@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;600;700&family=Manrope:wght@400;600;700;800&display=swap');
:root{--ink:#172f50;--blue:#377396;--pale:#eaf4f9;--coral:#f28d7b;--gold:#f5d795}*{box-sizing:border-box}body{margin:0;background:#fafbf9;color:var(--ink);font-family:'DM Sans',Arial,sans-serif;line-height:1.6}h1,h2,h3{font-family:Manrope,Arial,sans-serif;line-height:1.18}a{color:inherit;text-underline-offset:4px}button,input,select{font:inherit;color:inherit}button,select{cursor:pointer}button,a,input,select,summary{touch-action:manipulation}button{border:1px solid #b4c9d6;border-radius:30px;background:white;padding:11px 20px;font-weight:700;min-height:46px}button:disabled{opacity:.45;cursor:default}button.primary{background:var(--ink);color:white;border-color:var(--ink)}button.quiet{background:transparent;border-color:transparent;text-decoration:underline}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible,[tabindex]:focus-visible{outline:3px solid #bb533e;outline-offset:4px}.skip{position:absolute;top:-100px;left:16px;background:white;padding:12px;z-index:20}.skip:focus{top:10px}header{display:flex;align-items:center;gap:32px;justify-content:space-between;max-width:1440px;margin:auto;padding:23px 4%;border-bottom:1px solid #d7e3e8}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;font-weight:800;font-size:22px;line-height:1.25}.brand img{width:43px}.brand small{display:block;font-size:10px;letter-spacing:.04em;font-weight:500;margin-top:3px}nav{display:flex;gap:4px;flex-wrap:wrap}nav a{padding:9px 16px;text-decoration:none;font-size:14px;font-weight:700;border-radius:30px}nav a[aria-current]{background:var(--pale)}.parent-link{font-size:13px}main{max-width:1200px;margin:auto;padding:0 38px}.intro{display:flex;justify-content:space-between;align-items:center;padding:62px 0 45px;gap:40px}.eyebrow{text-transform:uppercase;letter-spacing:.15em;font-size:11px;font-weight:700;margin:0 0 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#d7e3e8}[hidden]{display:none!important}@media(max-width:800px){header{flex-wrap:wrap;gap:15px}.parent-link{margin-left:auto}header nav{order:3;width:100%;justify-content:center}.intro-mark{display:none}.intro{padding:35px 0 25px}main{padding:0 20px}.workspace{padding:22px}.activity-heading{align-items:stretch;flex-direction:column;gap:18px}.mode-label{min-width:0}.preset-label{margin:8px 0 0;width:100%}.conversation{grid-template-columns:1fr;gap:15px}.grown-up{grid-template-columns:1fr;gap:0}.grown-up h2{max-width:350px}.path-stage{padding:16px}.strategy-row{align-items:start;flex-direction:column;gap:3px}.strategy-row p{margin:5px 0}.strategy-row select{width:100%}.strategy-row label{width:100%}.equation-row{align-items:start}.equation-row h3{font-size:23px}footer{padding:20px;flex-wrap:wrap}}@media(max-width:380px){main{padding:0 12px}.workspace{padding:16px}header{padding:16px}.brand{font-size:20px}.parent-link{font-size:11px}nav a{padding:9px 11px;font-size:12px}input{width:96px}.example-controls{gap:8px}.example-controls button{width:100%}.equation-row{flex-direction:column;gap:5px}.play-controls button{flex:1 1 40%;padding:10px}.jump-record ol{columns:1}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}