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

/* ---------- 页头 ---------- */
.page-about .about-top {
  padding-top: clamp(24px, 4.5vw, 52px);
  padding-bottom: clamp(30px, 5vw, 58px);
}

.page-about .about-head {
  margin-top: clamp(20px, 3.5vw, 38px);
}

.page-about .about-head .eyebrow {
  display: inline-block;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--grape-lite);
}

.page-about .about-title {
  margin: clamp(14px, 2vw, 24px) 0 0;
  max-width: 15ch;
  line-height: 1.16;
}

.page-about .about-lede {
  margin-top: clamp(16px, 2.2vw, 26px);
  max-width: 58ch;
}

.page-about .about-index-nav {
  margin-top: clamp(28px, 4vw, 48px);
}

.page-about .about-index {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  border-top: 1px solid var(--line);
}

.page-about .about-index li {
  border-bottom: 1px solid var(--line);
}

.page-about .about-index a {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 4px;
  color: var(--text);
  text-decoration: none;
  font-size: 14.5px;
  line-height: 1.6;
  transition: background-color .18s ease, padding-left .18s ease;
}

.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  background: rgba(109, 46, 143, .07);
  padding-left: 10px;
}

.page-about .about-index .mono {
  color: var(--grape);
  font-size: 12px;
  letter-spacing: .08em;
}

/* ---------- 区块骨架 ---------- */
.page-about .about-sec {
  padding: clamp(44px, 7vw, 92px) 0;
  border-top: 1px solid var(--line);
}

.page-about .about-sec-head {
  display: flex;
  align-items: flex-start;
  gap: clamp(14px, 2.2vw, 26px);
  margin-bottom: clamp(24px, 3.6vw, 42px);
}

.page-about .about-sec-no {
  flex: none;
  margin: 0;
  padding-top: 9px;
  border-top: 2px solid var(--gold);
  color: var(--gold);
  font-size: 12px;
  letter-spacing: .14em;
  line-height: 1;
}

.page-about .about-sec-head h2 {
  margin: 0;
  max-width: 20ch;
  font-family: var(--serif);
  font-size: clamp(1.45rem, 2.6vw, 2.15rem);
  font-weight: 700;
  line-height: 1.28;
  letter-spacing: .01em;
}

.page-about .about-grid {
  display: grid;
  gap: clamp(26px, 4vw, 50px);
  grid-template-columns: minmax(0, 1fr);
}

.page-about .about-body > p {
  max-width: 66ch;
  margin: 0 0 1.1em;
  line-height: 1.85;
}

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

.page-about .about-lede-line {
  padding-left: 14px;
  border-left: 3px solid var(--grape);
  font-size: 1.02rem;
}

.page-about .about-sub {
  margin: clamp(22px, 3vw, 34px) 0 14px;
  font-family: var(--serif);
  font-size: 1.08rem;
  font-weight: 700;
  letter-spacing: .01em;
}

.page-about .about-foot-note {
  margin: 0;
  max-width: 62ch;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(36, 22, 51, .7);
}

.page-about .about-note {
  border-left: 2px solid var(--grape-lite);
  padding: 2px 0 2px 16px;
  font-size: 14px;
  line-height: 1.85;
}

.page-about .about-note p {
  margin: 0 0 14px;
}

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

.page-about .about-note--ink {
  color: rgba(246, 242, 233, .84);
}

.page-about .about-note--cite {
  border-left: 0;
  padding-left: 0;
}

.page-about .about-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 14px;
  padding-bottom: 2px;
  font-size: 13.5px;
  color: var(--grape);
  text-decoration: none;
  border-bottom: 1px solid currentColor;
}

.page-about .about-more:hover,
.page-about .about-more:focus-visible {
  color: var(--grape-lite);
}

.page-about .about-more--ink {
  color: var(--green);
}

/* ---------- 01 边界列表 ---------- */
.page-about .boundary-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .boundary-list li {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 4px 12px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .boundary-code {
  grid-column: 1;
  grid-row: 1;
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--gold);
  align-self: baseline;
}

.page-about .boundary-title {
  grid-column: 2;
  grid-row: 1;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.7;
}

.page-about .boundary-text {
  grid-column: 2;
  grid-row: 2;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(36, 22, 51, .78);
}

/* ---------- 02 认证深色分区 ---------- */
.page-about .about-cert {
  position: relative;
  overflow: hidden;
  padding: clamp(52px, 8vw, 104px) 0;
  background: var(--ink);
  color: var(--paper);
  border-top: 1px solid var(--line);
}

.page-about .about-cert-media {
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

.page-about .about-cert-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .2;
}

.page-about .about-cert-media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(120% 90% at 12% 0%, rgba(30, 47, 77, .62), var(--ink) 72%);
}

.page-about .about-cert .shell {
  position: relative;
  z-index: 1;
}

.page-about .about-cert .about-sec-head h2 {
  color: var(--paper);
}

.page-about .about-cert .about-sec-no {
  border-top-color: var(--green);
  color: var(--green);
}

.page-about .about-cert .about-body > p {
  color: rgba(246, 242, 233, .86);
}

.page-about .ring-wrap {
  max-width: 340px;
  margin: 6px auto clamp(18px, 3vw, 30px);
}

.page-about .ring-map {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .ring-grid circle,
.page-about .ring-grid line {
  fill: none;
  stroke: rgba(164, 111, 196, .26);
  stroke-width: 1;
}

.page-about .ring-band {
  fill: none;
  stroke-width: 40;
  opacity: .58;
  transition: opacity .25s ease;
}

.page-about .ring-band--1 { stroke: var(--green); }
.page-about .ring-band--2 { stroke: var(--grape-lite); }
.page-about .ring-band--3 { stroke: var(--gold); }

.page-about .ring-band.is-linked {
  opacity: 1;
}

.page-about .ring-core {
  fill: var(--paper);
  font-family: var(--mono);
  font-size: 15px;
  letter-spacing: .06em;
  text-anchor: middle;
}

.page-about .ring-core-sub {
  fill: rgba(246, 242, 233, .7);
  font-size: 11.5px;
  text-anchor: middle;
}

.page-about .ring-label {
  fill: rgba(246, 242, 233, .82);
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  text-anchor: middle;
}

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

.page-about .cert-item {
  padding: 14px 16px;
  border-left: 2px solid rgba(216, 210, 196, .28);
  background: rgba(246, 242, 233, .04);
  transition: border-color .2s ease, background-color .2s ease;
}

.page-about .cert-item.is-linked {
  border-left-color: var(--gold);
  background: rgba(227, 180, 72, .1);
}

.page-about .cert-code {
  margin: 0 0 5px;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--gold);
}

.page-about .cert-desc {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(246, 242, 233, .84);
}

/* ---------- 03 编号对照 ---------- */
.page-about .spec-list {
  margin: 0 0 1.3em;
  padding: 0;
}

.page-about .spec-row {
  display: grid;
  gap: 6px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
}

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

.page-about .spec-row dt {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--grape);
}

.page-about .spec-row dd {
  margin: 0;
}

.page-about .spec-row dd strong {
  display: block;
  margin-bottom: 4px;
  font-family: var(--serif);
  font-size: 1.05rem;
  font-weight: 700;
}

.page-about .spec-row dd span {
  display: block;
  max-width: 56ch;
  font-size: 14.5px;
  line-height: 1.82;
  color: rgba(36, 22, 51, .82);
}

.page-about .quote-block {
  margin: 0;
  padding: 12px 14px;
  background: rgba(227, 180, 72, .1);
  border-left: 3px solid var(--gold);
  font-size: 14px;
  line-height: 1.82;
}

/* ---------- 04 时间线 ---------- */
.page-about .timeline-grid {
  display: grid;
  gap: clamp(28px, 4vw, 50px);
  grid-template-columns: minmax(0, 1fr);
}

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 14px;
  bottom: 14px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold), var(--grape-lite) 28%, var(--grape) 62%, var(--line));
}

.page-about .timeline-item {
  position: relative;
  padding-left: 30px;
}

.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 18px;
  width: 11px;
  height: 11px;
  background: var(--grape);
  box-shadow: 0 0 0 3px var(--paper);
  z-index: 1;
}

.page-about .timeline-summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 0;
  cursor: pointer;
  list-style: none;
  border-bottom: 1px solid var(--line);
}

.page-about .timeline-summary::-webkit-details-marker { display: none; }
.page-about .timeline-summary::marker { content: ""; }

.page-about .timeline-year {
  flex: none;
  padding: 2px 8px;
  background: var(--gold);
  color: var(--ink);
  font-size: 12.5px;
  letter-spacing: .08em;
}

.page-about .timeline-title {
  font-family: var(--serif);
  font-size: 1.06rem;
  font-weight: 700;
  line-height: 1.5;
}

.page-about .timeline-sign {
  position: relative;
  flex: none;
  align-self: center;
  width: 12px;
  height: 12px;
  margin-left: auto;
}

.page-about .timeline-sign::before,
.page-about .timeline-sign::after {
  content: "";
  position: absolute;
  background: var(--grape);
}

.page-about .timeline-sign::before {
  left: 0;
  right: 0;
  top: 5.5px;
  height: 1px;
}

.page-about .timeline-sign::after {
  top: 0;
  bottom: 0;
  left: 5.5px;
  width: 1px;
}

.page-about .timeline-item details[open] .timeline-sign::after {
  display: none;
}

.page-about .timeline-item .detail-body {
  padding: 8px 0 18px;
}

.page-about .timeline-item .detail-body p {
  margin: 0;
  max-width: 58ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: rgba(36, 22, 51, .78);
}

.page-about .timeline-aside {
  display: grid;
  gap: 22px;
  align-content: start;
}

.page-about .aspect-block,
.page-about .aside-block .eyebrow {
  display: block;
}

.page-about .aside-block .eyebrow {
  display: block;
  margin-bottom: 8px;
}

.page-about .aside-block p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(36, 22, 51, .78);
}

.page-about .about-archive-media {
  margin: 0;
}

/* ---------- 05 维护节奏 ---------- */
.page-about .cadence-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-bottom: clamp(20px, 3vw, 30px);
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .cadence {
  display: grid;
  gap: 8px;
  align-content: start;
  padding: 20px 18px;
  background: var(--paper);
}

.page-about .cadence-cycle {
  margin: 0;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--green-deep);
}

.page-about .cadence h3 {
  margin: 0;
  font-family: var(--serif);
  font-size: 1.02rem;
  font-weight: 700;
}

.page-about .cadence p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(36, 22, 51, .78);
}

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

.page-about .role-list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(36, 22, 51, .82);
}

/* ---------- 06 引用与更正 ---------- */
.page-about .cite-block {
  margin: 0 0 1.3em;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--gold);
  background: rgba(109, 46, 143, .045);
}

.page-about .cite-block .eyebrow {
  display: block;
  margin-bottom: 10px;
}

.page-about .cite-sample {
  margin: 0;
  font-size: 13px;
  line-height: 1.9;
  letter-spacing: .01em;
  color: var(--text);
  word-break: break-word;
}

.page-about .step-list {
  list-style: none;
  margin: 0 0 1.3em;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .step-list li {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 12px;
  align-items: baseline;
  padding: 13px 15px;
  background: var(--paper);
  font-size: 14.5px;
  line-height: 1.8;
}

.page-about .step-no {
  color: var(--grape);
  font-size: 12px;
  letter-spacing: .08em;
}

.page-about .about-ripe-media {
  margin: 0 0 18px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-index {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-index li {
    border-right: 1px solid var(--line);
  }

  .page-about .about-index li:nth-child(3n) {
    border-right: 0;
  }

  .page-about .spec-row {
    grid-template-columns: 148px minmax(0, 1fr);
    gap: 4px 24px;
  }

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

@media (min-width: 940px) {
  .page-about .about-grid {
    grid-template-columns: minmax(0, 1fr) 264px;
  }

  .page-about .about-grid--cite {
    grid-template-columns: minmax(0, 1fr) 250px;
  }

  .page-about .timeline-grid {
    grid-template-columns: minmax(0, 1fr) 280px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition: none !important;
    animation: none !important;
  }
}