.page-about {
  --about-rail: 96px;
  --about-gap: clamp(20px, 4vw, 56px);
  display: block;
  background:
    repeating-linear-gradient(90deg, transparent 0 79px, rgba(168, 225, 245, 0.035) 79px 80px),
    var(--ms-ink);
  color: var(--ms-frost);
  padding-bottom: clamp(48px, 8vw, 96px);
  overflow-x: hidden;
}

.page-about .about-crumbs {
  max-width: var(--ms-max);
  margin-inline: auto;
  padding: clamp(16px, 3vw, 28px) var(--ms-gutter) 0;
}

.page-about .ms-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ms-mist);
}

.page-about .ms-crumbs__item + .ms-crumbs__item::before {
  content: "/";
  margin-right: 0.5rem;
  color: rgba(168, 225, 245, 0.4);
}

.page-about .ms-crumbs__link {
  color: var(--ms-ice-pale);
  text-decoration: none;
}

.page-about .ms-crumbs__link:hover {
  color: var(--ms-ice);
  text-decoration: underline;
}

/* 标题区 */
.page-about .about-hero {
  padding: clamp(32px, 6vw, 76px) var(--ms-gutter) clamp(24px, 4vw, 48px);
}

.page-about .about-hero__inner {
  max-width: 1040px;
  margin-inline: auto;
  text-align: center;
}

.page-about .about-hero .ms-index {
  color: var(--ms-ice);
  margin-bottom: clamp(14px, 2vw, 24px);
}

.page-about .about-hero__title {
  font-family: var(--ms-font-display);
  font-weight: 200;
  font-size: clamp(2.3rem, 8.4vw, 5.6rem);
  line-height: 1.02;
  letter-spacing: -0.02em;
  margin: 0 0 clamp(18px, 3vw, 32px);
  color: var(--ms-frost);
}

.page-about .about-hero__lede {
  max-width: 44em;
  margin-inline: auto;
  color: var(--ms-mist);
  font-size: clamp(0.95rem, 1.6vw, 1.06rem);
  line-height: 1.75;
}

.page-about .about-hero__lede p {
  margin: 0;
}

.page-about .about-hero__lede p + p {
  margin-top: 0.6em;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  max-width: 560px;
  margin: clamp(24px, 4vw, 40px) auto 0;
  border: 1px solid var(--ms-line);
  background: var(--ms-line);
  margin-bottom: 0;
}

.page-about .about-hero__stat {
  background: var(--ms-ink-2);
  padding: clamp(12px, 2vw, 20px) 8px;
  margin: 0;
}

.page-about .about-hero__stat-label {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--ms-mist);
  text-transform: uppercase;
}

.page-about .about-hero__stat-num {
  margin: 6px 0 0;
  font-family: var(--ms-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.5rem, 4.4vw, 2.3rem);
  line-height: 1;
  color: var(--ms-red);
  letter-spacing: -0.02em;
}

.page-about .about-hero__stat-num span {
  font-family: var(--ms-font-sans);
  font-size: 0.42em;
  color: var(--ms-mist);
  margin-left: 3px;
  letter-spacing: 0;
}

/* 通栏横幅 */
.page-about .about-banner {
  position: relative;
  margin: 0 auto;
  max-width: 1600px;
  overflow: hidden;
  border-top: 1px solid var(--ms-line-strong);
}

.page-about .about-banner img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 440px;
  object-fit: cover;
  filter: saturate(0.85) contrast(1.05);
}

.page-about .about-banner::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 52%;
  background: linear-gradient(180deg, rgba(11, 13, 16, 0) 0%, var(--ms-ink) 96%);
  pointer-events: none;
}

/* 章节索引条 */
.page-about .about-toc {
  display: flex;
  gap: 8px;
  align-items: center;
  max-width: var(--ms-max);
  margin-inline: auto;
  padding: clamp(16px, 3vw, 26px) var(--ms-gutter);
  overflow-x: auto;
  border-bottom: 1px solid var(--ms-line);
  scrollbar-width: thin;
}

.page-about .about-toc__item {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--ms-line);
  border-radius: 999px;
  color: var(--ms-mist);
  font-size: 12px;
  letter-spacing: 0.1em;
  text-decoration: none;
  transition: border-color 0.2s ease, color 0.2s ease, background-color 0.2s ease;
}

.page-about .about-toc__item span {
  font-family: var(--ms-font-mono);
  font-size: 11px;
  color: var(--ms-red);
}

.page-about .about-toc__item:hover {
  border-color: var(--ms-ice);
  color: var(--ms-ice-pale);
  background: rgba(88, 200, 240, 0.07);
}

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

/* 章节骨架 */
.page-about .about-chapter {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  max-width: var(--ms-max);
  margin-inline: auto;
  padding: clamp(40px, 6vw, 82px) var(--ms-gutter);
  border-bottom: 1px solid var(--ms-line);
  scroll-margin-top: 96px;
}

.page-about .about-chapter__rail {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 14px;
}

.page-about .about-chapter__num {
  font-family: var(--ms-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(26px, 4vw, 40px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ms-red);
}

.page-about .about-chapter__line {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--ms-line-strong), transparent);
}

.page-about .about-chapter__body .ms-index {
  color: var(--ms-ice-pale);
  margin-bottom: 10px;
}

.page-about .about-chapter h2 {
  font-size: clamp(1.45rem, 3.2vw, 2.2rem);
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.01em;
  margin: 0 0 clamp(14px, 2vw, 22px);
  color: var(--ms-frost);
}

.page-about .ms-prose p {
  color: var(--ms-mist);
  line-height: 1.78;
  margin: 0 0 1em;
}

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

.page-about .ms-prose a {
  color: var(--ms-ice);
  text-decoration: none;
  border-bottom: 1px solid rgba(88, 200, 240, 0.45);
}

.page-about .ms-prose a:hover {
  color: var(--ms-ice-pale);
  border-bottom-color: var(--ms-ice-pale);
}

/* 生产流程 */
.page-about .about-steps {
  list-style: none;
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
}

.page-about .about-steps li {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  padding: 18px 0;
  border-top: 1px solid var(--ms-line);
}

.page-about .about-steps li:last-child {
  border-bottom: 1px solid var(--ms-line);
}

.page-about .about-steps__time {
  font-family: var(--ms-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ms-ice);
}

.page-about .about-steps h3 {
  font-size: 1.02rem;
  font-weight: 700;
  margin: 0 0 6px;
  color: var(--ms-frost);
}

.page-about .about-steps p {
  margin: 0;
  color: var(--ms-mist);
  font-size: 0.94rem;
  line-height: 1.72;
}

.page-about .about-after {
  margin-top: clamp(16px, 2.5vw, 24px);
}

/* 内文图 */
.page-about .about-inline-figure {
  margin: clamp(24px, 4vw, 36px) 0 0;
  border: 1px solid var(--ms-line-strong);
  border-radius: var(--ms-radius);
  overflow: hidden;
  background: var(--ms-graphite);
}

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

.page-about .about-inline-figure figcaption {
  padding: 10px 16px;
  border-top: 1px solid var(--ms-line);
  font-family: var(--ms-font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ms-mist);
}

.page-about .about-inline-figure--end {
  margin-top: clamp(28px, 4vw, 44px);
}

/* 团队 */
.page-about .about-team {
  display: grid;
  gap: clamp(20px, 4vw, 40px);
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .about-silhouettes {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(30px, 1fr));
  gap: 16px 10px;
  align-content: start;
  padding: 26px 20px 20px;
  background: var(--ms-ink-2);
  border: 1px solid var(--ms-line);
  border-radius: var(--ms-radius);
}

.page-about .about-figure {
  position: relative;
  display: block;
  width: 18px;
  height: 24px;
  margin: 8px auto 0;
  border-radius: 5px 5px 2px 2px;
  background: currentColor;
  opacity: 0.85;
}

.page-about .about-figure::before {
  content: "";
  position: absolute;
  top: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: currentColor;
}

.page-about .about-figure--data {
  color: var(--ms-ice);
}

.page-about .about-figure--video {
  color: var(--ms-red);
}

.page-about .about-figure--ops {
  color: var(--ms-mist);
}

.page-about .about-figure--tech {
  color: var(--ms-ice-pale);
}

.page-about .about-roles {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .about-role {
  position: relative;
  padding: 16px 18px 18px;
  background: var(--ms-graphite);
  border: 1px solid var(--ms-line);
  border-radius: var(--ms-radius);
  transition: transform 0.22s ease, border-color 0.22s ease;
}

.page-about .about-role:hover {
  transform: translateY(-4px);
  border-color: var(--ms-ice);
}

.page-about .about-role__count {
  margin: 0;
  font-family: var(--ms-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.9rem;
  line-height: 1;
  color: var(--ms-ice-pale);
}

.page-about .about-role__name {
  margin: 8px 0 8px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--ms-frost);
}

.page-about .about-role__body {
  margin: 0;
  font-size: 0.87rem;
  line-height: 1.7;
  color: var(--ms-mist);
}

/* 栏目节奏 */
.page-about .about-rhythm {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .about-rhythm__col {
  padding: 18px 18px 20px;
  border: 1px solid var(--ms-line);
  border-left: 2px solid var(--ms-red);
  border-radius: 0 var(--ms-radius) var(--ms-radius) 0;
  background: var(--ms-ink-2);
}

.page-about .about-rhythm__col--alt {
  border-left-color: var(--ms-ice);
}

.page-about .about-rhythm__col .ms-index {
  color: var(--ms-mist);
  margin-bottom: 14px;
}

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

.page-about .about-rhythm__list li {
  position: relative;
  padding-left: 16px;
  margin-bottom: 10px;
  font-size: 0.9rem;
  line-height: 1.65;
  color: var(--ms-frost);
}

.page-about .about-rhythm__list li:last-child {
  margin-bottom: 0;
}

.page-about .about-rhythm__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 6px;
  height: 1px;
  background: var(--ms-ice);
}

/* 技术底座 */
.page-about .about-tech {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 44px);
  align-items: center;
  margin-top: clamp(16px, 2.5vw, 24px);
}

.page-about .about-nodes {
  position: relative;
  width: 100%;
  max-width: 380px;
  margin-inline: auto;
  aspect-ratio: 1 / 1;
}

.page-about .about-nodes__svg {
  display: block;
  width: 100%;
  height: 100%;
}

.page-about .about-nodes__ring {
  fill: none;
  stroke: var(--ms-line-strong);
  stroke-width: 1;
}

.page-about .about-nodes__dot {
  fill: var(--ms-ice);
}

.page-about .about-nodes__core {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  text-align: center;
}

.page-about .about-nodes__core-num {
  font-family: var(--ms-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.8rem, 5vw, 2.6rem);
  line-height: 1;
  color: var(--ms-red);
}

.page-about .about-nodes__core-label {
  font-size: 11px;
  letter-spacing: 0.14em;
  line-height: 1.6;
  color: var(--ms-mist);
}

/* 数据来源 */
.page-about .about-sources {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: clamp(20px, 3vw, 32px);
  background: var(--ms-line);
  border: 1px solid var(--ms-line);
}

.page-about .about-source {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 16px 18px;
  background: var(--ms-ink-2);
}

.page-about .about-source__num {
  font-family: var(--ms-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.3rem, 3vw, 1.7rem);
  line-height: 1;
  color: var(--ms-ice-pale);
  min-width: 3.2em;
}

.page-about .about-source__name {
  font-size: 0.88rem;
  letter-spacing: 0.02em;
  color: var(--ms-mist);
}

/* 时间线 */
.page-about .about-timeline {
  list-style: none;
  position: relative;
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0 0 0 30px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--ms-red), var(--ms-line-strong) 45%, transparent);
}

.page-about .about-timeline li {
  position: relative;
  padding-bottom: clamp(22px, 3vw, 30px);
}

.page-about .about-timeline li::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 5px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 1px solid var(--ms-ice);
  background: var(--ms-ink);
  transition: background-color 0.22s ease, box-shadow 0.22s ease;
}

.page-about .about-timeline li:hover::before {
  background: var(--ms-ice);
  box-shadow: 0 0 0 5px rgba(88, 200, 240, 0.14);
}

.page-about .about-timeline__stage {
  display: inline-block;
  margin-bottom: 6px;
  padding: 3px 10px;
  border: 1px solid var(--ms-line-strong);
  border-radius: 999px;
  font-family: var(--ms-font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--ms-ice);
}

.page-about .about-timeline h3 {
  margin: 0 0 6px;
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--ms-frost);
}

.page-about .about-timeline p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.72;
  color: var(--ms-mist);
  max-width: 34em;
}

/* 结尾引导 */
.page-about .about-cta {
  max-width: var(--ms-max);
  margin: clamp(36px, 6vw, 72px) auto 0;
  padding-inline: var(--ms-gutter);
}

.page-about .about-cta__inner {
  position: relative;
  padding: clamp(26px, 4vw, 44px) clamp(20px, 4vw, 48px);
  background:
    linear-gradient(115deg, rgba(58, 7, 16, 0.9) 0%, rgba(18, 22, 28, 0.96) 62%),
    var(--ms-ink-2);
  border: 1px solid var(--ms-line-strong);
  border-radius: var(--ms-radius);
  overflow: hidden;
}

.page-about .about-cta__inner::before {
  content: "";
  position: absolute;
  top: -40%;
  right: -10%;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(88, 200, 240, 0.16) 0%, transparent 68%);
  pointer-events: none;
}

.page-about .about-cta .ms-index {
  color: var(--ms-ice-pale);
  margin-bottom: 12px;
}

.page-about .about-cta__title {
  position: relative;
  margin: 0 0 12px;
  font-size: clamp(1.3rem, 3vw, 1.9rem);
  font-weight: 700;
  line-height: 1.32;
  color: var(--ms-frost);
}

.page-about .about-cta__text {
  position: relative;
  max-width: 34em;
  margin: 0 0 clamp(18px, 3vw, 26px);
  font-size: 0.94rem;
  line-height: 1.75;
  color: var(--ms-mist);
}

.page-about .about-cta__actions {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* 返回顶部 */
.page-about .about-top {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  width: max-content;
  max-width: 100%;
  margin: clamp(32px, 5vw, 56px) auto 0;
  padding: 10px 22px;
  font-family: var(--ms-font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--ms-ice);
  text-decoration: none;
  border-top: 1px solid var(--ms-line-strong);
  border-bottom: 1px solid var(--ms-line-strong);
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about .about-top span {
  color: var(--ms-red);
  font-weight: 700;
}

.page-about .about-top:hover {
  color: var(--ms-ice-pale);
  border-color: var(--ms-ice);
}

.page-about .about-top:focus-visible,
.page-about .ms-btn:focus-visible,
.page-about .about-role:focus-within {
  outline: 2px solid var(--ms-ice);
  outline-offset: 3px;
}

@media (min-width: 640px) {
  .page-about .about-roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .about-source {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .page-about .about-source__num {
    min-width: 0;
  }
}

@media (min-width: 820px) {
  .page-about .about-chapter {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
  }

  .page-about .about-chapter__rail {
    position: sticky;
    top: 104px;
    align-self: start;
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .page-about .about-chapter__line {
    width: 1px;
    height: auto;
    flex: 1;
    min-height: 88px;
    background: linear-gradient(180deg, var(--ms-line-strong), transparent);
  }

  .page-about .about-steps li {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: 20px;
    align-items: start;
  }

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

  .page-about .about-tech {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  }
}

@media (min-width: 960px) {
  .page-about .about-team {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    align-items: start;
  }

  .page-about .about-inline-figure {
    margin-top: clamp(28px, 3vw, 40px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-role,
  .page-about .about-toc__item,
  .page-about .about-timeline li::before {
    transition: none;
  }

  .page-about .about-role:hover {
    transform: none;
  }
}