.page-about {
  --about-rule: rgba(217, 255, 247, 0.14);
  --about-paper-rule: rgba(18, 27, 24, 0.12);
  background: var(--ink);
  color: var(--mist);
  font-family: var(--font-body);
  overflow-x: clip;
}

.page-about p {
  margin: 0 0 1em;
  line-height: 1.85;
}

.page-about a {
  text-decoration: none;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(24px, 4vw, 44px) 0 clamp(36px, 5vw, 64px);
  background:
    radial-gradient(120% 90% at 88% -10%, rgba(33, 243, 200, 0.14), transparent 62%),
    linear-gradient(180deg, #04180f 0%, var(--ink) 72%);
}

.page-about .about-hero-inner {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
  align-items: start;
}

.page-about .about-hero .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 18px;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  color: var(--mist-56);
}

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

.page-about .about-hero .breadcrumb a {
  color: var(--mist);
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s var(--ease), color 0.25s var(--ease);
}

.page-about .about-hero .breadcrumb a:hover,
.page-about .about-hero .breadcrumb a:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 6.2vw, 4.3rem);
  font-weight: 700;
  line-height: 1.02;
  letter-spacing: -0.02em;
  max-width: 18ch;
}

.page-about .about-lead {
  margin-top: 1.3em;
  max-width: 58ch;
  font-size: clamp(1rem, 0.55vw + 0.9rem, 1.1rem);
  color: var(--mist-72);
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

/* 概览面板 */
.page-about .about-facts {
  background: var(--archive);
  padding: clamp(20px, 3vw, 30px);
  border-top: 2px solid var(--cyan);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.page-about .facts-title {
  margin: 0 0 6px;
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-facts dl {
  margin: 0;
}

.page-about .fact-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  padding: 12px 0;
  border-bottom: 1px dashed var(--about-rule);
}

.page-about .fact-row:last-child {
  border-bottom: 0;
}

.page-about .fact-row dt {
  font-size: 0.88rem;
  color: var(--mist-56);
}

.page-about .fact-row dd {
  margin: 0;
  font-size: 1rem;
  color: var(--cyan);
  letter-spacing: 0.02em;
}

/* 章节跳转 */
.page-about .about-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: clamp(28px, 4vw, 48px);
  padding-top: 20px;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-jump a {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  padding: 7px 13px;
  color: var(--mist-72);
  border: 1px solid var(--about-rule);
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease), background 0.25s var(--ease);
}

.page-about .about-jump a:hover,
.page-about .about-jump a:focus-visible {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  position: relative;
  padding: clamp(52px, 8vw, 108px) 0;
}

.page-about .about-sec--ink {
  background: var(--ink);
  color: var(--mist);
}

.page-about .about-sec--archive {
  background: var(--archive);
  color: var(--mist);
}

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

.page-about .about-sec--next {
  background: linear-gradient(150deg, var(--pitch) 0%, var(--ink) 68%);
  color: var(--mist);
}

.page-about .about-sec-inner {
  display: grid;
  gap: clamp(24px, 4vw, 56px);
}

.page-about .sec-ghost {
  display: block;
  font-size: clamp(2.6rem, 7vw, 4.6rem);
  line-height: 0.9;
  letter-spacing: -0.04em;
  color: rgba(33, 243, 200, 0.2);
}

.page-about .about-sec--paper .sec-ghost {
  color: rgba(15, 90, 69, 0.16);
}

.page-about .sec-kicker {
  margin: 10px 0 0;
  font-size: 0.74rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-sec--paper .sec-kicker {
  color: var(--pitch);
}

.page-about .about-sec-head h2 {
  margin: 0.45em 0 0;
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 3.6vw, 2.85rem);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.015em;
  max-width: 20ch;
}

.page-about .sec-intro {
  margin-top: 1.2em;
  max-width: 62ch;
  font-size: 0.98rem;
  color: var(--mist-72);
}

.page-about .about-sec--paper .sec-intro {
  color: #33443D;
}

.page-about .about-sec-body > p {
  max-width: 62ch;
}

.page-about .about-sec--paper .about-sec-body > p {
  color: #26332E;
}

/* 媒体框 */
.page-about .about-media {
  margin: 30px 0 0;
  position: relative;
  border: 1px solid var(--about-rule);
  background: rgba(6, 35, 28, 0.55);
}

.page-about .about-sec--paper .about-media {
  border-color: var(--about-paper-rule);
  background: #E7EFE9;
}

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

.page-about .media-caption {
  display: block;
  padding: 10px 14px;
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--mist-56);
  border-top: 1px dashed var(--about-rule);
}

.page-about .about-sec--paper .media-caption {
  color: var(--slate);
  border-top-color: var(--about-paper-rule);
}

/* ---------- 方法清单 ---------- */
.page-about .craft-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--about-paper-rule);
}

.page-about .craft-item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 6px 18px;
  padding: 24px 0;
  border-bottom: 1px solid var(--about-paper-rule);
}

.page-about .craft-idx {
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  color: var(--pitch);
  padding-top: 0.42em;
}

.page-about .craft-item h3 {
  margin: 0 0 0.5em;
  font-size: 1.06rem;
  font-weight: 700;
  color: var(--graphite);
}

.page-about .craft-item p {
  margin: 0;
  max-width: 64ch;
  font-size: 0.94rem;
  color: #34423C;
}

/* ---------- 版本时间线 ---------- */
.page-about .version-rail {
  height: 10px;
  background-image: repeating-linear-gradient(
    90deg,
    var(--cyan) 0 2px,
    transparent 2px 16px
  );
  opacity: 0.5;
  border-top: 1px solid var(--about-rule);
  margin: 8px 0 18px;
}

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

.page-about .version-item {
  position: relative;
  padding: 20px 18px 18px;
  background: var(--archive);
  border: 1px solid var(--about-rule);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
  transition: border-color 0.28s var(--ease), background 0.28s var(--ease);
}

.page-about .version-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 34px;
  height: 3px;
  background: var(--cyan);
}

.page-about .version-item:hover,
.page-about .version-item:focus-visible {
  border-color: var(--cyan-line);
  background: #0d4534;
  outline: none;
}

.page-about .version-tag {
  display: inline-block;
  font-size: 0.76rem;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .version-item h3 {
  margin: 0.55em 0 0.4em;
  font-size: 1.06rem;
  font-weight: 700;
  color: var(--mist);
}

.page-about .version-sum {
  margin: 0;
  font-size: 0.9rem;
  color: var(--mist-72);
}

.page-about .version-more {
  margin: 10px 0 0;
  font-size: 0.88rem;
  color: rgba(217, 255, 247, 0.6);
  overflow: hidden;
  max-height: 12em;
  transition: max-height 0.36s var(--ease), opacity 0.3s var(--ease), margin 0.3s var(--ease);
}

/* ---------- 团队折叠 ---------- */
.page-about .team-folds {
  display: grid;
  gap: 10px;
  margin-bottom: 28px;
}

.page-about .team-fold {
  border: 1px solid var(--about-rule);
  background: rgba(6, 35, 28, 0.4);
  transition: border-color 0.25s var(--ease);
}

.page-about .team-fold[open],
.page-about .team-fold:hover {
  border-color: var(--cyan-line);
}

.page-about .team-fold summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto;
  gap: 14px;
  align-items: center;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .team-fold summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1.1rem;
  line-height: 1;
  color: var(--cyan);
}

.page-about .team-fold[open] summary::after {
  content: "−";
}

.page-about .team-idx {
  font-size: 0.76rem;
  letter-spacing: 0.1em;
  color: var(--slate);
}

.page-about .team-role {
  font-size: 1rem;
  font-weight: 500;
  color: var(--mist);
}

.page-about .team-count {
  font-size: 0.82rem;
  color: var(--cyan);
}

.page-about .team-body {
  padding: 0 18px 18px;
  border-top: 1px dashed var(--about-rule);
  padding-top: 14px;
}

.page-about .team-body p {
  margin: 0;
  max-width: 62ch;
  font-size: 0.92rem;
  color: var(--mist-72);
}

/* ---------- 合作生态 ---------- */
.page-about .partner-board {
  display: grid;
  gap: 14px;
}

.page-about .partner-card {
  padding: 22px 20px;
  background: #ffffff;
  border: 1px solid var(--about-paper-rule);
  border-left: 4px solid var(--amber);
  transition: transform 0.28s var(--ease), border-color 0.28s var(--ease);
}

.page-about .partner-card:hover {
  transform: translateY(-3px);
  border-color: var(--pitch);
  border-left-color: var(--flare);
}

.page-about .partner-card h3 {
  margin: 12px 0 0.5em;
  font-size: 1.04rem;
  font-weight: 700;
  color: var(--graphite);
}

.page-about .partner-card p {
  margin: 0;
  font-size: 0.92rem;
  color: #35433D;
}

.page-about .partner-card--honor {
  border-left-color: var(--pitch);
  background: #EEF5F0;
}

.page-about .partner-card .tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
}

/* ---------- 收束 ---------- */
.page-about .next-grid {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
}

.page-about .next-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-content: start;
}

.page-about .next-contact {
  padding: 22px 20px;
  background: rgba(6, 35, 28, 0.55);
  border: 1px solid var(--about-rule);
  border-top: 2px solid var(--amber);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%);
}

.page-about .contact-title {
  margin: 0 0 14px;
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--amber);
}

.page-about .contact-line {
  display: grid;
  gap: 2px;
  margin: 0 0 12px;
  font-size: 0.9rem;
}

.page-about .contact-line span {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--slate);
}

.page-about .contact-line strong {
  font-weight: 500;
  color: var(--mist);
  word-break: break-word;
}

.page-about .contact-note {
  margin: 4px 0 0;
  font-size: 0.78rem;
  line-height: 1.7;
  color: var(--mist-56);
}

/* ---------- 断点 ---------- */
@media (min-width: 760px) {
  .page-about .partner-board {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .version-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (min-width: 960px) {
  .page-about .about-hero-inner {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  }

  .page-about .about-sec-inner {
    grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.5fr);
    align-items: start;
  }

  .page-about .about-sec-inner--stack {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .about-sec-inner--stack .about-sec-head h2 {
    max-width: 26ch;
  }

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

  /* 版本说明在宽屏随悬停/聚焦展开 */
  .page-about .version-more {
    max-height: 0;
    opacity: 0;
    margin-top: 0;
  }

  .page-about .version-item:hover .version-more,
  .page-about .version-item:focus-visible .version-more,
  .page-about .version-item:focus-within .version-more {
    max-height: 12em;
    opacity: 1;
    margin-top: 10px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-sec-head h2 {
    max-width: 16ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .version-more,
  .page-about .version-item,
  .page-about .partner-card,
  .page-about .about-jump a {
    transition: none;
  }
}