:root{--paper:#f7f8f3;--ink:#182e2b;--muted:#66756e;--line:#e1e7de;--green:#234c40;--mint:#e5eedc;--lime:#d5eea5;--orange:#d0744c;--white:#fff;--radius:22px;font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI",Arial,sans-serif;color:var(--ink);background:var(--paper);font-synthesis:none}*{box-sizing:border-box}body{margin:0}button,input{font:inherit}button,a,input{-webkit-tap-highlight-color:transparent}button,a{touch-action:manipulation}button{cursor:pointer}button{color:inherit}a{color:inherit;text-decoration:none}button:focus-visible,a:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid 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.button{flex:1}.secondary{background:#e8ecdf;color:var(--green)}#toast{position:fixed;bottom:28px;left:50%;transform:translate(-50%,20px);background:#183f35;color:white;padding:12px 20px;border-radius:13px;z-index:100;box-shadow:0 6px 30px #0002;opacity:0;pointer-events:none;transition:.2s;font-size:13px;max-width:90vw;min-width:230px;text-align:center}#toast.show{opacity:1;transform:translate(-50%,0)}.about-list{padding-left:20px;font-size:14px;line-height:1.9;color:var(--muted)}
@media(min-width:1250px){.lessons{grid-template-columns:repeat(4,minmax(0,1fr))}.hero{min-height:310px;padding:35px}.hero-art{right:10px;width:220px}.hero h2{font-size:40px}.home-grid{grid-template-columns:1.7fr 1fr}.lesson{padding:16px}.lesson h3{font-size:16px}}
@media(max-width:1000px){.sidebar{width:202px;padding:30px 19px}.workspace{margin-left:202px}.topbar{padding:0 28px}main{padding:30px 28px}.home-grid{grid-template-columns:1fr}.progress-card{display:none}.hero-art{right:18px}.hero h2{font-size:37px}.footer{margin-left:28px;margin-right:28px}.calculator-layout{grid-template-columns:1fr}}
@media(max-width:700px){.sidebar,.desktop-label{display:none}.workspace{margin-left:0}.mobile-brand{display:flex;font-size:14px}.brand-mark{width:36px;height:38px;font-size:24px;border-radius:11px}.brand-mark>span{font-size:17px;right:5px;bottom:7px}.brand>span:last-child>span{font-size:11px;letter-spacing:1px}.topbar{height:77px;padding:0 21px;background:var(--paper);border-bottom:0}.header-actions{gap:7px}.header-actions .icon-button{width:37px;height:37px}.header-actions svg{width:18px;height:18px}main{padding:17px 21px 23px}h1{font-size:30px;letter-spacing:-1.3px;margin:12px 0 9px}.eyebrow{font-size:10px;letter-spacing:1.3px}.intro{font-size:13px;line-height:1.6;margin-bottom:22px;max-width:330px}h2{font-size:21px}.hero{min-height:289px;padding:25px 24px;border-radius:22px}.hero h2{font-size:34px;margin:20px 0 12px;max-width:230px}.hero p{font-size:12px;max-width:170px;margin-bottom:19px;line-height:1.6}.hero .eyebrow{font-size:9px}.hero .button{font-size:12px;min-height:45px;padding:12px 15px}.hero-art{right:-16px;bottom:28px;width:158px;height:190px;transform:scale(.85);transform-origin:right bottom}.step.s1{right:123px}.step.s2{right:66px}.step.s3{right:9px}.coin{right:7px;top:-3px}.spark{left:12px;top:11px;font-size:26px}.section-head{margin-top:26px;margin-bottom:13px}.section-head .text-link{font-size:11px}.lessons{gap:12px}.lesson{padding:11px;border-radius:16px}.lesson-cover{height:99px;border-radius:10px;margin-bottom:12px}.lesson-cover svg{width:41px;height:41px}.cover-label{font-size:35px}.cover-caption{font-size:8px;left:10px;bottom:10px}.lesson-meta{font-size:9px;gap:4px;margin-bottom:7px}.lesson-meta svg{width:11px;height:11px}.lesson h3{font-size:14px;line-height:1.4;letter-spacing:-.25px;padding:0}.lesson p{font-size:11px;line-height:1.5;margin:8px 0 10px}.lesson-bottom{padding-top:3px;margin-top:2px}.lesson-bottom .text-link{font-size:10px;padding-left:0;gap:2px}.save-button{width:35px;height:40px}.save-button svg{width:17px;height:17px}.done{font-size:8px;gap:1px}.feature-row{grid-template-columns:1fr;gap:10px;margin-top:20px}.feature{padding:19px}.feature strong{font-size:13px}.feature small{font-size:11px}.footer{margin:0 21px 103px;padding-top:16px;font-size:9px}.footer span{font-size:9px}.bottom-nav{position:fixed;bottom:0;left:0;right:0;display:flex;justify-content:space-around;gap:2px;padding:9px 10px calc(9px + env(safe-area-inset-bottom));background:#ffffffed;backdrop-filter:blur(15px);border-top:1px solid var(--line);z-index:20}.bottom-nav .nav-item{flex:1;display:flex;flex-direction:column;gap:5px;font-size:10px;font-weight:550;margin:0;padding:8px 4px;border-radius:12px}.bottom-nav .nav-item.active{background:#edf2e5}.bottom-nav svg{width:21px;height:21px}.chips{gap:7px}.chip{font-size:11px;padding:10px 14px}.form-card,.result-card{padding:21px}.calculator-layout{gap:16px}.result-value{font-size:35px}.dialog-body{padding:22px}.dialog-body h2{font-size:26px}.dialog-body p{font-size:14px}dialog{width:100%;max-width:100%;max-height:93dvh;margin:auto 0 0;border-radius:23px 23px 0 0;padding-bottom:env(safe-area-inset-bottom)}.dialog-top{padding:14px 21px}#toast{bottom:100px}.source{overflow-wrap:anywhere}}
button:disabled{opacity:.55;cursor:default;filter:none}.lesson-main:hover h3{text-decoration:underline;text-decoration-thickness:1px;text-underline-offset:3px}.calc-info>svg{width:16px;height:16px;vertical-align:middle;margin-right:4px}
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