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@media(max-width:900px){.book-grid{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:760px){html{scroll-padding-top:75px}.site-header{height:68px}.header-inner{padding:0 20px;gap:20px}.brand strong{font-size:21px}.brand svg{width:27px;height:27px}.header-inner nav{gap:18px;font-size:12px}.header-inner nav a:nth-child(1){display:none}.account-link{font-size:11px;padding:9px 14px;min-height:36px;display:inline-flex;align-items:center}.account-link span{display:none}.nav-home:after{bottom:-23px}.page-width{width:calc(100% - 40px)}.opening{grid-template-columns:1fr;gap:27px;padding:37px 0 34px}.opening h1{font-size:30px;line-height:1.55}.mobile-break{display:inline}.opening-description{font-size:12px}.opening-search{max-width:100%}.opening-search form{padding-block:8px}.opening-search input{font-size:12px}.opening-search form button{padding:8px 19px}.search-suggestions{gap:12px;padding:11px 2px;font-size:10px}.section-heading{align-items:center;margin-bottom:20px}.section-heading h2{font-size:21px}.section-heading>a{font-size:10px}.section-heading>a span{margin-left:7px}.section-kicker{font-size:9px;letter-spacing:1px}.featured-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:15px}.featured-cover{height:140px}.featured-copy{padding:13px 14px 16px}.featured-copy h3{font-size:13px;min-height:45px;margin:6px 0 9px}.featured-copy small{font-size:9px}.featured-copy span:last-child{font-size:10px}.library{padding-top:38px}.library-layout{display:block;padding-top:20px}.library-filters{display:block}.library-filters h3,.filter-note{display:none}.filter-list{flex-direction:row;overflow:auto;white-space:nowrap;padding-bottom:6px;gap:4px;scrollbar-width:none}.filter-list button{font-size:11px;padding:7px 12px;white-space:nowrap;min-height:36px}.filter-list+ h3+ .filter-list{margin:3px 0 13px}.subject-filters{padding:9px 0 15px;gap:3px}.subject-filters button{font-size:10px;padding:5px 12px}.results-toolbar{padding:12px 0 20px;font-size:10px}.book-grid{grid-template-columns:repeat(3,minmax(0,1fr));gap:25px 16px}.book-card h3{font-size:14px;line-height:1.65;margin-top:11px}.book-meta{font-size:11px;margin-bottom:6px}.book-cover{box-shadow:2px 4px 9px #152a4210}.course-count{font-size:10px}.topic-grid{grid-template-columns:1fr;gap:12px}.topics{padding-top:43px}.topic-grid button{padding:22px;min-height:130px}.topic-number{position:absolute;right:22px;top:22px;font-size:26px}.topic-grid h3{margin:0 0 7px;font-size:16px}.topic-grid p{margin-bottom:16px;font-size:11px}.topic-arrow{font-size:10px}.learning-note{margin-top:40px;padding:27px;display:block}.learning-note h2{font-size:22px;line-height:1.6}.learning-note p{font-size:11px}.learning-note .primary-button{margin-top:22px}.help{padding-top:38px;padding-bottom:30px}.help h2{font-size:17px}.help summary{font-size:11px;min-height:48px;padding:16px 0}.help details p{font-size:11px}.site-footer{display:flex;flex-wrap:wrap;gap:10px 18px;padding:23px 0 28px;font-size:9px}.site-footer nav{margin-left:auto;gap:14px}.site-footer>span{border:0;padding-left:0;width:100%}.footer-brand{font-size:15px}.detail-page{padding-top:20px}.detail-hero{grid-template-columns:110px minmax(0,1fr);gap:23px;padding-bottom:25px}.detail-hero>.book-cover{width:110px}.detail-info h1{font-size:20px;line-height:1.6;margin:6px 0 12px}.detail-info .description{font-size:11px}.detail-badges{gap:5px;font-size:9px}.detail-actions{gap:9px;margin-top:18px}.detail-actions .primary-button,.detail-actions .secondary-button{padding:9px 12px;font-size:10px}.access-status{font-size:10px}.chapter-section{padding-top:27px}.chapter-section h2{font-size:19px}.chapter-row{padding:15px 3px;font-size:12px}.chapter-row .chapter-label{font-size:10px}.chapter-note{font-size:11px}.lesson-cover-list{grid-template-columns:repeat(2,1fr)}.breadcrumbs{font-size:10px;margin-bottom:22px}}
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@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important;animation:none!important}}
.cover-real img{object-fit:contain;background:#f6f3eb}.featured-cover img{object-fit:contain}

.collection-members{margin-top:36px}.collection-member{padding:18px 0;border-bottom:1px solid #e9edf2}.collection-member h3{font-size:15px;margin:0}.collection-member p{font-size:12px;color:#75818f}.collection-member a{display:inline-block;font-size:12px;margin:0 22px 8px 0;color:#3268cf}

.book-card h3{min-height:3.4em}
.book-foot{display:flex;align-items:center;justify-content:space-between;gap:10px}
.book-more{font-size:11px;color:#3268cf;white-space:nowrap}
@media(max-width:560px){.book-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:26px 16px}.book-card h3{font-size:14px;line-height:1.6;margin-top:11px}.book-meta{font-size:11px}.book-more{font-size:11px}.book-card .free-tag{font-size:10px}}

.support-contact{margin-top:28px;padding:26px 30px;background:#f5f8fc;border-radius:8px;display:flex;align-items:center;justify-content:space-between;gap:24px}
.support-contact h3{font-size:16px;font-weight:500;margin:0 0 7px}
.support-contact p{font-size:13px;line-height:1.8;color:#5f6b79;margin:0}
.support-contact p a{color:var(--blue);text-decoration:underline;text-underline-offset:3px}
.support-contact .primary-button{flex-shrink:0}
@media(max-width:640px){.support-contact{display:block;padding:22px}.support-contact .primary-button{margin-top:16px}}

.book-summary{font-size:11px;line-height:1.7;color:#5d6b7a;margin:0 0 9px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;min-height:38px}
@media(max-width:560px){.book-summary{font-size:12px;line-height:1.65;min-height:40px}}