}

.page-about .version-card--reader .version-card__name {
  color: var(--celadon);
}

.page-about .version-card__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: clamp(19px, 2.2vw, 23px);
  font-weight: 700;
  color: var(--text);
}

.page-about .version-card__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-2);
}

.page-about .version-card__prices {
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .version-card__prices li {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 14px 8px;
  background: rgba(30, 58, 95, .42);
  text-align: center;
}

.page-about .version-card__term {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--text-2);
}

.page-about .version-card__price {
  font-size: clamp(24px, 3.4vw, 34px);
  line-height: 1;
  color: var(--gold-lite);
}

.page-about .version-card__unit {
  font-size: 12px;
  color: var(--text-2);
}

.page-about .about-versions__foot {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
}

/* ---------- 服务能力 ---------- */

.page-about .about-service__panel {
  padding: clamp(22px, 4vw, 48px);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(90% 120% at 100% 0%, rgba(95, 168, 154, .16), transparent 60%),
    var(--about-panel);
}

.page-about .about-service__head {
  max-width: 66ch;
  margin-bottom: clamp(20px, 3.2vw, 32px);
}

.page-about .about-service__lead {
  margin: 0;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.8;
  color: var(--text-2);
}

.page-about .about-service__list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: clamp(14px, 2.4vw, 22px);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .service-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(16px, 2.4vw, 22px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(11, 27, 43, .5);
}

.page-about .service-item__label {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--electric);
}

.page-about .service-item__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--text-2);
}

/* ---------- 团队协作 ---------- */

.page-about .about-team__figure {
  margin: clamp(22px, 3.6vw, 34px) 0 0;
}

/* ---------- 版本演进 ---------- */

.page-about .timeline {
  position: relative;
  display: grid;
  gap: clamp(14px, 2.2vw, 20px);
  margin: clamp(18px, 3vw, 28px) 0 0;
  padding: 0 0 0 clamp(18px, 2.6vw, 26px);
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold), var(--celadon), transparent);
}

.page-about .timeline__item {
  position: relative;
  padding: clamp(16px, 2.6vw, 24px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(160deg, rgba(30, 58, 95, .42), rgba(11, 27, 43, .55));
  transition: border-color .2s ease, transform .2s ease, box-shadow .2s ease;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: calc(-1 * clamp(18px, 2.6vw, 26px) - 1px);
  top: calc(clamp(16px, 2.6vw, 24px) + 8px);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--gold);
}

.page-about .timeline__item:hover,
.page-about .timeline__item:focus-visible,
.page-about .timeline__item:focus-within {
  border-color: rgba(212, 162, 76, .55);
  transform: translateY(-2px);
  box-shadow: var(--shadow-card);
  outline: none;
}

.page-about .timeline__item:hover::before,
.page-about .timeline__item:focus-visible::before {
  background: var(--gold);
}

.page-about .timeline__node {
  display: inline-block;
  margin-bottom: 10px;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--celadon);
}

.page-about .timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-heading);
  font-size: clamp(18px, 2.1vw, 22px);
  font-weight: 700;
  color: var(--text);
}

.page-about .timeline__text {
  margin: 0 0 10px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-2);
}

.page-about .timeline__hint {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--gold-lite);
  padding-top: 10px;
  border-top: 1px dashed var(--line);
}

/* ---------- 品牌承诺 ---------- */

.page-about .about-promise__panel {
  padding: clamp(24px, 4.4vw, 52px);
  border: 1px solid rgba(212, 162, 76, .32);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(80% 130% at 0% 100%, rgba(212, 162, 76, .14), transparent 62%),
    var(--ink-2);
}

.page-about .about-promise__title {
  max-width: 26ch;
}

.page-about .about-promise__text {
  margin: 0 0 clamp(20px, 3vw, 28px);
  max-width: 62ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--text-2);
}

.page-about .about-promise__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-promise__links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: clamp(16px, 2.4vw, 22px) 0 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .about-promise__links a {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text-2);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .16s ease, border-color .16s ease;
}

.page-about .about-promise__links a:hover,
.page-about .about-promise__links a:focus-visible {
  color: var(--electric);
  border-bottom-color: var(--electric);
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .version-split {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .grid--3-9 {
    grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
  }

  .page-about .grid--4-8 {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
    align-items: start;
  }

  .page-about .about-hero__title {
    max-width: 22ch;
  }

  .page-about .about-columns-section__head {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
  }

  .page-about .timeline {
    padding-left: 30px;
  }
}

@media (min-width: 1180px) {
  .page-about .about-origin__body,
  .page-about .about-team__body {
    padding-left: clamp(8px, 1.6vw, 22px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .filter-btn,
  .page-about .column-card,
  .page-about .version-card,
  .page-about .timeline__item,
  .page-about .breadcrumbs__link,
  .page-about .about-promise__links a {
    transition: none;
  }

  .page-about .version-card:hover,
  .page-about .timeline__item:hover,
  .page-about .timeline__item:focus-visible {
    transform: none;
  }
}