/* ===================== 平台介绍页 ===================== */
.page-about {
  position: relative;
  isolation: isolate;
  overflow-x: clip;
  padding-bottom: clamp(56px, 7vw, 104px);
}

.page-about::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(232, 237, 240, 0.022) 0 1px,
    transparent 1px 96px
  );
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding-top: clamp(18px, 2.6vw, 30px);
}

.page-about .about-crumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--dust);
}

.page-about .about-crumbs a {
  color: var(--dust);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-crumbs a:hover,
.page-about .about-crumbs a:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

.page-about .about-crumbs li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--line);
}

.page-about .about-crumbs [aria-current="page"] {
  color: var(--mist);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 32px;
  padding-block: clamp(22px, 3.6vw, 44px) clamp(46px, 6vw, 84px);
}

.page-about .about-hero__label {
  margin: 0 0 18px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--dust);
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 5.2vw, 60px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--mist);
}

.page-about .about-hero__lead {
  margin: 22px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(232, 237, 240, 0.82);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(118px, 1fr));
  gap: 1px;
  margin: 32px 0 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  padding: 16px 18px;
  background: var(--night);
}

.page-about .about-stat dt {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--dust);
}

.page-about .about-stat dd {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.4vw, 34px);
  font-weight: 700;
  line-height: 1;
  color: var(--amber);
}

.page-about .about-stat__unit {
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 400;
  color: var(--dust);
}

.page-about .about-hero__media {
  margin: 0;
}

.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border: 1px solid var(--line);
  background: var(--graphite);
}

.page-about .about-hero__media figcaption {
  margin-top: 12px;
  padding-left: 10px;
  border-left: 2px solid var(--turf-hi);
  font-size: 12px;
  line-height: 1.7;
  color: var(--dust);
}

@media (min-width: 960px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    gap: clamp(36px, 5vw, 76px);
    align-items: center;
  }
}

/* ---------- 章节骨架 ---------- */
.page-about .about-section {
  padding-block: clamp(46px, 5.6vw, 84px);
  border-top: 1px solid var(--line);
}

.page-about .about-head {
  display: grid;
  gap: 12px;
  margin-bottom: clamp(26px, 3.6vw, 44px);
}

.page-about .about-head__label {
  margin: 0;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--dust);
}

.page-about .about-head__label .num {
  color: var(--lime);
}

.page-about .about-head__title {
  margin: 0;
  max-width: 24ch;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3.4vw, 42px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--mist);
}

.page-about .about-head__note {
  margin: 0;
  max-width: 60ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--dust);
}

/* ---------- 01 起点 ---------- */
.page-about .about-origin {
  display: grid;
  gap: 24px;
  margin-bottom: clamp(32px, 4.4vw, 54px);
}

.page-about .about-origin__body p {
  margin: 0 0 18px;
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.88;
  color: rgba(232, 237, 240, 0.84);
}

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

.page-about .about-note {
  align-self: start;
  padding: 4px 0 4px 18px;
  border-left: 2px solid var(--amber);
}

.page-about .about-note__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: rgba(232, 237, 240, 0.78);
}

.page-about .about-note__source {
  margin: 12px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--dust);
}

@media (min-width: 900px) {
  .page-about .about-origin {
    grid-template-columns: minmax(0, 1.65fr) minmax(0, 1fr);
    gap: clamp(32px, 4.6vw, 68px);
    align-items: start;
  }
}

/* 时间轴 */
.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 22px;
  border-left: 1px solid var(--line);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: 26px;
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 7px;
  width: 9px;
  height: 9px;
  background: var(--lime);
  box-shadow: 0 0 0 4px rgba(216, 243, 74, 0.12);
}

.page-about .timeline__year {
  margin: 0 0 6px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--dust);
}

.page-about .timeline__year .num {
  color: var(--amber);
  font-size: 13px;
  letter-spacing: 0;
}

.page-about .timeline__body h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.35;
  color: var(--mist);
}

.page-about .timeline__body p {
  margin: 0;
  max-width: 62ch;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--dust);
}

@media (min-width: 720px) {
  .page-about .timeline__item {
    display: grid;
    grid-template-columns: 132px minmax(0, 1fr);
    gap: 24px;
  }

  .page-about .timeline__year {
    margin: 3px 0 0;
    text-align: right;
  }
}

/* ---------- 02 数据生产 ---------- */
.page-about .checkflow {
  list-style: none;
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .checkflow__step {
  padding: 24px 22px 26px;
  background: var(--night);
  transition: background 0.3s var(--ease);
}

.page-about .checkflow__step:hover,
.page-about .checkflow__step:focus-within {
  background: var(--turf);
}

.page-about .checkflow__idx {
  display: block;
  margin-bottom: 14px;
  font-size: 28px;
  font-weight: 700;
  line-height: 1;
  color: var(--amber);
}

.page-about .checkflow__step h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .checkflow__step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--dust);
}

@media (min-width: 780px) {
  .page-about .checkflow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .about-pipeline__media {
  margin: clamp(28px, 4vw, 46px) 0 0;
}

.page-about .about-pipeline__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid var(--line);
  background: var(--graphite);
}

.page-about .about-pipeline__media figcaption {
  margin-top: 12px;
  font-size: 12px;
  line-height: 1.7;
  color: var(--dust);
}

/* ---------- 03 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: 28px;
}

.page-about .about-team__lead p {
  margin: 0 0 16px;
  max-width: 48ch;
  font-size: 16px;
  line-height: 1.88;
  color: rgba(232, 237, 240, 0.84);
}

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

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

.page-about .about-team__roles li {
  padding: 20px 22px;
  background: var(--night);
}

.page-about .about-team__roles h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  color: var(--turf-hi);
}

.page-about .about-team__roles p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--dust);
}

@media (min-width: 900px) {
  .page-about .about-team {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
    gap: clamp(32px, 4.6vw, 68px);
    align-items: start;
  }
}

/* ---------- 04 版本演进 ---------- */
.page-about .versions {
  border-top: 1px solid var(--line);
}

.page-about .versions__item {
  border-bottom: 1px solid var(--line);
  transition: background 0.3s var(--ease);
}

.page-about .versions__item[open] {
  background: rgba(18, 58, 46, 0.55);
}

.page-about .versions__item summary {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr) max-content;
  align-items: center;
  gap: 16px;
  padding: 18px 10px;
  cursor: pointer;
  list-style: none;
  transition: color 0.2s var(--ease);
}

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

.page-about .versions__item summary:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: -2px;
}

.page-about .versions__no {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  color: var(--amber);
}

.page-about .versions__name {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--mist);
}

.page-about .versions__flag {
  padding: 3px 9px;
  border: 1px solid var(--lime);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--lime);
  white-space: nowrap;
}

.page-about .versions__body {
  padding: 0 10px 22px;
}

.page-about .versions__body p {
  margin: 0;
  max-width: 68ch;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--dust);
}

@media (min-width: 720px) {
  .page-about .versions__item summary {
    padding: 20px 14px;
  }

  .page-about .versions__body {
    padding: 0 14px 24px 86px;
  }
}

/* ---------- 05 合作与认可 ---------- */
.page-about .about-eco {
  display: grid;
  gap: 28px;
}

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

.page-about .about-eco__partners li {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
  padding: 20px 22px;
  background: var(--night);
}

.page-about .about-eco__num {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--amber);
}

.page-about .about-eco__partners h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .about-eco__partners p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--dust);
}

.page-about .about-eco__awards {
  align-self: start;
  padding: 22px;
  border: 1px solid var(--line);
  border-left: 2px solid var(--turf-hi);
  background: linear-gradient(150deg, rgba(18, 58, 46, 0.65), rgba(11, 31, 42, 0.15));
}

.page-about .about-eco__awards h3 {
  margin: 0 0 18px;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--dust);
}

.page-about .about-eco__awards ul {
  list-style: none;
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
}

.page-about .about-eco__awards li {
  display: grid;
  gap: 5px;
}

.page-about .about-eco__awards .num {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--amber);
}

.page-about .about-eco__awards li span:last-child {
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--mist);
}

@media (min-width: 900px) {
  .page-about .about-eco {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.7fr);
    gap: clamp(32px, 4.6vw, 68px);
    align-items: start;
  }
}

/* ---------- 06 站点信息 ---------- */
.page-about .about-info {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin: 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-info > div {
  display: grid;
  gap: 7px;
  padding: 18px 20px;
  background: var(--night);
}

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

.page-about .about-info dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .about-info dd.num {
  color: var(--amber);
  letter-spacing: 0.02em;
}

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

.page-about .about-info__cta {
  margin: 26px 0 0;
  max-width: 72ch;
  font-size: 15px;
  line-height: 1.9;
  color: var(--dust);
}

.page-about .about-info__cta a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(216, 243, 74, 0.42);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-info__cta a:hover,
.page-about .about-info__cta a:focus-visible {
  color: var(--mist);
  border-bottom-color: var(--mist);
}