/* PDF storefront: extend the approved MathStandard identity. */
:root{scroll-padding-top:24px}.header{gap:24px}nav{gap:25px;font-size:14px}.brand .byline{font-size:13px}.brand-promise{font-size:12px}.hero-copy .eyebrow{font-size:14px}.hero .support{font-size:14px}.math-tag{font-size:12px}.hero{padding-block:58px 65px}.hero .lead{font-size:19px}.hero-actions .text-link{font-size:16px}.catalog .section-head{align-items:start}.section-head>p{font-size:16px;line-height:1.85}.catalog{padding-top:65px}.availability{display:flex;flex-direction:column;gap:5px;background:var(--pale);border-left:4px solid var(--blue);padding:18px 22px;margin:0 0 32px;color:var(--muted);font-size:15px}.availability strong{color:var(--navy);font-size:16px}.product-grid{display:grid;grid-template-columns:1fr 1fr;gap:28px}.product{display:grid;grid-template-columns:170px 1fr;gap:25px;padding:26px;border:1px solid var(--line);border-radius:12px;align-items:start;background:#fff}.cover-link{display:block;background:#f1f4fa;padding:12px;border-radius:6px}.cover-link img{display:block;width:100%;height:auto;box-shadow:0 5px 12px #13254c18;transition:transform .15s}.cover-link:hover img{transform:translateY(-3px)}.product-kind{font-size:13px;font-weight:600;letter-spacing:.4px;color:var(--blue);margin-bottom:12px}.product h3{font-size:21px;line-height:1.6;margin-bottom:13px}.product h3+p{font-size:16px;color:var(--muted)}.product-facts{padding-left:19px;color:var(--muted);font-size:14px;margin:16px 0}.product-facts li{margin-block:5px}.price-line{display:flex;flex-wrap:wrap;align-items:center;gap:12px;margin:22px 0 18px}.price{font:600 32px Arial,sans-serif;color:var(--blue)}.price small{font:400 14px 'Noto Sans Thai',sans-serif;color:var(--muted)}.price-note{font-size:12px;color:var(--muted)}.product .button{font-size:14px;min-height:46px;padding:11px 15px}.catalog-note{font-size:14px;color:var(--muted);margin-top:25px;line-height:1.9}.samples-section{padding-block:65px;background:var(--pale);border-block:1px solid var(--line)}.sample-grid{display:grid;grid-template-columns:1fr 1fr;gap:30px}.sample{display:grid;grid-template-columns:48% 1fr;align-items:center;gap:24px;background:white;border:1px solid var(--line);padding:24px;border-radius:10px}.sample>a{display:block}.sample img{display:block;width:100%;height:auto;border:1px solid #e3e7ed;box-shadow:0 4px 10px #13254c0d}.sample h3{font-size:21px;margin-bottom:12px}.sample p{font-size:16px;color:var(--muted);margin-bottom:20px}.sample .text-link{color:var(--blue);font-size:14px;text-decoration:underline;text-underline-offset:4px}.knowledge{display:grid;grid-template-columns:.8fr 1.3fr;gap:65px;margin-top:62px;padding-top:46px;border-top:1px solid #d3ddec}.knowledge>div>p:last-child{color:var(--muted);font-size:16px;margin-top:22px}.knowledge .practice-motto{font-size:17px}.knowledge details{padding:18px 0}.knowledge summary{font-size:17px}.knowledge summary span{display:block;font-size:13px;color:var(--blue);font-weight:500;margin-bottom:7px}.knowledge details p{font-size:16px;line-height:1.95}.teaching{display:grid;grid-template-columns:.8fr 1.3fr;gap:65px}.teaching .lead{font-size:18px;max-width:365px}.license-panel{border-top:3px solid var(--blue);background:var(--pale);padding:28px 32px}.license-panel h3{font-size:21px}.license-panel ul{padding-left:22px;margin:20px 0}.license-panel li{padding-left:3px;margin-block:13px;font-size:16px}.license-panel p{font-size:14px;color:var(--muted)}.roadmap-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:34px}.roadmap-grid article{border-top:1px solid var(--line);padding-top:25px}.roadmap-grid span{color:var(--blue);font:500 18px Arial,sans-serif;display:block;margin-bottom:18px}.roadmap-grid h3{font-size:22px;line-height:1.6;margin-bottom:14px}.roadmap-grid p{color:var(--muted);font-size:16px}.buy-section{background:#f0f4fb;padding:60px 0}.buy-steps{list-style:none;counter-reset:buy;display:grid;grid-template-columns:repeat(4,1fr);gap:30px;padding:0;margin:36px 0}.buy-steps li{counter-increment:buy}.buy-steps li::before{content:'0' counter(buy);display:block;font:600 26px Arial,sans-serif;color:var(--blue);margin-bottom:22px}.buy-steps h3{font-size:21px;margin-bottom:15px}.buy-steps p{font-size:16px;color:var(--muted)}.channel-status{border-top:1px solid #ced9ea;padding-top:27px;max-width:900px}.channel-status strong{font-size:19px}.channel-status p{color:var(--muted);margin:10px 0 18px;font-size:16px}.channel-status .text-link{color:var(--blue);text-decoration:underline;text-underline-offset:4px}.faq details p{font-size:16px}.footer p,.footer>.wrap>a:last-child{font-size:14px}.footer .brand .byline{font-size:13px}.topic-strip .wrap{flex-wrap:wrap}.button:focus-visible,.cover-link:focus-visible{outline-offset:4px}
@media(max-width:1100px){.product{grid-template-columns:1fr;padding:22px}.cover-link{width:180px;justify-self:center}.product h3{font-size:22px}.sample{gap:18px;padding:20px}.sample h3{font-size:19px}nav{gap:18px;font-size:14px}}
@media(max-width:850px){.header{flex-direction:column;align-items:flex-start;gap:20px}.header nav{width:100%;justify-content:space-between;flex-wrap:wrap;overflow:visible;white-space:normal;font-size:15px}.sample{grid-template-columns:1fr;align-items:start}.sample>a{width:100%;max-width:260px;justify-self:center}.knowledge,.teaching{gap:30px;grid-template-columns:1fr}.teaching .lead{max-width:none}.buy-steps{grid-template-columns:1fr 1fr;gap:30px}.roadmap-grid{gap:22px}.roadmap-grid h3{font-size:20px}}
@media(max-width:600px){.hero{padding-block:34px 45px}.hero h1{font-size:clamp(31px,9.8vw,43px);letter-spacing:-.7px}.hero .lead{font-size:18px}.hero .support{font-size:14px}.hero-copy .eyebrow{font-size:14px}.brand-promise{font-size:12px;letter-spacing:.9px}.header nav{gap:10px 20px;justify-content:flex-start;font-size:14px}.brand-lockup{width:245px}.hero-actions{gap:16px}.hero-actions .text-link{font-size:16px}.math-card{width:92%;padding:20px}.math-card-foot{font-size:14px}.equation{font-size:20px}.product-grid{grid-template-columns:1fr;gap:24px}.product{grid-template-columns:115px 1fr;gap:18px;padding:20px}.cover-link{width:100%;padding:8px}.product h3{font-size:20px}.product-body{min-width:0}.product-kind{font-size:12px}.product h3+p{font-size:16px}.product-facts{font-size:14px}.price-line{gap:10px}.price{font-size:30px}.product .button{width:100%;padding-inline:9px;font-size:14px}.sample-grid{gap:20px}.sample{padding:14px;gap:18px}.sample h3{font-size:18px}.sample p{font-size:15px}.sample .text-link{font-size:14px}.samples-section{padding-block:45px}.knowledge{margin-top:42px;padding-top:32px}.knowledge summary{font-size:16px}.license-panel{padding:22px}.roadmap-grid{grid-template-columns:1fr;gap:23px}.roadmap-grid article{padding-top:20px}.roadmap-grid span{margin-bottom:10px}.roadmap-grid h3{margin-bottom:8px}.buy-section{padding-block:45px}.buy-steps{gap:24px}.buy-steps h3{font-size:19px}.buy-steps p{font-size:15px}.catalog{padding-top:45px}.availability{padding:16px;font-size:14px}.footer .brand-lockup{width:220px}.footer p{display:block}}
@media(max-width:380px){.product{grid-template-columns:1fr}.cover-link{width:160px}.sample-grid{grid-template-columns:1fr}.sample{grid-template-columns:40% 1fr;gap:17px}.buy-steps{grid-template-columns:1fr}.hero h1{font-size:32px}.brand-promise{font-size:11px;letter-spacing:.7px}.math-card-foot{flex-wrap:wrap}.topic-strip .wrap{font-size:14px}.header nav{font-size:14px}.hero-copy .eyebrow{font-size:14px}}
@media(prefers-reduced-motion:reduce){.cover-link img{transition:none}}
@media print{.header nav,.hero-actions,.buy-section,.footer{display:none}.hero{padding:20px 0}.math-card{transform:none}.product,.sample,.license-panel{break-inside:avoid}.section,.samples-section{padding-block:24px}.wrap{width:100%}}
@media(max-width:600px){.product{grid-template-columns:1fr}.cover-link{width:160px}.sample-grid{grid-template-columns:1fr}.sample{grid-template-columns:40% 1fr;gap:20px;padding:20px}.sample h3{font-size:20px}}
/* Think, Practice, Repeat: the brand's learning philosophy. */
.learning-section{padding-block:62px;background:var(--pale);border-bottom:1px solid var(--line)}.learning-intro{max-width:920px}.learning-intro h2{font:600 clamp(30px,4.2vw,52px)/1.35 Arial,sans-serif;letter-spacing:-1.2px;color:var(--blue)}.learning-intro h2 span{color:#778aaf}.learning-subtitle{font-size:20px;line-height:1.9;margin-top:20px;color:var(--navy)}.learning-pillars{display:grid;grid-template-columns:repeat(3,1fr);gap:38px;margin-top:40px}.learning-pillars article{border-top:2px solid #cbd6ea;padding-top:24px}.pillar-index{font:500 14px Arial,sans-serif;color:var(--muted);display:block;margin-bottom:15px}.learning-pillars h3{font:600 29px/1.2 Arial,sans-serif;color:var(--blue);margin:0 0 18px}.learning-pillars h4{font-size:19px;line-height:1.65;margin:0 0 12px;font-weight:600}.learning-pillars p{font-size:16px;line-height:1.95;color:var(--muted)}.learning-principle{margin-top:36px;border-left:4px solid var(--blue);padding:5px 0 5px 23px;font-size:18px;line-height:1.95;max-width:980px}.learners{display:grid;grid-template-columns:.8fr 1.3fr;gap:65px;border-top:1px solid var(--line)}.learners .lead{font-size:18px}.learner-guidance article{border-bottom:1px solid var(--line);padding:22px 0}.learner-guidance article:first-child{padding-top:0}.learner-guidance h3{font-size:21px;line-height:1.65;margin-bottom:14px}.learner-guidance p{font-size:16px;line-height:1.95;color:var(--muted)}.teaching{padding-top:20px}#samples{scroll-margin-top:28px}
@media(max-width:1000px){.header nav{gap:18px;font-size:14px}.learning-pillars{gap:26px}.learning-pillars h4{font-size:18px}}
@media(max-width:850px){.learners{grid-template-columns:1fr;gap:30px}.learning-pillars{grid-template-columns:1fr;gap:26px}.learning-pillars article{padding-top:23px}.learning-pillars h3{font-size:28px;margin-bottom:13px}.learning-pillars h4{font-size:20px}.learning-intro h2{font-size:clamp(28px,5.3vw,43px);letter-spacing:-.6px}.learning-principle{font-size:17px}.learning-subtitle{font-size:18px}}
@media(max-width:600px){.learning-section{padding-block:42px}.learning-intro h2{font-size:clamp(25px,7.2vw,39px);line-height:1.55}.learning-subtitle{font-size:18px}.learning-pillars{margin-top:27px}.learning-principle{padding-left:18px;margin-top:28px}.learner-guidance h3{font-size:20px}.teaching{padding-top:12px}.header nav{gap:12px 20px}}
@media print{.learning-section{padding-block:25px}.learning-pillars article,.learner-guidance article{break-inside:avoid}}
.about-section#approach{display:block}