/* ===== 品牌主张 · page-about ===== */
.page-about {
  --about-rail-w: clamp(248px, 29%, 356px);
  --about-gap: clamp(26px, 3.8vw, 64px);
  --about-teal-hi: #123A33;
  --about-indigo-hi: #0D1E35;
  position: relative;
  isolation: isolate;
  background: var(--ink);
  color: var(--haze);
}

.page-about::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    115deg,
    rgba(43, 242, 210, 0.05) 0 1px,
    transparent 1px 48px
  );
}

.page-about .page-shell {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: clamp(18px, 3vw, 30px);
  font-size: var(--step-13);
  letter-spacing: 0.08em;
  color: var(--slate);
}

.page-about .about-crumbs__sep {
  color: var(--line-strong);
}

.page-about .about-crumbs__current {
  color: var(--mint);
}

/* ---------- 封面 ---------- */
.page-about .about-cover {
  padding: clamp(36px, 6.4vw, 92px) 0 clamp(28px, 4.4vw, 56px);
  border-bottom: 1px solid var(--line);
}

.page-about .about-cover__title {
  margin: 16px 0 0;
  color: var(--haze);
  text-shadow: 0 0 46px rgba(43, 242, 210, 0.22);
}

.page-about .about-cover__lede {
  margin: 24px 0 0;
  max-width: 46ch;
  font-size: var(--step-20);
  line-height: 1.72;
  color: rgba(234, 242, 240, 0.84);
}

.page-about .about-cover__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: clamp(22px, 3vw, 32px);
}

/* ---------- 分屏骨架 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  padding-block: clamp(34px, 5vw, 76px) clamp(48px, 7vw, 104px);
}

.page-about .about-body {
  display: flex;
  flex-direction: column;
  gap: clamp(44px, 6.4vw, 92px);
  min-width: 0;
}

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

/* ---------- 章节标题 ---------- */
.page-about .about-section {
  scroll-margin-top: 96px;
  min-width: 0;
}

.page-about .about-section__head {
  padding-top: 20px;
  border-top: 1px solid var(--line);
  margin-bottom: clamp(22px, 3vw, 38px);
}

.page-about .about-h2 {
  margin: 12px 0 0;
  color: var(--haze);
}

.page-about .about-section__lede {
  margin: 16px 0 0;
  max-width: 52ch;
  font-size: var(--step-16);
  line-height: 1.75;
  color: var(--slate);
}

.page-about .prose p {
  max-width: 40ch;
}

.page-about .prose p + p {
  margin-top: 16px;
}

/* ---------- 旁注 ---------- */
.page-about .about-note {
  margin-top: clamp(16px, 2.2vw, 26px);
  max-width: 48ch;
  padding-left: 14px;
  border-left: 2px solid var(--line-strong);
  font-size: var(--step-13);
  line-height: 1.75;
  letter-spacing: 0.04em;
  color: var(--slate);
}

/* ---------- 图片容器 ---------- */
.page-about .about-shot {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background:
    radial-gradient(120% 90% at 18% 0%, rgba(43, 242, 210, 0.16), transparent 62%),
    var(--teal);
}

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

.page-about .about-shot::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 46px;
  height: 3px;
  background: var(--cyan);
}

.page-about .about-shot--band {
  margin-bottom: clamp(24px, 3.4vw, 44px);
}

.page-about .about-caption {
  margin-top: 12px;
  font-size: var(--step-13);
  line-height: 1.7;
  letter-spacing: 0.04em;
  color: var(--slate);
}

/* ---------- 开篇故事 ---------- */
.page-about .about-story {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

.page-about .about-story__text {
  color: rgba(234, 242, 240, 0.84);
  font-size: var(--step-16);
  line-height: 1.78;
}

@media (min-width: 760px) {
  .page-about .about-story {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: end;
  }
}

/* ---------- 三件事 ---------- */
.page-about .about-promises {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.page-about .about-promise {
  border: 1px solid var(--line-strong);
  border-left: 3px solid var(--cyan);
  border-radius: var(--radius);
  background: var(--teal);
  box-shadow: 0 3px 0 rgba(0, 0, 0, 0.35);
  overflow: hidden;
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-promise > summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 14px;
  min-height: 56px;
  padding: 14px 18px;
  list-style: none;
  cursor: pointer;
  transition: background var(--dur) var(--ease);
}

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

.page-about .about-promise > summary:hover {
  background: var(--about-teal-hi);
}

.page-about .about-promise > summary:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: -3px;
}

.page-about .about-promise__no {
  color: var(--gold);
  font-size: 1.05rem;
  line-height: 1;
}

.page-about .about-promise__title {
  font-size: clamp(1rem, 1.6vw, 1.16rem);
  font-weight: 600;
  line-height: 1.5;
  color: var(--haze);
}

.page-about .about-promise__cue {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--slate);
  transition: color var(--dur) var(--ease);
}

.page-about .about-promise[open] {
  border-color: var(--cyan);
}

.page-about .about-promise[open] .about-promise__cue {
  color: var(--cyan);
}

.page-about .about-promise__body {
  padding: 4px 18px 22px;
  border-top: 1px solid var(--line-soft);
  font-size: var(--step-16);
  line-height: 1.78;
  color: rgba(234, 242, 240, 0.84);
}

.page-about .about-promise__scene {
  margin: 14px 0 8px;
  font-size: var(--step-13);
  letter-spacing: 0.05em;
  color: var(--gold);
  line-height: 1.7;
}

@media (min-width: 760px) {
  .page-about .about-promise:nth-child(2) {
    margin-left: 24px;
  }
  .page-about .about-promise:nth-child(3) {
    margin-left: 48px;
  }
}

/* ---------- 团队 ---------- */
.page-about .about-team__figure {
  margin: 0 0 clamp(26px, 3.6vw, 46px);
}

.page-about .about-team__grid {
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  align-items: center;
}

@media (min-width: 760px) {
  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 218px) minmax(0, 1fr);
  }
}

.page-about .about-ring {
  position: relative;
  width: 100%;
  max-width: 218px;
  margin-inline: auto;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background:
    radial-gradient(circle at center, var(--ink) 0 56%, transparent 57%),
    conic-gradient(
      from -90deg,
      var(--cyan) 0 23%,
      var(--ink) 23% 26%,
      var(--gold) 26% 48%,
      var(--ink) 48% 51%,
      var(--magenta) 51% 73%,
      var(--ink) 73% 76%,
      var(--mint) 76% 98%,
      var(--ink) 98% 100%
    );
}

.page-about .about-ring__label {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  text-align: center;
}

.page-about .about-ring__num {
  color: var(--gold);
  font-size: clamp(2rem, 5vw, 2.75rem);
  line-height: 1;
}

.page-about .about-ring__unit {
  font-size: var(--step-13);
  letter-spacing: 0.1em;
  color: var(--slate);
}

.page-about .about-team__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-team__item {
  padding: 14px 16px 16px 20px;
  background: var(--teal);
  border-left: 3px solid var(--cyan);
  border-radius: var(--radius);
  transition: transform var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-team__item--a { border-left-color: var(--cyan); }
.page-about .about-team__item--b { border-left-color: var(--gold); }
.page-about .about-team__item--c { border-left-color: var(--magenta); }
.page-about .about-team__item--d { border-left-color: var(--mint); }

.page-about .about-team__item:hover,
.page-about .about-team__item:focus-within {
  transform: translateX(6px);
  background: var(--about-teal-hi);
}

.page-about .about-team__name {
  margin: 0 0 6px;
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--haze);
}

.page-about .about-team__desc {
  margin: 0;
  font-size: var(--step-16);
  line-height: 1.72;
  color: rgba(234, 242, 240, 0.78);
}

/* ---------- 时间线 ---------- */
.page-about .about-track {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-track__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(14px, 2.4vw, 30px);
  padding: clamp(20px, 2.8vw, 30px) 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: 96px;
}

.page-about .about-track__item:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .about-track__num {
  position: relative;
  min-width: 2.4ch;
  padding-top: 22px;
  font-size: clamp(1.5rem, 3.2vw, 2.2rem);
  line-height: 1;
  color: var(--gold);
}

.page-about .about-track__num::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 14px rgba(246, 196, 83, 0.7);
}

.page-about .about-track__title {
  margin: 0 0 8px;
  font-size: clamp(1.05rem, 1.9vw, 1.3rem);
  font-weight: 700;
  line-height: 1.5;
  color: var(--haze);
}

.page-about .about-track__body {
  margin: 0;
  max-width: 48ch;
  font-size: var(--step-16);
  line-height: 1.78;
  color: rgba(234, 242, 240, 0.8);
}

/* ---------- 数据来源 ---------- */
.page-about .about-source {
  display: grid;
  gap: clamp(18px, 2.6vw, 28px);
}

@media (min-width: 880px) {
  .page-about .about-source {
    grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.15fr);
    align-items: start;
  }
}

.page-about .about-source__card {
  padding: clamp(20px, 2.6vw, 30px);
  border-top: 2px solid var(--cyan);
}

.page-about .about-source__card .heading-3 {
  margin: 0 0 16px;
  color: var(--haze);
}

.page-about .about-source__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-source__list li {
  position: relative;
  padding-left: 20px;
  font-size: var(--step-16);
  line-height: 1.76;
  color: rgba(234, 242, 240, 0.82);
}

.page-about .about-source__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 9px;
  height: 1px;
  background: var(--cyan);
}

.page-about .about-source__foot {
  margin: 20px 0 0;
  padding-top: 16px;
  border-top: 1px solid var(--line-soft);
  font-size: var(--step-13);
  line-height: 1.75;
  color: var(--slate);
}

.page-about .about-cadence {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-cadence__cell {
  padding: 16px 16px 18px;
  background: var(--indigo);
  border-left: 2px solid transparent;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-cadence__cell:hover {
  border-left-color: var(--cyan);
  background: var(--about-indigo-hi);
}

.page-about .about-cadence__label {
  margin: 0 0 6px;
  font-size: var(--step-13);
  letter-spacing: 0.08em;
  color: var(--slate);
}

.page-about .about-cadence__value {
  margin: 0;
  font-size: 1.3rem;
  line-height: 1.2;
  color: var(--gold);
}

.page-about .about-cadence__note {
  margin: 8px 0 0;
  font-size: var(--step-13);
  line-height: 1.68;
  color: rgba(234, 242, 240, 0.72);
}

@media (min-width: 620px) {
  .page-about .about-cadence {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1140px) {
  .page-about .about-cadence {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 合作 ---------- */
.page-about .about-partner {
  display: grid;
  gap: clamp(22px, 3.2vw, 40px);
}

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

.page-about .about-partner__col .heading-4 {
  margin: 0 0 14px;
  color: var(--haze);
}

.page-about .about-partner__col p {
  margin: 0 0 10px;
  font-size: var(--step-16);
  line-height: 1.78;
  color: rgba(234, 242, 240, 0.82);
}

.page-about .about-partner__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-partner__list li {
  position: relative;
  padding-left: 20px;
  font-size: var(--step-16);
  line-height: 1.76;
  color: rgba(234, 242, 240, 0.82);
}

.page-about .about-partner__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 9px;
  height: 1px;
  background: var(--magenta);
}

.page-about .about-partner__stat {
  margin-top: 14px !important;
  padding: 14px 16px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background: var(--teal);
  color: var(--haze) !important;
  font-size: var(--step-16);
}

.page-about .about-partner__stat .num {
  color: var(--gold);
  font-size: 1.4rem;
}

.page-about .about-partner__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 26px;
  margin: clamp(26px, 3.4vw, 40px) 0 0;
}

.page-about .about-textlink {
  display: inline-flex;
  align-items: center;
  font-size: var(--step-16);
  color: var(--cyan);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid var(--line-strong);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

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

/* ---------- 右栏索引 ---------- */
.page-about .about-rail {
  position: relative;
  min-width: 0;
  padding: clamp(18px, 2.4vw, 26px);
  background: var(--indigo);
  border: 1px solid var(--line);
  border-top: 2px solid var(--cyan);
  border-radius: var(--radius);
  box-shadow: 0 3px 0 rgba(0, 0, 0, 0.35);
}

@media (min-width: 900px) {
  .page-about .about-rail {
    position: sticky;
    top: 24px;
  }
}

.page-about .about-rail__block + .about-rail__block {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.page-about .about-rail__block .kicker {
  margin: 0 0 12px;
}

.page-about .about-index {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-index__link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 10px 9px 12px;
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: var(--step-16);
  line-height: 1.5;
  color: rgba(234, 242, 240, 0.74);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible,
.page-about .about-index__link[aria-current] {
  color: var(--cyan);
  border-left-color: var(--cyan);
  background: rgba(43, 242, 210, 0.07);
}

.page-about .about-index--iter .about-index__link {
  font-size: var(--step-16);
}

.page-about .about-index--iter .num {
  color: var(--gold);
  font-size: var(--step-13);
  letter-spacing: 0.06em;
}

.page-about .about-rail__tags {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}
</main>