.page-about {
  --about-gap-lg: clamp(32px, 5vw, 72px);
  --about-gap-md: clamp(20px, 3vw, 40px);
  --about-radius: 2px;
  display: block;
}

/* 面包屑上边距 */
.page-about .breadcrumb {
  padding-top: clamp(16px, 2.5vw, 28px);
}

/* ========== 首屏 ========== */
.page-about .about-hero {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  padding-block: clamp(24px, 4vw, 48px) clamp(48px, 7vw, 96px);
}

.page-about .about-hero__text {
  position: relative;
  min-width: 0;
}

.page-about .about-hero__text h1 {
  margin: 12px 0 20px;
  font-size: clamp(38px, 7.4vw, 84px);
  line-height: 1.06;
  letter-spacing: 0.02em;
  font-weight: 900;
  color: var(--text-strong);
}

.page-about .about-hero__text .lede {
  max-width: 58ch;
  font-size: clamp(16px, 1.4vw, 18px);
  line-height: 1.75;
  color: var(--text);
  margin: 0 0 28px;
}

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

.page-about .about-hero__rule {
  margin-top: 32px;
  height: 2px;
  width: min(320px, 70%);
  background: linear-gradient(90deg, var(--blue) 0%, var(--violet) 45%, var(--cyan) 78%, var(--orange) 100%);
  border-radius: 2px;
}

.page-about .about-hero__side {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(16px, 2.4vw, 24px);
  background: var(--bg-panel);
}

.page-about .about-stat__value {
  font-size: clamp(22px, 2.6vw, 32px);
  font-weight: 700;
  color: var(--cyan);
  letter-spacing: 0.01em;
  line-height: 1.1;
}

.page-about .about-stat__label {
  font-size: 13px;
  color: var(--text-dim);
  letter-spacing: 0.02em;
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: 7fr 5fr;
    gap: clamp(40px, 5vw, 72px);
    align-items: start;
  }
  .page-about .about-hero__side {
    margin-top: 26px;
  }
}

/* ========== 通用章节 ========== */
.page-about .about-section {
  padding-block: var(--about-gap-lg);
  border-top: 1px solid var(--line);
}

.page-about .about-section__head {
  max-width: 72ch;
  margin-bottom: clamp(24px, 3.6vw, 44px);
}

.page-about .about-section__head .kicker {
  margin: 0 0 10px;
}

.page-about .about-section__head h2 {
  font-size: clamp(26px, 3.6vw, 48px);
  line-height: 1.14;
  letter-spacing: 0.015em;
  font-weight: 900;
  color: var(--text-strong);
  margin: 0 0 16px;
}

.page-about .about-section__head .lede {
  font-size: clamp(15px, 1.3vw, 17px);
  line-height: 1.75;
  color: var(--text);
  margin: 0;
}

/* ========== 演进图 ========== */
.page-about .about-journey__figure {
  margin: 0 0 clamp(28px, 4vw, 52px);
  border: 1px solid var(--line);
}

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

/* ========== 时间轴 ========== */
.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .timeline__item {
  position: relative;
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 20px;
  padding-bottom: clamp(20px, 3vw, 36px);
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: 35px;
  top: 0;
  bottom: 0;
  width: 1px;
  background: var(--line);
}

.page-about .timeline__item:first-child::before {
  top: 22px;
}

.page-about .timeline__item:last-child::before {
  bottom: calc(100% - 22px);
}

.page-about .timeline__marker {
  position: relative;
  z-index: 1;
  justify-self: center;
  margin-top: 8px;
  padding: 6px 8px;
  font-size: clamp(16px, 1.6vw, 20px);
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--cyan);
  background: var(--bg-deep);
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
  line-height: 1;
}

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

.page-about .timeline__body .panel__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 14px;
  margin-bottom: 12px;
}

.page-about .timeline__body .panel__index {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--violet);
}

.page-about .timeline__body .panel__title {
  font-size: clamp(17px, 1.7vw, 22px);
  font-weight: 700;
  color: var(--text-strong);
  margin: 0;
  line-height: 1.35;
}

.page-about .timeline__body p {
  margin: 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text);
}

@media (min-width: 760px) {
  .page-about .timeline__item {
    grid-template-columns: 104px minmax(0, 1fr);
    gap: 32px;
  }
  .page-about .timeline__item::before {
    left: 51px;
  }
}

/* ========== 服务团队 ========== */
.page-about .support-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3.2vw, 40px);
  align-items: start;
}

.page-about .support-layout__copy p {
  margin: 0 0 18px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text);
}

.page-about .support-layout__media {
  margin: 0;
  border: 1px solid var(--line);
}

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

.page-about .shift-bar {
  margin-top: 8px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 2px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .shift-bar__slot {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px 14px 16px;
  background: var(--bg-panel);
  border-top: 2px solid var(--cyan);
}

.page-about .shift-bar__slot:nth-child(2) {
  border-top-color: var(--violet);
}

.page-about .shift-bar__slot:nth-child(3) {
  border-top-color: var(--orange);
}

.page-about .shift-bar__time {
  font-size: 13px;
  color: var(--text-strong);
  letter-spacing: 0.01em;
}

.page-about .shift-bar__name {
  font-size: 12px;
  color: var(--text-dim);
  letter-spacing: 0.08em;
}

@media (min-width: 900px) {
  .page-about .support-layout {
    grid-template-columns: 6fr 5fr;
    gap: clamp(32px, 4vw, 56px);
  }
}

/* ========== 节点布局 ========== */
.page-about .infra-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3.2vw, 44px);
  align-items: start;
}

.page-about .infra-layout__media {
  margin: 0;
  border: 1px solid var(--line);
}

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

.page-about .infra-layout__copy p {
  margin: 0 0 18px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text);
}

.page-about .node-grid {
  list-style: none;
  margin: 0 0 20px;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .node-grid__item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 13px 16px;
  background: var(--bg-panel);
  font-size: 15px;
  color: var(--text-strong);
  letter-spacing: 0.02em;
}

.page-about .node-grid__dot {
  width: 7px;
  height: 7px;
  flex: 0 0 7px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(43, 245, 224, 0.14);
}

.page-about .infra-layout__link {
  margin: 0;
}

@media (min-width: 860px) {
  .page-about .infra-layout {
    grid-template-columns: 5fr 6fr;
  }
}

@media (min-width: 480px) {
  .page-about .node-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ========== 资质与安全 ========== */
.page-about .security-panel {
  padding: clamp(20px, 3vw, 36px);
}

.page-about .security-panel p {
  margin: 0 0 18px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text);
  max-width: 74ch;
}

.page-about .security-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 6px;
}

.page-about .security-tags .tag {
  padding: 7px 12px;
  font-size: 12px;
  letter-spacing: 0.04em;
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
}

.page-about .security-tags .tag--cyan {
  border-color: rgba(43, 245, 224, 0.42);
}

/* ========== 合作生态 ========== */
.page-about .partner-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin-bottom: clamp(24px, 3vw, 40px);
}

.page-about .partner-grid__cell {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(16px, 2.6vw, 26px);
  background: var(--bg-panel);
}

.page-about .partner-grid__cell:nth-child(1) .partner-grid__value {
  color: var(--cyan);
}
.page-about .partner-grid__cell:nth-child(2) .partner-grid__value {
  color: var(--cyan);
}
.page-about .partner-grid__cell:nth-child(3) .partner-grid__value {
  color: var(--violet);
}
.page-about .partner-grid__cell:nth-child(4) .partner-grid__value {
  color: var(--orange);
}

.page-about .partner-grid__value {
  font-size: clamp(22px, 2.6vw, 34px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 0.01em;
}

.page-about .partner-grid__label {
  font-size: 13px;
  color: var(--text-dim);
  letter-spacing: 0.02em;
}

.page-about .partner-notes {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(16px, 2vw, 28px);
  max-width: 96ch;
}

.page-about .partner-notes p {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--text);
}

@media (min-width: 720px) {
  .page-about .partner-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .partner-notes {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ========== 结尾入口 ========== */
.page-about .about-cta {
  padding-block: clamp(32px, 4.6vw, 72px) clamp(72px, 9vw, 128px);
  border-top: 1px solid var(--line);
}

.page-about .about-cta__head {
  max-width: 62ch;
  margin-bottom: clamp(22px, 3vw, 36px);
}

.page-about .about-cta__head .kicker {
  margin: 0 0 10px;
}

.page-about .about-cta__head h2 {
  font-size: clamp(22px, 3vw, 38px);
  line-height: 1.2;
  font-weight: 900;
  color: var(--text-strong);
  margin: 0;
  letter-spacing: 0.015em;
}

.page-about .about-cta__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-cta__card {
  display: grid;
  gap: 10px;
  padding: clamp(20px, 3vw, 30px);
  background: var(--bg-panel);
  text-decoration: none;
  color: inherit;
  border-left: 2px solid transparent;
  transition: border-color 180ms ease, background-color 180ms ease;
}

.page-about .about-cta__card:hover,
.page-about .about-cta__card:focus-visible {
  border-left-color: var(--cyan);
  background: rgba(43, 245, 224, 0.045);
}

.page-about .about-cta__label {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--violet);
}

.page-about .about-cta__title {
  font-size: clamp(16px, 1.5vw, 19px);
  color: var(--text-strong);
  font-weight: 700;
  letter-spacing: 0.01em;
}

.page-about .about-cta__desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-dim);
}

@media (min-width: 820px) {
  .page-about .about-cta__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ========== 窄屏保护 ========== */
@media (max-width: 480px) {
  .page-about .about-stat {
    padding: 14px 12px;
  }
  .page-about .shift-bar__slot {
    padding: 12px 10px 14px;
  }
  .page-about .shift-bar__time {
    font-size: 11px;
  }
  .page-about .shift-bar__name {
    font-size: 11px;
  }
  .page-about .timeline__item {
    grid-template-columns: 58px minmax(0, 1fr);
    gap: 14px;
  }
  .page-about .timeline__item::before {
    left: 28px;
  }
}

/* ========== 动效降级 ========== */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-cta__card {
    transition: none;
  }
}
</main>