.page-disclaimer {
  --usage-gap: clamp(28px, 5vw, 72px);
  --usage-fb-muted: #6B6058;
  padding-top: clamp(20px, 3vw, 40px);
}

.page-disclaimer .breadcrumb {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--dim);
  margin-bottom: clamp(20px, 3vw, 34px);
}

.page-disclaimer .breadcrumb a {
  color: var(--ash);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-disclaimer .breadcrumb a:hover,
.page-disclaimer .breadcrumb a:focus-visible {
  color: var(--ember);
  border-bottom-color: var(--ember);
}

.page-disclaimer .breadcrumb .breadcrumb__sep {
  margin: 0 8px;
  color: var(--line);
}

/* ---------- 首屏 ---------- */

.page-disclaimer .usage-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 28px);
  border-top: 1px solid var(--line);
  padding-top: clamp(18px, 3vw, 30px);
}

.page-disclaimer .usage-hero__title {
  font-size: clamp(52px, 13vw, 124px);
  font-weight: 900;
  line-height: 0.86;
  letter-spacing: -0.035em;
  margin: 10px 0 0;
  color: var(--paper);
}

.page-disclaimer .usage-hero__intro {
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.78;
  color: var(--ash);
  max-width: 54ch;
  margin: 0;
}

.page-disclaimer .usage-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-disclaimer .usage-hero__figure {
  margin: clamp(26px, 4vw, 46px) 0 0;
  position: relative;
}

.page-disclaimer .usage-hero__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 2 / 1;
  object-fit: cover;
  border: 1px solid var(--line);
  background: var(--ink-2);
}

.page-disclaimer .usage-hero__figcap {
  margin: 10px 0 0;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--dim);
}

/* ---------- 目录 ---------- */

.page-disclaimer .usage-toc {
  margin-top: clamp(24px, 4vw, 40px);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-disclaimer .usage-toc__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--paper);
}

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

.page-disclaimer .usage-toc__hint {
  color: var(--lava);
}

.page-disclaimer .usage-toc__body {
  display: none;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
}

.page-disclaimer .usage-toc[open] .usage-toc__body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
}

.page-disclaimer .usage-toc__body li {
  display: contents;
}

.page-disclaimer .usage-toc__body a {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line);
  color: var(--ash);
  text-decoration: none;
  font-size: 15px;
  transition: color 0.2s var(--ease);
}

.page-disclaimer .usage-toc__body a:hover,
.page-disclaimer .usage-toc__body a:focus-visible {
  color: var(--lava);
}

.page-disclaimer .usage-toc__no {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--lava);
}

.page-disclaimer .usage-toc__txt {
  color: inherit;
}

/* ---------- 章节 ---------- */

.page-disclaimer .usage-sec {
  margin-top: clamp(52px, 8vw, 104px);
  padding-top: clamp(22px, 3vw, 34px);
  border-top: 1px solid var(--line);
}

.page-disclaimer .usage-sec:first-of-type {
  margin-top: clamp(48px, 7vw, 92px);
}

.page-disclaimer .usage-sec__head {
  display: flex;
  align-items: baseline;
  gap: clamp(12px, 2vw, 22px);
}

.page-disclaimer .usage-sec__no {
  font-size: clamp(26px, 4.4vw, 42px);
  line-height: 1;
  color: var(--lava);
  letter-spacing: -0.02em;
  flex: none;
}

.page-disclaimer .usage-sec__title {
  font-size: clamp(24px, 3.4vw, 38px);
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--paper);
  margin: 0;
}

.page-disclaimer .usage-list {
  list-style: none;
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
}

.page-disclaimer .usage-item {
  padding: 16px 0;
  border-top: 1px solid var(--line);
}

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

.page-disclaimer .usage-item__no {
  display: block;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--lava);
  margin-bottom: 8px;
}

.page-disclaimer .usage-item__title {
  font-size: clamp(16px, 1.8vw, 18px);
  font-weight: 700;
  line-height: 1.45;
  color: var(--paper);
  margin: 0 0 8px;
}

.page-disclaimer .usage-item p {
  font-size: 15px;
  line-height: 1.78;
  color: var(--ash);
  margin: 0;
  max-width: 40ch;
}

.page-disclaimer .usage-item p a {
  color: var(--sky);
  text-decoration: none;
  border-bottom: 1px solid rgba(79, 168, 216, 0.4);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-disclaimer .usage-item p a:hover,
.page-disclaimer .usage-item p a:focus-visible {
  color: var(--ember);
  border-bottom-color: var(--ember);
}

/* ---------- 反馈区块 ---------- */

.page-disclaimer .usage-feedback {
  margin-top: clamp(60px, 9vw, 118px);
  margin-bottom: clamp(44px, 7vw, 86px);
  background: var(--paper);
  color: var(--ink);
  border: 1px solid var(--line);
  padding: clamp(24px, 4vw, 52px);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 32px);
}

.page-disclaimer .usage-feedback__tag {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--lava);
  margin: 0 0 10px;
}

.page-disclaimer .usage-feedback__title {
  font-size: clamp(24px, 3.6vw, 40px);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin: 0;
}

.page-disclaimer .usage-feedback__lead {
  font-size: 15px;
  line-height: 1.78;
  color: var(--usage-fb-muted);
  margin: 0 0 20px;
  max-width: 48ch;
}

.page-disclaimer .usage-feedback__contacts {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid rgba(18, 16, 15, 0.18);
}

.page-disclaimer .usage-feedback__contacts li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 16px;
  padding: 10px 0;
  border-bottom: 1px solid rgba(18, 16, 15, 0.18);
}

.page-disclaimer .usage-feedback__k {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--lava);
  flex: none;
  min-width: 68px;
}

.page-disclaimer .usage-feedback__v {
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink);
  word-break: break-word;
}

.page-disclaimer .usage-feedback__note {
  margin: 16px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--usage-fb-muted);
}

/* ---------- 焦点样式 ---------- */

.page-disclaimer a:focus-visible {
  outline: 2px solid var(--lava);
  outline-offset: 3px;
}

/* ---------- 平板与桌面 ---------- */

@media (min-width: 768px) {
  .page-disclaimer .usage-hero {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    column-gap: var(--usage-gap);
    align-items: end;
  }

  .page-disclaimer .usage-hero__side {
    padding-bottom: 6px;
  }

  .page-disclaimer .usage-toc__summary {
    display: none;
  }

  .page-disclaimer .usage-toc__body,
  .page-disclaimer .usage-toc[open] .usage-toc__body {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    padding: 0;
  }

  .page-disclaimer .usage-toc__body a {
    padding: 16px 18px;
    border-bottom: 0;
    border-right: 1px solid var(--line);
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    height: 100%;
  }

  .page-disclaimer .usage-toc__body li:first-child a {
    padding-left: 0;
  }

  .page-disclaimer .usage-toc__body li:last-child a {
    border-right: 0;
    padding-right: 0;
  }

  .page-disclaimer .usage-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-disclaimer .usage-item {
    padding: 20px 28px;
    border-top: 1px solid var(--line);
    border-left: 1px solid var(--line);
  }

  .page-disclaimer .usage-item:nth-child(odd) {
    border-left: 0;
    padding-left: 0;
  }

  .page-disclaimer .usage-item:nth-child(even) {
    padding-right: 0;
  }

  .page-disclaimer .usage-item:first-child,
  .page-disclaimer .usage-item:nth-child(2) {
    border-top: 0;
    padding-top: 0;
  }

  .page-disclaimer .usage-item p {
    max-width: 36ch;
  }

  .page-disclaimer .usage-feedback {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    column-gap: var(--usage-gap);
    align-items: start;
  }
}

@media (min-width: 1100px) {
  .page-disclaimer .usage-hero__title {
    font-size: clamp(96px, 9vw, 132px);
  }

  .page-disclaimer .usage-sec {
    display: grid;
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    column-gap: var(--usage-gap);
    align-items: start;
  }

  .page-disclaimer .usage-sec__head {
    position: sticky;
    top: 32px;
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
  }

  .page-disclaimer .usage-list {
    margin-top: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-disclaimer .usage-toc__body a,
  .page-disclaimer .breadcrumb a,
  .page-disclaimer .usage-item p a {
    transition: none;
  }
}