:root{--navy:#102f4a;--navy-2:#0a2238;--blue:#286da8;--sky:#eaf4fa;--gold:#e6a436;--ink:#182733;--muted:#667782;--paper:#f5f7f5;--white:#fff;--border:#dce4e7;--serif:'Libre Caslon Text',Georgia,serif;--sans:'DM Sans',Arial,sans-serif;--shadow:0 18px 50px rgba(16,47,74,.1);--radius:18px}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{font-family:var(--sans);color:var(--ink);background:#fff;line-height:1.65;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}img{max-width:100%;height:auto}.skip-link{position:absolute;left:1rem;top:-5rem;z-index:9999;background:#fff;padding:.7rem 1rem;border-radius:.5rem;box-shadow:var(--shadow)}.skip-link:focus{top:1rem}.container{--bs-gutter-x:2rem;max-width:1320px}.utility-bar{background:var(--navy-2);color:#dce9f2}.utility-bar a{transition:color .2s}.utility-bar a:hover{color:#fff}.nav-shell{background:#fff;position:relative;z-index:1030}.navbar-brand img{width:285px}.navbar .nav-link{font-weight:600;font-size:.94rem;color:#314657!important;padding:.65rem .8rem!important;position:relative}.navbar .nav-link:after:not(.dropdown-toggle){display:none}.navbar .nav-link.active,.navbar .nav-link:hover{color:var(--blue)!important}.navbar .nav-link.active:before{content:"";position:absolute;height:2px;left:.8rem;right:.8rem;bottom:.2rem;background:var(--gold)}.nav-icon{width:42px;height:42px;border:1px solid var(--border);border-radius:50%;display:grid;place-items:center;color:var(--navy);transition:.2s}.nav-icon:hover{background:var(--navy);color:#fff;border-color:var(--navy)}.cart-link{position:relative}.cart-link span{position:absolute;right:-3px;top:-5px;background:var(--gold);color:var(--navy-2);font-size:.65rem;font-weight:800;width:18px;height:18px;display:grid;place-items:center;border-radius:50%;border:2px solid #fff}.navbar-toggler{border:0;color:var(--navy);font-size:1.75rem;padding:.1rem .35rem}.navbar-toggler:focus{box-shadow:0 0 0 3px rgba(40,109,168,.2)}.announcement-bar{font-size:.82rem;background:#eaf3f8;color:#365164;border-top:1px solid #dce9ef}.announcement-label{color:var(--navy);font-weight:700;white-space:nowrap}.announcement-label i{color:var(--gold)}.offcanvas{--bs-offcanvas-width:330px}.mobile-nav a,.mobile-account a{display:flex;padding:.85rem 0;font-weight:600;border-bottom:1px solid var(--border)}.mobile-nav a.active{color:var(--blue)}
.hero-section{position:relative;overflow:hidden;background:var(--navy-2);color:#fff}.hero-backdrop{position:absolute;inset:0;background:linear-gradient(90deg,rgba(7,30,49,.98) 0%,rgba(10,38,61,.91) 42%,rgba(10,34,56,.3) 75%,rgba(10,34,56,.12)),url('../images/hero-library.jpg') center/cover no-repeat;transform:scale(1.01)}.hero-section:after{content:"";position:absolute;width:430px;height:430px;border:1px solid rgba(255,255,255,.12);border-radius:50%;right:-140px;top:-180px}.min-vh-hero{min-height:570px}.hero-section h1{font:700 clamp(2.7rem,5vw,5.25rem)/1.03 var(--serif);letter-spacing:-.045em;margin:1.25rem 0 1.2rem}.hero-section h1 em{font-weight:400;color:#f4c36e}.hero-lead{max-width:650px;color:#d7e4eb;font-size:1.15rem;margin-bottom:2rem}.eyebrow{display:inline-flex;align-items:center;color:var(--blue);font-size:.78rem;font-weight:800;letter-spacing:.13em;text-transform:uppercase}.eyebrow.light{color:#f4c36e}.hero-search{display:flex;align-items:center;background:#fff;border-radius:14px;padding:.45rem;max-width:680px;box-shadow:0 18px 45px rgba(0,0,0,.2)}.hero-search>i{color:#82919a;margin-left:.75rem}.hero-search input{min-width:0;flex:1;border:0;outline:0;padding:.85rem;color:var(--ink)}.hero-search button,.newsletter-form button{border:0;border-radius:10px;background:var(--gold);color:#172c3b;font-weight:800;padding:.85rem 1.55rem;transition:.2s}.hero-search button:hover,.newsletter-form button:hover{background:#f0b753;transform:translateY(-1px)}.popular-searches{display:flex;flex-wrap:wrap;gap:.6rem 1rem;font-size:.8rem;margin-top:1.1rem;color:#b9cbd6}.popular-searches span{font-weight:700;color:#fff}.popular-searches a{text-decoration:underline;text-underline-offset:3px}.benefit-strip{box-shadow:0 8px 30px rgba(16,47,74,.08);position:relative;z-index:2}.benefit{display:flex;align-items:center;gap:.8rem;padding:1.3rem;border-right:1px solid var(--border)}.benefit:last-child{border-right:0}.benefit>i{color:var(--blue);font-size:1.5rem}.benefit strong,.benefit span{display:block}.benefit strong{font-size:.88rem}.benefit span{font-size:.73rem;color:var(--muted)}
.section-space{padding:6.5rem 0}.bg-paper{background:var(--paper)}.section-heading{margin-bottom:2.5rem;max-width:700px}.section-heading h2,.publisher-section h2{font:700 clamp(2rem,3.5vw,3.25rem)/1.16 var(--serif);letter-spacing:-.035em;margin:.55rem 0 0}.section-heading p{color:var(--muted);margin-top:1rem}.text-link{display:inline-flex;align-items:center;gap:.45rem;color:var(--blue);font-weight:700;white-space:nowrap}.text-link i{transition:transform .2s}.text-link:hover i{transform:translateX(4px)}.subject-card{position:relative;display:flex;flex-direction:column;min-height:190px;padding:1.5rem;border:1px solid var(--border);border-radius:var(--radius);background:#fff;transition:.25s}.subject-card:hover{transform:translateY(-5px);border-color:#b5ccda;box-shadow:var(--shadow)}.subject-icon{width:48px;height:48px;border-radius:14px;background:var(--sky);color:var(--blue);display:grid;place-items:center;font-size:1.35rem;margin-bottom:1.7rem}.subject-card strong{font:700 1.02rem/1.25 var(--serif)}.subject-card small{color:var(--muted);margin-top:.2rem}.subject-arrow{position:absolute;right:1.3rem;top:1.3rem;color:#9aacb6}.book-card{display:flex;flex-direction:column;border:1px solid var(--border);border-radius:var(--radius);background:#fff;overflow:hidden;transition:.25s}.book-card:hover{transform:translateY(-7px);box-shadow:var(--shadow);border-color:transparent}.book-cover{height:315px;background:linear-gradient(145deg,#edf3f5,#f9faf8);display:grid;place-items:center;position:relative;padding:2.1rem 1.5rem}.book-cover img{height:235px;width:auto;object-fit:contain;filter:drop-shadow(10px 15px 12px rgba(19,42,57,.22));transition:transform .3s}.book-card:hover .book-cover img{transform:scale(1.035) rotate(-1deg)}.book-badge{position:absolute;left:1rem;top:1rem;background:var(--navy);color:#fff;border-radius:20px;padding:.3rem .65rem;font-size:.67rem;font-weight:700;letter-spacing:.04em}.book-body{display:flex;flex:1;flex-direction:column;padding:1.25rem}.book-subject{text-transform:uppercase;letter-spacing:.1em;font-size:.67rem;color:var(--blue);font-weight:800;margin-bottom:.5rem}.book-title{font:700 1rem/1.4 var(--serif);min-height:2.8em;margin:0 0 .55rem}.book-title a:hover{color:var(--blue)}.book-author{font-size:.75rem;line-height:1.45;color:var(--muted);min-height:2.2em;margin-bottom:1.15rem}.book-price{display:block;font-weight:800;color:var(--navy);font-size:.95rem}.book-body del{color:#9ba6ac;font-size:.72rem}.add-to-cart{width:42px;height:42px;border-radius:50%;border:1px solid var(--border);background:#fff;color:var(--navy);transition:.2s}.add-to-cart:hover,.add-to-cart.is-added{background:var(--navy);border-color:var(--navy);color:#fff}
.heritage-section{background:var(--navy);color:#fff;overflow:hidden}.heritage-visual{position:relative}.heritage-visual img{width:100%;height:480px;object-fit:cover;border-radius:28px;box-shadow:0 25px 50px rgba(0,0,0,.25)}.year-card{position:absolute;bottom:-25px;right:-25px;width:180px;height:180px;background:var(--gold);color:var(--navy-2);border-radius:50%;display:flex;flex-direction:column;justify-content:center;text-align:center;padding:1rem;border:8px solid var(--navy)}.year-card strong{font:700 3rem/1 var(--serif)}.year-card span{font-size:.72rem;line-height:1.3;font-weight:700;margin-top:.4rem}.heritage-section h2{font:700 clamp(2.2rem,4vw,3.8rem)/1.12 var(--serif);letter-spacing:-.04em;margin:1rem 0 1.5rem}.heritage-section p{color:#c6d6df}.heritage-stats{display:flex;gap:2.2rem;border-top:1px solid rgba(255,255,255,.16);margin-top:2.25rem;padding-top:1.5rem}.heritage-stats strong,.heritage-stats span{display:block}.heritage-stats strong{font:700 1.2rem var(--serif);color:#fff}.heritage-stats span{font-size:.7rem;color:#9fb5c2}.feature-card{position:relative;display:block;min-height:370px;padding:2rem;border-radius:24px;overflow:hidden;color:#fff;transition:.25s}.feature-card:hover{transform:translateY(-5px);color:#fff;box-shadow:var(--shadow)}.feature-card:after{content:"";position:absolute;width:260px;height:260px;border-radius:50%;right:-100px;bottom:-110px;background:rgba(255,255,255,.07)}.feature-ebook{background:#1e6c89}.feature-library{background:#173f60}.feature-author{background:#8b5c30}.feature-number{position:absolute;right:1.5rem;top:1rem;font:700 4rem var(--serif);opacity:.12}.feature-card>i{font-size:2rem}.feature-card h3{font:700 1.55rem var(--serif);margin:5.5rem 0 .75rem}.feature-card p{color:rgba(255,255,255,.76);max-width:290px}.feature-card>span:last-child{display:inline-block;font-size:.83rem;font-weight:700;margin-top:1.25rem}.publisher-section p{color:var(--muted)}.publisher-board{background:#fff;border:1px solid var(--border);border-radius:24px;padding:1.5rem;box-shadow:var(--shadow)}.publisher-board img{width:100%;mix-blend-mode:multiply}.newsletter-section{padding:0 0 6.5rem;background:linear-gradient(#fff 50%,var(--navy-2) 50%)}.newsletter-card{background:var(--blue);color:#fff;padding:3.25rem;border-radius:28px;box-shadow:0 20px 55px rgba(20,71,108,.25)}.newsletter-card h2{font:700 clamp(2rem,3vw,3rem)/1.15 var(--serif);margin:.6rem 0}.newsletter-card p{margin:0;color:#d7e7f1}.newsletter-form{display:flex;background:#fff;border-radius:14px;padding:.4rem}.newsletter-form input{min-width:0;flex:1;border:0;outline:0;padding:.85rem;color:var(--ink)}.newsletter-card small{display:block;margin-top:.65rem;color:#d7e7f1}.site-footer{background:var(--navy-2);color:#adbfcb}.footer-main{padding:5rem 1rem 3.5rem}.footer-logo{display:block;background:#fff;border-radius:10px;padding:.65rem 1rem;width:max-content}.footer-logo img{width:245px}.site-footer h2{font:700 .8rem var(--sans);letter-spacing:.12em;text-transform:uppercase;color:#fff;margin-bottom:1.25rem}.site-footer ul{list-style:none;padding:0;margin:0}.site-footer li{margin:.55rem 0}.site-footer a:hover{color:#fff}.social-links{display:flex;gap:.5rem;margin-top:1.5rem}.social-links a{width:38px;height:38px;border:1px solid #345069;border-radius:50%;display:grid;place-items:center}.site-footer address{display:flex;gap:.75rem;font-style:normal}.site-footer address i,.footer-contact i{color:var(--gold)}.footer-contact a{display:flex;gap:.75rem;margin:.6rem 0}.footer-bottom{display:flex;justify-content:space-between;border-top:1px solid #284156;padding:1.4rem 1rem;font-size:.75rem}.footer-bottom div{display:flex;gap:1.5rem}
@media (max-width:1199.98px){.navbar-brand img{width:230px}.navbar .nav-link{padding:.6rem .55rem!important;font-size:.86rem}.book-cover{height:280px}.year-card{right:-10px}}
@media (max-width:991.98px){.min-vh-hero{min-height:520px}.hero-backdrop{background:linear-gradient(90deg,rgba(7,30,49,.97),rgba(7,30,49,.72)),url('../images/hero-library.jpg') 65% center/cover}.section-space{padding:4.5rem 0}.benefit:nth-child(2){border-right:0}.benefit:nth-child(-n+2){border-bottom:1px solid var(--border)}.heritage-visual img{height:390px}.newsletter-section{padding-bottom:4.5rem}.newsletter-card{padding:2.25rem}.footer-main{padding-top:4rem}}
@media (max-width:575.98px){.container{--bs-gutter-x:1.35rem}.navbar-brand img{width:190px}.nav-icon:first-child{display:none}.nav-icon{width:38px;height:38px}.min-vh-hero{min-height:540px}.hero-section h1{font-size:2.65rem}.hero-lead{font-size:1rem}.hero-search{padding:.35rem}.hero-search input{font-size:.82rem;padding:.75rem .45rem}.hero-search button{padding:.75rem .9rem}.popular-searches{display:none}.benefit{padding:1rem .5rem;gap:.55rem}.benefit>i{font-size:1.2rem}.benefit strong{font-size:.74rem}.benefit span{font-size:.62rem}.section-space{padding:3.75rem 0}.section-heading{margin-bottom:1.75rem}.subject-card{min-height:165px;padding:1rem}.subject-icon{margin-bottom:1.25rem}.subject-arrow{right:1rem;top:1rem}.book-cover{height:230px;padding:1.5rem .75rem}.book-cover img{height:175px}.book-body{padding:1rem}.book-title{font-size:.87rem;min-height:3.8em}.book-author{font-size:.68rem}.book-price{font-size:.83rem}.add-to-cart{width:36px;height:36px}.heritage-visual img{height:300px}.year-card{width:130px;height:130px;bottom:-15px}.year-card strong{font-size:2rem}.heritage-section h2{font-size:2.35rem}.heritage-stats{gap:1rem;justify-content:space-between}.feature-card{min-height:310px}.feature-card h3{margin-top:3.5rem}.publisher-board{padding:.6rem}.newsletter-card{padding:1.6rem;border-radius:20px}.newsletter-form{display:block;background:transparent;padding:0}.newsletter-form input{width:100%;border-radius:10px;margin-bottom:.6rem}.newsletter-form button{width:100%}.footer-bottom{flex-direction:column;gap:.8rem}}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important;animation:none!important}}
.bestseller-section{padding-top:0}.nav-shell.is-scrolled{position:fixed;left:0;right:0;top:0;box-shadow:0 8px 28px rgba(16,47,74,.12);animation:header-in .25s ease both}@keyframes header-in{from{transform:translateY(-100%)}to{transform:translateY(0)}}

/* Light footer theme */
.newsletter-section{background:#fff}
.site-footer{background:#fff;color:var(--muted);border-top:1px solid var(--border)}
.footer-logo{background:transparent;padding:0}
.site-footer h2{color:var(--navy)}
.site-footer a{color:#526775;transition:color .2s}
.site-footer a:hover{color:var(--blue)}
.social-links a{border-color:var(--border)}
.social-links a:hover{background:var(--navy);border-color:var(--navy);color:#fff}
.footer-bottom{border-top-color:var(--border);color:#788892}
.section-heading-wide{max-width:none;width:100%}.section-heading-wide>.text-link{margin-top:.15rem}

/* Premium four-slide hero */
.hero-section .carousel{background:var(--navy-2)}
.hero-slide{position:relative;isolation:isolate;background-position:center;background-size:cover;background-repeat:no-repeat}
.hero-slide::before{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(90deg,rgba(5,25,42,.97) 0%,rgba(7,31,51,.88) 42%,rgba(7,31,51,.28) 76%,rgba(7,31,51,.1) 100%)}
.hero-slide::after{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(180deg,rgba(0,0,0,.08),rgba(4,23,38,.28))}
.hero-wind{background-image:url('../images/hero-library.jpg')}
.hero-biodiversity{background-image:url('../images/hero-slide-2.jpg')}
.hero-agriculture{background-image:url('../images/hero-slide-3.jpg')}
.hero-physics{background-image:url('../images/hero-slide-4.jpg')}
.hero-biodiversity::before,.hero-physics::before{background:linear-gradient(270deg,rgba(5,22,38,.98) 0%,rgba(7,27,46,.9) 43%,rgba(7,27,46,.3) 74%,rgba(7,27,46,.12) 100%)}
.hero-copy-right{padding-left:3rem}
.hero-btn{display:inline-flex;align-items:center;gap:.75rem;background:var(--gold);color:var(--navy-2);font-weight:800;padding:.9rem 1.35rem;border-radius:12px;box-shadow:0 12px 30px rgba(0,0,0,.18);transition:transform .2s,background .2s}
.hero-btn:hover{color:var(--navy-2);background:#f2b952;transform:translateY(-2px)}
.hero-btn i{transition:transform .2s}.hero-btn:hover i{transform:translateX(4px)}
.hero-indicators{justify-content:flex-start;left:max(1rem,calc((100% - 1288px)/2));right:auto;bottom:1.4rem;margin:0;gap:.45rem}
.hero-indicators [data-bs-target]{width:34px;height:3px;margin:0;border:0;border-radius:5px;background:#fff;opacity:.4;transition:width .3s,opacity .3s}
.hero-indicators .active{width:64px;opacity:1;background:var(--gold)}
.hero-control{width:46px;height:46px;top:50%;bottom:auto;margin-top:-23px;border:1px solid rgba(255,255,255,.35);border-radius:50%;background:rgba(8,30,48,.5);opacity:0;transition:opacity .2s,background .2s}
.hero-control.carousel-control-prev{left:1.25rem}.hero-control.carousel-control-next{right:1.25rem}.hero-section:hover .hero-control,.hero-control:focus{opacity:1}.hero-control:hover{background:var(--gold);color:var(--navy)}
.hero-section .carousel-item.active .eyebrow,.hero-section .carousel-item.active h1,.hero-section .carousel-item.active .hero-lead,.hero-section .carousel-item.active .hero-search,.hero-section .carousel-item.active .hero-btn{animation:hero-content-in .7s ease both}
.hero-section .carousel-item.active h1{animation-delay:.08s}.hero-section .carousel-item.active .hero-lead{animation-delay:.15s}.hero-section .carousel-item.active .hero-search,.hero-section .carousel-item.active .hero-btn{animation-delay:.22s}
@keyframes hero-content-in{from{opacity:0;transform:translateY(18px)}to{opacity:1;transform:translateY(0)}}
@media (max-width:991.98px){.hero-slide::before,.hero-biodiversity::before,.hero-physics::before{background:linear-gradient(90deg,rgba(5,25,42,.95),rgba(5,25,42,.68))}.hero-copy-right{padding-left:0}.hero-indicators{left:1rem}.hero-control{display:none}}
@media (max-width:575.98px){.hero-slide{background-position:center}.hero-slide::before,.hero-biodiversity::before,.hero-physics::before{background:rgba(5,25,42,.79)}.hero-section .carousel-item h1{font-size:2.5rem}.hero-indicators{bottom:1rem}.hero-indicators [data-bs-target]{width:24px}.hero-indicators .active{width:42px}}