.page-disclaimer {
  --usage-num-col: 3.5rem;
  --usage-rule: rgba(124, 138, 131, 0.22);
  display: block;
  padding-bottom: clamp(2.5rem, 6vw, 5rem);
}

/* ---------- 首屏 ---------- */
.page-disclaimer .usage-hero {
  display: grid;
  gap: clamp(1.25rem, 3.5vw, 2.75rem);
  padding: clamp(1.25rem, 3vw, 2rem) 0 clamp(1.75rem, 4vw, 2.75rem);
  border-bottom: 1px solid var(--line);
}

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

.page-disclaimer .usage-hero h1 {
  margin: 0.6rem 0 0;
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: clamp(1.75rem, 5.4vw, 3.15rem);
  line-height: 1.14;
  letter-spacing: -0.015em;
  color: var(--paper-2);
  max-width: 22ch;
}

.page-disclaimer .usage-hero .lede {
  margin: clamp(0.9rem, 2vw, 1.35rem) 0 0;
  max-width: 46ch;
  font-family: var(--font-serif);
  font-size: clamp(1rem, 1.7vw, 1.125rem);
  line-height: 1.8;
  color: var(--text);
}

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

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

/* ---------- 目录：米白纸面 ---------- */
.page-disclaimer .usage-toc {
  margin: clamp(1.5rem, 4vw, 2.5rem) 0 clamp(1.75rem, 4vw, 2.75rem);
  padding: clamp(1.15rem, 3vw, 1.9rem);
  background: var(--paper);
  color: var(--ink-950);
  border: 1px solid var(--ink-950);
  box-shadow: 7px 7px 0 rgba(16, 20, 19, 0.5);
}

.page-disclaimer .usage-toc__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.85rem;
  padding-bottom: 0.9rem;
  border-bottom: 1px solid rgba(16, 20, 19, 0.28);
}

.page-disclaimer .usage-toc__title {
  margin: 0;
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: clamp(0.95rem, 2vw, 1.1rem);
  letter-spacing: 0.06em;
  color: var(--ink-950);
}

.page-disclaimer .usage-toc__list {
  list-style: none;
  margin: 0.5rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
}

.page-disclaimer .usage-toc__list li + li {
  border-top: 1px solid rgba(16, 20, 19, 0.14);
}

.page-disclaimer .usage-toc__list a {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  padding: 0.7rem 0.35rem;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  line-height: 1.5;
  color: var(--ink-950);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: background-color var(--dur) ease, border-color var(--dur) ease;
}

.page-disclaimer .usage-toc__list a:hover {
  background: rgba(16, 20, 19, 0.06);
  border-bottom-color: var(--warm);
}

.page-disclaimer .usage-toc__list a:focus-visible {
  outline: 2px solid var(--ink-950);
  outline-offset: 2px;
}

.page-disclaimer .usage-toc__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: rgba(16, 20, 19, 0.56);
}

/* ---------- 条款主体 ---------- */
.page-disclaimer .usage-body {
  border-top: 1px solid var(--usage-rule);
}

.page-disclaimer .usage-clause {
  display: grid;
  grid-template-columns: var(--usage-num-col) minmax(0, 1fr);
  gap: clamp(0.6rem, 2vw, 1.75rem);
  padding: clamp(1.35rem, 3vw, 2.1rem) clamp(0.4rem, 1.4vw, 0.9rem);
  border-bottom: 1px solid var(--usage-rule);
  scroll-margin-top: 6.5rem;
  transition: background-color var(--dur) ease, box-shadow var(--dur) ease;
}

.page-disclaimer .usage-clause:target {
  background: var(--accent-soft);
  box-shadow: inset 3px 0 0 var(--accent);
}

.page-disclaimer .usage-clause__num {
  font-family: var(--font-mono);
  font-size: clamp(0.85rem, 1.6vw, 1.05rem);
  letter-spacing: 0.06em;
  color: var(--muted);
  padding-top: 0.22em;
}

.page-disclaimer .usage-clause:target .usage-clause__num {
  color: var(--accent);
}

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

.page-disclaimer .usage-clause__title {
  margin: 0 0 0.7rem;
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: clamp(1.1rem, 2.6vw, 1.42rem);
  line-height: 1.32;
  letter-spacing: -0.01em;
  color: var(--paper-2);
}

.page-disclaimer .usage-clause__content p {
  margin: 0 0 0.85rem;
  max-width: 64ch;
  font-family: var(--font-serif);
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text);
}

.page-disclaimer .usage-clause__content p:last-child {
  margin-bottom: 0;
}

.page-disclaimer .usage-mark {
  font-style: normal;
  border-bottom: 2px solid var(--accent);
  padding-bottom: 1px;
  color: var(--paper-2);
}

/* ---------- 引用写法面板 ---------- */
.page-disclaimer .usage-cite {
  margin-top: clamp(2rem, 5vw, 3.25rem);
  padding: clamp(1.15rem, 3vw, 2rem);
  background: var(--board);
  border: 1px solid var(--line-strong);
}

.page-disclaimer .usage-cite__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.85rem;
  padding-bottom: 0.9rem;
  border-bottom: 1px solid var(--line);
}

.page-disclaimer .usage-cite__title {
  margin: 0;
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: clamp(1rem, 2.2vw, 1.2rem);
  color: var(--paper-2);
}

.page-disclaimer .usage-cite__panel[hidden] {
  display: none;
}

.page-disclaimer .usage-cite__list {
  margin: 0.35rem 0 0;
  padding: 0;
}

.page-disclaimer .usage-cite__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.25rem 1.25rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--usage-rule);
}

.page-disclaimer .usage-cite__row:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-disclaimer .usage-cite__row dt {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.page-disclaimer .usage-cite__row dd {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 0.97rem;
  line-height: 1.75;
  color: var(--text);
}

/* ---------- 相关入口 ---------- */
.page-disclaimer .usage-related {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap);
  margin-top: clamp(2rem, 5vw, 3rem);
}

.page-disclaimer .usage-related .board-card {
  display: block;
  text-decoration: none;
  min-width: 0;
}

.page-disclaimer .usage-related .board-card__title {
  display: block;
}

/* ---------- 响应式 ---------- */
@media (max-width: 560px) {
  .page-disclaimer {
    --usage-num-col: 2.25rem;
  }

  .page-disclaimer .usage-toc {
    box-shadow: 4px 4px 0 rgba(16, 20, 19, 0.5);
  }
}

@media (min-width: 720px) {
  .page-disclaimer .usage-toc__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-disclaimer .usage-toc__list li:nth-child(2) {
    border-top: 0;
  }

  .page-disclaimer .usage-related {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-disclaimer .usage-cite__row {
    grid-template-columns: 12rem minmax(0, 1fr);
    align-items: baseline;
  }
}

@media (min-width: 900px) {
  .page-disclaimer .usage-hero {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: end;
  }

  .page-disclaimer .usage-clause {
    grid-template-columns: var(--usage-num-col) minmax(0, 1fr);
  }

  .page-disclaimer .usage-clause__num {
    font-size: 1.05rem;
  }
}