.page-about {
  --about-radius: 2px;
  --about-rule: rgba(18, 58, 76, 0.22);
  --about-rule-soft: rgba(18, 58, 76, 0.12);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(26px, 5vw, 54px) 0 clamp(26px, 5vw, 48px);
  background: linear-gradient(180deg, var(--paper) 0%, var(--mist) 100%);
  border-bottom: 1px solid var(--about-rule-soft);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-radial-gradient(circle at 86% 12%,
      transparent 0 40px,
      rgba(30, 111, 140, 0.10) 40px 41px,
      transparent 41px 82px,
      rgba(30, 111, 140, 0.07) 82px 83px);
}

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

.page-about .about-h1 {
  margin: 12px 0 0;
  max-width: 620px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(30px, 6vw, 52px);
  line-height: 1.16;
  letter-spacing: 0.01em;
  color: var(--lake-deep);
}

.page-about .about-lede {
  margin: 18px 0 0;
  max-width: 46em;
  font-size: clamp(16px, 1.7vw, 18px);
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule-soft);
}

.page-about .about-stats li {
  background: var(--paper);
  padding: 13px 15px 14px;
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(19px, 2.4vw, 23px);
  letter-spacing: 0.04em;
  color: var(--apricot-deep);
  line-height: 1.2;
}

.page-about .stat-label {
  display: block;
  margin-top: 3px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--rock);
}

/* ---------- 开篇图 ---------- */

.page-about .about-hero-figure {
  margin: 0;
  padding: clamp(22px, 4vw, 40px) 0 0;
  background: var(--mist);
}

.page-about .about-cap {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  line-height: 1.6;
  color: var(--rock);
}

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

/* ---------- 章节通用 ---------- */

.page-about .about-section {
  padding-top: clamp(46px, 7vw, 78px);
  padding-bottom: clamp(46px, 7vw, 78px);
}

.page-about .about-figure {
  margin: clamp(28px, 4vw, 44px) 0 0;
}

/* ---------- 角色卡 ---------- */

.page-about .role-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px 22px;
  margin-top: 8px;
}

.page-about .role-card {
  position: relative;
  background: var(--paper);
  border: 1px solid var(--about-rule);
  border-radius: var(--about-radius);
  padding: 26px 20px 20px;
  box-shadow: var(--shadow-card);
  transition: box-shadow 240ms var(--ease), transform 240ms var(--ease);
}

.page-about .role-card::after {
  content: "";
  position: absolute;
  right: -1px;
  bottom: -1px;
  width: 38px;
  height: 15px;
  background: var(--mist);
  border: 1px solid var(--about-rule);
  border-bottom: 0;
  border-right: 0;
}

.page-about .role-card:hover,
.page-about .role-card:focus-within {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lift);
}

.page-about .role-tag {
  position: absolute;
  top: -11px;
  left: 14px;
  padding: 3px 10px;
  background: var(--amber);
  color: var(--lake-deep);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  transform: rotate(-1.5deg);
}

.page-about .role-name {
  margin: 0;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--lake-deep);
}

.page-about .role-text {
  margin: 10px 0 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--ink);
}

.page-about .role-more {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--about-rule-soft);
}

.page-about .role-more summary {
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--lake);
  list-style: none;
}

.page-about .role-more summary::-webkit-details-marker {
  display: none;
}

.page-about .role-more summary::before {
  content: "+ ";
  color: var(--apricot);
}

.page-about .role-more[open] summary::before {
  content: "− ";
}

.page-about .role-more p {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--rock);
}

/* ---------- 评审步骤 ---------- */

.page-about .steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin: 8px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .step {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 17px 18px 18px;
  background: var(--paper);
  border: 1px solid var(--about-rule-soft);
  border-left: 3px solid var(--apricot);
  border-radius: var(--about-radius);
  transition: border-left-color 200ms var(--ease), transform 240ms var(--ease);
}

.page-about .step:hover {
  border-left-color: var(--lake);
  transform: translateX(3px);
}

.page-about .step-num {
  font-family: var(--font-mono);
  font-size: 22px;
  letter-spacing: 0.05em;
  line-height: 1.25;
  color: var(--apricot);
}

.page-about .step-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--lake-deep);
}

.page-about .step-text {
  margin: 7px 0 0;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--ink);
}

/* ---------- 更新节奏 ---------- */

.page-about .rhythm {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
  margin-top: 8px;
}

.page-about .rhythm-card {
  position: relative;
  padding: 20px 20px 22px;
  background: var(--paper);
  border: 1px solid var(--about-rule);
  border-radius: var(--about-radius);
  box-shadow: var(--shadow-card);
}

.page-about .rhythm-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: linear-gradient(180deg, var(--apricot) 0%, var(--amber) 100%);
}

.page-about .rhythm-when {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.1em;
  color: var(--lake);
}

.page-about .rhythm-title {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--lake-deep);
}

.page-about .rhythm-text {
  margin: 8px 0 0;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .topic-meter {
  margin-top: 28px;
  padding: 20px 20px 18px;
  background: var(--mist);
  border: 1px solid var(--about-rule-soft);
  border-radius: var(--about-radius);
}

.page-about .topic-meter-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
}

.page-about .topic-meter-label {
  font-size: 15.5px;
  line-height: 1.6;
  color: var(--ink);
}

.page-about .topic-meter-value {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--apricot-deep);
}

.page-about .meter {
  position: relative;
  height: 10px;
  margin-top: 12px;
  background: var(--paper);
  border: 1px solid var(--about-rule-soft);
  overflow: hidden;
}

.page-about .meter-fill {
  display: block;
  height: 100%;
  width: 33.3%;
  background: linear-gradient(90deg, var(--apricot) 0%, var(--amber) 100%);
  animation: about-meter 900ms var(--ease) both;
}

@keyframes about-meter {
  from { width: 0; }
  to { width: 33.3%; }
}

.page-about .topic-meter-note {
  margin: 12px 0 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--rock);
}

.page-about .about-link {
  color: var(--lake);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.page-about .about-link:hover {
  color: var(--apricot-deep);
}

/* ---------- 时间轴 ---------- */

.page-about .tl-list {
  position: relative;
  margin: 10px 0 0;
  padding: 0 0 0 56px;
  list-style: none;
}

.page-about .tl-list::before {
  content: "";
  position: absolute;
  left: 20px;
  top: 12px;
  bottom: 34px;
  width: 1px;
  background: repeating-linear-gradient(
    to bottom,
    rgba(30, 111, 140, 0.55) 0 5px,
    transparent 5px 12px
  );
}

.page-about .tl-item {
  position: relative;
  padding-bottom: 34px;
}

.page-about .tl-item:last-child {
  padding-bottom: 0;
}

.page-about .tl-dot {
  position: absolute;
  left: -47px;
  top: 4px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--rock);
  transition: border-color 240ms var(--ease), transform 240ms var(--ease);
}

.page-about .tl-dot--filled {
  border-color: var(--apricot);
  background: var(--apricot);
  box-shadow: inset 0 0 0 5px var(--paper);
}

.page-about .tl-dot--now {
  border-color: var(--lake);
  background: var(--lake);
  box-shadow: inset 0 0 0 5px var(--paper), 0 0 0 5px rgba(30, 111, 140, 0.14);
}

.page-about .tl-item:hover .tl-dot {
  transform: scale(1.12);
}

.page-about .tl-year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--apricot-deep);
}

.page-about .tl-title {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--lake-deep);
}

.page-about .tl-text {
  margin: 8px 0 0;
  max-width: 52em;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--ink);
}

.page-about .tl-item--now .tl-year {
  color: var(--lake);
}

/* ---------- 资料对齐 ---------- */

.page-about .align-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: 10px;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule-soft);
}

.page-about .align-item {
  padding: 20px 18px 21px;
  background: var(--paper);
}

.page-about .align-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 17.5px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--lake-deep);
}

.page-about .align-text {
  margin: 9px 0 0;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .align-tail {
  margin: 22px 0 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--rock);
}

/* ---------- 下一步 ---------- */

.page-about .about-next {
  background: var(--lake-deep);
  color: var(--paper);
}

.page-about .about-next .chapter-title {
  color: var(--paper);
}

.page-about .about-next .chapter-num {
  color: var(--amber);
}

.page-about .about-next .section-note {
  color: rgba(251, 249, 246, 0.72);
}

.page-about .next-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 10px;
}

.page-about .next-card {
  position: relative;
  display: block;
  padding: 18px 44px 19px 18px;
  background: rgba(251, 249, 246, 0.06);
  border: 1px solid rgba(251, 249, 246, 0.24);
  border-radius: var(--about-radius);
  text-decoration: none;
  transition: background 200ms var(--ease), border-color 200ms var(--ease), transform 240ms var(--ease);
}

.page-about .next-card:hover,
.page-about .next-card:focus-visible {
  background: rgba(240, 138, 60, 0.16);
  border-color: var(--apricot);
  transform: translateY(-2px);
}

.page-about .next-kicker {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--amber);
}

.page-about .next-title {
  display: block;
  margin-top: 7px;
  font-size: 16px;
  line-height: 1.65;
  color: var(--paper);
}

.page-about .next-arrow {
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--apricot);
}

.page-about .next-note {
  margin: 24px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(251, 249, 246, 0.75);
}

.page-about .about-link--light {
  color: var(--amber);
}

.page-about .about-link--light:hover {
  color: var(--paper);
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 900px) {
  .page-about .role-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

  .page-about .step {
    grid-template-columns: 64px minmax(0, 1fr);
    padding: 20px 24px 21px;
  }

  .page-about .topic-meter {
    padding: 24px 26px 22px;
  }

  .page-about .role-card {
    padding: 28px 24px 22px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-lede {
    margin-top: 22px;
  }

  .page-about .tl-list {
    padding-left: 78px;
  }

  .page-about .tl-list::before {
    left: 26px;
  }

  .page-about .tl-dot {
    left: -64px;
    width: 26px;
    height: 26px;
  }

  .page-about .tl-dot--filled {
    box-shadow: inset 0 0 0 6px var(--paper);
  }

  .page-about .tl-dot--now {
    box-shadow: inset 0 0 0 6px var(--paper), 0 0 0 6px rgba(30, 111, 140, 0.14);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .meter-fill {
    animation: none;
    width: 33.3%;
  }

  .page-about .role-card,
  .page-about .step,
  .page-about .next-card,
  .page-about .tl-dot {
    transition: none;
  }
}