/* ===== 品牌理念页 · page-about ===== */

.page-about {
  --ab-measure: 46rem;
  --ab-measure-wide: 62rem;
  --ab-gap: clamp(20px, 4vw, 40px);
}

.page-about .about-crumbs {
  padding-top: clamp(16px, 3vw, 26px);
  padding-bottom: 6px;
}

/* ---------- 封面 ---------- */

.page-about .about-cover {
  position: relative;
  padding: clamp(20px, 4vw, 40px) 0 clamp(32px, 6vw, 60px);
  background:
    radial-gradient(120% 88% at 8% 0%, rgba(53, 224, 212, .13), transparent 60%),
    linear-gradient(180deg, var(--mid) 0%, var(--ink) 74%);
  border-bottom: 1px solid var(--line);
}

.page-about .about-cover-inner {
  max-width: 980px;
}

.page-about .about-h1 {
  margin: 18px 0 0;
  max-width: 640px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(34px, 8vw, 62px);
  line-height: 1.08;
  letter-spacing: -0.015em;
  color: var(--paper);
}

.page-about .about-lead {
  margin: 22px 0 0;
  max-width: 640px;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--paper);
}

.page-about .cover-index {
  list-style: none;
  margin: 36px 0 0;
  padding: 24px 0 0;
  border-top: 1px solid var(--line);
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

.page-about .cover-item {
  display: grid;
  gap: 6px;
}

.page-about .cover-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 22px;
  line-height: 1.1;
  color: var(--lime);
  letter-spacing: -0.02em;
}

.page-about .cover-lbl {
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

@media (min-width: 720px) {
  .page-about .cover-index {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 28px;
  }
  .page-about .cover-num {
    font-size: 26px;
  }
}

/* ---------- 主体布局 ---------- */

.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--ab-gap);
  padding-top: clamp(32px, 6vw, 64px);
  padding-bottom: clamp(48px, 9vw, 96px);
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: 172px minmax(0, 1fr);
    column-gap: clamp(40px, 6vw, 76px);
  }
}

/* ---------- 章节索引 ---------- */

.page-about .about-index {
  min-width: 0;
}

@media (min-width: 1024px) {
  .page-about .about-index {
    position: sticky;
    top: 116px;
    align-self: start;
  }
}

.page-about .ix-list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0 0 6px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .ix-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  color: var(--muted);
  font-size: 13px;
  white-space: nowrap;
  text-decoration: none;
  transition: color .16s var(--ease), border-color .16s var(--ease), background-color .16s var(--ease);
}

.page-about .ix-link:hover,
.page-about .ix-link:focus-visible {
  color: var(--cyan);
  border-color: var(--cyan);
}

.page-about .ix-num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--cyan);
}

@media (min-width: 1024px) {
  .page-about .ix-list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding: 0;
  }
  .page-about .ix-link {
    width: 100%;
    padding: 10px 12px;
    border-color: transparent;
    border-radius: 12px;
  }
  .page-about .ix-link:hover,
  .page-about .ix-link:focus-visible {
    background: rgba(53, 224, 212, .07);
  }
}

/* ---------- 章节通用 ---------- */

.page-about .about-flow {
  min-width: 0;
}

.page-about .about-sec {
  padding: 0;
}

.page-about .about-sec + .about-rule {
  margin: clamp(36px, 7vw, 64px) 0 clamp(32px, 6vw, 56px);
}

.page-about .about-rule {
  position: relative;
  height: 1px;
  background: var(--line);
}

.page-about .about-rule::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  height: 1px;
  background: var(--cyan);
  width: 20%;
}

.page-about .about-rule[data-weight="2"]::before { width: 38%; }
.page-about .about-rule[data-weight="3"]::before { width: 64%; }
.page-about .about-rule[data-weight="4"]::before { width: 100%; }

.page-about .sec-index {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--cyan);
}

.page-about .sec-title {
  margin: 0 0 24px;
  max-width: 520px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(24px, 5vw, 38px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--paper);
}

.page-about .sec-p {
  margin: 0 0 18px;
  max-width: var(--ab-measure);
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--paper);
}

.page-about .sec-p--wide {
  max-width: var(--ab-measure-wide);
}

.page-about .sec-note {
  margin: 30px 0 0;
  padding-left: 18px;
  max-width: 30rem;
  border-left: 2px solid var(--cyan);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(18px, 3.4vw, 23px);
  line-height: 1.5;
  color: var(--paper);
}

/* ---------- 版本迭代 ---------- */

.page-about .ver-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}

@media (min-width: 1024px) {
  .page-about .ver-grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    column-gap: clamp(36px, 5vw, 56px);
    align-items: start;
  }
}

.page-about .ver-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .ver-item {
  display: grid;
  grid-template-columns: 68px minmax(0, 1fr);
  column-gap: 16px;
  row-gap: 8px;
  padding: 22px 12px 22px 0;
  border-top: 1px solid var(--line);
  border-radius: 0 var(--r-md) var(--r-md) 0;
  transition: border-color .18s var(--ease), background-color .18s var(--ease);
}

.page-about .ver-item:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .ver-item:hover,
.page-about .ver-item:focus-within {
  border-top-color: var(--cyan);
  background-color: rgba(53, 224, 212, .05);
}

.page-about .ver-tag {
  grid-column: 1;
  justify-self: start;
  align-self: start;
  padding: 3px 8px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 12px;
  color: var(--cyan);
  transition: color .18s var(--ease), background-color .18s var(--ease), border-color .18s var(--ease);
}

.page-about .ver-item:hover .ver-tag,
.page-about .ver-item:focus-within .ver-tag {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink-on-cyan);
}

.page-about .ver-title {
  grid-column: 2;
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 18px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .ver-copy {
  grid-column: 2;
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--paper);
}

.page-about .ver-more {
  grid-column: 2;
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
  transition: color .18s var(--ease);
}

.page-about .ver-item:hover .ver-more {
  color: var(--ice);
}

.page-about .ver-figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--charcoal);
}

.page-about .ver-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 12 / 7;
  object-fit: cover;
}

.page-about .ver-figure .media-caption,
.page-about .about-figure-wide .media-caption {
  padding: 12px 16px 14px;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 数据来源 ---------- */

.page-about .about-figure-wide {
  margin: 4px 0 32px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--charcoal);
}

.page-about .about-figure-wide img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

.page-about .day-list {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  max-width: var(--ab-measure);
}

.page-about .day-list li {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  column-gap: 16px;
  align-items: baseline;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
  line-height: 1.8;
  color: var(--paper);
}

.page-about .day-list li:first-child {
  border-top: 1px solid var(--line);
}

.page-about .day-t {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 15px;
  color: var(--cyan);
}

.page-about .day-tail {
  margin-top: 26px;
}

/* ---------- 覆盖范围 ---------- */

.page-about .cov-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

@media (min-width: 900px) {
  .page-about .cov-grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    column-gap: clamp(32px, 5vw, 56px);
    align-items: start;
  }
}

.page-about .cov-figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--charcoal);
}

.page-about .cov-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 5;
  object-fit: cover;
}

.page-about .cov-nums {
  margin-top: 36px;
  padding-top: 30px;
  border-top: 1px solid var(--line);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px 20px;
}

@media (min-width: 760px) {
  .page-about .cov-nums {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 34px 28px;
  }
}

.page-about .cov-item {
  display: grid;
  gap: 6px;
  animation: about-num-in .55s var(--ease) both;
}

.page-about .cov-nums .cov-item:nth-child(1) { animation-delay: .05s; }
.page-about .cov-nums .cov-item:nth-child(2) { animation-delay: .10s; }
.page-about .cov-nums .cov-item:nth-child(3) { animation-delay: .15s; }
.page-about .cov-nums .cov-item:nth-child(4) { animation-delay: .20s; }
.page-about .cov-nums .cov-item:nth-child(5) { animation-delay: .25s; }
.page-about .cov-nums .cov-item:nth-child(6) { animation-delay: .30s; }

@keyframes about-num-in {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}

.page-about .cov-num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(30px, 7vw, 40px);
  line-height: 1.05;
  letter-spacing: -0.03em;
  color: var(--lime);
}

.page-about .cov-lbl {
  font-size: 13px;
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 结尾入口 ---------- */

.page-about .about-cta {
  margin-top: 34px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .cov-item {
    animation: none;
    opacity: 1;
    transform: none;
  }
  .page-about .ix-link,
  .page-about .ver-item,
  .page-about .ver-tag,
  .page-about .ver-more {
    transition: none;
  }
}