.page-about {
  --about-gap: clamp(48px, 7vw, 96px);
  background: var(--ink);
  color: var(--paper);
  overflow-x: hidden;
}

.page-about .breadcrumb {
  padding: 16px 0 4px;
}

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .breadcrumb__list > li + li::before {
  content: "/";
  margin-right: 10px;
  color: var(--line-strong);
}

.page-about .breadcrumb__link {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--ease), border-color var(--ease);
}

.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--mint);
  border-bottom-color: var(--mint);
}

.page-about h1,
.page-about h2,
.page-about h3 {
  margin: 0;
  line-height: 1.1;
  letter-spacing: 0.05em;
}

/* ---------- 首屏 ---------- */

.about-hero {
  padding: clamp(20px, 3vw, 36px) 0 clamp(24px, 4vw, 44px);
}

.about-hero__grid {
  display: grid;
  gap: clamp(26px, 4vw, 46px);
  align-items: end;
}

.about-hero__lead h1 {
  margin: 14px 0 0;
  font-size: clamp(32px, 6.4vw, 76px);
  font-weight: 900;
  letter-spacing: 0.04em;
}

.about-hero__lead h1 em {
  display: block;
  font-style: normal;
  color: var(--mint);
}

.about-hero__text {
  margin: 20px 0 0;
  max-width: 38rem;
  font-size: 16px;
  line-height: 1.85;
  color: var(--paper-soft);
}

.about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.about-hero__panel {
  position: relative;
  background: var(--panel);
  border: 2px solid var(--line-strong);
  box-shadow: var(--shadow-hard);
  padding: 20px 20px 8px;
}

.about-hero__panel::before {
  content: "";
  position: absolute;
  top: -2px;
  left: -2px;
  width: 62px;
  height: 6px;
  background: var(--red);
}

.about-hero__panel-title {
  margin: 6px 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--mist);
  text-transform: uppercase;
}

.about-fact {
  display: grid;
  gap: 2px;
  padding: 12px 0 14px;
  border-top: 1px solid var(--line);
}

.about-fact__num {
  font-family: var(--font-mono);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  line-height: 1;
  color: var(--mint);
}

.about-fact__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
}

.about-hero__strip {
  margin-top: clamp(26px, 4vw, 44px);
}

.about-hero__strip img {
  display: block;
  width: 100%;
  height: auto;
  border: 2px solid var(--line-strong);
  box-shadow: var(--shadow-hard-sm);
  object-fit: cover;
}

/* ---------- 章节通用 ---------- */

.page-about .section {
  padding: clamp(40px, 6vw, 88px) 0;
}

.about-head {
  display: grid;
  gap: 12px;
  margin-bottom: clamp(26px, 4vw, 46px);
  max-width: 52rem;
}

.about-head h2 {
  font-size: clamp(25px, 4.2vw, 46px);
  font-weight: 900;
}

.about-head p {
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--paper-soft);
}

/* ---------- 时间线 ---------- */

.tl {
  margin: 0;
  padding: 0;
  list-style: none;
  border-bottom: 2px solid var(--line);
}

.tl__item {
  display: grid;
  gap: 8px;
  padding: clamp(20px, 3vw, 30px) 0;
  border-top: 2px solid var(--line);
  transition: border-color var(--ease), background-color var(--ease);
}

.tl__item:hover,
.tl__item:focus-visible {
  border-top-color: var(--mint);
  outline: none;
}

.tl__item:focus-visible {
  outline: 2px solid var(--mint);
  outline-offset: 6px;
}

.tl__year {
  font-family: var(--font-mono);
  font-size: clamp(38px, 6vw, 72px);
  font-weight: 700;
  line-height: 0.95;
  letter-spacing: 0.03em;
  color: var(--mint);
  transition: color var(--ease);
}

.tl__item:hover .tl__year,
.tl__item:focus-visible .tl__year {
  color: var(--amber);
}

.tl__body h3 {
  font-size: clamp(18px, 2.4vw, 24px);
  font-weight: 700;
  margin-bottom: 8px;
}

.tl__body p {
  margin: 0;
  max-width: 42rem;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

.about-timeline__more {
  margin: 26px 0 0;
}

.page-about .text-link {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid var(--teal);
  padding-bottom: 2px;
  transition: color var(--ease), border-color var(--ease);
}

.page-about .text-link:hover,
.page-about .text-link:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--red);
}

/* ---------- 数据方法 ---------- */

.about-method__grid {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  align-items: start;
}

.about-method__chart {
  background: var(--ink-2);
  border: 2px solid var(--line-strong);
  box-shadow: var(--shadow-hard-sm);
  padding: clamp(12px, 2vw, 22px);
}

.val-svg {
  display: block;
  width: 100%;
  height: auto;
}

.val__node circle {
  transition: fill var(--ease), stroke var(--ease);
}

.val__node text {
  transition: fill var(--ease);
}

.val__node:hover circle {
  fill: var(--mint);
  stroke: var(--paper);
}

.val__node:hover text {
  fill: var(--ink);
}

.method-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 18px;
}

.method-list__item {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 0;
  border-top: 2px solid var(--line);
  transition: border-color var(--ease);
}

.method-list__item:hover {
  border-top-color: var(--mint);
}

.method-list__num {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--amber);
  letter-spacing: 0.08em;
  padding-top: 3px;
}

.method-list__item h3 {
  font-size: 18px;
  margin-bottom: 6px;
}

.method-list__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--mist);
}

.about-photo {
  margin: clamp(26px, 4vw, 44px) 0 0;
  background: var(--panel);
  border: 2px solid var(--line-strong);
  box-shadow: var(--shadow-hard);
}

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

.about-photo figcaption {
  padding: 10px 14px;
  border-top: 2px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

/* ---------- 团队 ---------- */

.about-team__grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
  align-items: start;
}

.team-bar {
  padding: 14px 0 16px;
  border-top: 2px solid var(--line);
  transition: border-color var(--ease);
}

.team-bar:hover {
  border-top-color: var(--mint);
}

.team-bar__label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  margin: 0 0 10px;
  font-size: 15px;
  font-weight: 700;
}

.team-bar__count {
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--mint);
  letter-spacing: 0.06em;
}

.team-bar__track {
  height: 16px;
  background: var(--ink-2);
  border: 2px solid var(--line-strong);
  overflow: hidden;
}

.team-bar__fill {
  height: 100%;
  transition: filter var(--ease);
}

.team-bar:hover .team-bar__fill {
  filter: brightness(1.25);
}

.team-bar__fill--ops {
  width: 45.8%;
  background: var(--red);
}

.team-bar__fill--edit {
  width: 33.3%;
  background: var(--mint);
}

.team-bar__fill--care {
  width: 20.9%;
  background: var(--amber);
}

.team-bar__note {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

.about-team__grid .about-photo {
  margin-top: 0;
}

/* ---------- 合作生态 ---------- */

.about-partners__grid {
  display: grid;
  gap: 18px;
}

.partner-card {
  background: var(--ink-2);
  border: 2px solid var(--line);
  border-left: 6px solid var(--teal);
  padding: 20px;
  transition: transform var(--ease), border-color var(--ease), box-shadow var(--ease);
}

.partner-card:hover {
  transform: translateY(-3px);
  border-color: var(--mint);
  border-left-color: var(--red);
  box-shadow: var(--shadow-hard-sm);
}

.partner-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.partner-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--mist);
}

.partner-card p + p {
  margin-top: 12px;
}

.partner-card--note {
  background: var(--panel);
  border-left-color: var(--amber);
}

.partner-card--note h3 {
  color: var(--amber);
}

/* ---------- 规模 ---------- */

.stat-grid {
  display: grid;
  gap: 1px;
  background: var(--line-strong);
  border: 2px solid var(--line-strong);
}

.about-stat {
  background: var(--ink-2);
  padding: 22px 18px;
  display: grid;
  gap: 6px;
}

.about-stat__num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 4vw, 40px);
  font-weight: 700;
  line-height: 1;
  color: var(--mint);
  letter-spacing: 0.03em;
}

.about-stat:nth-child(2) .about-stat__num {
  color: var(--amber);
}

.about-stat:nth-child(3) .about-stat__num {
  color: var(--paper);
}

.about-stat:nth-child(4) .about-stat__num {
  color: var(--red);
}

.about-stat__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
  letter-spacing: 0.04em;
}

.about-reach__note {
  margin: 20px 0 0;
  max-width: 44rem;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--mist);
}

/* ---------- 收束 ---------- */

.about-closing {
  background: var(--red);
  color: var(--paper);
}

.about-closing__eyebrow {
  color: var(--ink);
}

.about-closing__inner {
  max-width: 54rem;
}

.about-closing h2 {
  font-size: clamp(26px, 4.6vw, 50px);
  font-weight: 900;
  margin-top: 10px;
}

.about-closing__text {
  margin: 18px 0 0;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(255, 255, 255, 0.92);
}

.about-closing__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.about-closing .btn--ghost {
  border-color: var(--paper);
  color: var(--paper);
}

.about-closing .btn--ghost:hover,
.about-closing .btn--ghost:focus-visible {
  background: var(--paper);
  color: var(--red-deep);
}

.about-closing .btn--primary {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--paper);
}

.about-closing .btn--primary:hover,
.about-closing .btn--primary:focus-visible {
  background: var(--ink-2);
  border-color: var(--mint);
}

/* ---------- 响应式 ---------- */

@media (min-width: 700px) {
  .stat-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (min-width: 760px) {
  .tl__item {
    grid-template-columns: clamp(120px, 15vw, 190px) minmax(0, 1fr);
    gap: clamp(18px, 3vw, 44px);
    align-items: start;
  }
}

@media (min-width: 900px) {
  .about-hero__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.6fr);
  }

  .about-method__grid {
    grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
  }

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

@media (min-width: 1000px) {
  .stat-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}