.page-about {
  --about-year-col: 60px;
  background: var(--ink);
  color: var(--paper);
  overflow-x: clip;
}

@media (min-width: 900px) {
  .page-about {
    --about-year-col: 96px;
  }
}

.page-about .about-h1,
.page-about .about-h2 {
  font-family: var(--font-display);
  letter-spacing: -0.02em;
  text-wrap: balance;
}

.page-about .about-h1 {
  font-weight: 900;
  font-size: clamp(32px, 7.4vw, 64px);
  line-height: 0.98;
  margin: 18px 0 22px;
}

.page-about .about-h2 {
  font-weight: 800;
  font-size: clamp(24px, 4.6vw, 38px);
  line-height: 1.06;
  margin: 14px 0 0;
}

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

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: 96px 0 52px;
  position: relative;
}

.page-about .about-hero-grid {
  display: grid;
  gap: 36px;
}

@media (min-width: 980px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: 56px;
    align-items: start;
  }
}

.page-about .about-lede {
  font-size: 16px;
  line-height: 1.85;
  color: var(--mist);
  max-width: 60ch;
  margin: 0;
}

.page-about .about-figures {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin: 30px 0 0;
  padding: 0;
}

.page-about .about-figure {
  background: var(--ink);
  padding: 14px 12px 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-figure-num {
  font-size: clamp(20px, 5vw, 30px);
  line-height: 1;
  color: var(--lime);
}

.page-about .about-figure-label {
  font-size: 12px;
  line-height: 1.4;
  color: var(--steel);
}

.page-about .about-visual {
  border: 1px solid var(--line);
  background:
    linear-gradient(158deg, var(--surface) 0%, rgba(18, 35, 29, 0.35) 52%, var(--ink) 100%);
  padding: 22px 20px 18px;
  position: relative;
}

.page-about .about-visual::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 64px;
  height: 2px;
  background: var(--lime);
}

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

.page-about .about-scale .scale-axis,
.page-about .about-scale .scale-tick {
  stroke: var(--line);
  stroke-width: 1;
}

.page-about .about-scale .scale-tick--live {
  stroke: var(--lime);
  stroke-width: 2;
}

.page-about .about-scale .scale-slant {
  stroke: var(--steel-dim);
  stroke-width: 1;
  stroke-dasharray: 3 5;
  opacity: 0.55;
}

.page-about .about-scale .scale-node {
  fill: none;
  stroke: var(--steel-dim);
  stroke-width: 1;
}

.page-about .about-scale .scale-node--warm {
  stroke: var(--orange);
}

.page-about .about-scale .scale-yr {
  fill: var(--steel);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
}

.page-about .about-scale .scale-yr--live {
  fill: var(--lime);
}

.page-about .about-visual .caption {
  margin: 10px 0 0;
}

/* ---------- 起点 ---------- */

.page-about .about-origin {
  padding: 56px 0;
  border-top: 1px solid var(--line);
}

@media (min-width: 900px) {
  .page-about .about-origin {
    padding: 76px 0;
  }
}

.page-about .about-origin-grid {
  display: grid;
  gap: 28px;
}

@media (min-width: 900px) {
  .page-about .about-origin-grid {
    grid-template-columns: minmax(0, 0.42fr) minmax(0, 0.58fr);
    gap: 48px;
  }
}

.page-about .about-origin-body p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--steel);
  margin: 0 0 16px;
  max-width: 62ch;
}

.page-about .about-note-row {
  display: grid;
  gap: 14px;
  margin-top: 26px;
}

@media (min-width: 640px) {
  .page-about .about-note-row {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .about-note-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.25;
  margin: 0 0 8px;
  color: var(--paper);
}

.page-about .about-note-text {
  font-size: 14px;
  line-height: 1.7;
  color: var(--steel);
  margin: 0;
}

/* ---------- 时间轴 ---------- */

.page-about .about-timeline {
  padding: 56px 0;
  background: var(--surface);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

@media (min-width: 900px) {
  .page-about .about-timeline {
    padding: 80px 0;
  }
}

.page-about .about-section-head {
  margin-bottom: 34px;
}

.page-about .about-section-lede {
  font-size: 15px;
  line-height: 1.85;
  color: var(--steel);
  max-width: 62ch;
  margin: 16px 0 0;
}

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

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

.page-about .about-stage > summary {
  display: grid;
  grid-template-columns: var(--about-year-col) minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 18px 0;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-stage > summary:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 3px;
}

.page-about .about-year {
  font-size: 13px;
  line-height: 1.5;
  letter-spacing: 0.04em;
  color: var(--steel);
  align-self: stretch;
  border-right: 1px solid var(--line);
  padding-right: 10px;
  position: relative;
  text-align: left;
}

.page-about .about-year::after {
  content: "";
  position: absolute;
  top: 6px;
  right: -4px;
  width: 7px;
  height: 7px;
  background: var(--surface);
  border: 1px solid var(--steel-dim);
}

.page-about .about-stage[open] .about-year::after {
  background: var(--lime);
  border-color: var(--lime);
}

.page-about .about-stage-head {
  display: block;
  min-width: 0;
}

.page-about .about-stage-title {
  display: block;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(18px, 3.6vw, 25px);
  line-height: 1.22;
  letter-spacing: -0.01em;
  margin-top: 8px;
  color: var(--paper);
}

.page-about .about-stage-toggle {
  display: inline-block;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--steel-dim);
}

.page-about .about-stage-toggle::after {
  content: "展开 +";
}

.page-about .about-stage[open] .about-stage-toggle::after {
  content: "收起 −";
}

.page-about .about-stage > summary:hover .about-stage-toggle {
  color: var(--lime);
}

.page-about .about-stage-body {
  padding: 0 0 26px calc(var(--about-year-col) + 14px);
}

.page-about .about-stage-body p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--steel);
  margin: 0;
  max-width: 62ch;
}

@media (min-width: 900px) {
  .page-about .about-stage-body {
    padding-right: 48px;
  }
}

/* ---------- 团队 ---------- */

.page-about .about-team {
  padding: 56px 0;
}

@media (min-width: 900px) {
  .page-about .about-team {
    padding: 84px 0;
  }
}

.page-about .about-team-grid {
  display: grid;
  gap: 30px;
}

@media (min-width: 900px) {
  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 0.46fr) minmax(0, 0.54fr);
    gap: 52px;
    align-items: start;
  }
}

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

.page-about .about-team-media .media {
  border: 1px solid var(--line);
}

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

.page-about .about-team-media .caption {
  margin: 10px 0 0;
}

.page-about .about-team-copy p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--steel);
  max-width: 62ch;
  margin: 16px 0 0;
}

.page-about .about-roles {
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin: 28px 0 0;
  padding: 0;
}

@media (min-width: 640px) {
  .page-about .about-roles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .about-role {
  background: var(--surface-2);
  padding: 16px 14px;
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.page-about .about-role-num {
  font-size: 22px;
  line-height: 1;
  color: var(--lime);
}

.page-about .about-role-name {
  font-size: 14px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .about-role-desc {
  font-size: 12px;
  line-height: 1.55;
  color: var(--steel);
}

/* ---------- 更新节奏 ---------- */

.page-about .about-cadence {
  padding: 56px 0;
  background: var(--surface);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

@media (min-width: 900px) {
  .page-about .about-cadence {
    padding: 80px 0;
  }
}

.page-about .about-tape {
  list-style: none;
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(220px, 78%);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin: 0;
  padding: 0;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-tape-card {
  background: var(--ink);
  padding: 20px 18px 22px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  scroll-snap-align: start;
}

.page-about .about-tape-clock {
  font-size: 20px;
  line-height: 1.1;
  color: var(--lime);
  letter-spacing: 0.02em;
}

.page-about .about-tape-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.25;
  color: var(--paper);
}

.page-about .about-tape-text {
  font-size: 13px;
  line-height: 1.7;
  color: var(--steel);
}

@media (min-width: 820px) {
  .page-about .about-tape {
    grid-auto-flow: row;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    overflow-x: visible;
  }
}

/* ---------- 合作生态 ---------- */

.page-about .about-partners {
  padding: 56px 0;
}

@media (min-width: 900px) {
  .page-about .about-partners {
    padding: 84px 0;
  }
}

.page-about .about-partners-grid {
  display: grid;
  gap: 34px;
}

@media (min-width: 940px) {
  .page-about .about-partners-grid {
    grid-template-columns: minmax(0, 0.52fr) minmax(0, 0.48fr);
    gap: 52px;
    align-items: start;
  }
}

.page-about .about-partners-lead p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--steel);
  max-width: 60ch;
  margin: 16px 0 0;
}

.page-about .about-partners-lead .btn {
  margin-top: 26px;
}

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

@media (min-width: 560px) {
  .page-about .about-partner-cards {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .about-partner-card {
  background: var(--surface);
  padding: 18px 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  border-left: 3px solid transparent;
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.page-about .about-partner-card:hover,
.page-about .about-partner-card:focus-within {
  border-left-color: var(--lime);
  background: var(--surface-2);
}

.page-about .about-partner-card--warm:hover,
.page-about .about-partner-card--warm:focus-within {
  border-left-color: var(--orange);
}

.page-about .about-partner-num {
  font-size: 22px;
  line-height: 1;
  color: var(--paper);
}

.page-about .about-partner-card--warm .about-partner-num {
  color: var(--orange);
}

.page-about .about-partner-name {
  font-size: 14px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .about-partner-desc {
  font-size: 12px;
  line-height: 1.65;
  color: var(--steel);
}

/* ---------- 内容方法 ---------- */

.page-about .about-method {
  padding: 56px 0;
  background: var(--mist);
  color: var(--ink);
}

@media (min-width: 900px) {
  .page-about .about-method {
    padding: 84px 0;
  }
}

.page-about .about-method .about-h2 {
  color: var(--ink);
}

.page-about .about-method-grid {
  display: grid;
  gap: 30px;
}

@media (min-width: 900px) {
  .page-about .about-method-grid {
    grid-template-columns: minmax(0, 0.4fr) minmax(0, 0.6fr);
    gap: 52px;
    align-items: start;
  }
}

.page-about .about-method .eyebrow {
  color: var(--lime-dark);
}

.page-about .about-method-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--mist-2);
}

.page-about .about-method-item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 14px;
  padding: 20px 0;
  border-bottom: 1px solid var(--mist-2);
}

.page-about .about-method-num {
  font-size: 15px;
  line-height: 1.6;
  color: var(--lime-dark);
}

.page-about .about-method-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(18px, 3.4vw, 22px);
  line-height: 1.25;
  margin: 0 0 8px;
  color: var(--ink);
}

.page-about .about-method-text {
  font-size: 14px;
  line-height: 1.85;
  color: #40514A;
  margin: 0;
  max-width: 58ch;
}

/* ---------- 下一阶段 ---------- */

.page-about .about-next {
  padding: 56px 0;
}

@media (min-width: 900px) {
  .page-about .about-next {
    padding: 84px 0;
  }
}

.page-about .about-next-inner {
  border: 1px solid var(--line);
  padding: 28px 20px 30px;
  background:
    linear-gradient(200deg, rgba(201, 255, 61, 0.07) 0%, rgba(10, 13, 12, 0) 46%),
    var(--ink);
  position: relative;
}

.page-about .about-next-inner::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 90px;
  height: 2px;
  background: var(--lime);
}

@media (min-width: 760px) {
  .page-about .about-next-inner {
    padding: 36px 32px 38px;
  }
}

.page-about .about-next-head p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--steel);
  max-width: 62ch;
  margin: 16px 0 0;
}

.page-about .about-next-cards {
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin: 30px 0 0;
  padding: 0;
}

@media (min-width: 760px) {
  .page-about .about-next-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .about-next-card {
  background: var(--surface);
  padding: 18px 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .about-next-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.28;
  margin: 0;
  color: var(--paper);
}

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

/* ---------- 结尾 ---------- */

.page-about .about-close {
  padding: 0 0 64px;
}

.page-about .about-close-figure {
  margin: 0 0 28px;
  position: relative;
  border: 1px solid var(--line);
}

.page-about .about-close-figure::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(10, 13, 12, 0.1) 0%, rgba(10, 13, 12, 0.72) 100%);
  pointer-events: none;
}

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

.page-about .about-close-body p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--steel);
  max-width: 60ch;
  margin: 16px 0 0;
}

@media (min-width: 900px) {
  .page-about .about-close {
    padding: 0 0 88px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-partner-card {
    transition: none;
  }
}