@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;600;700&family=Manrope:wght@400;500;600;700;800&display=swap');
:root{--ink:#20283d;--teal:#3459e8;--orange:#da681e;--paper:#f5f7fb;--line:#e5e9f2;--purple:#8053bd;font-family:'DM Sans',sans-serif;color:var(--ink);background:var(--paper)}*{box-sizing:border-box}body{margin:0}button,input,select{font:inherit}button,summary,select{cursor:pointer}button,a,input,select,summary{touch-action:manipulation}button{border:1px solid var(--line);background:white;border-radius:9px;padding:11px 16px;color:var(--ink);min-height:44px}button:hover{background:#edf1fa}a{color:inherit}button:focus-visible,a:focus-visible,input:focus-visible,summary:focus-visible,select:focus-visible{outline:3px solid #819aff;outline-offset:3px}.dedication{background:var(--ink);color:#ffffff;text-align:center;padding:12px;font-size:13px}.dedication span{color:#dce5ff;margin:0 10px}header{max-width:1380px;margin:auto;padding:22px 40px;display:flex;align-items:center;justify-content:space-between;gap:20px}header>span{font-size:10px;letter-spacing:2px}.brand{font-size:32px;font-weight:800;letter-spacing:-2px;text-decoration:none}.brand span{color:var(--orange);margin-left:5px}.navwrap{position:sticky;top:0;z-index:10;background:#f5f7fb;border-block:1px solid var(--line);padding:10px max(24px,calc((100vw - 1300px)/2));display:flex;justify-content:space-between;align-items:center;gap:20px}#sticky-formula{color:var(--teal);font-size:15px;overflow-wrap:anywhere}nav{display:flex;gap:6px}nav a{font-size:13px;text-decoration:none;padding:12px;border-radius:8px}nav a:hover,nav a[aria-current]{background:#e7edff;color:#294bd3}main{max-width:1300px;margin:auto;padding:0 28px}.hero{display:flex;justify-content:space-between;align-items:center;gap:50px;padding:55px 0 35px}.eyebrow,.section-heading>span{font-size:11px;letter-spacing:1.5px;font-weight:700;color:#7b849a}h1{font-family:Georgia,serif;font-weight:400;font-size:clamp(44px,5.8vw,76px);line-height:1.06;letter-spacing:-2px;margin:20px 0}h1 em{color:var(--teal)}p{line-height:1.7}.hero>div>p:last-child{color:#7a8395}.hero-note{background:#eaf0ff;border-radius:100px 100px 16px 16px;padding:55px 32px 25px;max-width:300px;transform:rotate(2deg)}.hero-note span{font-size:10px;letter-spacing:2px;display:block;margin-bottom:20px}.hero-note b{font-family:Georgia,serif;font-size:22px;line-height:1.5}.hero-note p{font-size:13px}.section-heading{margin:42px 0 20px}h2{font-size:27px;letter-spacing:-.8px;margin:8px 0}h3{font-size:18px}section[id]{scroll-margin-top:90px}.workspace{display:grid;grid-template-columns:minmax(0,1fr) 310px;gap:22px}.card,.panel{background:white;border:1px solid var(--line);border-radius:16px;padding:24px}.plot-card{padding:0;overflow:hidden}.plot-title{display:flex;justify-content:space-between;padding:20px;border-bottom:1px solid var(--line);font-size:13px}#plot{display:block;width:100%;height:auto;min-height:250px}.scrubber{padding:12px 20px;display:flex;gap:12px;align-items:center}.scrubber label{font-size:12px;white-space:nowrap}.scrubber input{min-width:40px;flex:1}.term-card{background:#f3f6ff;padding:18px 22px;font-size:15px;line-height:1.7}.caption{font-size:12px;color:#7a8499}.plot-card>.caption{padding:0 20px}.controls label{display:block;font-size:12px;font-weight:600}.controls select{width:100%;margin:10px 0 18px}.param{margin:14px 0}.param-top{display:flex;justify-content:space-between;align-items:center;gap:10px}.param input[type=number]{width:90px}.param input[type=range]{width:100%;margin-top:10px}input[type=range]{accent-color:var(--teal);min-height:28px}input[type=number],select{border:1px solid #cdd5e6;border-radius:8px;background:#fafbfe;color:var(--ink);padding:10px;min-height:44px;max-width:100%}input[type=number]{width:100px}.formula{background:#f3f6ff;padding:14px;border-radius:10px;line-height:1.8;overflow-wrap:anywhere;font-weight:600}.panel{padding:0;margin:16px 0;overflow:hidden}summary{list-style:none;display:flex;justify-content:space-between;gap:16px;align-items:center;padding:20px;font-weight:600;font-size:15px}summary::-webkit-details-marker{display:none}summary>span{font-size:22px;font-weight:400}details[open]>summary>span{transform:rotate(45deg)}.panel-body{padding:0 22px 22px}.course{background:#f4f0ff;border:1px solid #dacdf5;border-left:4px solid #8053bd;border-radius:10px;margin:20px 0;color:#533582}.course summary{font-size:14px}.course>div{padding:0 20px 20px}.course p{font-size:14px}.course .formula{background:#ebe2fc}.twocol{display:grid;grid-template-columns:1fr 1fr;gap:25px}.inline{display:flex;gap:16px;align-items:end;flex-wrap:wrap;margin:18px 0}.inline label{display:flex;flex-direction:column;gap:7px;font-size:13px}.primary{background:var(--teal);color:white;border-color:var(--teal)}.primary:hover{background:#294bd3}.explanation{padding:18px;background:#f3f6ff;border-left:3px solid var(--teal);border-radius:8px;margin:18px 0;line-height:1.8;overflow-wrap:anywhere}.table-scroll{overflow:auto;max-height:350px;margin:15px 0}table{width:100%;border-collapse:collapse;font-size:13px;text-align:left}td,th{padding:13px 16px;border-bottom:1px solid var(--line);white-space:nowrap}th{background:#f3f6fc;position:sticky;top:0}.up{color:#3459e8}.down{color:#b45014}.sum-strip{display:flex;gap:4px;align-items:flex-end;height:90px;overflow:hidden}.sum-strip i{background:var(--teal);min-width:3px;flex:1;border-radius:3px 3px 0 0}.sum-strip i.neg{background:var(--orange)}#motif-svg{max-height:270px;width:100%}pre{background:#20283d;color:#e4eaff;padding:20px;border-radius:12px;font-size:13px;line-height:1.6;overflow:auto}.answers{display:grid;grid-template-columns:1fr 1fr;gap:12px}.answers button{text-align:left}.answers button.correct{background:#e7edff;border-color:#3459e8}.answers button.wrong{background:#fff0ec;border-color:#da681e}#feedback{min-height:45px}#checklist label{display:flex;gap:12px;padding:10px 0;font-size:14px}footer{padding:55px 0 30px;font-size:12px;color:#7a8499}footer b{color:var(--ink)}#limit-result{line-height:1.8}svg text{font-family:inherit}.point{cursor:pointer}.point:hover{stroke:var(--orange);stroke-width:4}@media(max-width:900px){.workspace{grid-template-columns:minmax(0,1fr) 270px}.hero-note{max-width:260px}.scrubber{flex-wrap:wrap}.scrubber input{min-width:100px}}@media(max-width:700px){header{padding:16px 18px}header>span{display:none}main{padding:0 16px}.hero{padding:28px 0 16px}.hero-note{display:none}h1{font-size:50px}.navwrap{padding:12px 16px;min-height:52px}nav{position:fixed;bottom:0;left:0;right:0;background:var(--paper);border-top:1px solid var(--line);display:grid;grid-template-columns:repeat(4,1fr);padding:7px 5px max(8px,env(safe-area-inset-bottom));gap:1px}nav a{font-size:11px;text-align:center;padding:13px 2px}body{padding-bottom:80px}.workspace,.twocol{grid-template-columns:1fr}.controls{padding:18px}.param{margin:10px 0}.section-heading{margin-top:32px}h2{font-size:24px}.card{padding:18px}.plot-card{padding:0}.panel-body{padding:0 14px 16px}summary{padding:18px 14px;font-size:14px}.course>div{padding:0 14px 16px}.scrubber{padding:10px;gap:8px}.scrubber label{font-size:11px}.scrubber input{min-width:40px}.scrubber button{padding:10px}.answers{grid-template-columns:1fr}#plot{min-height:220px}.inline{gap:12px}section[id]{scroll-margin-top:75px}.eyebrow{font-size:9px}.table-scroll{max-height:280px}}@media(prefers-reduced-motion:no-preference){html{scroll-behavior:smooth}}
@media(max-width:700px){#plot text{font-size:22px}#plot .point circle:last-of-type{r:6px}}

/* Shared visual identity with the Parabole atelier. */
.dedication{background:#3459e8;font-size:16px;font-weight:600;padding:14px 20px;line-height:1.5}header{max-width:1500px;padding:0 48px;height:88px;border-bottom:1px solid var(--line)}header>span{color:#7b849a;font-weight:700;letter-spacing:1.7px}.brand{font-family:Manrope,sans-serif;font-size:27px;font-weight:800;letter-spacing:-1px;display:flex;align-items:center;gap:10px}.brand span{order:-1;background:#3459e8;color:white;width:34px;height:36px;border-radius:10px;display:grid;place-items:center;font-size:26px;margin:0}main{max-width:1500px;padding:0 48px}.hero{padding:36px 0 24px;gap:28px}h1{font-family:Manrope,sans-serif;font-size:clamp(26px,2.7vw,38px);font-weight:800;line-height:1.25;letter-spacing:-1.4px;margin:12px 0}h1 em{font-style:normal;color:#3459e8}h2,h3{font-family:Manrope,sans-serif}h2{font-size:25px}.hero-note{transform:none;border-radius:12px;max-width:330px;padding:20px 24px}.hero-note span{margin-bottom:10px;color:#7180a2}.hero-note b{font-family:Manrope,sans-serif;font-size:16px}.hero-note p{margin-bottom:0}.card{box-shadow:0 8px 30px #24345b04}.navwrap{padding-inline:max(24px,calc((100vw - 1404px)/2))}summary{font-size:14px}.course{color:#473466}.course summary{color:#533582}.formula{font-family:Manrope,sans-serif}.hero>div>p:last-child{font-size:16px}@media(max-width:1000px){header{padding:0 24px}main{padding:0 24px}}@media(max-width:700px){header{height:72px;padding:0 18px}main{padding:0 16px}.hero{padding:25px 0 16px}h1{font-size:28px;letter-spacing:-.8px}.dedication{font-size:14px}.hero>div>p:last-child{font-size:14px}h2{font-size:23px}}