.page-about {
  --about-rail: 64px;
  background: var(--ink);
  color: var(--text);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
}

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

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(22px, 4vw, 40px) 0 clamp(44px, 6vw, 84px);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(110% 75% at 100% 0%, rgba(240, 169, 59, 0.13), transparent 62%),
    linear-gradient(180deg, rgba(18, 59, 50, 0.72), transparent 72%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  grid-template-columns: 1fr;
}

.page-about .about-hero__copy {
  display: grid;
  gap: 16px;
  align-content: start;
}

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 12.5px;
  color: var(--muted);
}

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

.page-about .breadcrumb__item a {
  color: var(--text);
  text-decoration: none;
}

.page-about .breadcrumb__item a:hover {
  color: var(--amber-soft);
}

.page-about .about-hero__chip {
  margin: 0;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  align-self: start;
  padding: 6px 12px;
  border: 1px solid var(--line-amber);
  background: rgba(240, 169, 59, 0.08);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--amber-soft);
}

.page-about .about-hero__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--amber);
}

.page-about .about-hero__title {
  margin: 0;
  font-size: clamp(30px, 5.4vw, 58px);
  font-weight: 800;
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--paper);
  max-width: 20em;
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 36em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.9;
  color: var(--text);
}

.page-about .about-hero__facts {
  list-style: none;
  margin: 6px 0 0;
  padding: 14px 0 0;
  border-top: 1px solid var(--line);
  display: grid;
  gap: 10px;
}

.page-about .about-hero__facts li {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: baseline;
  font-size: 13.5px;
}

.page-about .about-hero__fk {
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: var(--muted);
  min-width: 5em;
}

.page-about .about-hero__fv {
  color: var(--paper);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 4px;
}

.page-about .about-hero__figure {
  margin: 0;
  display: grid;
  gap: 10px;
  align-content: start;
}

.page-about .about-hero__frame {
  position: relative;
  padding: clamp(10px, 1.6vw, 16px);
  border: 1px solid var(--line-amber);
  background: linear-gradient(160deg, rgba(18, 59, 50, 0.9), rgba(8, 32, 27, 0.6));
}

.page-about .about-hero__frame::before,
.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  width: 16px;
  height: 16px;
  border: 2px solid var(--amber);
}

.page-about .about-hero__frame::before {
  top: -2px;
  left: -2px;
  border-right: 0;
  border-bottom: 0;
}

.page-about .about-hero__frame::after {
  bottom: -2px;
  right: -2px;
  border-left: 0;
  border-top: 0;
}

.page-about .about-hero__frame img {
  width: 100%;
  object-fit: cover;
  filter: saturate(0.92);
}

.page-about .about-hero__figure figcaption {
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 章节基础 ---------- */
.page-about .about-band {
  position: relative;
  padding: clamp(40px, 6vw, 84px) 0;
}

.page-about .about-band + .about-band {
  border-top: 1px solid var(--line);
}

.page-about .about-band__inner {
  position: relative;
}

.page-about .about-band__head {
  display: grid;
  gap: 8px;
  max-width: 44rem;
  margin-bottom: clamp(22px, 3.6vw, 42px);
}

.page-about .about-band__num {
  margin: 0;
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--amber);
}

.page-about .about-band__num::after {
  content: "";
  width: 52px;
  height: 1px;
  background: var(--line-amber);
}

.page-about .about-band__title {
  margin: 0;
  font-size: clamp(23px, 3.6vw, 40px);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-band__note {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-rail {
  display: none;
}

/* ---------- 起源 ---------- */
.page-about .about-origin {
  display: grid;
  gap: clamp(20px, 3vw, 36px);
  grid-template-columns: 1fr;
}

.page-about .about-origin__prose p {
  margin: 0 0 1em;
  max-width: 34em;
  font-size: clamp(15px, 1.5vw, 16.5px);
  line-height: 1.9;
  color: var(--text);
}

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

.page-about .about-origin__prose strong {
  color: var(--amber-soft);
  font-weight: 700;
}

.page-about .about-card {
  position: relative;
  padding: clamp(18px, 2.8vw, 28px);
  background: var(--paper);
  color: var(--char);
  border: 1px solid rgba(20, 32, 29, 0.16);
  box-shadow: var(--shadow-paper);
}

.page-about .about-card__title {
  margin: 0 0 14px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: #8a5c10;
}

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

.page-about .about-card__list li {
  position: relative;
  padding-left: 20px;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(20, 32, 29, 0.86);
}

.page-about .about-card__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 10px;
  height: 2px;
  background: var(--amber);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(24px, 3.6vw, 40px);
}

.page-about .about-timeline__item {
  position: relative;
  display: grid;
  gap: 10px;
  padding-left: 18px;
  border-left: 1px solid var(--line);
}

.page-about .about-timeline__year {
  font-family: var(--mono);
  font-size: clamp(30px, 7vw, 42px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: rgba(240, 169, 59, 0.5);
}

.page-about .about-timeline__card {
  position: relative;
  padding: clamp(16px, 2.4vw, 24px);
  background: var(--ink-soft);
  border: 1px solid var(--line);
  border-left: 2px solid rgba(240, 169, 59, 0.55);
}

.page-about .about-timeline__kicker {
  margin: 0 0 6px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--amber);
}

.page-about .about-timeline__card h3 {
  margin: 0 0 8px;
  font-size: clamp(16px, 2vw, 19px);
  font-weight: 700;
  line-height: 1.5;
  color: var(--paper);
}

.page-about .about-timeline__card > p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--text);
}

.page-about .about-timeline__more {
  margin-top: 12px;
}

.page-about .about-timeline__more summary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 12.5px;
  color: var(--amber-soft);
  border-bottom: 1px dotted rgba(255, 210, 138, 0.45);
  padding-bottom: 2px;
  list-style: none;
}

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

.page-about .about-timeline__more summary::before {
  content: "+";
  font-family: var(--mono);
}

.page-about .about-timeline__more[open] summary::before {
  content: "–";
}

.page-about .about-timeline__more p {
  margin: 10px 0 0;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 三组分工 ---------- */
.page-about .about-groups {
  display: grid;
  gap: clamp(16px, 2.6vw, 24px);
  grid-template-columns: 1fr;
}

.page-about .about-group {
  position: relative;
  padding: clamp(18px, 2.6vw, 26px);
  background: var(--ink-soft);
  border: 1px solid var(--line);
  transition: transform 220ms var(--ease), border-color 220ms var(--ease);
}

.page-about .about-group::before,
.page-about .about-group::after {
  content: "";
  position: absolute;
  top: -9px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--ink);
}

.page-about .about-group::before {
  left: 22px;
}

.page-about .about-group::after {
  right: 22px;
}

.page-about .about-group:hover,
.page-about .about-group:focus-within {
  transform: translateY(-4px);
  border-color: var(--line-amber);
}

.page-about .about-group__tag {
  margin: 0 0 10px;
  display: inline-block;
  padding: 3px 9px;
  border: 1px solid var(--line-amber);
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--amber-soft);
}

.page-about .about-group h3 {
  margin: 0 0 10px;
  font-size: clamp(16px, 2vw, 18px);
  line-height: 1.55;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-group__num {
  margin: 0 0 12px;
  font-family: var(--mono);
  font-size: 22px;
  color: var(--amber);
  line-height: 1;
}

.page-about .about-group__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-about .about-group__list li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--text);
}

.page-about .about-group__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 6px;
  height: 6px;
  border: 1px solid var(--moss);
  transform: rotate(45deg);
}

.page-about .about-flow {
  list-style: none;
  margin: clamp(22px, 3.6vw, 36px) 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
  grid-template-columns: 1fr;
}

.page-about .about-flow__step {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 14px 16px;
  border: 1px dashed var(--line-amber);
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--text);
}

.page-about .about-flow__idx {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--amber);
  letter-spacing: 0.1em;
}

.page-about .about-collab {
  margin: clamp(22px, 3.6vw, 38px) 0 0;
  display: grid;
  gap: 10px;
}

.page-about .about-collab img {
  width: 100%;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .about-collab figcaption {
  font-size: 12.5px;
  color: var(--muted);
  line-height: 1.7;
}

/* ---------- 原则（纸面章节） ---------- */
.page-about .about-band--paper {
  background: var(--paper);
  color: var(--char);
}

.page-about .about-band--paper .about-band__title {
  color: var(--char);
}

.page-about .about-band--paper .about-band__note {
  color: rgba(20, 32, 29, 0.62);
}

.page-about .about-band--paper .about-band__num {
  color: #9a6410;
}

.page-about .about-band--paper .about-band__num::after {
  background: rgba(20, 32, 29, 0.24);
}

.page-about .about-principles {
  display: grid;
  gap: clamp(14px, 2.2vw, 20px);
  grid-template-columns: 1fr;
}

.page-about .about-rule {
  padding: clamp(18px, 2.6vw, 26px);
  background: #fdfaf3;
  border: 1px solid rgba(20, 32, 29, 0.18);
  border-top: 3px solid var(--moss);
}

.page-about .about-rule__tag {
  margin: 0 0 10px;
  display: inline-block;
  padding: 2px 8px;
  border: 1px solid rgba(240, 169, 59, 0.65);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: #8a5c10;
}

.page-about .about-rule h3 {
  margin: 0 0 10px;
  font-size: clamp(16px, 2vw, 18px);
  line-height: 1.5;
  color: var(--char);
}

.page-about .about-rule > p {
  margin: 0;
  font-size: 14px;
  line-height: 1.9;
  color: rgba(20, 32, 29, 0.84);
}

.page-about .about-mix {
  list-style: none;
  margin: 16px 0 0;
  padding: 14px 0 0;
  border-top: 1px dashed rgba(20, 32, 29, 0.2);
  display: grid;
  gap: 9px;
}

.page-about .about-mix li {
  display: grid;
  grid-template-columns: 3.6em 1fr 2.6em;
  gap: 8px;
  align-items: center;
  font-size: 12.5px;
  color: rgba(20, 32, 29, 0.78);
}

.page-about .about-mix__label {
  font-family: var(--mono);
  font-size: 11.5px;
  color: #5c6b62;
}

.page-about .about-mix__track {
  display: block;
  height: 7px;
  background: var(--paper-soft);
  border: 1px solid rgba(20, 32, 29, 0.08);
}

.page-about .about-mix__fill {
  display: block;
  height: 100%;
  background: var(--moss);
}

.page-about .about-mix li:nth-child(1) .about-mix__fill {
  width: 41%;
}

.page-about .about-mix li:nth-child(2) .about-mix__fill {
  width: 27%;
  background: var(--cool);
}

.page-about .about-mix li:nth-child(3) .about-mix__fill {
  width: 19%;
  background: var(--cool);
}

.page-about .about-mix li:nth-child(4) .about-mix__fill {
  width: 13%;
  background: rgba(20, 32, 29, 0.35);
}

.page-about .about-mix__val {
  font-family: var(--mono);
  font-size: 11.5px;
  text-align: right;
  color: rgba(20, 32, 29, 0.9);
}

.page-about .about-scenes {
  margin-top: clamp(22px, 3.4vw, 34px);
  padding: clamp(16px, 2.6vw, 24px);
  border: 1px solid rgba(20, 32, 29, 0.16);
  background: rgba(230, 222, 205, 0.55);
}

.page-about .about-scenes__title {
  margin: 0 0 12px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: #8a5c10;
}

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

.page-about .about-scenes li {
  display: flex;
  gap: 10px;
  font-size: 13.5px;
  line-height: 1.7;
  color: rgba(20, 32, 29, 0.86);
}

.page-about .about-scenes li span {
  font-family: var(--mono);
  font-size: 11.5px;
  color: #9a6410;
  flex: none;
  padding-top: 0.15em;
}

/* ---------- 数据 ---------- */
.page-about .about-band--data {
  background: linear-gradient(180deg, var(--ink-soft), var(--ink));
}

.page-about .about-data {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
  grid-template-columns: 1fr;
  align-items: center;
}

.page-about .about-ring {
  position: relative;
  width: min(240px, 68vw);
  aspect-ratio: 1 / 1;
  margin: 0 auto;
}

.page-about .about-ring svg {
  width: 100%;
  height: 100%;
  display: block;
  transform: rotate(-90deg);
}

.page-about .about-ring__track {
  fill: none;
  stroke: rgba(245, 239, 226, 0.16);
  stroke-width: 10;
}

.page-about .about-ring__value {
  fill: none;
  stroke: var(--amber);
  stroke-width: 10;
  stroke-linecap: round;
  stroke-dasharray: 334.7 339.29;
}

.page-about .about-ring__label {
  position: absolute;
  inset: 0;
  margin: 0;
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 6px;
  text-align: center;
  padding: 0 18px;
}

.page-about .about-ring__num {
  font-family: var(--mono);
  font-size: clamp(24px, 4vw, 32px);
  color: var(--paper);
  line-height: 1;
}

.page-about .about-ring__cap {
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-stats {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(10px, 2vw, 16px);
}

.page-about .about-stat {
  padding: clamp(14px, 2.2vw, 20px);
  border: 1px solid var(--line);
  background: rgba(8, 32, 27, 0.45);
}

.page-about .about-stat__text {
  margin: 0 0 8px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-stat__num {
  margin: 0;
  font-family: var(--mono);
  font-size: clamp(22px, 3.2vw, 30px);
  line-height: 1.1;
  color: var(--amber);
}

.page-about .about-stat__unit {
  font-size: 12px;
  color: var(--text);
  margin-left: 4px;
}

.page-about .about-coverage {
  margin: clamp(24px, 4vw, 40px) 0 0;
  display: grid;
  gap: 10px;
}

.page-about .about-coverage img {
  width: 100%;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .about-coverage figcaption {
  font-size: 12.5px;
  color: var(--muted);
  line-height: 1.7;
}

/* ---------- 收束 ---------- */
.page-about .about-cta {
  padding: clamp(38px, 6vw, 76px) 0;
  border-top: 1px solid var(--line-amber);
  background: linear-gradient(120deg, var(--ink-deep), var(--ink-soft));
}

.page-about .about-cta__inner {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  grid-template-columns: 1fr;
  align-items: center;
}

.page-about .about-cta__eyebrow {
  margin: 0 0 8px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.2em;
  color: var(--amber);
}

.page-about .about-cta__title {
  margin: 0 0 10px;
  font-size: clamp(22px, 3.4vw, 34px);
  line-height: 1.3;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 40em;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--text);
}

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

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

  .page-about .about-scenes ul {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }

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

@media (min-width: 860px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: start;
    gap: clamp(28px, 3.4vw, 52px);
  }

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

  .page-about .about-group:nth-child(2) {
    margin-top: 28px;
  }

  .page-about .about-group:nth-child(3) {
    margin-top: 12px;
  }
}

@media (min-width: 900px) {
  .page-about .about-origin {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    align-items: start;
  }

  .page-about .about-data {
    grid-template-columns: minmax(0, 0.86fr) minmax(0, 1.14fr);
  }

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

  .page-about .about-timeline__item {
    grid-template-columns: minmax(120px, 200px) minmax(0, 1fr);
    gap: clamp(18px, 3vw, 40px);
    padding-left: 0;
    border-left: 0;
  }

  .page-about .about-timeline__year {
    font-size: clamp(54px, 7.4vw, 100px);
    color: rgba(240, 169, 59, 0.24);
    text-align: right;
    position: relative;
    top: -0.06em;
  }

  .page-about .about-timeline__card {
    box-shadow: var(--shadow-paper);
  }

  .page-about .about-timeline__item:nth-child(even) .about-timeline__card {
    margin-left: clamp(0px, 3vw, 40px);
  }

  .page-about .about-timeline__item:nth-child(3n) .about-timeline__card {
    margin-left: clamp(0px, 1.6vw, 20px);
  }
}

@media (min-width: 1280px) {
  .page-about .about-rail {
    display: block;
    position: absolute;
    left: -44px;
    top: 6px;
    bottom: 6px;
    width: 10px;
    border-left: 1px solid var(--line);
    background: repeating-linear-gradient(180deg, rgba(240, 169, 59, 0.5) 0 1px, transparent 1px 13px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-group,
  .page-about .about-timeline__card {
    transition: none;
  }

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