/* Chapter 3 keeps the typography and network vocabulary of Chapters 1–2. */
.atlas-map{height:clamp(700px,calc(100svh - 255px),760px)}
.core-link{left:48%;top:43%}
.map-gravity-elasticity{left:3%;top:3%;width:270px}.map-friction{right:3%;top:3%;width:270px}.map-newton{right:3%;top:31%;width:270px}.map-composition{left:3%;top:62%;width:270px}.map-equilibrium{right:3%;top:62%;width:270px}
.map-gravity-elasticity .group-port,.map-composition .group-port{left:auto;right:-16px}
.atlas-map .chapter-bridge[data-journey=previous]{top:45%;width:32%}
.planned-badge{font-size:10px;color:#8e9ca4;white-space:nowrap;margin-left:auto;letter-spacing:.04em}.map-topics a{white-space:normal}.is-planned .group-heading{padding-bottom:12px}
#knowledge-network[data-active=gravity-elasticity] [data-branch=gravity-elasticity],#knowledge-network[data-active=friction] [data-branch=friction],#knowledge-network[data-active=newton] [data-branch=newton],#knowledge-network[data-active=composition] [data-branch=composition],#knowledge-network[data-active=equilibrium] [data-branch=equilibrium]{stroke:#e7c58e91;filter:drop-shadow(0 0 3px #e7c58e35)}

/* Diagrams and facts carry the content; captions identify results and conditions. */
.key-copy{padding-top:8px}.key-copy h2{margin-top:0}.key-copy p+p{margin-top:16px}
.diagram-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:28px;margin:24px 0 30px;align-items:start}.diagram-card{min-width:0;padding:18px 16px 16px;border:1px solid var(--line);border-radius:3px;background:#12233116}.diagram-card h3{font-size:16px;color:var(--accent);margin:0 0 14px}.diagram-card figcaption{font-size:14px;color:#bdcbd1;line-height:1.8;margin:12px 0 0}.diagram-card p{font-size:14px;margin-top:14px;color:#bdcbd1}.diagram-grid>.diagram-card:only-child{grid-column:1/-1;max-width:520px;width:100%}.diagram text{font-size:19px}.diagram .tick{font-size:17px}.diagram .grid{stroke:#a4c5d32b}
.key-facts{margin:25px 0;padding:0}.key-facts>div{display:grid;grid-template-columns:100px minmax(0,1fr);gap:16px;padding:13px 0;border-bottom:1px solid var(--line)}.key-facts dt{font-weight:500;color:var(--accent)}.key-facts dd{margin:0}.key-facts>p{margin:12px 0}.key-facts>p strong{color:var(--accent)}.key-note{border-left:2px solid var(--accent);padding:8px 0 8px 18px;margin-top:26px;font-size:15px}.law-statement{font-size:18px;margin-bottom:25px}.law-statement strong{color:var(--accent)}.knowledge-list{padding-left:22px;margin:18px 0}.knowledge-list li{padding:3px 0 9px 3px}.analysis-steps{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px 30px;margin:0;padding-left:24px}.analysis-steps li{padding-left:5px}.analysis-steps strong{display:block;color:var(--accent);margin-bottom:5px}.analysis-steps span{font-size:14px}
.chapter-table{width:100%;border-collapse:collapse;text-align:left;font-size:15px}.chapter-table th,.chapter-table td{padding:15px 13px;border-bottom:1px solid var(--line);vertical-align:top}.chapter-table th{font-weight:500;color:var(--accent)}.chapter-table td{color:#c6d2d7}.table-scroll{overflow:auto;margin:25px 0}.comparison-table{table-layout:fixed}.comparison-table th:first-child{width:18%}.comparison-table .formula-trigger{font-size:23px;padding:5px 0}.comparison-table .formula-textbook .formula-math{padding:10px 12px}.display-math{overflow-x:auto;max-width:100%;margin:18px 0}.display-math .katex-display{text-align:left;margin:0}.formula-legend{margin-bottom:18px}.formula-rows{margin-bottom:24px}
/* Shared handbook type and colours; the requested illustrations sit on the right. */
.handbook-heading{margin-bottom:18px}.handbook-content .formula-legend{margin-bottom:24px}
.formula-rows article.formula-with-diagram{grid-template-columns:minmax(0,1.08fr) minmax(0,1fr)}.formula-with-diagram figure{max-width:330px;width:100%;justify-self:center}.formula-with-diagram figcaption{text-align:center}.equal-angle-results{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));text-align:center;gap:0;color:var(--accent);font-size:18px;margin-top:0}.equal-angle-figure figcaption{text-align:center;margin-top:22px}
.quick-row.quick-illustrated{grid-template-columns:minmax(0,1fr) minmax(270px,40%);gap:28px;padding:24px 0;align-items:center}.quick-copy{min-width:0}.quick-label{display:block;font-size:13px;color:#b8c7ce}.quick-copy>p{font-size:12px;color:var(--muted);line-height:1.9;max-width:360px}.quick-figure{margin:0;width:100%;max-width:400px;justify-self:end}.quick-figure figcaption{font-size:12px;line-height:1.8;text-align:center;margin-top:8px}.quick-figure .diagram{max-height:270px;object-fit:contain}.quick-figure .diagram text{font-size:20px}
@media(min-width:761px) and (max-width:1050px){.quick-row.quick-illustrated{grid-template-columns:minmax(0,1fr) minmax(220px,43%);gap:16px}.quick-figure .diagram text{font-size:21px}}
@media(max-width:760px){.formula-rows article.formula-with-diagram{grid-template-columns:1fr;gap:16px}.quick-row.quick-illustrated{grid-template-columns:minmax(0,1fr);gap:12px;padding:22px 0}.quick-figure{justify-self:center;max-width:360px}.quick-copy>p{max-width:none}.equal-angle-results{font-size:14px}}
@media(min-width:1250px){.diagram-grid:has(>.diagram-card:nth-child(3):last-child){grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.diagram-grid:has(>.diagram-card:nth-child(3):last-child)>.diagram-card{padding:14px 10px}}
@media(min-width:761px) and (max-width:1050px){.atlas-map{height:760px}.core-link{left:47%;top:43%}.map-gravity-elasticity{left:0;top:3%;width:210px}.map-friction{right:0;top:3%;width:210px}.map-newton{right:0;top:29%;width:210px}.map-composition{left:0;top:62%;width:230px}.map-equilibrium{right:0;top:62%;width:230px}.atlas-map .chapter-bridge[data-journey=previous]{top:45%;width:32%}.group-heading{gap:8px}.planned-badge{font-size:9px}.diagram-grid{gap:18px}.diagram-card{padding:14px 9px}.key-facts>div{grid-template-columns:88px minmax(0,1fr);gap:12px}}
@media(max-width:760px){.atlas-map{height:auto;gap:27px}.core-link{left:auto;top:auto;width:190px;height:190px}.map-gravity-elasticity,.map-friction,.map-newton,.map-composition,.map-equilibrium{position:relative;left:auto;right:auto;top:auto;bottom:auto;width:100%}.map-gravity-elasticity .group-port,.map-composition .group-port{left:-22px;right:auto}.atlas-map .chapter-bridge[data-journey=previous]{top:auto;width:100%}.map-equilibrium:before{bottom:8px}.planned-badge{font-size:10px}.diagram-grid{grid-template-columns:1fr;gap:20px}.diagram-card{padding:17px 12px}.key-facts>div{grid-template-columns:76px minmax(0,1fr);gap:12px}.chapter-table{font-size:14px}.chapter-table th,.chapter-table td{padding:12px 8px}.comparison-table th:first-child{width:19%}.comparison-table .formula-trigger{font-size:19px}.comparison-table .formula-textbook .formula-math{padding:8px}.law-statement{font-size:17px}.analysis-steps{grid-template-columns:1fr;gap:16px}.diagram-card figcaption{font-size:14px}.key-copy{padding-top:0}}

.force-intro{align-items:center}.force-intro .key-facts{margin:0}.force-intro .key-facts>div{grid-template-columns:76px minmax(0,1fr);padding:10px 0}

.proof{margin:22px 0}.proof>summary{color:var(--accent);cursor:pointer;font-size:14px;padding:10px 0}.proof-body>.diagram{max-width:520px;display:block;margin:20px auto}