/* ============ 平台介绍页 · page-about ============ */
.page-about {
  --ab-line: rgba(31, 94, 107, .18);
  --ab-shadow: 0 16px 34px rgba(14, 58, 68, .12);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero-grid {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
  align-items: start;
}

.page-about .about-hero-main h1 {
  margin-bottom: 18px;
}

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

.page-about .about-hero-side {
  position: relative;
  overflow: hidden;
  background: var(--deep);
  color: var(--sand);
  border-radius: var(--radius);
  padding: clamp(22px, 3vw, 32px);
}

.page-about .about-hero-side::after {
  content: "";
  position: absolute;
  top: -70px;
  right: -70px;
  width: 190px;
  height: 190px;
  border-radius: 50%;
  background: radial-gradient(circle at 40% 45%, rgba(224, 138, 46, .55), rgba(224, 138, 46, 0) 68%);
  pointer-events: none;
}

.page-about .about-side-title {
  margin: 0 0 18px;
  font-size: 12.5px;
  letter-spacing: .18em;
  color: var(--gold-lt);
}

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

.page-about .about-fact {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding-bottom: 13px;
  border-bottom: 1px solid rgba(246, 239, 227, .16);
}

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

.page-about .about-fact-num {
  flex: 0 0 auto;
  min-width: 84px;
  font-size: clamp(23px, 3vw, 28px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -.01em;
  color: var(--gold);
}

.page-about .about-fact-label {
  font-size: 14px;
  line-height: 1.55;
  color: rgba(246, 239, 227, .82);
}

/* ---------- 发展历程 ---------- */
.page-about .about-tl {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  background: var(--deep);
  color: var(--sand);
}

.page-about .about-tl-bg {
  position: absolute;
  inset: 0;
  z-index: -1;
}

.page-about .about-tl-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .38;
}

.page-about .about-tl-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(14, 58, 68, .88) 0%, rgba(14, 58, 68, .94) 60%, rgba(14, 58, 68, .99) 100%);
}

.page-about .about-tl-inner {
  position: relative;
  z-index: 1;
}

.page-about .about-tl-head {
  max-width: 46ch;
}

.page-about .about-tl .eyebrow {
  color: var(--gold-lt);
}

.page-about .about-tl .title-lg {
  color: var(--white);
}

.page-about .about-tl-lede {
  margin: 14px 0 0;
  max-width: 42ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: rgba(246, 239, 227, .76);
}

.page-about .tl-track {
  list-style: none;
  margin: clamp(30px, 5vw, 58px) 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .tl-node {
  position: relative;
  z-index: 1;
  padding: 20px 20px 22px 22px;
  background: rgba(246, 239, 227, .07);
  border-left: 3px solid var(--gold);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  transition: background var(--dur) var(--ease), transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .tl-node:hover,
.page-about .tl-node:focus-within {
  background: rgba(246, 239, 227, .13);
  border-left-color: var(--red);
  transform: translateX(5px);
}

.page-about .tl-year {
  margin: 0 0 8px;
  font-size: 12.5px;
  letter-spacing: .14em;
  color: var(--data);
}

.page-about .tl-stage {
  margin: 0 0 10px;
  font-size: clamp(18px, 2.4vw, 22px);
  font-weight: 800;
  line-height: 1.35;
  color: var(--white);
}

.page-about .tl-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(246, 239, 227, .76);
}

/* ---------- 服务覆盖 ---------- */
.page-about .about-reach-grid {
  display: grid;
  gap: clamp(30px, 4vw, 52px);
  align-items: center;
}

.page-about .about-reach-media {
  position: relative;
  padding: 0 0 20px 20px;
}

.page-about .about-reach-media::before {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 58%;
  height: 58%;
  border-radius: var(--radius);
  background: var(--gold);
}

.page-about .about-reach-media .figure {
  position: relative;
  z-index: 1;
}

.page-about .about-reach-body p {
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .reach-points {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .reach-point {
  display: grid;
  gap: 6px;
  padding-left: 16px;
  border-left: 2px solid var(--gold-lt);
}

.page-about .reach-point-key {
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--teal);
}

.page-about .reach-point-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

/* ---------- 工具地图 ---------- */
.page-about .about-tools {
  background: var(--teal-lt);
}

.page-about .about-tools-head {
  max-width: 54ch;
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .about-tools-lede {
  margin: 14px 0 0;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .tools-grid {
  display: grid;
  gap: 18px;
}

.page-about .tool-card {
  padding: 22px 22px 24px;
  background: var(--white);
  border: 1px solid var(--ab-line);
  border-radius: var(--radius);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .tool-card:hover,
.page-about .tool-card:focus-within {
  transform: translateY(-5px);
  border-color: var(--line-strong);
  box-shadow: var(--ab-shadow);
}

.page-about .tool-name {
  position: relative;
  margin: 0 0 12px;
  padding-left: 18px;
  font-size: clamp(18px, 2.2vw, 21px);
  font-weight: 800;
  line-height: 1.4;
  color: var(--teal);
}

.page-about .tool-name::before {
  content: "";
  position: absolute;
  left: 0;
  top: .58em;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--gold);
}

.page-about .tool-desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .tool-meta {
  margin: 16px 0 0;
  padding-top: 12px;
  border-top: 1px dashed var(--ab-line);
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--teal);
}

/* ---------- 团队与分工 ---------- */
.page-about .about-team-grid {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  align-items: center;
}

.page-about .about-team-body > p {
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .team-split {
  display: grid;
  gap: 16px;
  margin-top: 30px;
}

.page-about .team-split-item {
  padding: 20px 20px 22px;
  background: var(--white);
  border: 1px solid var(--ab-line);
  border-top: 3px solid var(--gold);
  border-radius: var(--radius-sm);
}

.page-about .team-split-item:nth-child(2) {
  border-top-color: var(--data);
}

.page-about .team-split-num {
  margin: 0;
  font-size: clamp(30px, 4vw, 38px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--gold);
}

.page-about .team-split-item:nth-child(2) .team-split-num {
  color: var(--data);
}

.page-about .team-split-label {
  margin: 8px 0 8px;
  font-size: 15px;
  font-weight: 800;
  color: var(--teal);
}

.page-about .team-split-text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.page-about .about-team-media {
  position: relative;
}

.page-about .about-team-media::after {
  content: "";
  position: absolute;
  right: -14px;
  top: -14px;
  width: 84px;
  height: 84px;
  border-radius: var(--radius-sm);
  background: var(--gold-lt);
  z-index: 0;
}

.page-about .about-team-media .figure {
  position: relative;
  z-index: 1;
}

/* ---------- 合作生态 ---------- */
.page-about .eco-panel {
  position: relative;
  overflow: hidden;
  padding: clamp(26px, 4vw, 50px);
  background: var(--white);
  border: 1px solid var(--ab-line);
  border-radius: clamp(16px, 3vw, 28px);
}

.page-about .eco-panel::before {
  content: "";
  position: absolute;
  right: -90px;
  bottom: -120px;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, rgba(224, 138, 46, .24), rgba(224, 138, 46, 0) 66%);
  pointer-events: none;
}

.page-about .eco-panel > p {
  position: relative;
  margin: 14px 0 0;
  max-width: 58ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .eco-list {
  position: relative;
  list-style: none;
  margin: clamp(24px, 3vw, 36px) 0 0;
  padding: 0;
  display: grid;
  gap: 20px;
}

.page-about .eco-item {
  display: grid;
  gap: 6px;
  padding-left: 16px;
  border-left: 2px solid var(--gold);
}

.page-about .eco-item-key {
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--red);
}

.page-about .eco-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

/* ---------- 更新节奏 ---------- */
.page-about .about-cadence {
  background: var(--deep);
  color: var(--sand);
}

.page-about .cadence-grid {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
  align-items: center;
}

.page-about .about-cadence .eyebrow {
  color: var(--gold-lt);
}

.page-about .about-cadence .title-lg {
  color: var(--white);
}

.page-about .cadence-body > p {
  margin: 14px 0 0;
  max-width: 46ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: rgba(246, 239, 227, .78);
}

.page-about .cadence-body .btn {
  margin-top: 26px;
}

.page-about .cadence-days {
  display: grid;
  gap: 16px;
}

.page-about .cadence-day {
  padding: 20px 22px;
  border: 1px solid rgba(246, 239, 227, .18);
  border-radius: var(--radius);
  background: rgba(246, 239, 227, .06);
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .cadence-day:hover,
.page-about .cadence-day:focus-within {
  background: rgba(246, 239, 227, .12);
  border-color: rgba(243, 194, 124, .6);
  transform: translateY(-4px);
}

.page-about .cadence-day-num {
  display: block;
  margin-bottom: 8px;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--gold);
}

.page-about .cadence-day-text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(246, 239, 227, .78);
}

/* ---------- 两类人群 ---------- */
.page-about .about-audience-title {
  max-width: 22ch;
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .audience-grid {
  display: grid;
  gap: 20px;
}

.page-about .audience-card {
  padding: 26px 24px 28px;
  background: var(--white);
  border: 1px solid var(--ab-line);
  border-radius: var(--radius);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .audience-card--alt {
  background: var(--sand);
}

.page-about .audience-card:hover,
.page-about .audience-card:focus-within {
  transform: translateY(-5px);
  border-color: var(--line-strong);
  box-shadow: var(--ab-shadow);
}

.page-about .audience-heading {
  margin: 14px 0 12px;
  font-size: clamp(19px, 2.3vw, 23px);
  font-weight: 800;
  line-height: 1.45;
  color: var(--teal);
}

.page-about .audience-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .audience-link {
  display: inline-block;
  margin-top: 20px;
  padding-bottom: 3px;
  font-size: 15px;
  font-weight: 700;
  color: var(--red);
  border-bottom: 2px solid rgba(211, 58, 44, .28);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .audience-link:hover,
.page-about .audience-link:focus-visible {
  color: var(--red-deep);
  border-bottom-color: var(--red-deep);
}

/* ---------- 媒体容器兜底 ---------- */
.page-about .media img,
.page-about .about-tl-bg img {
  max-width: 100%;
  height: auto;
}

.page-about .about-tl-bg img {
  height: 100%;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .team-split {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .audience-card--alt {
    margin-top: 34px;
  }

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

  .page-about .eco-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .about-reach-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }

  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .cadence-grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
  }

  .page-about .tools-grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    row-gap: 26px;
  }

  .page-about .tool-card:nth-child(1) {
    grid-column: 1 / span 5;
  }

  .page-about .tool-card:nth-child(2) {
    grid-column: 7 / span 6;
    margin-top: 36px;
  }

  .page-about .tool-card:nth-child(3) {
    grid-column: 1 / span 6;
    margin-top: 12px;
  }

  .page-about .tool-card:nth-child(4) {
    grid-column: 8 / span 5;
    margin-top: 48px;
  }

  .page-about .tool-card:nth-child(5) {
    grid-column: 2 / span 5;
    margin-top: 4px;
  }

  .page-about .tool-card:nth-child(6) {
    grid-column: 8 / span 5;
    margin-top: 40px;
  }

  /* 横向年份带 */
  .page-about .tl-track {
    display: flex;
    gap: 24px;
    overflow-x: auto;
    padding: 12px 4px 72px;
    scroll-snap-type: x proximity;
  }

  .page-about .tl-track::before {
    content: "";
    position: absolute;
    left: 6px;
    right: 6px;
    top: calc(50% + 16px);
    height: 2px;
    border-radius: 2px;
    background: linear-gradient(90deg, rgba(243, 194, 124, 0) 0%, rgba(243, 194, 124, .6) 18%, rgba(70, 167, 184, .6) 70%, rgba(70, 167, 184, 0) 100%);
    pointer-events: none;
    z-index: 0;
  }

  .page-about .tl-node {
    flex: 1 0 248px;
    max-width: 288px;
    scroll-snap-align: start;
    transform: translateY(-32px);
  }

  .page-about .tl-node:nth-child(even) {
    transform: translateY(32px);
  }

  .page-about .tl-node:hover,
  .page-about .tl-node:focus-within {
    transform: translateY(-38px);
  }

  .page-about .tl-node:nth-child(even):hover,
  .page-about .tl-node:nth-child(even):focus-within {
    transform: translateY(26px);
  }
}

@media (min-width: 1180px) {
  .page-about .about-reach-media {
    padding: 0 0 26px 26px;
  }

  .page-about .about-team-media::after {
    right: -22px;
    top: -22px;
    width: 110px;
    height: 110px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-node,
  .page-about .tool-card,
  .page-about .cadence-day,
  .page-about .audience-card,
  .page-about .audience-link {
    transition: none;
  }

  .page-about .tl-node,
  .page-about .tl-node:nth-child(even),
  .page-about .tl-node:hover,
  .page-about .tl-node:focus-within,
  .page-about .tool-card:hover,
  .page-about .tool-card:focus-within,
  .page-about .cadence-day:hover,
  .page-about .cadence-day:focus-within,
  .page-about .audience-card:hover,
  .page-about .audience-card:focus-within {
    transform: none;
  }
}