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var(--line)}.toc-title{font-family:var(--font-mono);font-size:.66rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);margin-bottom:12px}.toc ol{list-style:none;display:grid;gap:2px}.toc button{position:relative;display:block;width:100%;padding:6px 0;text-align:left;font-size:.875rem;line-height:1.4;color:var(--muted);transition:color .2s}.toc button:hover{color:var(--ink)}.toc button.active{color:var(--ink);font-weight:500}.toc button.active:before{content:"";position:absolute;left:-21px;top:6px;bottom:6px;width:2px;background:var(--ink);border-radius:2px}@media(max-width:1180px){.reader{grid-template-columns:minmax(0,var(--measure));justify-content:start}.toc{display:none}}@media(max-width:640px){.reading{font-size:1.0625rem;line-height:1.7}.reading .lead{margin-bottom:32px;padding-bottom:28px}.example,.takeaway{padding:22px 20px}.terms{grid-template-columns:1fr}}.lesson-study{max-width:820px}.lesson-finish{position:relative;margin-top:8px;padding:36px;border:1px 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