/* Book pages (v146): one page per workbook. Same look as Every Learner and Earth & Space. */
.bk{max-width:1080px;margin:0 auto;padding:16px 0 72px}
@media(max-width:1112px){.bk{padding-inline:16px}}
.bk section{padding-block:0}
.bk-crumbs{display:flex;flex-wrap:wrap;gap:8px;font:600 13px/1.4 var(--body,inherit);color:#3b4a63;margin:0 0 14px}
.bk-crumbs a{color:#3b4a63}
.bk-hero{display:grid;grid-template-columns:minmax(0,340px) minmax(0,1fr);gap:clamp(20px,4vw,44px);align-items:center;background:#15233c;color:#fff;border:2px solid #15233c;border-radius:20px;box-shadow:0 6px 0 #0b1426;padding:clamp(20px,4vw,40px)}
.bk-cov img{display:block;width:100%;height:auto;border-radius:10px;border:3px solid #fff;box-shadow:0 10px 30px rgba(0,0,0,.35);background:#fff}
.bk-eyebrow{margin:0 0 8px;font:800 13px/1.2 var(--body,inherit);letter-spacing:.1em;text-transform:uppercase;color:#ffd23f}
.bk-top h1{font-family:var(--display);font-size:clamp(34px,5vw,56px);line-height:1.03;margin:0;color:#fff}
.bk-sub{margin:8px 0 0;font-size:clamp(18px,2.2vw,22px);font-weight:700;color:#fff}
.bk-lede{margin:14px 0 0;font-size:18px;line-height:1.6;color:#e6edf9;max-width:60ch}
.bk-facts{list-style:none;padding:0;margin:18px 0 0;display:flex;flex-wrap:wrap;gap:10px}
.bk-facts li{background:rgba(255,255,255,.08);border:1.5px solid rgba(255,255,255,.35);border-radius:999px;padding:7px 14px;font-weight:700;font-size:15px;color:#fff}
.bk-facts b{color:#ffd23f;font-family:var(--display);font-size:20px;margin-right:6px}
.bk-buy{display:flex;flex-wrap:wrap;align-items:center;gap:12px;margin:22px 0 0}
.bk-price{font-family:var(--display);font-size:32px;color:#fff;margin-right:6px}
.bk-btn{display:inline-flex;align-items:center;gap:8px;min-height:48px;padding:11px 20px;border-radius:12px;border:2px solid #15233c;background:#fff;color:#15233c;font-weight:800;font-size:16px;text-decoration:none;box-shadow:0 3px 0 #15233c}
.bk-btn:hover{background:#fff8d6}
.bk-hero .bk-btn{border-color:#fff;box-shadow:none}
.bk-btn.bk-primary{background:#ffd23f;border-color:#ffd23f;color:#15233c}
.bk-btn.bk-primary:hover{background:#ffe27a}
.bk-fine{margin:12px 0 0;font-size:14.5px;line-height:1.5;color:#c9d4e6}
.bk-sec{margin-top:56px}
.bk-sec h2{font-family:var(--display);font-size:clamp(26px,3.2vw,34px);margin:0 0 12px;text-wrap:balance}
.bk-sec>p{font-size:17px;line-height:1.6;margin:0 0 16px;max-width:70ch}
.bk-topics{list-style:none;counter-reset:t;padding:0;margin:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,300px),1fr));gap:12px}
.bk-topics li{counter-increment:t;position:relative;background:#fff;border:2px solid #15233c;border-radius:14px;box-shadow:0 3px 0 #15233c;padding:14px 16px 14px 58px;display:grid;gap:4px;align-content:start}
.bk-topics li::before{content:counter(t);position:absolute;left:14px;top:14px;width:30px;height:30px;border-radius:50%;background:#ffd23f;border:2px solid #15233c;font:800 14px/26px var(--body,inherit);text-align:center;color:#15233c}
.bk-topics b{font-size:17px;color:#15233c;line-height:1.3}
.bk-topics span{font-size:15.5px;line-height:1.45;color:#3b4a63}
.bk-two{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}
@media(max-width:760px){.bk-two{grid-template-columns:minmax(0,1fr)}}
.bk-card{border:2px solid #15233c;border-radius:16px;box-shadow:0 4px 0 #15233c;padding:20px 22px}
.bk-two .bk-card:nth-child(1){background:#dcecfa}.bk-two .bk-card:nth-child(2){background:#fdebd6}
.bk-card h2{font-size:clamp(22px,2.6vw,27px)}
.bk-card p{margin:14px 0 0}
.bk-ticks{list-style:none;padding:0;margin:0;display:grid;gap:9px}
.bk-ticks li{position:relative;padding-left:30px;font-size:17px;line-height:1.5}
.bk-ticks li::before{content:"";position:absolute;left:0;top:4px;width:18px;height:18px;border-radius:5px;background:#ffd23f;border:2px solid #15233c}
.bk-faq{display:grid;gap:10px}
.bk-q{background:#fff;border:2px solid #15233c;border-radius:14px;box-shadow:0 3px 0 #15233c;padding:14px 18px}
.bk-q summary{font-weight:800;font-size:17px;cursor:pointer;color:#15233c}
.bk-q p{margin:10px 0 0;font-size:16.5px;line-height:1.6;color:#2a3852}
.bk-links{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,230px),1fr));gap:12px}
.bk-links a{display:block;height:100%;box-sizing:border-box;background:#fff;border:2px solid #15233c;border-radius:14px;box-shadow:0 3px 0 #15233c;padding:14px 16px;font-weight:800;color:#15233c;text-decoration:none}
.bk-links a:hover{background:#fff8d6}
@media(max-width:760px){.bk-hero{grid-template-columns:minmax(0,1fr)}.bk-cov{max-width:240px;margin:0 auto}.bk-price{font-size:28px}.bk-buy .bk-btn{flex:1 1 100%;justify-content:center}}
.bk-look{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}
@media(max-width:900px){.bk-look{grid-template-columns:repeat(2,minmax(0,1fr))}}
.bk-look figure{margin:0;display:grid;gap:8px}
.bk-look img{display:block;width:100%;height:auto;border:2px solid #15233c;border-radius:10px;box-shadow:0 4px 0 #15233c;background:#fff}
.bk-look a:hover img{transform:translateY(-2px)}
.bk-look figcaption{font-weight:800;color:#15233c;text-align:center}
.bk .bk-hero{padding:clamp(24px,4vw,44px)}
.bk-card .bk-fine{color:#3b4a63}