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.derivation{display:grid;grid-template-columns:1fr 1.2fr .8fr;gap:38px;align-items:center;border-top:1px solid var(--line);padding-top:36px;margin-bottom:60px}.derivation-steps{border-left:5px solid var(--red);padding:22px 26px;background:#e9e4d9;font-size:23px;letter-spacing:-.03em}.derivation-steps p{margin:0 0 9px}.derivation-steps p:last-child{margin:0}.derivation-conclusion{font-size:20px;letter-spacing:-.02em;max-width:270px}.worked-interactive{display:grid;grid-template-columns:1fr 2fr;gap:35px;margin:36px 0 66px}.worked-intro>p{max-width:290px}.micro-label{font-size:9px;color:var(--muted);display:block;margin:32px 0 12px}.step-controls{display:flex;align-items:center;gap:15px;flex-wrap:wrap}.step-next{display:inline-flex;align-items:center;gap:27px;border:0;background:var(--red);color:var(--paper);padding:12px 16px;font-size:13px;font-weight:700}.step-next:hover{background:var(--ink)}.step-next:disabled{background:var(--ink);opacity:.5}.reset-steps{border:0;background:transparent;padding:10px 0;font-size:12px}.worked-board{background:var(--ink);color:var(--paper);padding:26px 30px;min-width:0}.board-top{display:flex;align-items:center;justify-content:space-between}.board-top strong{font-size:16px}.board-top>span{font-size:10px;letter-spacing:.15em;color:#b7b3aa}.term-steps{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));padding:0;list-style:none;margin:40px 0 20px;gap:9px}.term-steps li{display:flex;flex-direction:column;align-items:center;justify-content:center;border-top:2px solid #484742;padding:15px 0 20px;min-width:0}.term-steps li>span{font-size:16px;color:#c8c3b8}.term-steps li strong{font-size:clamp(26px,3.5vw,47px);line-height:1.5;letter-spacing:-.055em;visibility:hidden}.term-steps li small{font-size:10px;white-space:nowrap;visibility:hidden}.term-steps li.revealed{border-color:var(--red)}.term-steps li.revealed strong,.term-steps li.revealed small{visibility:visible}.term-steps li.revealed:last-child strong{color:#7995ff}#step-summary{font-size:13px;min-height:40px;max-width:470px;color:#d1cdc5}.show-all{border:0;background:none;padding:0;color:#f2ede2;text-decoration:underline;text-underline-offset:4px;font-size:11px}.worked-board button:focus-visible{outline-color:var(--paper)}.two-examples{display:grid;grid-template-columns:1fr 1fr;gap:60px}.two-examples>article{border-top:1px solid var(--ink);padding-top:27px}.two-examples>article>p{max-width:450px}.solution{margin:25px 0 22px;border:1px solid var(--ink);border-left:6px solid var(--red);padding:0 24px}.solution summary{padding:17px 0;font-weight:700;font-size:17px;display:flex;align-items:center;justify-content:space-between;cursor:pointer;list-style:none}.solution summary::-webkit-details-marker{display:none}.solution summary span{font-size:24px;font-weight:400;line-height:1;transition:transform .2s}.solution[open] summary span{transform:rotate(45deg)}.solution-maths{font-size:30px;line-height:1.35;letter-spacing:-.03em;padding:6px 0 5px}.solution-maths p{margin-bottom:22px}.indent-equals{display:block;margin-left:46px}.blue-solution{background:var(--blue);border-color:var(--blue);color:var(--paper)}.blue-solution summary:focus-visible{outline-color:var(--paper)}
.applications-section{padding:65px 0 66px;background:var(--ink);color:var(--paper)}.applications-intro{display:grid;grid-template-columns:1.15fr 1fr;column-gap:80px;align-items:end}.applications-intro .panel-title{grid-row:span 2;margin:0}.applications-intro h2{font-size:clamp(36px,4.2vw,59px)}.applications-intro p{font-size:18px;max-width:420px;margin-bottom:14px;color:#d5d1c8}.applications-intro p:last-child{font-size:14px;margin-bottom:0}.applications-grid{margin-top:55px;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:40px}.applications-grid article{border-top:1px solid #5a574f;padding-top:25px}.applications-grid h3{font-size:24px;margin:24px 0 17px}.applications-grid p{font-size:15px;max-width:330px;color:#d5d1c8;margin:0}.bar-symbol{display:flex;gap:6px;height:48px;align-items:flex-end}.bar-symbol i{width:12px;height:100%;background:#7892ff}.bar-symbol i:first-child{height:33%}.bar-symbol i:nth-child(2){height:66%}.decay-bars{transform:scaleX(-1);transform-origin:24px}.comparison-section{display:grid;grid-template-columns:1fr 1.6fr;gap:60px;padding-top:100px;padding-bottom:100px;align-items:start}.comparison-intro h2{font-size:clamp(29px,3vw,45px)}.comparison-intro p{max-width:320px;font-size:17px}.table-scroll{overflow:auto}table{width:100%;border-collapse:collapse;min-width:480px;line-height:1.4}th,td{padding:20px 17px;border-bottom:1px solid var(--line);text-align:left;font-size:14px}thead{background:var(--blue);color:var(--paper)}thead th{font-size:16px;padding:17px}tbody th{font-size:12px;width:20%}tbody tr:last-child th,tbody tr:last-child td{border-bottom:2px solid var(--ink)}table small{font-size:12px}
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.further-section{display:grid;grid-template-columns:1fr 1.6fr;gap:60px;padding-top:100px;padding-bottom:95px}.further-intro h2{font-size:clamp(35px,4vw,58px)}.further-accordion{border-top:2px solid var(--ink)}.further-accordion details{border-bottom:1px solid var(--line);padding:22px 0}.further-accordion summary{list-style:none;display:flex;align-items:center;gap:20px;font-size:19px;font-weight:700;color:var(--blue);cursor:pointer;line-height:1.2}.further-accordion summary::-webkit-details-marker{display:none}.further-accordion summary>span{font-size:11px;font-weight:400;color:var(--muted)}.further-accordion summary>i{margin-left:auto;font-size:27px;font-style:normal;transition:transform .2s}.further-accordion details[open] summary>i{transform:rotate(45deg)}.further-accordion details>p{font-size:16px;line-height:1.5;margin:18px 30px 0}.learn-more{padding-top:60px;padding-bottom:75px;display:grid;grid-template-columns:1.1fr 1fr;gap:100px;position:relative}.learn-more:before{content:"";position:absolute;left:var(--gutter);right:var(--gutter);top:0;height:3px;background:var(--ink)}.learn-more h2{font-size:clamp(48px,6vw,85px)}.closing-quote{font-size:20px;max-width:460px;margin:24px 0 30px;line-height:1.5;color:var(--muted)}.next-step-pending{display:inline-flex;align-items:center;justify-content:space-between;gap:40px;font-size:14px;font-weight:700;border:1px solid #b4afa4;background:transparent;padding:16px 20px;color:var(--muted)}.next-step-pending span{font-size:22px;line-height:1}.pending-note{font-size:11px;letter-spacing:.04em;margin-top:11px;color:var(--muted)}.resource-list{border-left:1px solid var(--line);padding-left:50px}.resource-list li{font-size:16px;margin-bottom:13px}.source-library{padding-top:55px;padding-bottom:65px;border-top:1px solid var(--line)}.source-library h2{font-size:29px;letter-spacing:-.035em}.source-library .eyebrow{margin-bottom:9px;color:var(--muted)}.poster-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:20px;margin-top:27px}.poster-card{border:0;padding:0;text-align:left;background:none;width:100%;min-width:0}.poster-card .poster-thumb{display:block;overflow:hidden;border:1px solid var(--line);padding:7px;transition:transform .2s,border-color .2s}.poster-card:hover .poster-thumb{transform:translateY(-4px);border-color:var(--ink)}.poster-card img{width:100%;height:auto;aspect-ratio:2100/1486;object-fit:contain}.poster-card>span:last-child{display:flex;gap:12px;justify-content:space-between;font-size:11px;font-weight:700;line-height:1.4;margin-top:12px}.poster-card b{font-weight:400;color:var(--red)}.site-footer{border-top:2px solid var(--ink);display:flex;align-items:center;justify-content:space-between;gap:20px;padding-top:27px;padding-bottom:32px}.footer-brand{font-size:20px;gap:0}.site-footer>span{font-size:9px;color:var(--muted);text-transform:uppercase;letter-spacing:.09em}.site-footer>a:last-child{font-size:11px;font-weight:700}
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