/* ================================================================
   关于平台 · about.css  —  作用域 body.about-page
   说明：所有样式限定在 .about-page 内，不重命名公共组件，
        不影响寻水脉 / 读水文 / 悟水德 / 游水境 / 创水礼。
   ================================================================ */

/* ---- 页面级设计令牌（仅作用于本页） ---- */
.about-page {
  --about-paper: #F5F1E8;
  --about-water: #E7F1EF;
  --about-water-light: #F2F7F5;
  --about-teal-dark: #123F3D;
  --about-teal: #17655F;
  --about-muted: #687775;
  --about-gold: #C6A15B;
  --about-gold-light: #E2D1A5;
  --about-border: rgba(23, 101, 95, 0.16);
  --about-shadow: 0 16px 42px rgba(36, 66, 62, 0.08);

  --motion-fast: 180ms;
  --motion-base: 320ms;

  /* 保留原“关于平台”底色（金缕蓝烟 subtle 纹理叠于米白之上） */
  background:
    url('../images/金缕蓝烟.jpg') center/cover no-repeat fixed,
    var(--about-paper);
  background-blend-mode: soft-light;
}

.about-page :focus-visible {
  outline: 2px solid var(--about-teal);
  outline-offset: 2px;
}
.about-page ::selection { background: rgba(23, 101, 95, 0.16); }

/* 锚点滚动避开吸顶导航（导航为 sticky，不覆盖正文，仅锚点需偏移） */
.about-page [id] { scroll-margin-top: 88px; }

/* ================================================================
   主体区块（页面信息架构）
   区块顺序：hero → theme → question → values → modules →
            sample → method → vision → explore
   ================================================================ */

/* 通用区块骨架 */
.about-page .ab-section { padding: var(--section-space) 0; }
.about-page .ab-section-alt {
  background: rgba(231, 241, 239, 0.5);
}

.about-page .ab-sec-head {
  max-width: 780px;
  margin: 0 0 48px;
}
.about-page .ab-sec-head--center {
  text-align: center;
  margin-inline: auto;
}
.about-page .ab-sec-head--center .ab-kicker {
  justify-content: center;
}
.about-page .ab-sec-head--left {
  text-align: left;
}
.about-page .ab-sec-title {
  margin-top: 14px;
}
.about-page .ab-sec-lead {
  margin-top: 16px;
  font-size: 16px;
}
.about-page .ab-sec-note {
  max-width: 780px;
  margin: 40px auto 0;
  padding: 16px 24px;
  text-align: center;
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--about-border);
  border-left: 3px solid var(--about-gold);
  border-radius: 12px;
}

/* 正文段落 */
.about-page .ab-prose {
  max-width: 760px;
  margin: 0 auto;
}
.about-page .ab-prose p {
  margin-bottom: 18px;
}
.about-page .ab-prose p:last-child { margin-bottom: 0; }

/* 地方样本：南京样本与四种水德的简洁对应 */
.about-page .ab-sample-map {
  max-width: 900px;
  margin: 44px auto 0;
  padding: 24px 28px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--about-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}
.about-page .ab-sample-map-title {
  text-align: center;
  margin-bottom: 18px;
}
.about-page .ab-sample-map-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.about-page .ab-sample-map-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  align-items: center;
  text-align: center;
  padding: 8px 0;
}
.about-page .ab-sample-map-item span {
  font-size: 14px;
  line-height: 1.7;
  color: var(--about-muted);
}
.about-page .ab-sample-map-item a {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--about-teal);
  text-decoration: none;
}
.about-page .ab-sample-map-item a:hover {
  color: var(--about-gold);
}

/* ---- 赛题回应：编辑式布局（左侧命题标题 + 右侧正文） ---- */
.about-page .ab-editorial-grid {
  display: grid;
  grid-template-columns: minmax(250px, 5fr) 7fr;
  gap: 56px;
  align-items: start;
}
.about-page .ab-editorial-head {
  padding-top: 6px;
}
.about-page .ab-editorial-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 84px;
  height: 84px;
  margin: 20px 0 18px;
  border-radius: 50%;
  border: 2px solid var(--about-border);
  background: rgba(255, 255, 255, 0.55);
  box-shadow: var(--about-shadow);
}
.about-page .ab-editorial-body p {
  margin-bottom: 20px;
}
.about-page .ab-editorial-body p:last-child { margin-bottom: 0; }

/* 平台自述：浅水青渐变卡 + 顶部金色水线 + 水字水印（居中） */
.about-page .ab-theme-quote {
  position: relative;
  max-width: 760px;
  margin: 56px auto 0;
  padding: 34px 44px 30px;
  background:
    radial-gradient(520px 200px at 100% 0%, rgba(198, 161, 91, 0.09), transparent 70%),
    linear-gradient(135deg, var(--about-water-light) 0%, rgba(242, 247, 245, 0.55) 100%);
  border: 1px solid var(--about-border);
  border-radius: 16px;
  box-shadow: var(--shadow-card);
  text-align: center;
  overflow: hidden;
}
.about-page .ab-theme-quote::before {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--about-gold), rgba(198, 161, 91, 0.18));
}
.about-page .ab-theme-quote::after {
  content: '水';
  position: absolute;
  right: -8px;
  bottom: -36px;
  font-family: var(--font-display);
  font-size: 128px;
  font-weight: 900;
  line-height: 1;
  color: rgba(23, 101, 95, 0.06);
  pointer-events: none;
}
.about-page .ab-theme-quote .ds-cite-label {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 5px 18px;
  border-radius: 999px;
  background: rgba(198, 161, 91, 0.14);
  border: 1px solid rgba(198, 161, 91, 0.42);
  color: var(--about-gold);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 4px;
  margin-bottom: 14px;
}
.about-page .ab-theme-quote .ds-quote {
  position: relative;
  margin: 0;
  font-family: var(--font-display);
  font-size: 22px;
  line-height: 1.9;
  letter-spacing: 1px;
  color: var(--about-teal-dark);
}

/* ---- Hero：根植生态文化，走向共同家园 ---- */
.about-page .ab-hero {
  position: relative;
  overflow: hidden;
  padding: var(--section-space) 0 calc(var(--section-space) - 24px);
  background:
    radial-gradient(900px 420px at 6% 0%, rgba(23, 101, 95, 0.05) 0%, transparent 62%),
    radial-gradient(720px 360px at 94% 100%, rgba(198, 161, 91, 0.07) 0%, transparent 64%),
    linear-gradient(180deg, var(--about-water-light) 0%, var(--about-paper) 100%);
  min-height: clamp(560px, 74vh, 680px);
  display: grid;
  align-items: center;
}
.about-page .ab-hero-inner {
  display: grid;
  grid-template-columns: 55fr 45fr;
  gap: clamp(36px, 4vw, 56px);
  align-items: center;
  width: 100%;
  max-width: var(--page-max);
  margin-inline: auto;
}
.about-page .ab-hero-copy {
  max-width: 560px;
  justify-self: start;
}
.about-page .ab-hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 20px;
  animation: abHeroFadeUp 480ms var(--ease-out) 0ms both;
}
.about-page .ab-hero-title {
  margin-bottom: 20px;
  max-width: none;
}
.about-page .ab-hero-line { display: inline; }
.about-page .ab-hero-line-1 { animation: abHeroFadeUp 520ms var(--ease-out) 80ms both; }
.about-page .ab-hero-line-2 { animation: abHeroFadeUp 520ms var(--ease-out) 200ms both; }
.about-page .ab-hero-sub {
  margin-bottom: 14px;
  animation: abHeroFadeUp 520ms var(--ease-out) 340ms both;
}
.about-page .ab-hero-desc {
  max-width: 540px;
  margin-bottom: 30px;
  animation: abHeroFadeUp 520ms var(--ease-out) 420ms both;
}
.about-page .ab-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  animation: abHeroFadeUp 520ms var(--ease-out) 520ms both;
}
.about-page .ab-hero-btn { min-height: 44px; border-radius: 8px; }
.about-page .ab-hero-btn-primary {
  background: var(--about-teal);
  color: #fff;
}
.about-page .ab-hero-btn-primary:hover {
  background: var(--about-teal-dark);
  box-shadow: 0 6px 18px rgba(23, 101, 95, 0.28);
}
.about-page .ab-hero-btn-ghost {
  background: transparent;
  color: var(--about-teal);
  border: 1px solid rgba(23, 101, 95, 0.32);
}
.about-page .ab-hero-btn-ghost:hover {
  border-color: var(--about-teal);
  background: rgba(23, 101, 95, 0.06);
}

/* 右侧配图 */
.about-page .ab-hero-figure {
  margin: 0;
  width: 100%;
  max-width: 560px;
  justify-self: end;
  animation: abHeroImgIn 620ms var(--ease-out) 160ms both;
}
.about-page .ab-hero-media {
  position: relative;
  width: 100%;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background:
    radial-gradient(120% 90% at 30% 20%, #FDFEFC 0%, var(--about-water-light) 55%, var(--about-water) 100%);
  border: 1px solid var(--about-border);
  box-shadow: var(--shadow-card);
}
.about-page .ab-hero-media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
@media (max-width: 600px) {
  .about-page .ab-hero-media {
    min-height: 240px;
  }
}
.about-page .ab-hero-fade {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 42%;
  background: linear-gradient(180deg, rgba(231, 241, 239, 0) 0%, rgba(231, 241, 239, 0.5) 55%, rgba(231, 241, 239, 0.92) 100%);
  pointer-events: none;
}
.about-page .ab-hero-ripple {
  display: block;
  width: 100%;
  height: 34px;
  margin-top: 2px;
  animation: abHeroRipple 16s ease-in-out infinite;
}
.about-page .ab-hero-caption {
  margin-top: 10px;
  text-align: center;
}

@keyframes abHeroFadeUp {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: none; }
}
@keyframes abHeroImgIn {
  from { opacity: 0; transform: translateX(24px); }
  to   { opacity: 1; transform: none; }
}
@keyframes abHeroRipple {
  0%, 100% { transform: translateX(0); }
  50%      { transform: translateX(-18px); }
}

/* ---- 核心命题：四段横向水脉（about-flow） ---- */
.about-page .ab-flow {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 26px;
  padding-top: 14px;
}
/* 中间水流线：穿过编号圆环中心的横向轨道 */
.about-page .ab-flow-track {
  position: absolute;
  top: 42px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--about-border);
  transform: translateY(-50%);
  pointer-events: none;
}
.about-page .ab-flow-track-fill,
.about-page .ab-flow-track-flow {
  position: absolute;
  inset: 0;
}
/* 绘制层：滚动进入时从左向右画出 */
.about-page .ab-flow-track-fill {
  background: linear-gradient(90deg, rgba(23, 101, 95, 0.65), rgba(23, 101, 95, 0.32));
  background-repeat: no-repeat;
  background-position: left center;
  background-size: 0% 100%;
  transition: background-size 0.7s ease 0.15s;
}
.about-page .ab-flow.in-view .ab-flow-track-fill {
  background-size: 100% 100%;
}
/* 流动层：hover 时产生低透明度流动 */
.about-page .ab-flow-track-flow {
  background: linear-gradient(90deg, transparent 0%, rgba(198, 161, 91, 0.55) 50%, transparent 100%);
  background-size: 50% 100%;
  background-repeat: no-repeat;
  background-position: -100% 0;
  opacity: 0;
  transition: opacity 0.3s ease;
}
.about-page .ab-flow:hover .ab-flow-track-flow {
  opacity: 0.5;
  animation: abFlowSweep 16s linear infinite;
}
@keyframes abFlowSweep {
  from { background-position: -100% 0; }
  to { background-position: 100% 0; }
}

/* 四个面向：编号圆环 + 内容（不入厚重卡片） */
.about-page .ab-flow-item {
  position: relative;
  --d: 0ms;
}
.about-page .ab-flow-item:nth-of-type(2) { --d: 160ms; }
.about-page .ab-flow-item:nth-of-type(3) { --d: 320ms; }
.about-page .ab-flow-item:nth-of-type(4) { --d: 480ms; }

.about-page .ab-flow-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--about-paper);
  border: 2px solid var(--about-teal);
  box-shadow: 0 6px 16px rgba(36, 66, 62, 0.1);
  opacity: 0;
  transform: scale(0.6);
}
.about-page .ab-flow.in-view .ab-flow-item:not(:hover) .ab-flow-num {
  opacity: 1;
  transform: scale(1);
  transition:
    opacity 0.5s ease var(--d),
    transform 0.5s cubic-bezier(0.22, 1, 0.36, 1) var(--d),
    border-color var(--motion-base),
    color var(--motion-base),
    box-shadow var(--motion-base);
}
.about-page .ab-flow.in-view .ab-flow-item:hover .ab-flow-num {
  opacity: 1;
  transform: translateY(-3px);
  border-color: var(--about-gold);
  color: var(--about-gold);
  box-shadow: 0 10px 22px rgba(198, 161, 91, 0.22);
  transition: all var(--motion-fast);
}

.about-page .ab-flow-cat {
  margin: 18px 0 8px;
  opacity: 0;
  transform: translateY(14px);
}
.about-page .ab-flow-title {
  margin-bottom: 10px;
  opacity: 0;
  transform: translateY(14px);
}
.about-page .ab-flow-desc {
  opacity: 0;
  transform: translateY(14px);
}
.about-page .ab-flow.in-view .ab-flow-cat,
.about-page .ab-flow.in-view .ab-flow-title,
.about-page .ab-flow.in-view .ab-flow-desc {
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 0.6s ease calc(var(--d) + 220ms),
    transform 0.6s ease calc(var(--d) + 220ms);
}

/* ---- 四个价值面向 ---- */
.about-page .ab-value-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}
.about-page .ab-value-card {
  padding: 4px 0;
}
.about-page .ab-value-tag {
  display: inline-block;
  background: rgba(23, 101, 95, 0.08);
  border-radius: 9999px;
  padding: 4px 12px;
}
.about-page .ab-value-title {
  margin: 16px 0 10px;
}

/* ---- 数字文化路径：五张横向模块卡片（about-path） ---- */
.about-page .ab-path {
  position: relative;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
  padding-top: 20px;
}
/* 横向水流线：穿过节点圆环中心 */
.about-page .ab-path-rail {
  position: absolute;
  top: 56px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--about-border);
  transform: translateY(-50%);
  pointer-events: none;
}
.about-page .ab-path-rail-fill,
.about-page .ab-path-rail-flow {
  position: absolute;
  inset: 0;
}
/* 绘制层：滚动进入时从左向右画出 */
.about-page .ab-path-rail-fill {
  background: linear-gradient(90deg, rgba(23, 101, 95, 0.6), rgba(23, 101, 95, 0.3));
  background-repeat: no-repeat;
  background-position: left center;
  background-size: 0% 100%;
  transition: background-size 0.7s ease 0.15s;
}
.about-page .ab-path.in-view .ab-path-rail-fill {
  background-size: 100% 100%;
}
/* 流动层：hover 时产生低透明度流动 */
.about-page .ab-path-rail-flow {
  background: linear-gradient(90deg, transparent 0%, rgba(198, 161, 91, 0.55) 50%, transparent 100%);
  background-size: 50% 100%;
  background-repeat: no-repeat;
  background-position: -100% 0;
  opacity: 0;
  transition: opacity 0.3s ease;
}
.about-page .ab-path:hover .ab-path-rail-flow {
  opacity: 0.5;
  animation: abPathFlowH 16s linear infinite;
}
@keyframes abPathFlowH {
  from { background-position: -100% 0; }
  to { background-position: 100% 0; }
}

/* 模块卡片 */
.about-page .ab-path-card {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 16px 18px 18px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.9), rgba(255, 255, 255, 0.55));
  border: 1px solid var(--about-border);
  border-radius: 16px;
  box-shadow: var(--shadow-card);
  transition: transform var(--motion-base) var(--ease-out),
              box-shadow var(--motion-base) var(--ease-out),
              border-color var(--motion-base) var(--ease-out);
}
.about-page .ab-path-card:hover {
  transform: translateY(-4px);
  border-color: rgba(198, 161, 91, 0.42);
  box-shadow: 0 18px 36px -18px rgba(23, 101, 95, 0.25);
}
.about-page .ab-path-node {
  position: relative;
  z-index: 1;
  width: 40px;
  height: 40px;
  margin-bottom: 14px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--about-paper);
  border: 2px solid var(--about-gold);
  box-shadow: 0 4px 12px rgba(198, 161, 91, 0.16);
  opacity: 0;
  transform: scale(0.6);
}
.about-page .ab-path.in-view .ab-path-card:not(:hover) .ab-path-node {
  opacity: 1;
  transform: scale(1);
  transition:
    opacity 0.5s ease var(--d),
    transform 0.5s cubic-bezier(0.22, 1, 0.36, 1) var(--d),
    border-color var(--motion-base),
    box-shadow var(--motion-base);
}
.about-page .ab-path.in-view .ab-path-card:hover .ab-path-node {
  opacity: 1;
  transform: translateY(-2px);
  background: var(--about-gold);
  border-color: var(--about-gold);
  box-shadow: 0 6px 16px rgba(198, 161, 91, 0.25);
  transition: all var(--motion-fast);
}
.about-page .ab-path.in-view .ab-path-card:hover .ab-path-num {
  color: var(--about-paper);
}

.about-page .ab-path-card { --d: 0ms; }
.about-page .ab-path-card:nth-of-type(2) { --d: 140ms; }
.about-page .ab-path-card:nth-of-type(3) { --d: 280ms; }
.about-page .ab-path-card:nth-of-type(4) { --d: 420ms; }
.about-page .ab-path-card:nth-of-type(5) { --d: 560ms; }

.about-page .ab-path-title {
  margin-bottom: 6px;
}
.about-page .ab-path-pos {
  margin: 0 0 10px;
  font-size: 12px;
  line-height: 1.7;
}
.about-page .ab-path-pos span {
  display: block;
  color: var(--about-gold);
  font-weight: 700;
  letter-spacing: 2px;
  margin-bottom: 2px;
}
.about-page .ab-path-desc {
  flex: 1;
  margin: 0 0 10px;
  font-size: 13px;
  line-height: 1.8;
  color: var(--about-muted);
}
.about-page .ab-path-side {
  margin: 0 0 6px;
}
.about-page .ab-path-side-label {
  display: inline-block;
  margin-bottom: 4px;
  background: rgba(23, 101, 95, 0.08);
  border-radius: 999px;
  padding: 2px 10px;
  color: var(--about-teal);
  letter-spacing: 1px;
}
.about-page .ab-path-side-text {
  display: block;
  font-size: 12px;
  line-height: 1.7;
  color: var(--about-muted);
}
.about-page .ab-path-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 8px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 2px;
  color: var(--about-teal);
  text-decoration: none;
  padding: 4px 0 6px;
  border-bottom: 1px solid var(--about-border);
}
.about-page .ab-path-link:hover {
  color: var(--about-gold);
  border-color: var(--about-gold);
}
.about-page .ab-path-arrow {
  transition: transform var(--motion-fast);
}
.about-page .ab-path-link:hover .ab-path-arrow {
  transform: translateX(3px);
}

/* 入场：标题/定位/说明/入口/作用依次淡入 */
.about-page .ab-path-title,
.about-page .ab-path-pos,
.about-page .ab-path-desc,
.about-page .ab-path-link,
.about-page .ab-path-side {
  opacity: 0;
  transform: translateY(14px);
}
.about-page .ab-path.in-view .ab-path-title,
.about-page .ab-path.in-view .ab-path-pos,
.about-page .ab-path.in-view .ab-path-desc,
.about-page .ab-path.in-view .ab-path-link,
.about-page .ab-path.in-view .ab-path-side {
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 0.6s ease calc(var(--d) + 200ms),
    transform 0.6s ease calc(var(--d) + 200ms);
}
.about-page .ab-path.in-view .ab-path-link:hover {
  transition: color var(--motion-fast), border-color var(--motion-fast);
}

/* ---- 地方样本：一条从地方样本向外扩散的水流线（about-delta） ---- */
.about-page .ab-delta {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
  padding-top: 10px;
}
/* 中心样本：南京（一个入口，不是结论） */
.about-page .ab-delta-root {
  position: relative;
  z-index: 2;
  width: 132px;
  height: 132px;
  margin: 0 auto 0;
  border-radius: 50%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: var(--about-paper);
  border: 2px solid var(--about-teal);
  box-shadow: var(--about-shadow);
}
.about-page .ab-delta-root-name {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 900;
  color: var(--about-teal-dark);
  letter-spacing: 6px;
  margin-top: 6px;
}

/* 扩散水流线 + 节点画布 */
.about-page .ab-delta-map {
  position: relative;
  height: 232px;
}
.about-page .ab-delta-svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}
.about-page .ab-delta-line {
  fill: none;
  stroke: rgba(23, 101, 95, 0.55);
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-dasharray: 1;
  stroke-dashoffset: 1;
}
.about-page .ab-delta.in-view .ab-delta-line {
  stroke-dashoffset: 0;
  transition: stroke-dashoffset 0.7s ease 0.2s;
}

/* 五个低调观察节点：圆点居上、文字在圆点下方（不与线条重叠） */
.about-page .ab-delta-nodes {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px 0;
}
.about-page .ab-delta-node {
  text-align: center;
  --d: 0ms;
}
.about-page .ab-delta-node:nth-of-type(2) { --d: 140ms; }
.about-page .ab-delta-node:nth-of-type(3) { --d: 280ms; }
.about-page .ab-delta-node:nth-of-type(4) { --d: 420ms; }
.about-page .ab-delta-node:nth-of-type(5) { --d: 560ms; }
.about-page .ab-delta-dot {
  display: block;
  width: 12px;
  height: 12px;
  margin: 0 auto 10px;
  border-radius: 50%;
  background: var(--about-paper);
  border: 2px solid var(--about-teal);
}
.about-page .ab-delta-title {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  color: var(--about-teal-dark);
  letter-spacing: 1.5px;
  line-height: 1.7;
  min-height: 3em;
  display: flex;
  align-items: center;
  justify-content: center;
}
.about-page .ab-delta-place {
  display: inline-block;
  margin-top: 6px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 3px;
  color: var(--about-gold);
}

/* 入场：节点依次淡入 */
.about-page .ab-delta-node {
  opacity: 0;
  transform: translateY(12px);
}
.about-page .ab-delta.in-view .ab-delta-node {
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 0.6s ease calc(var(--d) + 600ms),
    transform 0.6s ease calc(var(--d) + 600ms);
}

/* ---- 表达方法：四个方法沿水流线排列（about-method-line） ---- */
.about-page .ab-method-line {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 26px;
  padding-top: 14px;
}
/* 中间水流线：穿过编号圆环中心 */
.about-page .ab-method-track {
  position: absolute;
  top: 34px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--about-border);
  transform: translateY(-50%);
  pointer-events: none;
}
.about-page .ab-method-track-fill {
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, rgba(23, 101, 95, 0.6), rgba(23, 101, 95, 0.3));
  background-repeat: no-repeat;
  background-position: left center;
  background-size: 0% 100%;
  transition: background-size 0.7s ease 0.15s;
}
.about-page .ab-method-line.in-view .ab-method-track-fill {
  background-size: 100% 100%;
}

/* 方法项：编号点亮 + 关键词 + 短标题 + 说明 */
.about-page .ab-method-item {
  text-align: center;
  --d: 0ms;
}
.about-page .ab-method-item:nth-of-type(2) { --d: 160ms; }
.about-page .ab-method-item:nth-of-type(3) { --d: 320ms; }
.about-page .ab-method-item:nth-of-type(4) { --d: 480ms; }

.about-page .ab-method-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--about-paper);
  border: 2px solid var(--about-gold);
  color: var(--about-gold);
  box-shadow: 0 4px 12px rgba(198, 161, 91, 0.16);
  opacity: 0;
  transform: scale(0.6);
  transition:
    opacity 0.5s ease var(--d),
    transform 0.5s cubic-bezier(0.22, 1, 0.36, 1) var(--d),
    background-color 0.4s ease var(--d),
    color 0.4s ease var(--d),
    border-color 0.4s ease var(--d);
}
.about-page .ab-method-line.in-view .ab-method-item:not(:hover) .ab-method-num {
  opacity: 1;
  transform: scale(1);
  background: var(--about-paper);
  border-color: var(--about-gold);
  color: var(--about-gold);
  box-shadow: 0 6px 16px rgba(198, 161, 91, 0.16);
}
.about-page .ab-method-line.in-view .ab-method-item:hover .ab-method-num {
  opacity: 1;
  transform: translateY(-3px);
  background: var(--about-gold);
  border-color: var(--about-gold);
  color: var(--about-paper);
  box-shadow: 0 8px 18px rgba(198, 161, 91, 0.28);
  transition: all var(--motion-fast);
}

.about-page .ab-method-tag {
  display: inline-block;
  margin-top: 18px;
  padding: 5px 12px;
  border: 1px solid rgba(198, 161, 91, 0.45);
  border-radius: 999px;
  opacity: 0;
  transform: translateY(14px);
}
.about-page .ab-method-title {
  margin: 12px 0 10px;
  opacity: 0;
  transform: translateY(14px);
}
.about-page .ab-method-desc {
  opacity: 0;
  transform: translateY(14px);
}
.about-page .ab-method-line.in-view .ab-method-tag,
.about-page .ab-method-line.in-view .ab-method-title,
.about-page .ab-method-line.in-view .ab-method-desc {
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 0.6s ease calc(var(--d) + 240ms),
    transform 0.6s ease calc(var(--d) + 240ms);
}

/* 资料原则：单独一行 */
.about-page .ab-method-principles {
  margin-top: 56px;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  padding: 20px 28px;
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--about-border);
  border-left: 3px solid var(--about-gold);
  border-radius: 12px;
}
.about-page .ab-method-principles-lead {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--about-teal-dark);
  margin-right: 18px;
  white-space: nowrap;
}
.about-page .ab-method-principles-list {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  margin: 0;
  padding: 0;
}
.about-page .ab-method-principles-list li {
  padding: 0 18px;
  border-right: 1px solid var(--about-border);
}
.about-page .ab-method-principles-list li:last-child { border-right: none; }

/* ---- 平台愿景 + 结尾（about-vision） ---- */
/* 米白背景 + 浅水青局部区域 + 低透明度水波 */
.about-page .ab-vision-wrap {
  position: relative;
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 48px 44px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  background:
    radial-gradient(720px 300px at 50% 0%, rgba(23, 101, 95, 0.06) 0%, transparent 70%),
    linear-gradient(160deg, rgba(231, 241, 239, 0.55) 0%, rgba(242, 247, 245, 0.4) 100%);
  overflow: hidden;
}
/* 低透明度水波背景（纯装饰） */
.about-page .ab-vision-wrap::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(560px 90px at 12% 96%, rgba(23, 101, 95, 0.10) 0%, transparent 62%),
    radial-gradient(520px 70px at 88% 100%, rgba(198, 161, 91, 0.10) 0%, transparent 60%);
}
.about-page .ab-vision-wrap > * { position: relative; }
.about-page .ab-vision-wrap .ab-prose {
  max-width: 760px;
}

/* 结尾 CTA：普通文化入口样式 */
.about-page .ab-vision-cta {
  margin-top: 48px;
  text-align: center;
}
.about-page .ab-vision-cta-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 14px;
  margin-top: 24px;
}
.about-page .ab-vision-cta-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 3px;
  text-decoration: none;
  border-radius: 999px;
  padding: 13px 30px;
  transition: transform var(--motion-fast) var(--ease-out), box-shadow var(--motion-fast) var(--ease-out), background-color var(--motion-fast), color var(--motion-fast), border-color var(--motion-fast);
}
.about-page .ab-vision-cta-primary {
  background: var(--about-teal);
  border: 1px solid var(--about-teal);
  color: var(--about-paper);
}
.about-page .ab-vision-cta-primary:hover {
  background: var(--about-teal-dark);
  border-color: var(--about-teal-dark);
  transform: translateY(-2px);
  box-shadow: 0 10px 22px rgba(23, 101, 95, 0.24);
}
.about-page .ab-vision-cta-ghost {
  background: transparent;
  border: 1px solid var(--about-teal);
  color: var(--about-teal);
}
.about-page .ab-vision-cta-ghost:hover {
  background: rgba(23, 101, 95, 0.08);
  transform: translateY(-2px);
}

/* 赛题回应（about-theme）：两栏与引文滚动淡入 */
.about-page .ab-editorial-grid,
.about-page .ab-editorial .ab-theme-quote {
  opacity: 0;
  transform: translateY(16px);
}
.about-page .ab-editorial.in-view .ab-editorial-grid,
.about-page .ab-editorial.in-view .ab-theme-quote {
  opacity: 1;
  transform: none;
  transition:
    opacity 0.6s ease,
    transform 0.6s ease;
}

/* 愿景引文（about-vision）：引文淡入 + 金色水线从左展开 */
.about-page .ab-vision .ab-theme-quote {
  position: relative;
  overflow: hidden;
}
.about-page .ab-vision .ab-theme-quote::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--about-gold) 0%, rgba(198, 161, 91, 0.3) 100%);
  border-radius: 2px;
  transform: scaleX(0);
  transform-origin: left center;
}
.about-page .ab-vision .ab-theme-quote p {
  opacity: 0;
  transform: translateY(10px);
}
.about-page .ab-vision.in-view .ab-theme-quote::before {
  transform: scaleX(1);
  transition: transform 0.6s ease;
}
.about-page .ab-vision.in-view .ab-theme-quote p {
  opacity: 1;
  transform: none;
  transition:
    opacity 0.6s ease 0.12s,
    transform 0.6s ease 0.12s;
}

/* ---- 探索入口：三个文化入口 + 次级链接（about-explore） ---- */
.about-page .ab-explore {
  background:
    radial-gradient(760px 280px at 50% 0%, rgba(23, 101, 95, 0.05) 0%, transparent 70%),
    rgba(231, 241, 239, 0.5);
}
.about-page .ab-explore-rule {
  display: block;
  width: 46px;
  height: 2px;
  margin: 20px auto 0;
  background: var(--about-gold);
  border-radius: 2px;
}

.about-page .ab-explore-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.about-page .ab-explore-card {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 32px 28px 28px;
  background: rgba(255, 255, 255, 0.74);
  border: 1px solid var(--about-border);
  border-radius: var(--radius-md);
  text-decoration: none;
  overflow: hidden;
  transition: transform var(--motion-fast) var(--ease-out), box-shadow var(--motion-fast) var(--ease-out);
}
.about-page .ab-explore-card:hover,
.about-page .ab-explore.in-view .ab-explore-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--about-shadow);
}
.about-page .ab-explore-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--about-water-light);
  border: 1px solid var(--about-border);
  transition: border-color var(--motion-fast), color var(--motion-fast);
}
.about-page .ab-explore-card:hover .ab-explore-num {
  border-color: var(--about-gold);
  color: var(--about-gold);
}
.about-page .ab-explore-name {
  margin-top: 20px;
}
.about-page .ab-explore-subtitle {
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--about-gold);
  margin-top: 10px;
}
.about-page .ab-explore-subtitle::before {
  content: "";
  display: inline-block;
  width: 20px;
  height: 2px;
  border-radius: 2px;
  background: var(--about-gold);
  vertical-align: middle;
  margin-right: 10px;
}
.about-page .ab-explore-desc {
  margin-top: 12px;
  flex: 1;
}
.about-page .ab-explore-go {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 22px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 2px;
  color: var(--about-teal);
  padding-bottom: 2px;
  border-bottom: 1px solid var(--about-border);
}
.about-page .ab-explore-arrow {
  transition: transform var(--motion-fast);
}
.about-page .ab-explore-card:hover .ab-explore-go {
  color: var(--about-gold);
  border-color: var(--about-gold);
}
.about-page .ab-explore-card:hover .ab-explore-arrow,
.about-page .ab-explore-sub-link:hover .ab-explore-arrow {
  transform: translateX(4px);
}

/* 次级入口：普通文字链接 */
.about-page .ab-explore-sub {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px 44px;
  margin-top: 44px;
}
.about-page .ab-explore-sub-link {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  text-decoration: none;
  padding: 7px 0 8px;
  border-bottom: 1px solid var(--about-border);
}
.about-page .ab-explore-sub-name {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: 3px;
  color: var(--about-teal-dark);
  transition: color var(--motion-fast);
}
.about-page .ab-explore-sub-link:hover .ab-explore-sub-name {
  color: var(--about-gold);
  border-color: var(--about-gold);
}
.about-page .ab-explore-sub .ab-explore-arrow {
  align-self: center;
  color: var(--about-teal);
}

/* 入场：三入口与次级链接依次淡入上移 */
.about-page .ab-explore-card,
.about-page .ab-explore-sub-link {
  opacity: 0;
  transform: translateY(14px);
}
.about-page .ab-explore-card:nth-of-type(2),
.about-page .ab-explore-sub-link:nth-of-type(2) { --d: 140ms; }
.about-page .ab-explore-card:nth-of-type(3) { --d: 280ms; }
.about-page .ab-explore.in-view .ab-explore-card,
.about-page .ab-explore.in-view .ab-explore-sub-link {
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 0.6s ease calc(var(--d, 0) + 200ms),
    transform 0.6s ease calc(var(--d, 0) + 200ms);
}
.about-page .ab-explore.in-view .ab-explore-card:hover,
.about-page .ab-explore.in-view .ab-explore-sub-link:hover {
  transition: transform var(--motion-fast) var(--ease-out), box-shadow var(--motion-fast) var(--ease-out);
}

/* 页脚链接：本页扩大点击区域至不小于 44px（仅作用于本页） */
.about-page .footer-col a { padding: 11px 0; }

/* ---- 响应式 ---- */
@media (max-width: 1024px) {
  .about-page .ab-value-grid { grid-template-columns: repeat(2, 1fr); }
  .about-page .ab-sample-map-list { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 900px) {
  .about-page .ab-hero-inner {
    grid-template-columns: 1fr;
    gap: 44px;
  }
  .about-page .ab-hero-copy {
    justify-self: center;
    text-align: center;
  }
  .about-page .ab-hero-kicker { justify-content: center; }
  .about-page .ab-hero-desc { max-width: 560px; margin-inline: auto; }
  .about-page .ab-hero-actions { justify-content: center; }
  .about-page .ab-hero-figure {
    justify-self: center;
    max-width: 560px;
  }
  .about-page .ab-editorial-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .about-page .ab-editorial-head {
    text-align: center;
  }
  .about-page .ab-theme-quote { margin-top: 40px; }

  /* 核心命题：移动端改为纵向时间轴 */
  .about-page .ab-flow {
    grid-template-columns: 1fr;
    gap: 0;
    padding-top: 0;
  }
  .about-page .ab-flow-item {
    display: grid;
    grid-template-columns: 56px 1fr;
    gap: 20px;
    align-items: start;
    padding-bottom: 44px;
  }
  .about-page .ab-flow-item:last-child { padding-bottom: 0; }
  .about-page .ab-flow-num { margin-top: 4px; }
  .about-page .ab-flow-track {
    top: 0;
    bottom: 0;
    left: 28px;
    right: auto;
    width: 2px;
    height: auto;
    transform: none;
  }
  .about-page .ab-flow-track-fill {
    background: linear-gradient(180deg, rgba(23, 101, 95, 0.65), rgba(23, 101, 95, 0.32));
    background-size: 100% 0%;
    background-position: top center;
  }
  .about-page .ab-flow.in-view .ab-flow-track-fill { background-size: 100% 100%; }
  .about-page .ab-flow-track-flow {
    background: linear-gradient(180deg, transparent 0%, rgba(198, 161, 91, 0.55) 50%, transparent 100%);
    background-size: 100% 50%;
    background-position: 0 -100%;
  }
  .about-page .ab-flow:hover .ab-flow-track-flow {
    animation: abFlowSweepV 16s linear infinite;
  }
  @keyframes abFlowSweepV {
    from { background-position: 0 -100%; }
    to { background-position: 0 100%; }
  }

  /* 数字文化路径：横向卡片降列，隐藏横向水线 */
  .about-page .ab-path {
    grid-template-columns: repeat(3, 1fr);
  }
  .about-page .ab-path-rail { display: none; }

  /* 地方样本：扩散水脉简化为网格节点 */
  .about-page .ab-delta-map {
    height: auto;
    padding-top: 26px;
  }
  .about-page .ab-delta-svg { display: none; }
  .about-page .ab-delta-nodes {
    position: static;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px 12px;
  }
  .about-page .ab-delta-dot { display: none; }
  .about-page .ab-delta-title { min-height: auto; }

  /* 表达方法：单列纵向水流线 */
  .about-page .ab-method-line {
    grid-template-columns: 1fr;
    gap: 0;
    padding-top: 0;
  }
  .about-page .ab-method-item {
    display: grid;
    grid-template-columns: 52px 1fr;
    gap: 20px;
    align-items: start;
    text-align: left;
    padding-bottom: 40px;
  }
  .about-page .ab-method-item:last-child { padding-bottom: 0; }
  .about-page .ab-method-num { margin-top: 4px; }
  .about-page .ab-method-track {
    top: 0;
    bottom: 0;
    left: 25px;
    right: auto;
    width: 2px;
    height: auto;
    transform: none;
  }
  .about-page .ab-method-track-fill {
    background: linear-gradient(180deg, rgba(23, 101, 95, 0.6), rgba(23, 101, 95, 0.3));
    background-size: 100% 0%;
    background-position: top center;
  }
  .about-page .ab-method-line.in-view .ab-method-track-fill { background-size: 100% 100%; }
  .about-page .ab-method-tag { margin-top: 0; }
  .about-page .ab-method-title { margin: 8px 0 8px; }
  .about-page .ab-method-principles {
    margin-top: 40px;
    padding: 18px 20px;
  }

  /* 探索入口：移动端单列 */
  .about-page .ab-explore-cards { grid-template-columns: 1fr; }
  .about-page .ab-explore-sub {
    flex-direction: column;
    align-items: center;
    gap: 16px;
    margin-top: 36px;
  }
}

@media (max-width: 768px) {
  .about-page .ab-section { padding: 48px 0; }
  .about-page .ab-value-grid { grid-template-columns: 1fr; }
  .about-page .ab-sample-map { padding: 20px 16px; }
  .about-page .ab-sample-map-list { grid-template-columns: 1fr; }
  .about-page .ab-sec-head { margin-bottom: 32px; }
  .about-page .ab-vision-wrap { padding: 32px 20px 36px; }
  .about-page .ab-theme-quote { padding: 26px 24px; }
  .about-page .ab-vision-cta-actions { flex-direction: column; align-items: stretch; }
  .about-page .ab-vision-cta-btn { width: 100%; }
  .about-page .ab-method-principles-list li {
    padding: 0 0 0 14px;
    border-right: none;
    margin-right: 14px;
  }
  /* 数字文化路径：两列 */
  .about-page .ab-path { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 520px) {
  /* 数字文化路径：单列 */
  .about-page .ab-path { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  .about-page .ab-vision-cta-btn,
  .about-page .ab-explore-card,
  .about-page .ab-explore-sub-link { transition: none; }
  .about-page .ab-vision-cta-btn:hover,
  .about-page .ab-explore-card:hover,
  .about-page .ab-explore.in-view .ab-explore-card:hover { transform: none; }
  .about-page .ab-hero-kicker,
  .about-page .ab-hero-line-1,
  .about-page .ab-hero-line-2,
  .about-page .ab-hero-sub,
  .about-page .ab-hero-desc,
  .about-page .ab-hero-actions,
  .about-page .ab-hero-figure,
  .about-page .ab-hero-ripple {
    animation: none;
    opacity: 1;
    transform: none;
  }
  /* 核心命题：关闭绘制/流动/入场动画 */
  .about-page .ab-flow-track-fill,
  .about-page .ab-flow-track-flow {
    transition: none;
    animation: none;
  }
  .about-page .ab-flow-track-fill { background-size: 100% 100%; }
  .about-page .ab-flow-track-flow { opacity: 0; }
  .about-page .ab-flow:hover .ab-flow-track-flow,
  .about-page .ab-path:hover .ab-path-rail-flow {
    animation: none;
    opacity: 0;
  }
  .about-page .ab-flow-num,
  .about-page .ab-flow-cat,
  .about-page .ab-flow-title,
  .about-page .ab-flow-desc {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .about-page .ab-flow-item:hover .ab-flow-num { transform: none; }
  /* 数字文化路径：关闭绘制/流动/入场动画 */
  .about-page .ab-path-rail-fill,
  .about-page .ab-path-rail-flow {
    transition: none;
    animation: none;
  }
  .about-page .ab-path-rail-fill { background-size: 100% 100%; }
  .about-page .ab-path-rail-flow { opacity: 0; }
  .about-page .ab-path-node,
  .about-page .ab-path-title,
  .about-page .ab-path-pos,
  .about-page .ab-path-desc,
  .about-page .ab-path-link,
  .about-page .ab-path-side {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .about-page .ab-path-card:hover .ab-path-node { transform: none; }
  /* 地方样本：扩散水流线直接画完，节点全显 */
  .about-page .ab-delta-line {
    transition: none;
    stroke-dashoffset: 0;
  }
  .about-page .ab-delta-node {
    opacity: 1;
    transform: none;
    transition: none;
  }
  /* 表达方法：水线画完、编号常亮、内容全显 */
  .about-page .ab-method-track-fill {
    transition: none;
    background-size: 100% 100%;
  }
  .about-page .ab-method-num {
    opacity: 1;
    transform: none;
    transition: none;
    background: var(--about-teal);
    border-color: var(--about-teal);
    color: var(--about-paper);
  }
  .about-page .ab-method-tag,
  .about-page .ab-method-title,
  .about-page .ab-method-desc {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .about-page .ab-method-item:hover .ab-method-num { transform: none; }
  /* 探索入口：内容全显，无上移动效 */
  .about-page .ab-explore-card,
  .about-page .ab-explore-sub-link {
    opacity: 1;
    transform: none;
    transition: none;
  }
  /* 赛题回应 / 愿景引文：内容全显，金线展开完毕 */
  .about-page .ab-editorial-grid,
  .about-page .ab-editorial .ab-theme-quote,
  .about-page .ab-vision .ab-theme-quote::before,
  .about-page .ab-vision .ab-theme-quote p {
    opacity: 1;
    transform: none;
    transition: none;
  }
}