.page-about {
  --about-rail: 172px;
  --about-gap: clamp(20px, 3.5vw, 56px);
  --about-line: rgba(233, 236, 239, 0.12);
  display: block;
  padding-block: clamp(18px, 3.5vw, 36px) clamp(56px, 9vw, 128px);
  color: var(--c-text);
  background-color: var(--c-ink);
  background-image:
    linear-gradient(180deg, rgba(14, 59, 54, 0.66) 0%, rgba(14, 59, 54, 0) 400px),
    repeating-linear-gradient(90deg, transparent 0 55px, rgba(233, 236, 239, 0.03) 55px 56px);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  margin-inline: calc(var(--pad) * -1);
  padding: clamp(22px, 3.6vw, 42px) var(--pad) clamp(26px, 4vw, 48px);
  border-top: 1px solid rgba(47, 243, 217, 0.28);
  border-bottom: 1px solid var(--about-line);
  background-image: linear-gradient(158deg, rgba(14, 59, 54, 0.9) 0%, rgba(11, 13, 16, 0.35) 72%);
}

.page-about .about-hero__kicker {
  margin: 0;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--c-text-2);
  text-transform: uppercase;
}

.page-about .about-hero h1 {
  margin: 16px 0 0;
  font-size: clamp(27px, 5.4vw, 48px);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.025em;
  max-width: 22ch;
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  font-size: clamp(16px, 1.9vw, 19px);
  line-height: 1.85;
  color: rgba(233, 236, 239, 0.86);
  max-width: 62ch;
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(26px, 3.4vw, 40px) 0 0;
  padding: 0;
  list-style: none;
  background: rgba(233, 236, 239, 0.14);
  border: 1px solid rgba(233, 236, 239, 0.14);
}

.page-about .about-hero__fact {
  min-width: 0;
  padding: 16px clamp(14px, 2vw, 22px) 18px;
  background: rgba(11, 13, 16, 0.62);
}

.page-about .about-hero__num {
  display: block;
  font-family: var(--mono);
  font-size: clamp(24px, 4.4vw, 38px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-hero__label {
  display: block;
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.55;
  color: var(--c-text-2);
}

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

/* ---------- 章节骨架 ---------- */

.page-about .about-chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(12px, 2vw, 22px);
  padding-block: clamp(42px, 6.4vw, 88px);
  border-top: 1px solid var(--about-line);
}

.page-about .about-chapter:first-of-type {
  border-top: 0;
}

.page-about .about-chapter__rail {
  display: flex;
  align-items: baseline;
  gap: 14px;
  min-width: 0;
}

.page-about .about-chapter__num {
  font-family: var(--mono);
  font-size: clamp(38px, 6vw, 66px);
  font-weight: 700;
  line-height: 0.82;
  letter-spacing: -0.05em;
  color: var(--c-red);
  font-variant-numeric: tabular-nums;
}

.page-about .about-chapter__label {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--c-text-2);
}

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

.page-about .about-chapter__body > h2 {
  margin: 0 0 16px;
  font-size: clamp(21px, 3.3vw, 32px);
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.02em;
  max-width: 26ch;
}

.page-about .about-chapter__body > p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(233, 236, 239, 0.74);
  max-width: 66ch;
}

@media (min-width: 900px) {
  .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: calc(var(--strip-h) + 26px);
    align-self: start;
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
}

/* ---------- 三要点 ---------- */

.page-about .about-points {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border-top: 1px solid var(--about-line);
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-points li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 16px 0;
  background: var(--c-ink);
}

.page-about .about-points__idx {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--c-red);
  padding-top: 5px;
}

.page-about .about-points__text {
  font-size: 15px;
  line-height: 1.8;
  color: rgba(233, 236, 239, 0.78);
}

.page-about .about-points__text strong {
  color: var(--c-text);
  font-weight: 700;
}

/* ---------- 时间线 ---------- */

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 28px 0 0;
  padding: 0 0 0 30px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 14px;
  width: 1px;
  background: linear-gradient(180deg, rgba(47, 243, 217, 0.4) 0%, rgba(233, 236, 239, 0.08) 100%);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: clamp(22px, 3vw, 34px);
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 5px;
  width: 11px;
  height: 11px;
  box-sizing: border-box;
  border-radius: 50%;
  background: var(--c-ink);
  border: 1px solid var(--line-strong);
  box-shadow: 0 0 0 4px var(--c-ink);
  transition: border-color 200ms ease, transform 200ms ease;
}

.page-about .timeline__item:hover::before,
.page-about .timeline__item:focus-within::before {
  border-color: var(--c-cyan);
  transform: scale(1.18);
}

.page-about .timeline__item--now::before {
  background: var(--c-red);
  border-color: var(--c-red);
}

.page-about .timeline__stage {
  margin: 0;
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--c-text-2);
}

.page-about .timeline__item--now .timeline__stage {
  color: var(--c-cyan);
}

.page-about .timeline__title {
  margin: 7px 0 8px;
  font-size: 17px;
  font-weight: 800;
  line-height: 1.45;
  letter-spacing: -0.01em;
}

.page-about .timeline__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(233, 236, 239, 0.6);
  max-width: 58ch;
  transition: color 200ms ease;
}

.page-about .timeline__item:hover .timeline__text,
.page-about .timeline__item:focus-within .timeline__text {
  color: rgba(233, 236, 239, 0.92);
}

.page-about .timeline__item:focus-visible {
  outline: 2px solid var(--c-cyan);
  outline-offset: 4px;
}

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: clamp(28px, 4.4vw, 52px) 0 0;
}

.page-about .about-figure .figure__frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--about-line);
  background: var(--c-plate);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  filter: saturate(0.86) brightness(0.74);
}

.page-about .about-figure .figure__cap {
  margin: 12px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--c-text-2);
  max-width: 60ch;
}

.page-about .about-figure--square {
  margin-top: 26px;
}

/* ---------- 团队标签页 ---------- */

.page-about .about-tabs {
  margin-top: 26px;
}

.page-about .about-tabs__buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
}

.page-about .about-tabs .tab {
  appearance: none;
  display: inline-flex;
  align-items: baseline;
  gap: 9px;
  padding: 10px 16px;
  border: 1px solid var(--line-strong);
  background: transparent;
  color: var(--c-text-2);
  font-family: var(--sans);
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  transition: color 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.page-about .about-tabs .tab:hover {
  color: var(--c-text);
  border-color: rgba(47, 243, 217, 0.42);
}

.page-about .about-tabs .tab:focus-visible {
  outline: 2px solid var(--c-cyan);
  outline-offset: 2px;
}

.page-about .about-tabs .tab[aria-selected="true"] {
  color: var(--c-text);
  background: rgba(200, 16, 46, 0.18);
  border-color: var(--c-red);
}

.page-about .about-tabs .tab__num {
  font-family: var(--mono);
  font-size: 15px;
  font-weight: 700;
  color: var(--c-cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-tabs .panel {
  border: 1px solid var(--about-line);
  border-left: 2px solid var(--c-wine);
  background: var(--c-plate);
  padding: clamp(20px, 3vw, 32px);
}

.page-about .about-tabs .panel + .panel {
  margin-top: 16px;
}

.page-about .about-tabs .panel[hidden] {
  display: none;
}

.page-about .about-tabs .panel h3 {
  margin: 0 0 10px;
  font-size: 18px;
  font-weight: 800;
  line-height: 1.45;
  letter-spacing: -0.01em;
}

.page-about .about-tabs .panel p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(233, 236, 239, 0.74);
  max-width: 62ch;
}

.page-about .about-tabs .panel ul {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-tabs .panel li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(233, 236, 239, 0.68);
}

.page-about .about-tabs .panel li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 9px;
  height: 1px;
  background: var(--c-red);
}

/* ---------- 流程 ---------- */

.page-about .flow-block {
  margin-top: 26px;
}

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

.page-about .flow__step {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(14px, 2.2vw, 28px);
  align-items: start;
  padding: 20px clamp(16px, 2.6vw, 28px) 22px;
  background: var(--c-plate);
  position: relative;
}

.page-about .flow__step::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, rgba(200, 16, 46, 0.85), rgba(126, 12, 30, 0.15));
}

.page-about .flow__idx {
  font-family: var(--mono);
  font-size: clamp(22px, 3.2vw, 30px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-red);
  font-variant-numeric: tabular-nums;
}

.page-about .flow__title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 800;
  line-height: 1.45;
  letter-spacing: -0.01em;
}

.page-about .flow__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(233, 236, 239, 0.7);
  max-width: 58ch;
}

/* ---------- 覆盖范围 ---------- */

.page-about .about-coverage {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 32px);
  margin-top: 26px;
}

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

.page-about .about-coverage__stats li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px clamp(16px, 2.2vw, 22px);
  background: var(--c-plate);
}

.page-about .about-coverage__num {
  flex: 0 0 auto;
  min-width: 5.2ch;
  font-family: var(--mono);
  font-size: clamp(20px, 2.8vw, 27px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--c-cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-coverage__label {
  font-size: 14px;
  line-height: 1.6;
  color: var(--c-text-2);
}

.page-about .about-coverage .about-figure {
  margin-top: 0;
}

@media (min-width: 900px) {
  .page-about .about-coverage {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
    align-items: start;
  }

  .page-about .flow-block {
    display: grid;
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .about-figure--square {
    margin-top: 0;
  }
}

/* ---------- 承诺 ---------- */

.page-about .promise {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .promise__item {
  position: relative;
  padding: clamp(20px, 2.8vw, 30px);
  background: linear-gradient(180deg, rgba(14, 59, 54, 0.42) 0%, rgba(20, 24, 29, 0.96) 100%);
}

.page-about .promise__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 38px;
  height: 2px;
  background: var(--c-red);
}

.page-about .promise__idx {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--c-cyan);
}

.page-about .promise__title {
  margin: 10px 0 10px;
  font-size: 18px;
  font-weight: 800;
  line-height: 1.4;
  letter-spacing: -0.01em;
}

.page-about .promise__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(233, 236, 239, 0.74);
}

/* ---------- 收束 ---------- */

.page-about .about-cta {
  margin-top: clamp(26px, 3.6vw, 42px);
  padding-top: clamp(22px, 3vw, 32px);
  border-top: 1px solid rgba(47, 243, 217, 0.24);
}

.page-about .about-cta__text {
  margin: 0 0 22px;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(233, 236, 239, 0.78);
  max-width: 66ch;
}

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

@media (min-width: 760px) {
  .page-about .promise {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 动效 ---------- */

@media (prefers-reduced-motion: reduce) {
  .page-about .timeline__item::before,
  .page-about .timeline__text,
  .page-about .about-tabs .tab {
    transition: none;
  }

  .page-about .timeline__item:hover::before,
  .page-about .timeline__item:focus-within::before {
    transform: none;
  }
}