:root{--ink:#1d2625;--muted:#5b6662;--paper:#f5f4ef;--surface:#fff;--line:#ced6d1;--teal:#146c63;--deep-teal:#14342f;--coral:#d65a43;--gold:#d89a34;--blue:#3b729f;--violet:#705b9d}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--paper);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.5}button,input,select{font:inherit}button{cursor:pointer}a{color:inherit}.shell{width:min(1120px,calc(100% - 32px));margin:0 auto}.site-nav{display:flex;justify-content:space-between;align-items:center;gap:18px;min-height:68px;border-bottom:1px solid var(--line)}.brand{color:var(--deep-teal);font-size:.92rem;font-weight:850;text-decoration:none;letter-spacing:.02em}.nav-links{display:flex;align-items:center;gap:8px}.nav-link{min-height:36px;padding:7px 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i{position:absolute;width:40px;height:40px;border-radius:50%;background:var(--blue);border:2px solid var(--ink)}.rbm-preview i:nth-child(1){left:3%;top:0}.rbm-preview i:nth-child(2){left:3%;bottom:0;background:var(--gold)}.rbm-preview i:nth-child(3){left:48%;top:16px;background:var(--coral);width:48px;height:48px}.rbm-preview::before,.rbm-preview::after{content:"";position:absolute;left:15%;width:35%;height:3px;background:var(--teal);transform-origin:left center}.rbm-preview::before{top:23px;transform:rotate(16deg)}.rbm-preview::after{top:58px;background:var(--coral);transform:rotate(-18deg)}.page-header{padding:38px 0 24px;border-bottom:1px solid var(--line)}.page-header h1{max-width:800px;font-size:clamp(2rem,4.5vw,3.4rem)}.lesson-grid{display:grid;grid-template-columns:minmax(260px,0.72fr) minmax(0,1.7fr);gap:34px;padding:34px 0 45px}.controls{padding-right:28px;border-right:1px solid var(--line)}.controls p{color:var(--muted);font-size:.94rem}.controls>*+*{margin-top:22px}.control{display:block}.control span{display:flex;justify-content:space-between;gap:12px;font-size:.92rem;font-weight:780}output{color:var(--teal);font-variant-numeric:tabular-nums}input[type="range"]{width:100%;margin-top:8px;accent-color:var(--teal)}.button-row{display:grid;gap:8px}.button-row.two{grid-template-columns:repeat(2,minmax(0,1fr))}.action{min-height:43px;border:1px solid var(--line);border-radius:5px;background:var(--surface);color:var(--ink);font-weight:800}.action.primary{border-color:var(--deep-teal);background:var(--deep-teal);color:white}.action:hover{border-color:var(--teal);color:var(--teal)}.action.primary:hover{background:var(--teal);color:white}.action.selected{border-color:var(--teal);background:#e4ece8;color:var(--deep-teal)}.experiment>section{padding-bottom:29px;margin-bottom:29px;border-bottom:1px solid var(--line)}.experiment>section:last-child{border-bottom:0}.section-heading{display:flex;justify-content:space-between;align-items:flex-end;gap:14px}.section-heading p{margin:0;color:var(--muted);font-size:.84rem;text-align:right}.formula{padding:12px 14px;border-left:4px solid var(--gold);background:#fff8e9;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.9rem}.bars{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;align-items:end;min-height:240px;margin-top:20px}.bar{display:grid;grid-template-rows:1fr auto auto;gap:7px;height:230px;text-align:center}.bar-track{display:flex;align-items:end;height:175px;border-bottom:1px solid var(--line);background:repeating-linear-gradient(to top,transparent 0,transparent 42px,rgba(20,52,47,0.08) 43px)}.bar-fill{width:100%;min-height:3px;background:var(--teal);transition:height 170ms ease}.bar:nth-child(2) .bar-fill{background:var(--blue)}.bar:nth-child(3) .bar-fill{background:var(--gold)}.bar:nth-child(4) .bar-fill{background:var(--coral)}.bar-value{color:var(--deep-teal);font-size:.86rem;font-weight:850}.bar-label{color:var(--muted);font-size:.75rem;font-weight:750;line-height:1.2}.readout{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin-top:19px}.readout-item{padding-top:10px;border-top:4px solid var(--line)}.readout-item strong{display:block;color:var(--deep-teal);font-size:1.3rem}.readout-item span{color:var(--muted);font-size:.77rem;font-weight:750}.pattern-layout{display:grid;grid-template-columns:auto minmax(0,1fr);gap:24px;align-items:center;margin-top:20px}.spin-grid{display:grid;grid-template-columns:repeat(3,50px);gap:6px}.spin-cell{width:50px;height:50px;border:1px solid var(--line);border-radius:3px;background:#e8eeeb}.spin-cell.on{background:var(--deep-teal)}.pattern-copy{color:var(--muted)}.energy-trace{min-height:115px;display:flex;align-items:end;gap:5px;margin-top:18px;border-bottom:1px solid var(--line)}.trace-bar{flex:1;min-width:5px;background:var(--violet);opacity:.85}.sample-box{min-height:64px;margin-top:18px;padding:13px 14px;border-left:4px solid var(--gold);background:#fff8e9}.topic-footer{display:flex;justify-content:space-between;gap:12px;padding:20px 0 42px;border-top:1px solid var(--line)}.topic-footer a{color:var(--deep-teal);font-size:.9rem;font-weight:800;text-decoration:none}.topic-footer a:hover{text-decoration:underline}@media(max-width:820px){.site-nav{min-height:58px}.nav-links{gap:2px}.nav-link{padding:7px 6px;font-size:.77rem}.topic-grid{grid-template-columns:1fr}.topic-card{min-height:215px}.lesson-grid{grid-template-columns:1fr;gap:28px}.controls{padding:0 0 29px;border-right:0;border-bottom:1px solid var(--line)}}@media(max-width:520px){.shell{width:min(100% - 24px,1120px)}.site-nav{justify-content:center}.site-nav .brand{display:none}.brand{font-size:.8rem}.nav-link{font-size:.72rem}.page-header{padding-top:28px}.section-heading{display:block}.section-heading p{margin-top:8px;text-align:left}.bars{gap:7px}.bar{height:205px}.bar-track{height:150px}.readout{grid-template-columns:1fr}.pattern-layout{grid-template-columns:1fr}.spin-grid{grid-template-columns:repeat(3,1fr);width:100%}.spin-cell{width:100%;aspect-ratio:1;height:auto}.button-row.two{grid-template-columns:1fr}}