.page-header{
  padding: 170px 0 70px;
  border-bottom: 1px solid var(--line-soft);
}

.page-header h1{
  font-size: clamp(2.2rem, 4.5vw, 3.2rem);
  margin-top: 16px;
}

.page-header p{
  color: var(--ink-dim);
  margin-top: 16px;
  max-width: 560px;
  font-size: 1.02rem;
}

.rules-layout{
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 60px;
  align-items: flex-start;
}

.rules-nav{
  position: sticky;
  top: 100px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.rules-nav a{
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--ink-dim);
  padding: 10px 14px;
  border-left: 2px solid var(--line-soft);
  transition: all 0.2s ease;
}

.rules-nav a:hover{
  color: var(--white);
  border-left-color: var(--blue-dim);
}

.rules-nav a.active{
  color: var(--blue-bright);
  border-left-color: var(--blue-bright);
  background: rgba(63,107,255,0.06);
}

.rule-set{
  margin-bottom: 66px;
}

.rule-set-head{
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 24px;
}

.rule-set-head h2{
  font-size: 1.5rem;
}

.rule-set-count{
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--ink-dim);
}

.rule-list{
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--line-soft);
}

.rule-item{
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 18px;
  padding: 18px 4px;
  border-bottom: 1px solid var(--line-soft);
  align-items: center;
}

.rule-num{
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--blue-bright);
}

.rule-text{
  font-size: 0.98rem;
  color: var(--ink);
}

.rule-note{
  margin-top: 28px;
  padding: 20px 24px;
  border: 1px solid var(--line);
  background: var(--panel);
  font-size: 0.9rem;
  color: var(--ink-dim);
  display: flex;
  gap: 14px;
}

.rule-note b{
  color: var(--blue-bright);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  flex-shrink: 0;
}

@media (max-width: 860px){
  .rules-layout{
    grid-template-columns: 1fr;
    gap: 30px;
  }
  .rules-nav{
    position: static;
    flex-direction: row;
    overflow-x: auto;
    gap: 8px;
    padding-bottom: 8px;
  }
  .rules-nav a{
    border-left: none;
    border-bottom: 2px solid var(--line-soft);
    white-space: nowrap;
  }
  .rules-nav a.active{
    border-bottom-color: var(--blue-bright);
  }
}