/* Subject etchings belong to the paper behind the real covers. */
.product-art.math-art{background-color:#edf3f8;background-image:radial-gradient(#6b9fc21a .6px,transparent .6px);background-size:5px 5px}
.product-art.ro-art{background-color:#f2f1eb;background-image:repeating-linear-gradient(0deg,transparent 0 25px,#b4a7870b 25px 26px)}
.product-art.bio-art{background-color:#edf3ef;background-image:radial-gradient(#658b6a12 .65px,transparent .65px);background-size:6px 6px}
.product-art:before{opacity:.22}
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.product-art.ro-art img.subject-texture{opacity:.23}
.product-art.bio-art img.subject-texture{opacity:.25}
.product-art:hover img.subject-texture{opacity:.34}
.product-art img.catalogue-cover{position:relative;z-index:1}
.product-art .edition{z-index:2}

/* An editorial explanation of what the books help a pupil do. */
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.value-story>.container{position:relative}
.value-intro{display:grid;grid-template-columns:1.25fr .8fr;gap:70px;align-items:end;margin-bottom:43px}
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.value-intro-copy{padding-bottom:3px}
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.value-topics{display:flex;flex-wrap:wrap;gap:10px;align-items:center;font-size:7px;font-weight:800;letter-spacing:1.1px;color:#40657c}
.value-topics i{font-style:normal;color:#9eb5bf;font-weight:400}
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.value-chapter{font-size:7px;letter-spacing:1.8px;font-weight:800;color:#80b9c9}
.value-lead h3{font-family:Manrope,sans-serif;font-size:26px;line-height:1.24;letter-spacing:-1.1px;font-weight:800;color:#eff9ff;margin:20px 0 13px}
.value-lead>p{font-size:11px;line-height:1.9;color:#a1bdce;margin:0;max-width:310px}
.value-paper-stack{position:relative;margin:31px 2px 19px;flex:1;display:flex;align-items:center;min-height:240px}
.value-paper-stack:before{content:"";position:absolute;inset:8px 2px 1px 1px;background:#80b2c8;border:1px solid #a3c7d6;border-radius:6px;transform:rotate(3.4deg);opacity:.6}
.value-paper{position:relative;width:100%;padding:21px 20px 17px;border:1px solid #d4e2e7;border-radius:6px;background:repeating-linear-gradient(0deg,transparent,transparent 23px,#85a9ce0d 23px,#85a9ce0d 24px),#fbfcf8;color:#204061;transform:rotate(-3.4deg);box-shadow:0 15px 25px #0003}
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.value-example-top{display:grid;grid-template-columns:1fr 94px;gap:12px;align-items:center}
.value-paper small{display:block;font-size:6px;letter-spacing:1.5px;color:#7893a7;font-family:Manrope,sans-serif;font-weight:800}
.value-formula{display:block;font-family:Georgia,'Times New Roman',serif;font-size:20px;line-height:1.65;font-weight:400;letter-spacing:-.5px;margin-top:7px;white-space:nowrap}
.value-area{height:94px;width:94px;overflow:visible;fill:none;stroke:#6f9fb8;stroke-width:1;stroke-linejoin:round}
.value-area text{font-family:Georgia,serif;font-style:italic;font-size:15px;fill:#466c85;stroke:none;text-anchor:middle}
.value-example{border-top:1px solid #dce7eb;margin-top:17px;padding-top:14px}
.value-example strong{display:block;font-family:Georgia,serif;font-size:15px;font-weight:400;margin-top:7px;color:#315574;white-space:nowrap}
.value-example em{font-style:normal;font-weight:700;color:#247a7d;background:#9eddd43d;padding:0 3px}
.value-paper-note{display:block;margin-top:13px;font-size:6px;color:#93a9b7;letter-spacing:.3px}
.value-aha{position:absolute;right:-9px;top:-21px;color:#98dfd5;transform:rotate(8deg);font:italic 17px Georgia,serif;z-index:2}
.value-aha svg{width:58px;height:23px;fill:none;stroke:#98dfd5;stroke-width:1.4;display:block;margin-left:16px;margin-top:4px}
.value-lead-foot{display:flex;align-items:center;gap:9px;color:#8bb5c5;font-size:6px;font-weight:800;letter-spacing:1.1px;margin-top:5px}
.value-lead-foot svg{width:19px;height:8px;stroke:#5e96aa;fill:none;stroke-width:1}
.value-feature{position:relative;min-width:0;border:1px solid #dce6eb;border-radius:16px;padding:26px 25px 22px;background:#fff;overflow:hidden;transition:transform .25s,box-shadow .25s,border-color .25s;display:flex;flex-direction:column}
.value-feature:after{content:"";position:absolute;right:-36px;top:-36px;width:104px;height:104px;border:1px solid #7ca8bb12;border-radius:50%;box-shadow:0 0 0 23px #7ca8bb05;pointer-events:none}
.value-feature-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:18px;gap:12px}
.value-feature-top>span{font-size:7px;letter-spacing:1.2px;font-weight:800;color:#7491a8;white-space:nowrap}
.value-feature-top svg{height:33px;width:33px;flex:none;fill:none;stroke:#4b8ab6;stroke-width:1.4;stroke-linecap:round;stroke-linejoin:round}
.value-feature h3{font-family:Manrope,sans-serif;font-size:22px;letter-spacing:-.8px;line-height:1.25;font-weight:800;color:#193247;margin:0 0 13px}
.value-feature p{color:#7c90a1;font-size:12px;line-height:1.85;margin:0;max-width:290px}
.feature-visual{background:#f2f9f7;border-color:#d4e6e1}.feature-visual .value-feature-top svg{stroke:#41928e}.feature-visual .value-feature-top>span{color:#65958e}
.feature-examples{background:#f9f7f0;border-color:#e7e3d6}.feature-examples .value-feature-top svg{stroke:#a39a73}.feature-examples .value-feature-top>span{color:#a0987f}
.feature-return{background:#f0f5f9}.feature-return .value-feature-top svg{stroke:#6785a4}
.value-mini-index{display:flex;align-items:center;gap:7px;margin-top:auto;padding-top:19px;color:#7b9bb6;font-size:7px;font-weight:800;opacity:.65}
.value-mini-index span{border:1px solid #c3d8e7;border-radius:3px;padding:4px 5px;background:#f4f8fb}.value-mini-index i{height:1px;width:23px;background:#c6dce9}
.value-mini-flow{display:flex;gap:0;align-items:center;margin-top:auto;padding-top:22px;opacity:.7}.value-mini-flow span{height:14px;width:37px;background:#cce8df;border:1px solid #9bcbc0;border-radius:4px}.value-mini-flow i{height:1px;width:25px;background:#94c7bd}.value-mini-flow span:nth-of-type(2){background:#8fc8bc}
.value-mini-steps{display:flex;align-items:center;gap:10px;margin-top:auto;padding-top:20px;font:italic 11px Georgia,serif;color:#9b936f}.value-mini-steps i{font-style:normal;font-size:12px;opacity:.6}
.value-bookmark{margin-top:auto;padding-top:22px;font-size:6px;letter-spacing:1.3px;font-weight:800;color:#7191ac;display:flex;gap:8px;align-items:center}.value-bookmark:before{content:"";width:6px;height:9px;background:#a3bdcf;clip-path:polygon(0 0,100% 0,100% 100%,50% 72%,0 100%)}
.value-bottom{display:flex;align-items:center;justify-content:space-between;gap:35px;border-top:1px solid #dae6eb;margin-top:33px;padding-top:28px}
.value-bottom-copy{display:flex;gap:18px;align-items:center}
.value-bottom-mark{font-family:Manrope,sans-serif;font-weight:800;font-size:29px;line-height:1;color:#366f92;border:1px solid #c5dbe5;background:#edf4f6;border-radius:10px;width:48px;height:48px;display:grid;place-items:center;flex:none}
.value-bottom-copy strong{font-size:15px;font-weight:800;letter-spacing:-.3px;color:#26465e}.value-bottom-copy p{font-size:10px;line-height:1.7;color:#8097a9;margin:6px 0 0}
.value-bottom .btn{flex-shrink:0;font-size:11px;padding:16px 20px}
@media(hover:hover) and (pointer:fine){.value-feature:hover{transform:translateY(-4px);border-color:#b9d3e0;box-shadow:0 14px 32px #2145630a}}
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@media(max-width:960px){.value-story{padding:87px 0 76px}.value-intro{grid-template-columns:1fr;gap:25px}.value-story h2{font-size:51px;max-width:650px}.value-intro-copy>p{max-width:640px;margin-bottom:15px}.value-intro-label{margin-bottom:11px}.value-grid{grid-template-columns:1fr 1fr;grid-template-rows:auto}.value-lead{grid-column:1/-1;grid-row:auto;display:grid;grid-template-columns:1fr 1fr;column-gap:38px;padding:31px}.value-lead .value-chapter{grid-column:1;align-self:end}.value-lead h3{grid-column:1;margin-top:17px;font-size:29px;align-self:start}.value-lead>p{grid-column:1;font-size:12px;margin-top:-3px;align-self:start}.value-paper-stack{grid-column:2;grid-row:1/5;margin:8px 7px 8px 0;min-height:260px}.value-example-top{grid-template-columns:1fr 94px;gap:12px}.value-area{height:94px;width:94px}.value-formula{font-size:21px}.value-paper{padding:23px 22px 18px}.value-example strong{font-size:15px}.value-lead-foot{grid-column:1;align-self:end;margin-top:25px}.value-feature{min-height:233px;padding:27px 25px}.value-feature h3{font-size:24px}.value-feature-top>span{font-size:7px;letter-spacing:1.1px}.value-feature-top svg{width:33px;height:33px}.value-feature p{font-size:12px;max-width:340px}.value-intro{margin-bottom:32px}.value-bottom{gap:22px}.value-bottom-copy strong{font-size:14px}.value-bottom-copy p{max-width:360px}.value-bottom-mark{display:none}}
@media(max-width:680px){.value-story{padding:68px 0 62px}.value-story .eyebrow{font-size:9px;margin-bottom:20px}.value-story h2{font-size:clamp(30px,7.7vw,45px);letter-spacing:-1.55px;line-height:1.18}.value-intro{gap:24px;margin-bottom:27px}.value-intro-copy>p{font-size:12px;line-height:1.9}.value-intro-label{font-size:7px}.value-topics{font-size:6px;gap:9px;letter-spacing:1px}.value-grid{grid-template-columns:1fr;gap:13px}.value-lead{display:flex;grid-column:auto;padding:28px 26px 23px;border-radius:16px}.value-lead h3{font-size:28px;letter-spacing:-1.1px;margin:18px 0 13px}.value-lead>p{font-size:11px;margin:0;max-width:350px}.value-paper-stack{margin:30px 2px 20px;min-height:248px;width:100%;max-width:360px;align-self:center}.value-paper{padding:21px 19px 17px}.value-example-top{grid-template-columns:1fr 93px;gap:10px}.value-area{width:93px;height:93px}.value-formula{font-size:21px}.value-example strong{font-size:15px}.value-aha{right:-7px;font-size:17px;top:-22px}.value-lead-foot{align-self:auto;margin-top:0;font-size:6px;gap:10px}.value-feature{padding:25px 25px 23px;min-height:218px;border-radius:14px}.value-feature-top{margin-bottom:15px}.value-feature-top svg{width:33px;height:33px}.value-feature h3{font-size:25px;letter-spacing:-.8px;margin-bottom:12px}.value-feature p{font-size:12px;line-height:1.85;max-width:440px}.value-mini-index,.value-mini-flow,.value-mini-steps,.value-bookmark{padding-top:19px}.value-bottom{display:block;margin-top:26px;padding-top:23px}.value-bottom-copy strong{font-size:16px;line-height:1.5;letter-spacing:-.4px}.value-bottom-copy p{font-size:11px;line-height:1.8;max-width:360px}.value-bottom .btn{margin-top:19px;font-size:11px;padding:15px 18px}.product-art img.subject-texture{opacity:.23}}
@media(max-width:370px){.value-story h2{font-size:28px;letter-spacing:-1.45px}.value-lead{padding:25px 21px 22px}.value-lead h3{font-size:25px}.value-formula{font-size:18px}.value-example-top{grid-template-columns:1fr 75px;gap:7px}.value-area{width:75px;height:75px}.value-example strong{font-size:12px}.value-paper{padding:19px 16px 15px}.value-feature{padding:24px 22px}.value-feature h3{font-size:23px}.value-topics{font-size:5.5px;gap:7px}}
@media(prefers-reduced-motion:reduce){.value-feature,.product-art img.subject-texture{transition:none!important}}