.page-about {
  --about-pad: clamp(56px, 9vw, 118px);
  --about-rule: rgba(90, 101, 114, 0.42);
  --about-rule-soft: rgba(90, 101, 114, 0.22);
  color: var(--white);
  background: var(--ink);
  display: block;
}

/* ---------- 顶部面包屑 ---------- */
.page-about .about-topbar {
  padding: calc(var(--header-h, 64px) + 18px) 0 0;
}

.page-about .breadcrumb-item:last-child {
  color: var(--cyan);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(24px, 4vw, 48px) 0 clamp(40px, 6vw, 80px);
}

.page-about .about-hero-frame {
  position: relative;
  border: 1px solid var(--about-rule);
  padding: clamp(24px, 4.5vw, 56px);
  background:
    linear-gradient(155deg, #080D14 0%, #05070A 58%, #05070A 100%);
  overflow: hidden;
}

.page-about .about-hero-frame::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 60px;
  height: 3px;
  background: var(--cyan);
}

.page-about .about-hero-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(
      0deg,
      rgba(125, 249, 255, 0.05) 0px,
      rgba(125, 249, 255, 0.05) 1px,
      transparent 1px,
      transparent 6px
    );
  pointer-events: none;
  mix-blend-mode: screen;
}

.page-about .about-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 56px);
}

.page-about .about-filetag {
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0 0 18px;
}

.page-about .about-hero h1 {
  font-family: var(--font-head);
  font-weight: 900;
  font-stretch: condensed;
  font-size: clamp(28px, 6.4vw, 52px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin: 0 0 22px;
  color: var(--white);
  max-width: 18ch;
}

.page-about .about-lede {
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.8;
  color: rgba(242, 247, 250, 0.78);
  max-width: 60ch;
  margin: 0 0 28px;
}

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

.page-about .about-hero-side {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule);
  align-self: start;
}

.page-about .about-stat {
  background: #070B11;
  padding: clamp(16px, 2.4vw, 24px);
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: background 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.page-about .about-stat:hover {
  background: #0A111A;
  box-shadow: inset 0 0 0 1px rgba(0, 229, 255, 0.35);
}

.page-about .about-stat-num {
  font-family: var(--font-data);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 700;
  color: var(--lime);
  line-height: 1;
  letter-spacing: -0.01em;
}

.page-about .about-stat-label {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: rgba(242, 247, 250, 0.6);
}

/* ---------- 品牌起源 ---------- */
.page-about .about-origin {
  padding: 0 0 var(--about-pad);
}

.page-about .about-origin-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 5vw, 64px);
  align-items: start;
}

.page-about .about-origin-media {
  margin: 0;
}

.page-about .about-origin-media .media-frame {
  border: 1px solid var(--about-rule);
  border-left: 3px solid var(--cyan);
  overflow: hidden;
}

.page-about .about-origin-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.9) contrast(1.05);
}

.page-about .about-origin-copy .section-index,
.page-about .about-credential .section-index,
.page-about .about-team .section-index,
.page-about .about-version .section-index,
.page-about .about-next .section-index {
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--cyan);
  margin: 0 0 14px;
  text-transform: uppercase;
}

.page-about .about-origin-copy .section-title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(22px, 3.6vw, 34px);
  line-height: 1.2;
  letter-spacing: -0.01em;
  margin: 0 0 20px;
  max-width: 24ch;
}

.page-about .about-origin-copy p {
  font-size: 15px;
  line-height: 1.85;
  color: rgba(242, 247, 250, 0.74);
  margin: 0 0 16px;
}

.page-about .about-points {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .about-points li {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 12px 0;
  border-bottom: 1px solid var(--about-rule-soft);
  font-size: 14px;
  line-height: 1.7;
  color: rgba(242, 247, 250, 0.82);
}

.page-about .about-point-dot {
  flex: none;
  width: 8px;
  height: 8px;
  margin-top: 7px;
  background: var(--lime);
  transform: rotate(45deg);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  padding: var(--about-pad) 0;
  border-top: 1px solid var(--about-rule-soft);
  border-bottom: 1px solid var(--about-rule-soft);
}

.page-about .section-head {
  margin-bottom: clamp(28px, 4vw, 48px);
}

.page-about .about-timeline .section-title,
.page-about .about-team .section-title,
.page-about .about-credential .section-title,
.page-about .about-next .section-title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(22px, 3.8vw, 36px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  margin: 0 0 12px;
  max-width: 26ch;
}

.page-about .section-kicker {
  font-size: 14px;
  line-height: 1.75;
  color: rgba(242, 247, 250, 0.6);
  margin: 0;
  max-width: 56ch;
}

.page-about .about-axis {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .about-axis-item {
  display: grid;
  grid-template-columns: 68px 1px minmax(0, 1fr);
  gap: 0 clamp(12px, 2vw, 24px);
  padding-bottom: clamp(24px, 3.4vw, 40px);
}

.page-about .about-axis-item:last-child {
  padding-bottom: 0;
}

.page-about .about-axis-year {
  font-family: var(--font-data);
  font-size: clamp(13px, 1.6vw, 15px);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--cyan);
  padding-top: 3px;
  white-space: nowrap;
}

.page-about .about-axis-item--current .about-axis-year {
  color: var(--lime);
}

.page-about .about-axis-line {
  display: block;
  width: 1px;
  height: 100%;
  min-height: 40px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(90, 101, 114, 0.28) 100%);
}

.page-about .about-axis-item--current .about-axis-line {
  background: linear-gradient(180deg, var(--lime) 0%, rgba(90, 101, 114, 0.28) 100%);
}

.page-about .about-axis-body {
  border: 1px solid var(--about-rule-soft);
  background: rgba(26, 32, 40, 0.5);
  padding: clamp(16px, 2.4vw, 24px);
  transition: border-color 0.25s var(--ease), background 0.25s var(--ease), transform 0.25s var(--ease);
}

.page-about .about-axis-item:hover .about-axis-body {
  border-color: rgba(0, 229, 255, 0.55);
  background: rgba(26, 32, 40, 0.78);
  transform: translateX(2px);
}

.page-about .about-axis-tag {
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--magenta);
  margin: 0 0 8px;
}

.page-about .about-axis-item--current .about-axis-tag {
  color: var(--lime);
}

.page-about .about-axis-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.35;
  margin: 0 0 8px;
  color: var(--white);
}

.page-about .about-axis-text {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(242, 247, 250, 0.7);
  margin: 0;
  max-width: 64ch;
}

/* ---------- 折叠面板 ---------- */
.page-about .about-more {
  margin-top: clamp(28px, 4vw, 44px);
  border: 1px solid var(--about-rule);
  background: #070B11;
}

.page-about .about-more > summary {
  cursor: pointer;
  list-style: none;
  padding: 16px clamp(16px, 2.4vw, 24px);
  font-family: var(--font-data);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--cyan);
  display: flex;
  align-items: center;
  gap: 12px;
  transition: background 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about .about-more > summary::-webkit-details-marker {
  display: none;
}

.page-about .about-more > summary::before {
  content: "+";
  font-family: var(--font-data);
  font-size: 16px;
  line-height: 1;
  color: var(--magenta);
}

.page-about .about-more[open] > summary::before {
  content: "−";
  color: var(--lime);
}

.page-about .about-more > summary:hover {
  background: #0B1219;
}

.page-about .about-more-body {
  padding: 0 clamp(16px, 2.4vw, 24px) 20px;
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .about-more-body p {
  font-size: 14px;
  line-height: 1.85;
  color: rgba(242, 247, 250, 0.72);
  margin: 16px 0 0;
  max-width: 70ch;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  position: relative;
  isolation: isolate;
  padding: var(--about-pad) 0;
}

.page-about .about-team::before {
  content: "";
  position: absolute;
  inset: 4% -2%;
  background: linear-gradient(180deg, #01333C 0%, #00232B 100%);
  clip-path: polygon(0 5%, 100% 0, 100% 95%, 0 100%);
  z-index: -1;
}

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

.page-about .about-team-copy > p {
  font-size: 15px;
  line-height: 1.85;
  color: rgba(242, 247, 250, 0.78);
  margin: 0 0 16px;
  max-width: 62ch;
}

.page-about .about-team-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: 26px;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule-soft);
}

.page-about .about-team-card {
  background: #06151A;
  padding: clamp(16px, 2.4vw, 22px);
  border-top: 3px solid var(--line);
  transition: background 0.25s var(--ease), transform 0.25s var(--ease);
}

.page-about .about-team-card--cyan {
  border-top-color: var(--cyan);
}

.page-about .about-team-card--magenta {
  border-top-color: var(--magenta);
}

.page-about .about-team-card--lime {
  border-top-color: var(--lime);
}

.page-about .about-team-card:hover {
  background: #0A1F26;
  transform: translateY(-2px);
}

.page-about .about-team-card-tag {
  margin: 0 0 10px;
  font-size: 11px;
}

.page-about .about-team-card-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 16px;
  line-height: 1.35;
  margin: 0 0 8px;
  color: var(--white);
}

.page-about .about-team-card-text {
  font-size: 13px;
  line-height: 1.75;
  color: rgba(242, 247, 250, 0.64);
  margin: 0;
}

.page-about .about-team-media {
  margin: 0;
}

.page-about .about-team-media .media-frame {
  border: 1px solid rgba(0, 229, 255, 0.4);
  overflow: hidden;
}

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

/* ---------- 资质与合作 ---------- */
.page-about .about-credential {
  padding: var(--about-pad) 0;
}

.page-about .about-credential-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3.6vw, 48px);
  align-items: start;
}

.page-about .about-credential-media {
  margin: 0;
}

.page-about .about-credential-media .media-frame {
  border: 1px solid var(--about-rule);
  overflow: hidden;
}

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

.page-about .about-credential-copy {
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule-soft);
}

.page-about .about-credential-card {
  background: #070B11;
  padding: clamp(18px, 2.6vw, 26px);
  transition: background 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.page-about .about-credential-card:hover {
  background: #0A121B;
  box-shadow: inset 3px 0 0 0 var(--cyan);
}

.page-about .about-credential-year {
  font-family: var(--font-data);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--lime);
  margin: 0 0 10px;
}

.page-about .about-credential-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.35;
  margin: 0 0 10px;
  color: var(--white);
}

.page-about .about-credential-text {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(242, 247, 250, 0.7);
  margin: 0;
}

/* ---------- 版本信息 ---------- */
.page-about .about-version {
  padding: 0 0 var(--about-pad);
}

.page-about .about-version-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 56px);
  border-top: 1px solid var(--about-rule-soft);
  padding-top: clamp(32px, 4.6vw, 60px);
}

.page-about .about-version-lead .section-title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(22px, 3.6vw, 34px);
  line-height: 1.2;
  letter-spacing: -0.01em;
  margin: 0 0 18px;
  max-width: 22ch;
}

.page-about .about-version-text {
  font-size: 15px;
  line-height: 1.85;
  color: rgba(242, 247, 250, 0.74);
  margin: 0 0 16px;
  max-width: 60ch;
}

.page-about .about-version-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-about .about-version-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule-soft);
}

.page-about .about-version-item {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 14px;
  background: #080D14;
  padding: clamp(16px, 2.4vw, 22px);
  transition: background 0.25s var(--ease);
}

.page-about .about-version-item:hover {
  background: #0C1620;
}

.page-about .about-version-num {
  font-family: var(--font-data);
  font-size: 20px;
  font-weight: 700;
  color: var(--magenta);
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.page-about .about-version-item-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 16px;
  line-height: 1.35;
  margin: 0 0 6px;
  color: var(--white);
}

.page-about .about-version-item-text {
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(242, 247, 250, 0.66);
  margin: 0;
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  padding: 0 0 clamp(56px, 8vw, 100px);
}

.page-about .about-next-frame {
  border: 1px solid var(--about-rule);
  border-left: 3px solid var(--magenta);
  background: linear-gradient(135deg, #0A0F16 0%, #05070A 100%);
  padding: clamp(24px, 4vw, 48px);
}

.page-about .about-next-text {
  font-size: 15px;
  line-height: 1.85;
  color: rgba(242, 247, 250, 0.74);
  margin: 0 0 26px;
  max-width: 64ch;
}

.page-about .about-next-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule-soft);
}

.page-about .about-next-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px clamp(14px, 2vw, 20px);
  background: #080D14;
  color: var(--white);
  text-decoration: none;
  font-size: 14px;
  letter-spacing: 0.01em;
  transition: background 0.22s var(--ease), color 0.22s var(--ease);
}

.page-about .about-next-link:hover {
  background: var(--cyan);
  color: var(--ink);
}

.page-about .about-next-arrow {
  font-family: var(--font-data);
  font-size: 15px;
  color: var(--cyan);
  transition: color 0.22s var(--ease), transform 0.22s var(--ease);
}

.page-about .about-next-link:hover .about-next-arrow {
  color: var(--ink);
  transform: translateX(3px);
}

/* ---------- 装饰性衬线引言 ---------- */
.page-about .about-origin-copy::after {
  content: "档案室的意义，在于任何时候都能把一份资料找回来。";
  display: block;
  margin-top: 26px;
  padding-top: 20px;
  border-top: 1px solid var(--about-rule-soft);
  font-family: var(--font-serif);
  font-style: italic;
  font-size: clamp(15px, 1.8vw, 18px);
  line-height: 1.7;
  color: rgba(125, 249, 255, 0.78);
  max-width: 44ch;
}

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

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

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(240px, 1fr);
    align-items: start;
  }

  .page-about .about-origin-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
    align-items: start;
  }

  .page-about .about-origin-media {
    position: sticky;
    top: calc(var(--header-h, 64px) + 24px);
  }

  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-credential-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
  }

  .page-about .about-version-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-axis-item {
    grid-template-columns: 90px 1px minmax(0, 1fr);
  }
}

@media (min-width: 1080px) {
  .page-about .about-hero h1 {
    font-size: clamp(34px, 4vw, 54px);
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-stat,
  .page-about .about-axis-body,
  .page-about .about-team-card,
  .page-about .about-credential-card,
  .page-about .about-version-item,
  .page-about .about-next-link,
  .page-about .about-next-arrow {
    transition: none;
  }

  .page-about .about-axis-item:hover .about-axis-body,
  .page-about .about-team-card:hover,
  .page-about .about-next-link:hover .about-next-arrow {
    transform: none;
  }
}