:root{color-scheme:dark;--bg:#0c1220;--surface:#111a2a;--surface2:#172237;--surface3:#1c2a40;--text:#e7edf8;--muted:#91a0b8;--border:#263247;--accent:#75dfca;--purple:#b19cff;--paper:#fff;--stage:#0d1729;--shadow:0 12px 36px #0002;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif}
:root[data-theme=light]{color-scheme:light;--bg:#f6f2e9;--surface:#fffdf8;--surface2:#f1ede4;--surface3:#e9e3d7;--text:#302f2b;--muted:#6b675f;--border:#ded7ca;--accent:#236c61;--purple:#7651a1;--stage:#faf7ef;--shadow:0 12px 36px #54463009}
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html[data-theme=light] .chapter-heading h1{font-size:31px}
html[data-theme=light] .pdf-scroll{background:#e8e2d7}
html[data-theme=light] .visual-stage{background-image:radial-gradient(circle at 50% 45%,#fffef9,transparent 70%)}
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.teaching-readout{position:absolute;bottom:34px;left:12px;right:12px;pointer-events:none;text-align:center;font-family:'Cambria Math',Georgia,serif;font-size:13px;line-height:1.6;color:var(--text);background:var(--surface);border:1px solid var(--border);border-radius:5px;padding:4px 7px;box-shadow:0 2px 8px #0001}.visual-stage.is-teaching{height:350px}
@media(max-width:950px){.visual-stage.is-teaching{height:310px}}
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