.back-link {
  color: var(--ink);
  font-size: 12px;
  font-weight: 700;
  text-decoration: none;
}

.site-header nav a[aria-current="page"] {
  color: var(--ink);
}

.rules-main {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 34px 120px;
}

.rules-hero {
  padding: 110px 0 76px;
  border-bottom: 1px solid var(--line);
}

.rules-hero h1 {
  max-width: 850px;
  margin: 20px 0 25px;
  font-size: clamp(58px, 9vw, 112px);
  line-height: .92;
  letter-spacing: -5px;
}

.rules-hero h1 em {
  color: var(--accent);
  font-family: var(--serif);
}

.rules-hero p {
  max-width: 650px;
  margin: 0;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.7;
}

.rules-layout {
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  gap: 70px;
  padding-top: 54px;
}

.rules-index {
  position: sticky;
  top: 24px;
  align-self: start;
  display: grid;
  gap: 13px;
}

.rules-index span {
  margin-bottom: 7px;
  color: var(--muted);
  font: 500 10px var(--mono);
  letter-spacing: 1px;
  text-transform: uppercase;
}

.rules-index a {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
}

.rules-index a:hover {
  color: var(--accent);
}

.rules-content {
  min-width: 0;
}

.rule-section {
  display: grid;
  grid-template-columns: 60px minmax(0, 1fr);
  gap: 22px;
  padding: 38px 0 43px;
  border-top: 1px solid var(--line);
  scroll-margin-top: 24px;
}

.rule-section:first-child {
  padding-top: 0;
  border-top: 0;
}

.rule-number {
  padding-top: 5px;
  color: var(--accent);
  font: 500 11px var(--mono);
}

.rule-section h2 {
  margin: 0 0 15px;
  font-size: 24px;
  letter-spacing: 0;
}

.rule-section p {
  max-width: 700px;
  margin: 10px 0 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.75;
}

@media (max-width: 700px) {
  .site-header nav {
    display: none;
  }

  .back-link {
    font-size: 11px;
  }

  .rules-main {
    padding: 0 20px 80px;
  }

  .rules-hero {
    padding: 75px 0 52px;
  }

  .rules-hero h1 {
    font-size: 56px;
    letter-spacing: -3px;
  }

  .rules-hero p {
    font-size: 15px;
  }

  .rules-layout {
    grid-template-columns: 1fr;
    gap: 35px;
    padding-top: 35px;
  }

  .rules-index {
    position: static;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px 16px;
    padding-bottom: 30px;
    border-bottom: 1px solid var(--line);
  }

  .rules-index span {
    grid-column: 1 / -1;
  }

  .rule-section {
    grid-template-columns: 35px minmax(0, 1fr);
    gap: 12px;
    padding: 30px 0 34px;
  }

  .rule-section h2 {
    font-size: 20px;
  }

  footer {
    gap: 18px;
    text-align: center;
  }
}