.page-about {
  --about-gap: clamp(18px, 3vw, 34px);
  --about-pad: clamp(40px, 7vw, 92px);
  --about-rule: 1px solid var(--steel);
  color: var(--bone);
  padding-bottom: clamp(40px, 6vw, 80px);
}

.page-about .breadcrumb {
  padding-top: clamp(18px, 3vw, 32px);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-sans);
  color: var(--bone);
  text-wrap: balance;
}

.page-about h2 {
  font-size: clamp(24px, 4vw, 40px);
  line-height: 1.15;
  letter-spacing: -0.015em;
  margin: 0 0 clamp(14px, 2vw, 22px);
}

.page-about h3 {
  font-size: clamp(18px, 2.4vw, 22px);
  line-height: 1.3;
  margin: 0 0 10px;
}

.page-about p {
  font-family: var(--font-sans);
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.78;
  color: var(--bone);
  margin: 0 0 16px;
  max-width: 68ch;
}

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

.page-about a {
  color: var(--jade);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 180ms ease, color 180ms ease;
}

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

.page-about a:focus-visible {
  outline: 3px solid var(--jade);
  outline-offset: 2px;
}

.page-about .eyebrow {
  margin-bottom: 14px;
}

.page-about .num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--gold);
  letter-spacing: -0.01em;
}

/* ---------- 开篇 ---------- */
.page-about .about-open {
  display: grid;
  gap: var(--about-gap);
  padding-block: clamp(20px, 3vw, 36px) var(--about-pad);
  align-items: start;
}

.page-about .about-open__text h1 {
  font-size: clamp(30px, 7vw, 58px);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -0.02em;
  margin: 0 0 clamp(16px, 2.4vw, 26px);
}

.page-about .about-open__lede {
  font-family: var(--font-serif);
  font-size: clamp(17px, 2.2vw, 23px) !important;
  line-height: 1.6 !important;
  color: var(--bone);
  padding-left: 16px;
  border-left: 3px solid var(--ember);
}

.page-about .about-open__body {
  color: var(--fog);
}

.page-about .about-open__figure {
  margin: 0;
  position: relative;
}

.page-about .about-open__figure::before {
  content: "";
  position: absolute;
  inset: -8px -8px auto auto;
  width: 42%;
  height: 46%;
  background: linear-gradient(135deg, var(--ember) 0%, rgba(255, 90, 31, 0) 78%);
  opacity: 0.35;
  z-index: 0;
  pointer-events: none;
}

.page-about .about-open__figure img {
  position: relative;
  z-index: 1;
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  border: var(--about-rule);
}

.page-about figcaption {
  font-family: var(--font-sans);
  font-size: 13px;
  line-height: 1.6;
  color: var(--fog);
  margin-top: 10px;
  padding-left: 10px;
  border-left: 2px solid var(--steel);
}

.page-about .open-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: clamp(22px, 3vw, 34px) 0 0;
}

.page-about .open-stats__item {
  background: var(--slate);
  border: var(--about-rule);
  padding: 12px 14px;
  transition: border-color 160ms ease;
}

.page-about .open-stats__item:hover {
  border-color: var(--ember);
}

.page-about .open-stats dt {
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--fog);
  margin-bottom: 6px;
}

.page-about .open-stats dd {
  margin: 0;
  font-size: 15px;
  color: var(--bone);
}

.page-about .open-stats dd .num {
  font-size: clamp(20px, 3vw, 26px);
}

/* ---------- 起点与定位 ---------- */
.page-about .about-origin {
  background: var(--slate);
  border-top: var(--about-rule);
  border-bottom: var(--about-rule);
  padding-block: var(--about-pad);
  clip-path: polygon(0 0, 100% 14px, 100% 100%, 0 100%);
}

.page-about .about-origin__grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}

.page-about .about-origin__main p {
  color: var(--fog);
}

.page-about .about-quote {
  background: var(--ember);
  color: var(--ink);
  padding: clamp(22px, 3.4vw, 34px);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), 0 100%);
  align-self: start;
}

.page-about .about-quote__text {
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(19px, 2.6vw, 25px) !important;
  line-height: 1.35 !important;
  color: var(--ink) !important;
  letter-spacing: -0.01em;
  margin: 0 0 14px !important;
  max-width: 22ch;
}

.page-about .about-quote__note {
  font-family: var(--font-mono);
  font-size: 12.5px !important;
  letter-spacing: 0.04em;
  color: rgba(7, 13, 24, 0.72) !important;
  line-height: 1.5 !important;
  margin: 0 !important;
}

/* ---------- 年鉴 ---------- */
.page-about .about-yearbook {
  padding-block: var(--about-pad);
}

.page-about .about-yearbook__intro {
  color: var(--fog);
  max-width: 60ch;
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .yearbook {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

.page-about .year-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: thin;
  padding-bottom: 6px;
}

.page-about .year-index__link {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 132px;
  padding: 10px 12px;
  border: var(--about-rule);
  border-left: 2px solid var(--steel);
  background: var(--slate);
  transition: border-color 160ms ease, background-color 160ms ease;
}

.page-about .year-index__link:hover,
.page-about .year-index__link:focus-visible {
  border-color: var(--ember);
  border-left-color: var(--ember);
  background: rgba(255, 90, 31, 0.08);
}

.page-about .year-index__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: 20px;
  color: var(--gold);
  line-height: 1;
}

.page-about .year-index__label {
  font-size: 12.5px;
  color: var(--fog);
  line-height: 1.4;
}

.page-about .year-stream {
  border-left: 1px solid var(--steel);
  padding-left: clamp(16px, 2.6vw, 30px);
}

.page-about .year-entry {
  padding-block: clamp(16px, 2.4vw, 26px);
  scroll-margin-top: 24px;
  position: relative;
  transition: box-shadow 200ms ease;
}

.page-about .year-entry::before {
  content: "";
  position: absolute;
  left: calc(-1 * clamp(16px, 2.6vw, 30px) - 4px);
  top: 28px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--steel);
}

.page-about .year-entry:target::before {
  background: var(--jade);
  box-shadow: 0 0 0 4px rgba(47, 211, 174, 0.18);
}

.page-about .year-entry:target {
  box-shadow: inset 2px 0 0 var(--jade);
}

.page-about .year-entry + .year-entry {
  border-top: 1px dashed var(--steel);
}

.page-about .year-entry__title {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}

.page-about .year-entry__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: clamp(17px, 2.2vw, 20px);
  color: var(--ember);
  letter-spacing: 0.02em;
}

.page-about .year-entry p {
  color: var(--fog);
}

/* ---------- 媒体块 ---------- */
.page-about .about-media {
  margin: clamp(20px, 3vw, 32px) 0;
}

.page-about .about-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border: var(--about-rule);
}

.page-about .about-media--wide img {
  aspect-ratio: 16 / 7;
}

.page-about .about-media--square img {
  aspect-ratio: 3 / 2;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  background: var(--deep);
  padding-block: var(--about-pad);
  border-top: var(--about-rule);
}

.page-about .about-team__grid {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
}

.page-about .about-team__main p {
  color: var(--fog);
}

.page-about .about-team__side {
  display: grid;
  gap: clamp(18px, 3vw, 26px);
}

.page-about .gate-list {
  list-style: none;
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .gate-list__item {
  background: var(--slate);
  border: var(--about-rule);
  border-left: 3px solid var(--ember);
  padding: 16px 18px;
  transition: border-color 160ms ease, transform 160ms ease;
}

.page-about .gate-list__item:hover {
  border-left-color: var(--gold);
}

.page-about .gate-list__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--gold);
  display: block;
  margin-bottom: 6px;
}

.page-about .gate-list__item h3 {
  font-size: 17px;
  margin-bottom: 6px;
}

.page-about .gate-list__item p {
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--fog);
  margin: 0;
}

.page-about .rings {
  width: min(320px, 100%);
  aspect-ratio: 1 / 1;
  margin-inline: auto;
  display: grid;
  place-items: center;
}

.page-about .rings__outer {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  border: 1px solid var(--steel);
  background: radial-gradient(circle at 50% 30%, rgba(47, 211, 174, 0.1), rgba(7, 13, 24, 0) 62%);
  display: grid;
  place-items: center;
  position: relative;
}

.page-about .rings__mid {
  width: 76%;
  height: 76%;
  border-radius: 50%;
  border: 1px solid var(--steel);
  background: rgba(16, 27, 44, 0.86);
  display: grid;
  place-items: center;
  position: relative;
}

.page-about .rings__core {
  width: 62%;
  height: 62%;
  border-radius: 50%;
  background: var(--ember);
  color: var(--ink);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
}

.page-about .rings__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: clamp(26px, 5vw, 34px);
  line-height: 1;
  color: var(--ink);
}

.page-about .rings__label {
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: rgba(7, 13, 24, 0.78);
}

.page-about .rings__mark {
  position: absolute;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  padding: 3px 8px;
  background: var(--ink);
  border: 1px solid var(--steel);
  color: var(--bone);
  white-space: nowrap;
}

.page-about .rings__mark--outer {
  top: -10px;
  left: 50%;
  transform: translateX(-50%);
}

.page-about .rings__mark--mid {
  top: -10px;
  left: 50%;
  transform: translateX(-50%);
  color: var(--jade);
}

.page-about .rings-legend {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .rings-legend li {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--fog);
}

.page-about .rings-legend__dot {
  width: 9px;
  height: 9px;
  margin-top: 6px;
  flex: 0 0 auto;
  border-radius: 50%;
}

.page-about .rings-legend__dot--a { background: var(--steel); }
.page-about .rings-legend__dot--b { background: var(--ember); }
.page-about .rings-legend__dot--c { background: var(--jade); }

/* ---------- 本地场景 ---------- */
.page-about .about-local {
  padding-block: var(--about-pad);
  border-top: var(--about-rule);
}

.page-about .about-local__intro {
  color: var(--fog);
  max-width: 62ch;
  margin-bottom: clamp(22px, 3vw, 32px);
}

.page-about .city-grid {
  list-style: none;
  margin: 0 0 clamp(24px, 4vw, 40px);
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.page-about .city {
  background: var(--slate);
  border: 1px solid var(--steel);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: border-color 160ms ease, background-color 160ms ease;
}

.page-about .city:hover,
.page-about .city:focus-within {
  border-color: var(--ember);
  background: rgba(255, 90, 31, 0.07);
}

.page-about .city__name {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 15.5px;
  color: var(--bone);
}

.page-about .city__count {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--jade);
}

.page-about .about-local__grid {
  display: grid;
  gap: clamp(20px, 3vw, 32px);
}

.page-about .about-local__body p {
  color: var(--fog);
}

.page-about .about-local__note {
  background: var(--slate);
  border-left: 3px solid var(--gold);
  padding: clamp(18px, 2.6vw, 26px);
}

.page-about .about-local__note-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: clamp(38px, 7vw, 56px);
  line-height: 1;
  color: var(--gold);
  margin: 0 0 10px !important;
}

.page-about .about-local__note-text {
  font-size: 14px !important;
  line-height: 1.7 !important;
  color: var(--fog) !important;
  margin: 0 !important;
}

/* ---------- 合作生态 ---------- */
.page-about .about-partner {
  background: var(--slate);
  border-top: var(--about-rule);
  border-bottom: var(--about-rule);
  padding-block: var(--about-pad);
  clip-path: polygon(0 14px, 100% 0, 100% 100%, 0 100%);
}

.page-about .about-partner__grid {
  display: grid;
  gap: clamp(22px, 3.4vw, 40px);
}

.page-about .about-partner__main p {
  color: var(--fog);
}

.page-about .partner-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
  align-content: start;
}

.page-about .partner-list__item {
  background: var(--ink);
  border: 1px solid var(--steel);
  padding: 14px 16px;
  display: grid;
  gap: 6px;
  transition: border-color 160ms ease;
}

.page-about .partner-list__item:hover {
  border-color: var(--jade);
}

.page-about .partner-list__kind {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 15px;
  color: var(--gold);
}

.page-about .partner-list__desc {
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--fog);
}

/* ---------- 承诺 ---------- */
.page-about .about-promise {
  padding-block: var(--about-pad) 0;
}

.page-about .about-promise__intro {
  color: var(--fog);
  max-width: 58ch;
  margin-bottom: clamp(22px, 3vw, 32px);
}

.page-about .promise-list {
  display: grid;
  gap: 12px;
}

.page-about .promise {
  background: var(--slate);
  border: 1px solid var(--steel);
  border-left: 3px solid var(--ember);
  transition: border-color 160ms ease;
}

.page-about .promise:hover {
  border-color: var(--ember);
}

.page-about .promise__head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .promise__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 13px;
  color: var(--gold);
  letter-spacing: 0.08em;
  flex: 0 0 auto;
}

.page-about .promise__title {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: clamp(15px, 1.9vw, 17px);
  color: var(--bone);
  flex: 1 1 auto;
}

.page-about .promise__sign {
  position: relative;
  width: 14px;
  height: 14px;
  flex: 0 0 auto;
}

.page-about .promise__sign::before,
.page-about .promise__sign::after {
  content: "";
  position: absolute;
  background: var(--jade);
  transition: transform 180ms ease, background-color 180ms ease;
}

.page-about .promise__sign::before {
  left: 0;
  top: 6px;
  width: 14px;
  height: 2px;
}

.page-about .promise__sign::after {
  left: 6px;
  top: 0;
  width: 2px;
  height: 14px;
}

.page-about .promise[open] .promise__sign::after {
  transform: scaleY(0);
}

.page-about .promise__body {
  padding: 0 16px 18px;
  border-top: 1px dashed var(--steel);
  padding-top: 14px;
}

.page-about .promise__body p {
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--fog);
  margin-bottom: 10px;
}

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

.page-about .about-cta {
  margin-top: clamp(28px, 4vw, 44px);
  padding: clamp(22px, 3.4vw, 34px);
  background: linear-gradient(115deg, rgba(255, 90, 31, 0.16) 0%, rgba(16, 27, 44, 0.9) 58%);
  border: 1px solid var(--steel);
  display: grid;
  gap: 16px;
  align-items: center;
}

.page-about .about-cta__text {
  font-family: var(--font-serif);
  font-size: clamp(16px, 2.2vw, 20px) !important;
  line-height: 1.6 !important;
  color: var(--bone) !important;
  margin: 0 !important;
  max-width: 46ch;
}

.page-about .about-cta .btn {
  justify-self: start;
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .open-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .city-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
  }

  .page-about .about-cta .btn {
    justify-self: end;
  }
}

@media (min-width: 900px) {
  .page-about .about-open {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .about-open__text h1 {
    transform: skewX(-3deg);
    transform-origin: left bottom;
  }

  .page-about .about-origin__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }

  .page-about .yearbook {
    grid-template-columns: 196px minmax(0, 1fr);
    gap: clamp(32px, 5vw, 72px);
    align-items: start;
  }

  .page-about .year-index {
    position: sticky;
    top: 28px;
  }

  .page-about .year-index__list {
    flex-direction: column;
    overflow: visible;
  }

  .page-about .year-index__link {
    min-width: 0;
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }

  .page-about .about-local__grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    align-items: start;
  }

  .page-about .about-partner__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }
}

@media (min-width: 1200px) {
  .page-about .about-open {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
  }

  .page-about .city-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 1ms !important;
    animation-duration: 1ms !important;
    transform: none !important;
  }

  .page-about .about-open__text h1 {
    transform: none !important;
  }
}