.page-about {
  --about-grid-soft: rgba(242, 230, 201, 0.04);
  --about-line-soft: rgba(242, 230, 201, 0.08);
  --about-glow-purple: rgba(177, 75, 255, 0.22);
  --about-glow-blue: rgba(41, 197, 255, 0.18);
  --about-glow-pink: rgba(255, 46, 136, 0.16);
  background: var(--bg-ink);
  color: var(--paper);
  overflow-x: hidden;
}

/* ---------- 首屏框景 ---------- */
.about-hero {
  position: relative;
  padding: 2rem 1rem 2.5rem;
  border-bottom: 1px solid var(--gray);
  background:
    linear-gradient(var(--about-grid-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-grid-soft) 1px, transparent 1px),
    var(--bg-ink);
  background-size: 26px 26px;
}

.about-hero::before,
.about-hero::after {
  content: "";
  position: absolute;
  width: 26px;
  height: 26px;
  pointer-events: none;
  z-index: 1;
}

.about-hero::before {
  top: 10px;
  left: 10px;
  border-top: 2px solid var(--purple);
  border-left: 2px solid var(--purple);
}

.about-hero::after {
  bottom: 10px;
  right: 10px;
  border-bottom: 2px solid var(--purple);
  border-right: 2px solid var(--purple);
}

.about-hero-inner {
  position: relative;
  max-width: 900px;
}

.about-hero-code {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--blue);
  margin: 1rem 0 0.75rem;
}

.about-hero-title {
  font-family: var(--font-head);
  font-size: clamp(1.9rem, 5.5vw, 3.4rem);
  font-weight: 700;
  line-height: 1.18;
  letter-spacing: -0.01em;
  margin: 0 0 1rem;
}

.about-hero-title::after {
  content: "";
  display: block;
  width: 3rem;
  height: 3px;
  margin-top: 1rem;
  background: linear-gradient(90deg, var(--purple), var(--blue), var(--pink));
}

.title-accent {
  color: var(--pink);
}

.about-hero-lead {
  max-width: 32em;
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(242, 230, 201, 0.84);
}

.about-hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  list-style: none;
  margin: 1.5rem 0 0;
  padding: 0.6rem 0;
  border-top: 1px solid var(--about-line-soft);
  border-bottom: 1px solid var(--about-line-soft);
}

.about-hero-meta li {
  display: flex;
  align-items: baseline;
  gap: 0.4rem;
}

.about-hero-meta .meta-label {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.12em;
  color: var(--gray);
}

.about-hero-meta .meta-value {
  font-family: var(--font-head);
  font-size: 1rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .scroll-progress {
  position: absolute;
  bottom: -0.75rem;
  left: 0;
  height: 2px;
  width: 0;
  background: linear-gradient(90deg, var(--purple), var(--blue), var(--pink));
  z-index: 2;
}

/* ---------- 本页索引条 ---------- */
.about-index {
  border-bottom: 1px solid var(--gray);
  background: var(--panel);
}

.about-index-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem 1.25rem;
  padding-top: 0.7rem;
  padding-bottom: 0.7rem;
}

.about-index-title {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.18em;
  color: var(--yellow);
}

.about-index-link {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  text-decoration: none;
  color: var(--paper);
  opacity: 0.68;
  transition: opacity 0.2s ease, color 0.2s ease;
}

.about-index-link:hover {
  opacity: 1;
  color: var(--blue);
}

/* ---------- 品牌缘起 ---------- */
.about-origin {
  padding: 3rem 0;
  background:
    radial-gradient(ellipse at 85% 18%, var(--about-glow-purple), transparent 42%),
    var(--bg-ink);
}

.about-origin-grid {
  display: grid;
  gap: 2.5rem;
}

.about-origin-copy .section-head {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.page-about .section-title-index {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--blue);
}

.page-about .section-title {
  margin: 0;
  font-family: var(--font-head);
  font-size: clamp(1.7rem, 4vw, 2.6rem);
  font-weight: 700;
  line-height: 1.2;
}

.origin-lead {
  max-width: 30em;
  font-size: 1.05rem;
  line-height: 1.8;
  color: rgba(242, 230, 201, 0.9);
  border-left: 2px solid var(--purple);
  padding-left: 1rem;
  margin: 0 0 1.5rem;
}

.origin-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.75rem;
}

.origin-list li {
  display: flex;
  gap: 0.9rem;
  align-items: flex-start;
  border-bottom: 1px solid var(--about-line-soft);
  padding-bottom: 0.75rem;
}

.origin-char {
  flex: 0 0 2.25rem;
  width: 2.25rem;
  height: 2.25rem;
  display: grid;
  place-items: center;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--purple);
  background: var(--panel);
  border: 1px solid var(--gray);
}

.origin-list strong {
  display: block;
  font-size: 0.95rem;
  line-height: 1.4;
}

.origin-list p {
  margin: 0.2rem 0 0;
  max-width: 30em;
  font-size: 0.85rem;
  line-height: 1.7;
  color: rgba(242, 230, 201, 0.68);
}

.origin-footnote {
  max-width: 32em;
  font-size: 0.9rem;
  line-height: 1.8;
  color: rgba(242, 230, 201, 0.72);
  margin: 1.4rem 0 0;
}

.origin-footnote a {
  color: var(--purple);
  text-decoration: none;
  border-bottom: 1px solid rgba(177, 75, 255, 0.4);
}

.origin-footnote a:hover {
  color: var(--blue);
  border-bottom-color: var(--blue);
}

.about-origin-side {
  display: grid;
  gap: 1.5rem;
}

.about-logo-figure {
  margin: 0;
}

.page-about .media-frame {
  border: 1px solid var(--gray);
  background: var(--panel);
}

.about-logo-figure img,
.about-team-figure img,
.about-credential-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.about-logo-figure .media-index {
  display: block;
  padding: 0.6rem 0.8rem;
  font-family: var(--font-mono);
  font-size: 0.64rem;
  letter-spacing: 0.2em;
  color: var(--blue);
}

/* 技能树 */
.origin-tree {
  border: 1px solid var(--gray);
  padding: 1.2rem;
  background:
    linear-gradient(var(--about-line-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-line-soft) 1px, transparent 1px),
    var(--panel);
  background-size: 18px 18px;
}

.tree-root {
  display: flex;
  align-items: center;
  font-family: var(--font-head);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--paper);
  padding-bottom: 1rem;
  margin-bottom: 1rem;
  border-bottom: 1px dashed var(--gray);
}

.tree-root::before {
  content: "◆ ";
  color: var(--purple);
}

.tree-branches {
  display: grid;
  gap: 0.7rem;
}

.tree-branch {
  display: grid;
  grid-template-columns: 4.2em 1fr;
  gap: 0.1rem 0.7rem;
  padding: 0.6rem 0.7rem;
  border: 1px solid var(--about-line-soft);
  background: rgba(11, 14, 20, 0.68);
}

.branch-head {
  grid-row: span 3;
  align-self: start;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1.1rem;
  line-height: 1.4;
}

.branch-primary .branch-head { color: var(--purple); }
.branch-blue .branch-head { color: var(--blue); }
.branch-pink .branch-head { color: var(--pink); }

.branch-node {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  line-height: 1.55;
  color: rgba(242, 230, 201, 0.74);
}

/* ---------- 发展里程碑 ---------- */
.about-milestones {
  padding: 3rem 0;
  border-top: 1px solid var(--gray);
  border-bottom: 1px solid var(--gray);
  background:
    linear-gradient(to bottom, var(--bg-ink), rgba(22, 27, 38, 0.52), var(--bg-ink)),
    var(--bg-ink);
}

.about-milestones .section-head {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.milestones-intro {
  max-width: 34em;
  line-height: 1.8;
  font-size: 0.95rem;
  color: rgba(242, 230, 201, 0.76);
  margin-bottom: 2.5rem;
}

.timeline-wrap {
  position: relative;
  padding-left: 1.5rem;
  border-left: 1px solid var(--gray);
}

.timeline-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1.8rem;
}

.timeline-node {
  position: relative;
}

.timeline-node::before {
  content: "";
  position: absolute;
  left: calc(-1.5rem - 5px);
  top: 0.4rem;
  width: 10px;
  height: 10px;
  background: var(--purple);
  box-shadow: 0 0 12px var(--about-glow-purple), 0 0 24px var(--about-glow-purple);
}

.timeline-node:nth-child(4n + 2)::before {
  background: var(--blue);
  box-shadow: 0 0 12px var(--about-glow-blue);
}

.timeline-node:nth-child(4n + 3)::before {
  background: var(--pink);
  box-shadow: 0 0 12px var(--about-glow-pink);
}

.timeline-node:nth-child(4n + 4)::before {
  background: var(--yellow);
  box-shadow: 0 0 12px rgba(255, 209, 102, 0.3);
}

.timeline-node::after {
  content: "";
  position: absolute;
  left: calc(-1.5rem + 1px);
  top: 0.9rem;
  width: 1.5rem;
  height: 1px;
  background: var(--gray);
}

.timeline-year {
  font-family: var(--font-head);
  font-size: 1.45rem;
  font-weight: 700;
  line-height: 1;
  color: var(--yellow);
}

.timeline-card {
  margin-top: 0.45rem;
  max-width: 48em;
}

.timeline-card h3 {
  font-size: 1rem;
  font-weight: 700;
  margin: 0 0 0.25rem;
  color: var(--paper);
  transition: color 0.2s ease;
}

.timeline-card p {
  max-width: 30em;
  font-size: 0.85rem;
  line-height: 1.75;
  color: rgba(242, 230, 201, 0.66);
  margin: 0;
}

.timeline-node:hover .timeline-card h3 {
  color: var(--blue);
}

/* ---------- 团队与组织 ---------- */
.about-team {
  padding: 3rem 0;
  background: var(--panel);
}

.about-team .section-head {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.team-intro {
  max-width: 38em;
  line-height: 1.8;
  font-size: 0.95rem;
  color: rgba(242, 230, 201, 0.76);
}

.about-team-figure {
  margin: 1.8rem 0 0;
}

.about-team-figure img {
  filter: saturate(1.05) contrast(1.03);
}

.team-grid {
  display: grid;
  gap: 1rem;
  margin-top: 1.8rem;
}

.team-cell {
  position: relative;
  padding: 1.4rem 1.2rem;
  border: 1px solid var(--gray);
  background: var(--bg-ink);
}

.team-cell--ops { border-top: 3px solid var(--purple); }
.team-cell--dev { border-top: 3px solid var(--blue); }
.team-cell--sup { border-top: 3px solid var(--pink); }

.team-icon {
  font-size: 1.5rem;
  line-height: 1;
  margin-bottom: 0.7rem;
}

.team-cell--ops .team-icon { color: var(--purple); }
.team-cell--dev .team-icon { color: var(--blue); }
.team-cell--sup .team-icon { color: var(--pink); }

.team-cell h3 {
  font-size: 1.05rem;
  margin: 0 0 0.55rem;
  font-family: var(--font-head);
}

.team-cell p {
  max-width: 30em;
  font-size: 0.85rem;
  line-height: 1.75;
  color: rgba(242, 230, 201, 0.7);
  margin: 0;
}

.team-note {
  max-width: 44em;
  margin-top: 1.4rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  line-height: 1.7;
  color: rgba(242, 230, 201, 0.52);
}

/* ---------- 资质与认证 ---------- */
.about-credentials {
  padding: 3rem 0;
  background:
    radial-gradient(ellipse at 12% 88%, var(--about-glow-blue), transparent 40%),
    var(--bg-ink);
}

.about-credentials .section-head {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.credentials-grid {
  display: grid;
  gap: 2rem;
}

.about-credential-figure {
  margin: 0;
}

.about-credential-figure img {
  filter: saturate(0.92) contrast(1.05);
}

.credential-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.8rem;
}

.credential-item {
  display: flex;
  gap: 0.85rem;
  padding: 1rem;
  border: 1px solid var(--about-line-soft);
  background: rgba(22, 27, 38, 0.85);
}

.credential-mark {
  flex: 0 0 2rem;
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  font-size: 0.9rem;
  font-family: var(--font-mono);
  border-radius: 50%;
  border: 1px solid currentColor;
}

.credential-item strong {
  display: block;
  font-size: 0.95rem;
  font-family: var(--font-head);
  font-weight: 700;
}

.credential-item p {
  max-width: 30em;
  font-size: 0.8rem;
  line-height: 1.65;
  color: rgba(242, 230, 201, 0.65);
  margin: 0.25rem 0 0;
}

.credit-iso { color: var(--purple); }
.credit-psi { color: var(--blue); }
.credit-icp { color: var(--yellow); }
.credit-crypt { color: var(--pink); }

.credentials-note {
  margin-top: 1.6rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: rgba(242, 230, 201, 0.56);
  border-left: 2px solid var(--pink);
  padding-left: 0.8rem;
  max-width: 34em;
}

/* ---------- 用户规模与市场认可 ---------- */
.about-stats {
  padding: 3rem 0;
  border-top: 1px solid var(--gray);
  background:
    linear-gradient(140deg, rgba(177, 75, 255, 0.12), transparent 42%),
    linear-gradient(220deg, rgba(41, 197, 255, 0.1), transparent 38%),
    var(--bg-ink);
}

.about-stats .section-head {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.stats-intro {
  max-width: 40em;
  line-height: 1.8;
  font-size: 0.95rem;
  color: rgba(242, 230, 201, 0.76);
}

.stats-grid {
  display: grid;
  gap: 0.75rem;
  margin-top: 2rem;
}

.stat-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  padding: 1.2rem 1rem;
  border: 1px solid var(--gray);
  background: rgba(22, 27, 38, 0.92);
  overflow: hidden;
}

.stat-card::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 2px;
  background: var(--gray);
}

.stat-card--primary::after { background: var(--purple); }
.stat-card--yellow::after { background: var(--yellow); }
.stat-card--blue::after { background: var(--blue); }
.stat-card--pink::after { background: var(--pink); }
.stat-card--gold::after { background: var(--yellow); }
.stat-card--cyan::after { background: var(--blue); }

.stat-value {
  font-family: var(--font-head);
  font-size: clamp(1.35rem, 2.6vw, 2rem);
  font-weight: 700;
  line-height: 1.1;
  color: var(--paper);
}

.stat-card--primary .stat-value { color: var(--purple); }
.stat-card--yellow .stat-value { color: var(--yellow); }
.stat-card--blue .stat-value { color: var(--blue); }
.stat-card--pink .stat-value { color: var(--pink); }
.stat-card--gold .stat-value { color: var(--yellow); }
.stat-card--cyan .stat-value { color: var(--blue); }

.stat-label {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.08em;
  color: rgba(242, 230, 201, 0.58);
}

.stats-footer {
  margin-top: 1.8rem;
  max-width: 44em;
  font-size: 0.85rem;
  line-height: 1.8;
  color: rgba(242, 230, 201, 0.7);
}

.stats-footer a {
  color: var(--purple);
  text-decoration: none;
  border-bottom: 1px solid rgba(177, 75, 255, 0.4);
}

.stats-footer a:hover {
  color: var(--cyan, var(--blue));
  border-bottom-color: var(--blue);
}

/* ---------- 帮助引导 ---------- */
.about-help {
  padding: 2.5rem 0 4rem;
}

.about-help-inner {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.about-help h2 {
  font-family: var(--font-head);
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 0.5rem;
}

.about-help p {
  max-width: 30em;
  font-size: 0.9rem;
  line-height: 1.7;
  color: rgba(242, 230, 201, 0.74);
  margin: 0;
}

.about-help-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* ---------- 响应式增强 ---------- */
@media (min-width: 720px) {
  .about-hero {
    padding: 3.5rem 0 4.5rem;
  }

  .about-hero-code {
    font-size: 0.75rem;
  }

  .about-origin {
    padding: 4.5rem 0;
  }

  .about-origin-grid {
    grid-template-columns: 5fr 4fr;
    gap: 3.5rem;
    align-items: start;
  }

  .about-milestones,
  .about-team,
  .about-credentials,
  .about-stats {
    padding: 4.5rem 0;
  }

  .timeline-wrap {
    padding-left: 2.5rem;
  }

  .timeline-node::before {
    left: calc(-2.5rem - 5px);
  }

  .timeline-node::after {
    left: calc(-2.5rem + 1px);
    width: 2.5rem;
  }

  .timeline-year {
    font-size: 1.9rem;
  }

  .team-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
  }

  .credentials-grid {
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
  }

  .stats-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
  }

  .about-help {
    padding: 3.5rem 0 5.5rem;
  }

  .about-help-inner {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}

@media (min-width: 1080px) {
  .stats-grid {
    grid-template-columns: repeat(6, 1fr);
  }
}