#rules {
  box-sizing: border-box;
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px 28px 40px;

  .rules_header {
    margin-bottom: 20px;

    .page_subtitle {
      margin: 0 0 6px;
    }

    p {
      margin: 0;
      color: #647181;
      line-height: 1.4;
    }
  }

  .rules_layout {
    display: grid;
    grid-template-columns: minmax(190px, 240px) minmax(0, 1fr);
    align-items: start;
    gap: 20px;
  }

  .rules_topics, .rule {
    min-width: 0;
    border: 1px solid #d8e0e8;
    border-radius: 12px;
    background: #fff;
    box-shadow: 0 2px 8px rgba(25, 48, 68, 0.06);
  }

  .rules_topics {
    padding: 16px;

    h3 {
      margin: 0 0 12px;
      color: #526171;
      font: 17px 'Acme';
    }
  }

  #rules_nav {
    display: grid;
    gap: 4px;
    margin: 0;
    list-style: none;

    .rule_nav_link {
      display: block;
      padding: 10px 12px;
      border-radius: 7px;
      color: #34475a;
      font: 16px 'Acme';
      text-decoration: none;

      &:hover, &:focus-visible {
        background: #eef5fb;
        color: #176b96;
      }

      &:focus-visible {
        outline: 2px solid var(--btn-primary);
        outline-offset: 2px;
      }

      &.selected {
        background: #eaf4fb;
        color: #176b96;
      }
    }
  }

  .rule {
    padding: 24px;
    color: #34475a;
    font-size: 16px;
    line-height: 1.6;
    overflow-wrap: anywhere;
    overflow-x: auto;

    h3 {
      margin: 0 0 18px;
      padding-bottom: 12px;
      border-bottom: 1px solid #e3e9ef;
      color: #263746;
      font: 28px 'Acme';
    }

    h4 {
      margin: 24px 0 8px;
      color: #263746;
      font: 21px 'Acme';
    }

    h5 {
      margin: 18px 0 6px;
      color: #34475a;
      font-size: 16px;
      font-weight: 700;
    }

    p {
      margin: 0 0 14px;
    }

    ul, ol {
      margin: 0 0 16px 24px;
      list-style-position: outside;
    }

    ul {
      list-style-type: disc;
    }

    ol {
      list-style-type: decimal;
    }

    li {
      margin-bottom: 6px;
    }

    a {
      color: #176b96;
      font-weight: 700;
      text-decoration: underline;

      &:hover {
        color: #0e4d71;
      }
    }

    strong {
      color: #263746;
      font-weight: 700;
    }

    em {
      font-style: italic;
    }

    .example {
      margin: 16px 0;
      padding: 14px 16px;
      border-left: 4px solid var(--btn-primary);
      border-radius: 0 8px 8px 0;
      background: #eef7fc;
      font-size: 0.9em;
    }

    img {
      max-width: 100%;
      height: auto;
    }

    pre {
      max-width: 100%;
      overflow-x: auto;
    }
  }
}

@media (max-width: 700px) {
  #rules {
    padding: 20px 14px 32px;

    .rules_layout {
      grid-template-columns: 1fr;
      gap: 14px;
    }

    .rules_topics {
      padding: 14px;
    }

    #rules_nav {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;

      .rule_nav_link {
        padding: 8px 10px;
      }
    }

    .rule {
      padding: 18px;
    }
  }
}