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@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;transition:none!important;animation:none!important}}@media print{.topbar,.sidebar,.footer,.lesson-tabs,.lesson-nav,.book-mobile-index,.lesson-print,.quiz-actions{display:none!important}.book-layout,.reading-layout{display:block}.lesson-main,.reading-card{padding:0;border:0;background:white}.reading-aside{display:block}.side-note{margin-top:15px;break-inside:avoid}.example,.question{break-inside:avoid}.container{width:100%}body{color:black;font-size:12pt}.lab-visual{-webkit-print-color-adjust:exact;print-color-adjust:exact}.reading-card p{color:black}}

.solution summary{cursor:pointer;font-weight:700;color:var(--green);padding:8px 0}.solution[open] summary{margin-bottom:10px}
.visual-guide{border-block:1px solid var(--line);padding:24px 0;margin-block:24px}.conversion-rule{background:var(--paper);border-inline-start:4px solid var(--gold-ink);padding:18px;border-radius:8px}.conversion-rule p:last-child{margin:0}.conversion-rule strong{color:var(--navy)}.conversion-step{display:grid;grid-template-columns:minmax(0,1fr) minmax(70px,.8fr) minmax(0,1fr);align-items:center;gap:8px;margin:12px 0;padding:10px;background:var(--light);border:1px solid var(--line);border-radius:9px}.unit-node{text-align:center;font-size:1rem;font-weight:700;line-height:1.7;color:var(--navy)}.unit-node bdi{display:block;font:18px/1.8 Arial,sans-serif;direction:ltr}.conversion-arrow{display:flex;flex-direction:column;align-items:center;color:var(--navy)}.conversion-arrow bdi{font:700 20px/1.8 Arial,sans-serif;direction:ltr;white-space:nowrap}.conversion-arrow svg{width:100%;max-width:120px;height:22px;display:block}.conversion-example{border-bottom:1px solid var(--line);padding:12px 0}.conversion-example p{margin-bottom:7px}.area-laws{background:#edf3fb;border-radius:8px;padding:16px}.area-laws p{margin-bottom:8px}.area-laws p:last-child{margin:0}.practice-figure{margin:18px 0 24px;background:#f5f8fe;border:1px solid #cfdaec;border-radius:10px;padding:10px 14px 16px;break-inside:avoid}.practice-figure svg{display:block;width:100%;max-width:500px;height:auto;margin:auto}.practice-figure figcaption{font-size:.875rem;line-height:1.9;text-align:center;color:var(--muted)}.question-check{margin-top:15px;font-size:.875rem}.grid-lab{background:white;border:1px solid var(--line);border-radius:13px;padding:25px;margin-top:24px}.grid-lab h2{font-size:1.4rem}.grid-size{display:flex;align-items:center;gap:16px;flex-wrap:wrap;margin-bottom:20px}.grid-size input{width:100px;padding:7px;border:1px solid #bac7db;border-radius:6px;direction:ltr}.paint-grid{direction:ltr;display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:3px;max-width:348px;margin:20px auto}.paint-grid button{aspect-ratio:1;border:1.5px solid var(--blue);padding:0;background:white;border-radius:3px;min-width:0;color:var(--navy);font:700 20px/1 Arial}.paint-grid button[aria-pressed=true]{background:#a9c7f3}.grid-result{background:#edf3fb;margin-top:18px;padding:18px;border-radius:8px}.grid-result p{margin-bottom:8px}.grid-result p:last-child{margin:0}.math{max-width:100%;overflow-wrap:anywhere}.formula.formula-ar{direction:rtl;font-family:inherit;font-size:1.15rem}.quiz-card{scroll-margin-top:20px}
@media(max-width:700px){.grid-lab{padding:18px}.conversion-step{padding:8px 4px;gap:4px}.conversion-arrow bdi{font-size:18px}.example{padding:16px}.practice-figure{padding-inline:6px}.unit-node{font-size:.9rem}.visual-guide .notice{padding:14px}.conversion-rule{padding:14px}}
@media print{.practice-figure,.paint-grid button[aria-pressed=true],.conversion-rule{-webkit-print-color-adjust:exact;print-color-adjust:exact}.question-check{display:none}.quiz-card{break-inside:avoid}}

@media(max-width:700px){.practice-figure text{font-size:29px}.example .practice-figure{margin-inline:-12px;padding-inline:0;border:0;background:transparent}}

.height-lab{padding:25px;background:white;border:1px solid var(--line);border-radius:13px}.height-intro{margin-top:20px}.height-layout{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(220px,1fr);gap:25px;align-items:center}.height-legend{text-align:start;margin:5px 0 16px;display:grid;gap:8px;font-size:1rem;line-height:1.8}.height-legend>div{display:flex;align-items:baseline;gap:12px}.height-legend dt{font:700 18px Arial;min-width:24px;color:var(--navy)}.height-legend dd{margin:0;overflow-wrap:anywhere}.height-figure figcaption p{margin-bottom:0}.height-equation{direction:ltr;unicode-bidi:isolate;font:18px/1.9 Arial,sans-serif;overflow-wrap:anywhere;text-align:center;padding:12px}.height-figure svg{max-width:520px}
@media(max-width:1200px){.height-layout{grid-template-columns:1fr}.height-layout .controls-grid{grid-template-columns:1fr 1fr}}
@media(max-width:700px){.height-lab{padding:18px}.height-layout .controls-grid{grid-template-columns:1fr}.height-figure text{font-size:27px}.height-legend{font-size:1rem}.height-legend dt{font-size:18px}}
.audit-control{display:block;margin:18px 0;font-weight:600}.audit-control input{display:block;width:100%;margin-top:10px;accent-color:var(--navy,#102c61)}#audit-mode{display:block;padding:10px;max-width:100%;margin:12px 0}.source-card td a{display:inline-block;margin-bottom:6px}

/* Library integration: navigation, access form and focus indicators. */
.topbar nav{gap:22px;flex-wrap:wrap;justify-content:flex-end}
.library-return{font-weight:700}
.topbar nav .library-return{color:#806132;border:1px solid #d5bd92;border-radius:9px;padding:7px 12px}
#physics-access-dialog{border:1px solid #dfe5ef;border-top:5px solid #b58120;border-radius:20px;box-shadow:0 25px 90px #102c6133;padding:30px;width:min(470px,calc(100vw - 32px));max-height:calc(100svh - 36px);overflow:auto;color:#102c61;background:#fff;font-family:Cairo,Tahoma,Arial,sans-serif}
#physics-access-dialog::backdrop{background:#0b193dc9;backdrop-filter:blur(3px)}
#physics-access-dialog h2{font-size:1.6rem;line-height:1.6;margin-bottom:9px}
#physics-access-dialog p{font-size:.92rem;line-height:1.9;color:#536176;margin-bottom:15px}
#physics-access-dialog label{display:block;font-size:.92rem;font-weight:700;margin-bottom:8px}
#physics-access-dialog input{display:block;width:100%;padding:12px;border:1px solid #9eabc0;border-radius:10px;direction:ltr;text-align:center;background:#fff;color:#102c61;font-size:17px}
#physics-access-dialog input:focus-visible{outline:3px solid #d5b776;outline-offset:2px}
.physics-access-actions{display:flex;gap:10px;margin-top:18px}
.physics-access-actions button{flex:1;justify-content:center;min-height:46px;padding:10px;border-radius:10px;font-weight:700;font-size:.94rem}
#physics-access-message{min-height:28px;margin-top:12px;margin-bottom:0!important;color:#9b3626!important}
.physics-access-help{display:block;font-size:.8rem;color:#806132;margin-top:12px}
@media(max-width:900px) and (min-width:701px){.topbar{gap:12px}.topbar nav{font-size:.8rem;gap:10px}.topbar nav .library-return{padding:5px 7px}}
@media(max-width:700px){#physics-access-dialog{padding:24px}.footer #physics-logout{margin:10px auto}.footer>a:last-child{display:block;margin-top:12px}}