/* Study pages: an open brief, a chapter bookmark, attached source pages and an
   answer slip. Existing lesson text and anatomical materials are unchanged. */
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.lab-brief .lab-purpose { font-size:1.2rem;line-height:1.55;margin-bottom:1.8rem;color:var(--ua-ink); }
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/* Keep the progress line independent of the moving lesson content. It means
   position in this walkthrough, never completion or verified knowledge. */
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.lesson-content { min-width:0; }
#lesson-reading { overflow-x:clip; }
.lesson-content #lesson-title { margin-top:0; }
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.guided-learning .chapter-advance .walk-navigation { display:contents; }
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.guided-learning .chapter-advance #walk-check { grid-column:2;grid-row:2;justify-self:start; }

/* The source pages remain exact pages; paper edges and the page tab explain
   the physical document without importing or fabricating its content. */
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/* A station is one paper surface. The question may arrive, but the response
   field and its controls are separate, stationary interaction targets. */
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#practice-options { margin-bottom:1.2rem; }
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}
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  .station-response #station-answer { font-size:1rem; }
}
@media(max-width:400px) {
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}