/* Composition layer, loaded last: chapter rehearsal marks, three surface levels, a steadier rhythm and readable measures. */
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@media(min-width:1700px){:root{--pad:max(var(--gutter),calc((100vw - 1500px)/2))}}

/* Surfaces: chapters share one paper, figures rise to white, tools stay dark. The planned film is the only tinted interlude. */
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.section{padding-block:72px 128px}
.section:not(.ink)::before{content:"";position:absolute;top:0;left:var(--pad);right:var(--pad);height:1px;background:var(--rule)}
.ink+.section::before,#overview::before,.demo-plan::before{display:none}
#overview{padding-top:104px}
.demo-plan{background:#e7eef7;padding-top:104px}

/* Chapter openings: a boxed rehearsal mark, as in an ensemble score, then the chapter name. */
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.ink .chapter-mark{color:#e4ecf8}.ink .chapter-mark .mark{border-color:var(--cyan);color:var(--cyan);background:transparent}
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.ink .intro-note{color:#b3c5df}
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/* Measures: captions and notes stop before they become hard to track. */
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.model-scope p{max-width:70ch}

/* Opening: the product, the claim and the label fit one screen. */
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/* Panel hierarchy: large instruments and figures at 12px, photographs at 8px. */
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/* Readable minimum sizes. These follow the earlier stylesheets' selectors so one set holds at every width. */
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@media(max-width:1080px){.section{padding-block:64px 104px}}
@media(max-width:760px){
.section{padding-block:44px 76px}
#overview,.demo-plan{padding-top:72px}
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