/* Foundations of Science II — Midterm 2 study guide */

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  /* Diagram accents: A = DNA / CRISPR, B = RNA / RNAi, C = warning / foreign */
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  --accent-c-soft: #2d2540;
  --ok: #79c99a;
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}

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }
[id] { scroll-margin-top: 72px; }

body {
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h1, h2, h3 { line-height: 1.25; }
h1 { font-size: 1.85rem; margin: 1.25rem 0 1.25rem; letter-spacing: -0.01em; }
h2 { font-size: 1.35rem; margin: 2.5rem 0 1rem; padding-top: 0.5rem; border-top: 1px solid var(--line); }
h3 { font-size: 1.1rem; margin: 1.75rem 0 0.5rem; }
a { color: var(--link); }
p, ul, ol { margin: 0 0 1.15rem; }
li { margin-bottom: 0.65rem; padding-left: 0.2rem; }
li::marker { color: var(--muted); }
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.lede { font-size: 1.15em; margin-bottom: 2rem; color: var(--fg); }
.lead-in { font-weight: 700; margin-bottom: 0.6rem; }

/* Each subsection is its own card, so the page reads as a stack of distinct topics. */
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  padding: 1.4rem 1.6rem 0.4rem;
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.block figure.diagram { background: var(--bg); }
.block .table-wrap { margin-bottom: 1.25rem; }

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/* ---------- Diagrams ---------- */

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figure.diagram svg { display: block; width: 100%; height: auto; max-width: 560px; margin: 0 auto; color: var(--fg); }
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tbody th { font-weight: 600; }

@media (max-width: 640px) {
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table.pairs.covered td:not(.revealed)::after {
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/* ---------- Practice questions ---------- */

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/* ---------- Flashcards ---------- */

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}
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.fc-side { font-size: 0.78rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); }
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button:disabled { opacity: 0.45; cursor: default; }