.page-about {
  --about-gap: clamp(20px, 3vw, 40px);
  --about-node: 8px;
  position: relative;
  isolation: isolate;
  background: var(--ink-900);
  color: var(--bone);
}

.page-about::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 72px 72px;
  opacity: .55;
}

.page-about .breadcrumb {
  padding-top: clamp(18px, 2.6vw, 32px);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--grey);
}

.page-about .breadcrumb a {
  color: var(--link);
  text-decoration: none;
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 品牌声明区 ---------- */
.page-about .about-top {
  padding-top: clamp(28px, 4vw, 52px);
}

.page-about .about-top__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 56px);
  align-items: start;
}

.page-about .about-top__lead h1 {
  margin: 12px 0 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(34px, 6vw, 62px);
  line-height: 1.04;
  letter-spacing: -0.01em;
  color: var(--bone);
  max-width: 20ch;
}

.page-about .about-top__lede {
  margin: clamp(16px, 2vw, 24px) 0 0;
  font-size: clamp(17px, 1.6vw, 20px);
  line-height: 1.65;
  color: var(--bone);
  max-width: 62ch;
  border-left: 2px solid var(--orange);
  padding-left: clamp(14px, 1.8vw, 22px);
}

.page-about .about-top__body {
  margin-top: clamp(18px, 2.2vw, 26px);
  max-width: 70ch;
}

.page-about .about-top__body p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--grey);
}

.page-about .about-top__body p:last-child {
  margin-bottom: 0;
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(24px, 3vw, 36px);
  background: var(--hairline-soft);
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
}

.page-about .about-facts .stat {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 14px clamp(12px, 1.6vw, 20px);
  background: var(--ink-900);
}

.page-about .about-facts .stat__value {
  font-family: var(--font-mono);
  font-size: clamp(24px, 3vw, 36px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--cyan);
  letter-spacing: -0.02em;
}

.page-about .about-facts .stat__label {
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--grey);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  border-top: 1px solid var(--hairline);
  padding-top: 14px;
}

.page-about .about-index__title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--grey);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-index__list li + li {
  border-top: 1px solid var(--hairline-soft);
}

.page-about .about-index__list a {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 11px 2px;
  text-decoration: none;
  color: var(--bone);
  font-size: 15px;
  transition: color .2s ease, padding-left .2s ease, background-color .2s ease;
}

.page-about .about-index__num {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--cyan);
  letter-spacing: .08em;
  transition: color .2s ease;
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  color: var(--cyan);
  padding-left: 8px;
  background: var(--ink-800);
}

.page-about .about-index__list a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

/* ---------- 首屏宽幅图 ---------- */
.page-about .about-visual {
  margin: clamp(28px, 4vw, 52px) 0 0;
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
}

.page-about .about-visual img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(.85) contrast(1.05);
}

.page-about .media__cap {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--grey);
  letter-spacing: .04em;
}

/* ---------- 通用章节头 ---------- */
.page-about .about-head {
  margin-bottom: clamp(22px, 3vw, 36px);
  border-bottom: 1px solid var(--hairline-soft);
  padding-bottom: clamp(12px, 1.6vw, 20px);
}

.page-about .about-head h2 {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(26px, 3.6vw, 40px);
  line-height: 1.12;
  letter-spacing: -0.005em;
  color: var(--bone);
}

.page-about .about-head__sub {
  margin: 10px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--grey);
}

/* ---------- 时间线 ---------- */
.page-about .about-line {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .about-line::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 9px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(34, 245, 200, .28) 30%, var(--hairline-soft) 100%);
}

.page-about .about-line__item {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: 22px 0 22px 34px;
  border-bottom: 1px solid var(--hairline-soft);
  transition: background-color .25s ease;
}

.page-about .about-line__item::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 28px;
  width: var(--about-node);
  height: var(--about-node);
  background: var(--ink-900);
  border: 1px solid var(--grey);
  transition: background-color .25s ease, border-color .25s ease, transform .25s ease;
}

.page-about .about-line__item:hover,
.page-about .about-line__item:focus-within {
  background: var(--ink-800);
}

.page-about .about-line__item:hover::before,
.page-about .about-line__item:focus-within::before {
  background: var(--cyan);
  border-color: var(--cyan);
  transform: scale(1.3);
}

.page-about .about-line__year {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-line__body h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(19px, 2vw, 23px);
  line-height: 1.25;
  color: var(--bone);
}

.page-about .about-line__body p {
  margin: 0;
  max-width: 66ch;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--grey);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--about-gap);
  align-items: start;
}

.page-about .about-team__media {
  margin: 0;
  border: 1px solid var(--hairline-soft);
}

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

.page-about .about-roles {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-roles li {
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr);
  gap: 14px;
  padding: 18px 0;
  border-top: 1px solid var(--hairline-soft);
}

.page-about .about-roles li:last-child {
  border-bottom: 1px solid var(--hairline-soft);
}

.page-about .about-roles__num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.6vw, 28px);
  font-weight: 700;
  line-height: 1.15;
  color: var(--cyan);
}

.page-about .about-roles__text h3 {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 19px;
  color: var(--bone);
}

.page-about .about-roles__text p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--grey);
}

.page-about .about-cadence {
  margin-top: 22px;
  padding: 14px clamp(14px, 1.8vw, 20px);
  background: var(--ink-700);
  border-left: 2px solid var(--orange);
}

.page-about .about-cadence p {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 16px;
  margin: 0;
  padding: 7px 0;
  font-size: 14px;
  border-bottom: 1px solid var(--hairline-soft);
}

.page-about .about-cadence p:last-child {
  border-bottom: 0;
}

.page-about .about-cadence__k {
  min-width: 76px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--grey);
  align-self: center;
}

.page-about .about-cadence__v {
  color: var(--bone);
  font-weight: 500;
}

/* ---------- 生态 ---------- */
.page-about .about-eco {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--about-gap);
  align-items: start;
}

.page-about .about-eco__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--hairline-soft);
  border: 1px solid var(--hairline-soft);
}

.page-about .about-eco__list li {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 6px 18px;
  padding: 14px clamp(14px, 1.8vw, 20px);
  background: var(--ink-900);
  transition: background-color .2s ease;
}

.page-about .about-eco__list li:hover {
  background: var(--ink-800);
}

.page-about .about-eco__k {
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--grey);
}

.page-about .about-eco__v {
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--bone);
  text-align: right;
}

.page-about .about-eco__note {
  margin: 16px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--grey);
}

.page-about .about-eco__media {
  margin: 0;
  border: 1px solid var(--hairline-soft);
}

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

/* ---------- 版本能力 ---------- */
.page-about .about-tiers {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--hairline-soft);
  border: 1px solid var(--hairline-soft);
}

.page-about .about-tier {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(20px, 2.6vw, 30px);
  background: var(--ink-900);
  border-top: 2px solid var(--ink-700);
  transition: background-color .25s ease, border-color .25s ease;
}

.page-about .about-tier:hover {
  background: var(--ink-800);
  border-top-color: var(--cyan);
}

.page-about .about-tier--focus {
  border-top-color: var(--orange);
}

.page-about .about-tier--focus:hover {
  border-top-color: var(--orange);
}

.page-about .about-tier__tag {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--cyan);
}

.page-about .about-tier--focus .about-tier__tag {
  color: var(--orange);
}

.page-about .about-tier h3 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 21px;
  color: var(--bone);
}

.page-about .about-tier p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--grey);
}

.page-about .about-honors {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: clamp(20px, 2.6vw, 30px);
  background: var(--hairline-soft);
  border: 1px solid var(--hairline-soft);
}

.page-about .about-honor {
  padding: clamp(18px, 2.2vw, 26px);
  background: var(--ink-800);
}

.page-about .about-honor__year {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--orange);
}

.page-about .about-honor h3 {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 20px;
  color: var(--bone);
}

.page-about .about-honor p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--grey);
}

.page-about .about-extras {
  margin-top: clamp(20px, 2.6vw, 30px);
  border-top: 1px solid var(--hairline-soft);
}

.page-about .about-extras p {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  margin: 0;
  padding: 14px 0;
  font-size: 15px;
  line-height: 1.7;
  border-bottom: 1px solid var(--hairline-soft);
}

.page-about .about-extras__k {
  min-width: 88px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--cyan);
  align-self: center;
}

.page-about .about-extras__v {
  flex: 1 1 240px;
  color: var(--grey);
}

/* ---------- 联系与支持 ---------- */
.page-about .about-support {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3vw, 40px);
  border-left: 2px solid var(--cyan);
}

.page-about .about-support__lead h2 {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(24px, 3.2vw, 34px);
  line-height: 1.15;
  color: var(--bone);
}

.page-about .about-support__lead p {
  margin: 12px 0 0;
  max-width: 58ch;
  font-size: 16px;
  line-height: 1.78;
  color: var(--grey);
}

.page-about .about-support__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
}

.page-about .about-support__contact {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  align-content: start;
  gap: 1px;
  background: var(--hairline-soft);
  border: 1px solid var(--hairline-soft);
}

.page-about .about-support__contact li {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 16px;
  padding: 13px clamp(14px, 1.8vw, 18px);
  background: var(--ink-700);
}

.page-about .about-support__label {
  min-width: 74px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--grey);
  align-self: center;
}

.page-about .about-support__value {
  flex: 1 1 200px;
  font-size: 15px;
  color: var(--bone);
  word-break: break-word;
}

/* ---------- 入场动效（渐进增强） ---------- */
.page-about [data-reveal] {
  opacity: 1;
}

.page-about.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .5s ease, transform .5s ease;
}

.page-about.has-js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  .page-about.has-js [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .page-about .about-line__item,
  .page-about .about-index__list a {
    transition: none;
  }
}

/* ---------- 620px 以上 ---------- */
@media (min-width: 620px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

/* ---------- 800px 以上 ---------- */
@media (min-width: 800px) {
  .page-about .about-line__item {
    grid-template-columns: 104px minmax(0, 1fr);
    gap: 26px;
    align-items: start;
  }

  .page-about .about-line__year {
    padding-top: 6px;
  }
}

/* ---------- 900px 以上 ---------- */
@media (min-width: 900px) {
  .page-about .about-team {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
    gap: clamp(28px, 3.4vw, 48px);
  }

  .page-about .about-eco {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: clamp(28px, 3.4vw, 48px);
  }

  .page-about .about-tiers {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-support {
    grid-template-columns: minmax(0, 1.25fr) minmax(260px, .95fr);
  }
}

/* ---------- 960px 以上 ---------- */
@media (min-width: 960px) {
  .page-about .about-top__grid {
    grid-template-columns: minmax(0, 1.62fr) minmax(250px, .78fr);
    gap: clamp(36px, 4.6vw, 76px);
  }

  .page-about .about-index {
    position: sticky;
    top: 104px;
  }
}