*{box-sizing:border-box}body{margin:0}html{scroll-behavior:smooth}.btl{--ink:#172a28;--cream:#f4f1e8;--gold:#d0ad67;background:var(--cream);color:var(--ink);font-family:Arial,Helvetica,sans-serif;line-height:1.6}.btl a{color:inherit}.btl-container{max-width:1200px;margin:auto;padding-left:32px;padding-right:32px}.btl-nav{max-width:1360px;margin:auto;display:flex;align-items:center;justify-content:space-between;padding:24px 40px;gap:30px;border-bottom:1px solid #17362c25}.btl-brand{display:flex;align-items:center;gap:14px;text-decoration:none;line-height:1.15;letter-spacing:.12em;font-size:13px;font-weight:800}.btl-brand img{width:58px;height:58px;object-fit:contain}.btl-nav nav{display:flex;flex-wrap:wrap;align-items:center;gap:28px;font-size:14px}.btl-nav nav a{text-decoration:none}.btl-nav .btl-publisher{border-left:1px solid #193a3340;padding-left:28px}.btl a:hover{text-decoration:underline;text-underline-offset:5px}.btl :focus-visible{outline:3px solid #8e5d14;outline-offset:5px}.btl-skip{position:absolute;top:-100px;left:12px;background:white;padding:12px;z-index:10}.btl-skip:focus{top:10px}.btl-hero{display:grid;grid-template-columns:1.2fr 1fr;align-items:center;gap:65px;padding-top:85px;padding-bottom:85px}.btl-kicker{font-size:11px;font-weight:800;letter-spacing:.19em;margin:0 0 22px;color:#486156}.btl h1{font:400 clamp(45px,5.1vw,72px)/1.05 Georgia,serif;letter-spacing:-.045em;margin:0 0 27px}.btl h1 em{font-weight:400;color:#526b4f}.btl h2{font:400 clamp(34px,3.4vw,48px)/1.12 Georgia,serif;letter-spacing:-.035em;margin:0 0 22px}.btl h3{line-height:1.25}.btl p{max-width:650px}.btl-lead{font-size:18px;color:#4b5b52;line-height:1.75}.btl-actions{display:flex;gap:24px;align-items:center;flex-wrap:wrap;margin-top:28px}.btl-button{display:inline-flex;gap:28px;align-items:center;justify-content:space-between;background:#1c3930;color:#fff!important;text-decoration:none;padding:17px 22px;font-size:13px;font-weight:700}.btl-button:hover{background:#2c4b3e}.btl-link{display:inline-block;font-weight:700;font-size:14px;text-decoration:none;border-bottom:1px solid #738775;padding-bottom:5px}.btl-motto{margin-top:40px;font-size:10px;font-weight:700;letter-spacing:.23em}.btl-workbook{background:#dce1d3;padding:36px 28px 20px;transform:rotate(1.5deg);box-shadow:13px 18px 0 #19362a0d}.btl-paper{background:#fffdf6;padding:35px 30px;box-shadow:0 10px 25px #172a2815;border-top:8px solid #244035;transform:rotate(-3deg)}.btl-small{font-size:12px;color:#54645a}.btl-paper .btl-small{font-size:9px;letter-spacing:.13em}.btl-paper h2{margin:35px 0 15px;font-size:43px}.btl-paper p{font-size:15px}.btl-paper ol{padding:12px 0;list-style:none;border-top:1px solid #293f2f40;margin-top:30px}.btl-paper li{padding:11px 0;border-bottom:1px solid #293f2f20;font-size:12px}.btl-paper li span{margin-right:14px;font-size:10px;color:#687d64}.btl-paper a{font-size:11px;font-weight:700;text-decoration:none}.btl-edition{display:block;font-size:8px;letter-spacing:.14em;margin-top:30px;text-align:center}.btl-band{background:#1d3930;color:#eeeade}.btl-band .btl-container{display:flex;justify-content:space-between;gap:20px;padding-top:22px;padding-bottom:22px;font-size:10px;letter-spacing:.16em}.btl-section{padding-top:85px;padding-bottom:85px}.btl-sectionhead{display:flex;justify-content:space-between;gap:60px;align-items:end;margin-bottom:45px}.btl-sectionhead>p{max-width:420px;color:#536155;margin:0 0 24px}.btl-modules{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid #243c2d40;border-bottom:1px solid #243c2d40}.btl-modules article{padding:30px 22px 28px;border-right:1px solid #243c2d30;display:flex;flex-direction:column}.btl-modules article:first-child{padding-left:0}.btl-modules article:last-child{border:0}.btl-num{color:#70816a;font:italic 24px Georgia}.btl-modules h3{font:400 25px/1.2 Georgia;letter-spacing:-.03em}.btl-modules p{font-size:14px;color:#546253;margin-top:0}.btl-modules a{font-size:11px;font-weight:700;margin-top:auto;padding-top:15px;text-decoration:none}.btl-lessons{max-width:800px;margin:55px auto 0}.btl-lessons h3{font:400 28px Georgia}.btl details{border-bottom:1px solid #20372a30;padding:18px 0}.btl summary{cursor:pointer;font-size:15px;font-weight:700}.btl details p{font-size:14px;color:#46594a}.btl-calculator-section{background:#e3e7dc;padding:80px 0}.btl-calculator-grid{display:grid;grid-template-columns:1fr 1.1fr;gap:80px;align-items:center}.btl-calc{padding:28px;background:#fdfbf5;border:1px solid #1d382a25}.btl-fields{display:grid;grid-template-columns:1fr 1fr;gap:16px}.btl-fields label{font-size:11px;font-weight:700}.btl-fields input{display:block;width:100%;background:transparent;border:1px solid #81907b;color:#192f25;padding:10px 12px;margin-top:6px;font:17px Arial;border-radius:0}.btl-result{padding-top:20px;margin-top:20px;border-top:1px solid #19362c30}.btl-result span{display:flex;justify-content:space-between;font-size:14px;gap:20px;margin:8px 0}.btl-result span strong{font-size:23px}.btl-result p{font-size:12px}.btl-reset{background:transparent;border:0;padding:5px 0;color:#284331;text-decoration:underline;cursor:pointer;font-size:12px}.btl-download-feature{display:grid;grid-template-columns:1fr 1fr;gap:90px;align-items:center}.btl-download-feature p{color:#4c5e4d}.btl-resource-list{border-top:1px solid #263c2933}.btl-resource-list span{display:block;padding:14px 0;border-bottom:1px solid #263c2933;font-size:14px}.btl-reading{background:#e7deca;display:flex;gap:55px;align-items:center;padding-top:45px;padding-bottom:45px}.btl-reading img{width:140px;max-height:210px;object-fit:contain;box-shadow:7px 9px 15px #24352920}.btl-reading h2{font-size:36px}.btl-reading p{font-size:14px}.btl-notes{padding-top:40px;padding-bottom:40px;font-size:12px;color:#566453}.btl-notes p{max-width:950px}.btl-footer{border-top:1px solid #20372a40;padding-top:32px;padding-bottom:40px;display:flex;justify-content:space-between;gap:30px}.btl-footer strong{font-size:12px;letter-spacing:.12em}.btl-footer p{font-size:12px}.btl-footer nav{display:flex;gap:25px;align-items:center;font-size:12px;flex-wrap:wrap}.btl-resource-hero{padding-top:80px;padding-bottom:55px}.btl-resource-download{display:grid;grid-template-columns:.8fr 1.2fr;gap:70px;align-items:center;padding-bottom:75px;border-bottom:1px solid #20372a40}.btl-resource-cover{background:#203b30;color:#f4eedf;aspect-ratio:.85;padding:40px;display:flex;flex-direction:column;justify-content:space-between;border-bottom:12px solid #c6aa76}.btl-resource-cover>span{font-size:11px;letter-spacing:.2em}.btl-resource-cover h2{font-size:44px;margin:30px 0}.btl-resource-cover p{font-size:9px;letter-spacing:.18em}.btl-resource-cover strong{font:italic 20px Georgia;color:#ddc38b}.btl-resource-download article p,.btl-resource-download li{font-size:15px;color:#4c5e4d}.btl-resource-download article .btl-small{font-size:12px}.btl-resource-download ul{padding-left:20px;margin-bottom:28px}@media(max-width:850px){.btl-hero{gap:35px;grid-template-columns:1fr 1fr;padding-top:60px}.btl-nav{padding:20px 24px}.btl-nav nav{gap:16px}.btl-nav .btl-publisher{padding-left:0;border:0}.btl-paper{padding:25px 20px}.btl-paper h2{font-size:34px}.btl-modules{grid-template-columns:1fr 1fr}.btl-modules article:nth-child(2){border-right:0}.btl-modules article:nth-child(3){padding-left:0}.btl-calculator-grid,.btl-download-feature{gap:35px}.btl-resource-download{gap:35px}.btl-resource-cover{padding:25px}.btl-resource-cover h2{font-size:34px}}@media(max-width:600px){.btl-container{padding-left:22px;padding-right:22px}.btl-nav{align-items:start;flex-direction:column;gap:18px}.btl-nav nav{font-size:12px;gap:20px}.btl-brand img{width:45px;height:45px}.btl-hero,.btl-calculator-grid,.btl-download-feature,.btl-resource-download{grid-template-columns:1fr}.btl-hero{padding-top:45px;padding-bottom:55px;gap:45px}.btl h1{font-size:46px}.btl-workbook{max-width:380px;margin:0 10px}.btl-band .btl-container{display:grid;grid-template-columns:1fr 1fr;gap:12px;font-size:9px}.btl-section{padding-top:55px;padding-bottom:55px}.btl-sectionhead{display:block;margin-bottom:30px}.btl-modules h3{font-size:23px}.btl-modules article{padding:25px 15px}.btl-modules p{font-size:13px}.btl-calculator-section{padding:55px 0}.btl-calc{padding:20px}.btl-reading{gap:24px}.btl-reading img{width:90px}.btl-reading h2{font-size:29px}.btl-footer{display:block}.btl-footer nav{margin-top:25px;gap:18px}.btl-resource-hero{padding-top:45px}.btl-resource-cover{max-width:360px;aspect-ratio:1;padding:32px}.btl-resource-cover h2{font-size:40px}.btl-resource-download{gap:35px;padding-bottom:45px}.btl-lead{font-size:16px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

.btl-header-logo{display:block;width:44px;height:44px;flex:0 0 44px;overflow:hidden}.btl-brand{flex-shrink:0;gap:12px}@media(max-width:600px){.btl-header-logo{width:38px;height:38px;flex-basis:38px}}
