.page-disclaimer {
  --usage-line: rgba(107, 106, 100, 0.24);
  --usage-line-soft: rgba(107, 106, 100, 0.14);
  --usage-rail-w: 208px;
  --usage-measure: 66ch;
  display: block;
}

/* ---------- 首屏 ---------- */
.page-disclaimer .usage-hero {
  position: relative;
  isolation: isolate;
  padding-block: clamp(26px, 5vw, 58px) clamp(30px, 5vw, 62px);
  border-bottom: 1px solid var(--usage-line);
  background: linear-gradient(180deg, rgba(223, 205, 169, 0.38), rgba(245, 239, 227, 0) 78%);
  overflow: hidden;
}

.page-disclaimer .usage-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image: linear-gradient(to right, var(--usage-line-soft) 1px, transparent 1px);
  background-size: 56px 100%;
  -webkit-mask-image: linear-gradient(180deg, #000 0%, transparent 92%);
  mask-image: linear-gradient(180deg, #000 0%, transparent 92%);
  pointer-events: none;
}

.page-disclaimer .usage-hero-inner {
  display: grid;
  gap: clamp(22px, 4vw, 46px);
  align-items: center;
}

.page-disclaimer .usage-hero-copy .breadcrumbs {
  margin-bottom: 18px;
}

.page-disclaimer .usage-kicker {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--teal);
}

.page-disclaimer .usage-title {
  margin: 0 0 18px;
  font-size: clamp(30px, 5.2vw, 46px);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-disclaimer .usage-lead {
  max-width: 62ch;
  margin: 0 0 22px;
  font-size: 16px;
  line-height: 1.9;
  color: var(--rock);
}

.page-disclaimer .usage-meta {
  display: inline-block;
  margin: 0;
  padding: 8px 16px;
  border-radius: var(--pill);
  border: 1px solid var(--usage-line);
  background: rgba(255, 255, 255, 0.55);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock);
}

.page-disclaimer .usage-hero-media {
  margin: 0;
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.page-disclaimer .usage-hero-media img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

/* ---------- 主体布局 ---------- */
.page-disclaimer .usage-layout {
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  padding-block: clamp(34px, 6vw, 72px);
}

/* ---------- 索引导轨 ---------- */
.page-disclaimer .usage-rail {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 8px;
  scrollbar-width: thin;
}

.page-disclaimer .usage-rail::-webkit-scrollbar {
  height: 4px;
}

.page-disclaimer .usage-rail::-webkit-scrollbar-thumb {
  background: var(--rock);
  border-radius: 999px;
}

.page-disclaimer .usage-rail .rail-link {
  flex: 0 0 auto;
  padding: 9px 16px;
  border-radius: var(--pill);
  border: 1px solid var(--usage-line);
  background: rgba(255, 255, 255, 0.55);
  color: var(--rock);
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-disclaimer .usage-rail .rail-link:hover,
.page-disclaimer .usage-rail .rail-link:focus-visible {
  border-color: var(--cyan);
  color: var(--ink);
  background: rgba(0, 200, 206, 0.12);
}

.page-disclaimer .usage-main {
  min-width: 0;
}

/* ---------- 章节 ---------- */
.page-disclaimer .usage-section {
  padding-block: clamp(26px, 4vw, 42px);
  border-bottom: 1px solid var(--usage-line);
  scroll-margin-top: 104px;
}

.page-disclaimer .usage-section:first-child {
  padding-top: 0;
}

.page-disclaimer .usage-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  margin-bottom: 18px;
}

.page-disclaimer .usage-head .usage-kicker {
  margin-bottom: 6px;
}

.page-disclaimer .usage-num {
  padding-top: 4px;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--rust);
}

.page-disclaimer .usage-h2 {
  margin: 0;
  font-size: clamp(21px, 2.6vw, 28px);
  font-weight: 700;
  line-height: 1.35;
  color: var(--ink);
}

/* ---------- 条文列表 ---------- */
.page-disclaimer .clause-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--usage-line-soft);
}

.page-disclaimer .clause-item {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 10px;
  padding-block: 15px;
  border-bottom: 1px solid var(--usage-line-soft);
}

.page-disclaimer .clause-num {
  padding-top: 5px;
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--rust);
}

.page-disclaimer .clause-text {
  margin: 0;
  max-width: var(--usage-measure);
  font-size: 16px;
  line-height: 1.95;
  color: var(--ink);
}

.page-disclaimer .clause-text a {
  color: var(--teal);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color var(--dur) var(--ease);
}

.page-disclaimer .clause-text a:hover,
.page-disclaimer .clause-text a:focus-visible {
  color: var(--rust-deep);
}

/* ---------- 重点提示 ---------- */
.page-disclaimer .usage-highlight {
  margin: 22px 0 0;
  padding: clamp(18px, 3vw, 26px);
  border-radius: var(--radius-md);
  border: 1px solid rgba(4, 107, 112, 0.2);
  background: linear-gradient(135deg, rgba(223, 205, 169, 0.72), rgba(245, 239, 227, 0.95));
}

.page-disclaimer .usage-highlight-title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 700;
  color: var(--teal);
}

.page-disclaimer .usage-highlight p {
  margin: 0;
  max-width: var(--usage-measure);
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--ink);
}

.page-disclaimer .usage-highlight p + p {
  margin-top: 8px;
}

/* ---------- 折叠条目 ---------- */
.page-disclaimer .usage-matrix {
  margin-top: 20px;
}

.page-disclaimer .usage-matrix .matrix-item {
  border-bottom: 1px solid var(--usage-line-soft);
}

.page-disclaimer .usage-matrix .matrix-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-block: 14px;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}

.page-disclaimer .usage-matrix .matrix-summary::-webkit-details-marker {
  display: none;
}

.page-disclaimer .usage-matrix .matrix-summary::marker {
  content: "";
}

.page-disclaimer .usage-matrix .matrix-summary::after {
  content: "+";
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--teal);
}

.page-disclaimer .usage-matrix .matrix-item[open] .matrix-summary::after {
  content: "\2212";
}

.page-disclaimer .usage-matrix .matrix-body {
  padding-bottom: 16px;
}

.page-disclaimer .clause-sub {
  margin: 0;
  padding-left: 1.15em;
  max-width: var(--usage-measure);
  font-size: 15px;
  line-height: 1.9;
  color: var(--rock);
}

.page-disclaimer .clause-sub li {
  margin-block: 6px;
}

/* ---------- 回到开头 ---------- */
.page-disclaimer .usage-backtop {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 26px;
  padding: 10px 20px;
  border-radius: var(--pill);
  border: 1px solid var(--rock);
  background: rgba(255, 255, 255, 0.6);
  color: var(--ink);
  font-size: 14px;
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-disclaimer .usage-backtop:hover,
.page-disclaimer .usage-backtop:focus-visible {
  border-color: var(--cyan);
  background: rgba(0, 200, 206, 0.14);
  transform: translateY(-2px);
}

/* ---------- 收尾 ---------- */
.page-disclaimer .usage-next {
  padding-block: clamp(18px, 3vw, 34px) clamp(44px, 7vw, 84px);
}

/* ---------- 断点 ---------- */
@media (min-width: 720px) {
  .page-disclaimer .clause-item {
    grid-template-columns: 52px minmax(0, 1fr);
    gap: 18px;
    padding-block: 17px;
  }

  .page-disclaimer .clause-text {
    font-size: 17px;
  }

  .page-disclaimer .usage-num {
    font-size: 36px;
  }
}

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

  .page-disclaimer .usage-lead {
    font-size: 17px;
  }

  .page-disclaimer .usage-hero-media {
    aspect-ratio: 16 / 7;
  }
}

@media (min-width: 1024px) {
  .page-disclaimer .usage-layout {
    grid-template-columns: var(--usage-rail-w) minmax(0, 1fr);
    align-items: start;
  }

  .page-disclaimer .usage-rail {
    position: sticky;
    top: 104px;
    flex-direction: column;
    gap: 4px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-disclaimer .usage-rail .rail-link {
    padding: 10px 14px;
    border: 0;
    border-left: 2px solid var(--usage-line);
    border-radius: 0 var(--pill) var(--pill) 0;
    background: transparent;
  }

  .page-disclaimer .usage-rail .rail-link:hover,
  .page-disclaimer .usage-rail .rail-link:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(0, 200, 206, 0.1);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-disclaimer .usage-backtop,
  .page-disclaimer .usage-rail .rail-link {
    transition-duration: 120ms;
    transition-property: opacity, background-color, border-color, color;
  }

  .page-disclaimer .usage-backtop:hover,
  .page-disclaimer .usage-backtop:focus-visible {
    transform: none;
  }
}