/* MOSAIC Chemistry companion to the existing Biology page: same class structure, standalone fallback. */
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*{box-sizing:border-box}html{scroll-padding-top:98px}body{margin:0;background:var(--bg);color:var(--ink);font-family:'DM Sans',system-ui,-apple-system,sans-serif;line-height:1.68;overflow-x:hidden}h1,h2,h3,h4,h5{font-family:'Space Grotesk','DM Sans',sans-serif;line-height:1.26;color:#27314c}a{color:inherit;text-decoration:none}a:focus-visible{outline:3px solid #8261ec;outline-offset:4px}img{max-width:100%;height:auto}
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.topic{margin:0 0 70px;scroll-margin-top:90px}.topic-heading{margin:0 0 21px}.topic-number{display:inline-block;border-radius:999px;background:#e9e2ff;color:#684ac3;font-weight:800;padding:5px 14px;font-size:.85rem;margin-bottom:10px}.topic-heading h2{font-size:clamp(1.8rem,3vw,2.65rem);letter-spacing:-.035em;margin:7px 0 10px}.big-question{border-left:4px solid #8d6bda;padding:10px 16px;margin:13px 0 0;color:#526178;background:#f1edff;border-radius:0 9px 9px 0}.lesson-jump{padding:20px 24px;background:#fff;border:1px solid #e5e7f3;border-radius:16px;margin:0 0 26px}.lesson-jump>span{display:block;font-size:.83rem;font-weight:800;text-transform:uppercase;letter-spacing:.08em;color:#7b66ae;margin-bottom:10px}.lesson-jump-links{display:flex;gap:8px;flex-wrap:wrap}.lesson-jump-links a{border:1px solid #e7e4ef;border-radius:10px;padding:7px 11px;font-size:.81rem;font-weight:650;color:#625679;background:#fbfaff}.lesson-jump-links a[aria-current]{background:#e5ddff;border-color:#bca6f7;color:#593bb1}
.lesson-stack{display:grid;gap:26px}.lesson-card{background:#fff;border:1px solid #e6e9f2;box-shadow:var(--shadow);border-radius:22px;padding:clamp(20px,3.5vw,39px);scroll-margin-top:98px;min-width:0}.lesson-kicker{color:#8059db;font-size:.77rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase}.lesson-card h3{font-size:clamp(1.35rem,2.2vw,1.95rem);line-height:1.32;margin:10px 0 20px}.lesson-card figure{margin:12px 0 22px;max-width:100%;padding:0;overflow:visible;text-align:center}.lesson-card figure img{display:block;width:100%;max-width:920px;height:auto;aspect-ratio:4/3;object-fit:contain;border-radius:13px;margin:0 auto;background:white;border:1px solid #eceff5}.lesson-card figcaption{color:#778298;font-size:.75rem;margin:9px auto 0}.lesson-text{max-width:100%;min-width:0;color:#36445d;font-size:1rem;line-height:1.66}.lesson-text h4{font-size:1.17rem;margin:25px 0 10px}.lesson-text h5{font-size:1rem;margin:19px 0 8px;font-weight:800}.lesson-text p{margin:0 0 11px;max-width:100%;overflow-wrap:anywhere}.lesson-text .instruction-lead{font-weight:750;margin-top:14px}.lesson-text .equation{display:block;width:fit-content;max-width:100%;padding:6px 14px;border:1px solid #dcdafa;background:#f5f3ff;border-radius:8px;color:#5847b4;font-weight:750;font-size:.96rem;white-space:normal;overflow-wrap:anywhere}.lesson-text .diagram-arrow{font-size:1.4rem;font-weight:900;color:#8a64d5;margin:0 0 7px 18px}.table-scroll{max-width:100%;overflow-x:auto;-webkit-overflow-scrolling:touch;margin:19px 0 24px;border-radius:12px;border:1px solid #e0e5ed}.vocab-table{border-collapse:collapse;width:100%;background:white;table-layout:auto;font-size:.91rem;text-align:left;line-height:1.45}.vocab-table th,.vocab-table td{border:1px solid #e1e5ee;padding:12px 13px;vertical-align:top;overflow-wrap:anywhere}.vocab-table thead th{background:#f2edff;color:#5641a6;font-weight:800}.vocab-table tbody th{min-width:120px;font-weight:750;background:#fcfbff;color:#37415e}.lesson-card-footer{margin-top:25px;padding-top:16px;display:flex;justify-content:space-between;gap:14px;border-top:1px solid #ebedf4;font-size:.82rem;font-weight:750;color:#7957d2}
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@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}


/* Chemistry: Large centered images */

.lesson-stack .lesson-card {
  display: flex;
  flex-direction: column;
  align-items: stretch;
}

/* Center and enlarge each illustration */
.lesson-stack .lesson-card > figure {
  width: 100%;
  max-width: 1050px;
  margin: 24px auto 32px;
  text-align: center;
}

/* Show the complete image without cropping */
.lesson-stack .lesson-card > figure img {
  display: block;
  width: 100%;
  max-width: none;
  height: auto;
  aspect-ratio: auto;
  object-fit: contain;
  margin: 0 auto;
}

/* Put vocabulary and explanations below */
.lesson-stack .lesson-card > .lesson-text {
  width: 100%;
  max-width: 1000px;
  margin: 0 auto;
  min-width: 0;
}

/* Center image captions */
.lesson-stack .lesson-card figcaption {
  text-align: center;
  margin-top: 12px;
}

/* Mobile */
@media (max-width: 760px) {
  .lesson-stack .lesson-card > figure {
    width: 100%;
    margin: 18px auto 24px;
  }

  .lesson-stack .lesson-card > figure img {
    width: 100%;
    height: auto;
  }
}