/* MonsterMoo family picture books — reader + shelf. Mobile first, no horizontal scrolling at any width. */
.bk-body{background:#fff8ec;color:#3a2450;min-height:100vh;margin:0}
.bk-main{max-width:1100px;margin:0 auto;padding:12px 14px 120px;box-sizing:border-box;overflow-x:hidden}
.bk-main *{box-sizing:border-box}
.bk-head{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.bk-head h1{margin:6px 0;font-size:1.5rem}
.bk-back{display:inline-flex;align-items:center;justify-content:center;min-height:48px;min-width:48px;padding:0 12px;border-radius:999px;border:2px solid #e4d6c0;background:#fff;color:#3a2450;text-decoration:none;font-weight:800;font-size:1.05rem}
.bk-msg{font-size:1.1rem;color:#6b5b7a}
.bk-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,300px),1fr));gap:16px;margin-top:10px}
.bk-card{background:#fff;border:3px solid #3a2450;border-radius:20px;overflow:hidden}
.bk-open{display:block;color:#3a2450;text-decoration:none;padding:0 0 12px}
.bk-open .bk-art{border:0;border-radius:0}
.bk-ctitle{display:block;font-size:1.2rem;padding:10px 14px 2px;line-height:1.3}.bk-meta{display:block;padding:0 14px;color:#8a5bb8}
.bk-assign{padding:10px 14px 14px;border-top:2px dashed #e4d6c0;display:flex;flex-direction:column;gap:6px}
.bk-assign select,.bk-assign input{min-height:48px;font-size:1rem;border-radius:12px;border:2px solid #d9cbe8;padding:0 10px;width:100%;max-width:100%;background:#fff}
.bk-save{min-height:48px;border-radius:999px;border:0;background:#6d4cf5;color:#fff;font-weight:800;font-size:1rem;cursor:pointer}
.bk-amsg{margin:0;min-height:1.2em;color:#6b5b7a}
.bk-bar{position:sticky;top:0;z-index:5;display:flex;align-items:center;gap:10px;background:#fff8ec;padding:6px 0;border-bottom:2px solid #f0e2cb}
.bk-btitle{flex:1;min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;font-size:1.05rem}
.bk-pnum{font-weight:800;color:#8a5bb8;white-space:nowrap}
.bk-stage{margin-top:12px;touch-action:pan-y}
.bk-page{display:grid;gap:14px;grid-template-columns:minmax(0,1fr)}
@media (min-width:900px){.bk-page.sq{grid-template-columns:minmax(0,1fr) minmax(0,1fr);align-items:start}.bk-page.L-chapter.k-puzzle{grid-template-columns:minmax(0,1fr)}}
.bk-art{width:100%;background:#f3e7d3;border:4px solid #3a2450;border-radius:18px;overflow:hidden;aspect-ratio:16/9}
.bk-art.sq{aspect-ratio:1/1}
.bk-art:not(.bk-ready):not(.bk-noimg){background:linear-gradient(100deg,#f3e7d3 30%,#fbf3e6 50%,#f3e7d3 70%);background-size:300% 100%;animation:bk-sh 1.4s linear infinite}@keyframes bk-sh{to{background-position:-150% 0}}@media (prefers-reduced-motion:reduce){.bk-art{animation:none!important}}
.bk-art img{display:block;width:100%;height:100%;object-fit:cover}
.bk-page.wide .bk-art{max-height:62vh}.bk-page.wide .bk-art img{object-fit:contain;background:#f3e7d3}
.bk-noimg::after{content:'🖼️';display:flex;align-items:center;justify-content:center;height:100%;font-size:3rem}
.bk-text{display:flex;flex-direction:column;gap:6px;min-width:0}
.bk-line{display:block;width:100%;text-align:left;background:transparent;border:0;border-radius:12px;padding:8px 10px;min-height:48px;font:inherit;color:inherit;font-size:1.15rem;line-height:1.55;cursor:pointer;overflow-wrap:anywhere}
@media (hover:hover){.bk-line:hover{background:rgba(138,91,184,.08)}}.bk-line:focus-visible{outline:3px solid #8a5bb8}
.bk-line.mm-reading{background:#fff3b0;box-shadow:inset 0 0 0 2px #ffc93c}
.L-picture .bk-line.lang-zh{font-size:1.7rem;font-weight:800;text-align:center;line-height:1.4}
.L-picture .bk-line.lang-en{font-size:1.25rem;font-weight:700;color:#8a5bb8;text-align:center}
.bk-para{text-align:left;font-size:1.3rem;font-weight:700;line-height:1.8;color:#5a3a8a;padding:2px 4px}
.L-picture .bk-para .bk-line.lang-en{display:inline;width:auto;min-height:0;padding:.22em .28em;font-size:inherit;line-height:inherit;color:inherit;text-align:left;-webkit-box-decoration-break:clone;box-decoration-break:clone}
.bk-line.small{font-size:1rem!important;text-align:left!important;font-weight:500!important}
.bk-say{align-self:flex-start;min-height:48px;padding:0 16px;border-radius:999px;border:2px solid #8a5bb8;background:#fff;color:#5a3a8a;font-weight:800;font-size:1rem;cursor:pointer}
.bk-say.small{font-size:.95rem;align-self:center;margin-top:4px}
.bk-say.mm-reading{background:#fff3b0}
.bk-cover-t{background:rgba(255,255,255,.9);border:4px solid #3a2450;border-radius:20px;padding:8px;text-align:center}
.bk-h1{font-size:1.9rem!important;font-weight:900;text-align:center!important;line-height:1.2!important}
.bk-h2{font-size:1.3rem!important;font-weight:800;color:#8a5bb8;text-align:center!important}
.bk-series{font-weight:800;letter-spacing:.12em;text-transform:uppercase;color:#ff6fa8;font-size:.9rem;padding-bottom:4px}
.bk-word{background:#fff;border:3px solid #3a2450;border-radius:16px;padding:8px;text-align:center;display:flex;flex-direction:column;align-items:stretch}
.bk-wlab{font-size:.78rem;font-weight:800;letter-spacing:.1em;text-transform:uppercase;color:#ff6fa8}
.bk-word .bk-line{text-align:center}
.bk-wzh{font-size:2.4rem!important;font-weight:800;line-height:1.2!important}
.bk-wpy{font-size:1.3rem!important;font-weight:700;color:#8a5bb8}
.bk-wgl{font-size:1.05rem!important;color:#6b5b7a}
.bk-inset{background:#fffaf0;border:3px solid #3a2450;border-radius:14px;padding:6px;max-width:460px;width:100%;align-self:center}
.bk-svg{display:block;width:100%;height:auto;max-height:46vh}
.bk-puz{background:#fff;border:4px dashed #8a5bb8;border-radius:20px;padding:12px;display:flex;flex-direction:column;gap:10px}
.bk-puz h3{margin:0;color:#8a5bb8;font-size:1.3rem}
.bk-pbody{font-size:1.1rem}
.bk-field{display:flex;flex-wrap:wrap;align-items:center;gap:8px;padding:6px;border-radius:12px;border:2px solid transparent}
.bk-field label{flex:1 1 220px;font-weight:700}
.bk-field input{width:7.5em;max-width:100%;min-height:52px;font-size:1.4rem;text-align:center;border-radius:12px;border:3px solid #d9cbe8;font-weight:800}
.bk-field.bad{border-color:#f0a35e;background:#fff6e8}.bk-field.good input{border-color:#16a34a;background:#ecfdf3}
.bk-pick{display:flex;flex-wrap:wrap;gap:6px;flex:1 1 220px}
.bk-opt{min-height:48px;min-width:56px;padding:0 14px;border-radius:12px;border:3px solid #d9cbe8;background:#fff;font-size:1.05rem;font-weight:800;color:#3a2450;cursor:pointer}
.bk-opt[aria-pressed=true]{border-color:#6d4cf5;background:#ece7fe}
.bk-check{align-self:flex-start;min-height:52px;padding:0 22px;border-radius:999px;border:0;background:#6d4cf5;color:#fff;font-weight:800;font-size:1.1rem;cursor:pointer}
.bk-fb{margin:0;font-weight:800;font-size:1.1rem;padding:8px 10px;border-radius:12px}
.bk-fb.ok{background:#dcfce7;color:#166534}.bk-fb.try{background:#fef3c7;color:#92400e}.bk-fb.kind{background:#fdf2ff;color:#7a2a8a}
.bk-hint,.bk-worked{background:#f3ecff;border:2px solid #8a5bb8;border-radius:14px;padding:8px}
.bk-worked .bk-line,.bk-hint .bk-line{font-size:1.05rem}
.bk-out details{background:#f3ecff;border-radius:14px;padding:6px 10px}.bk-out summary{min-height:44px;display:flex;align-items:center;font-weight:800;cursor:pointer}
.bk-panel{background:#fffaf0;border-radius:14px;padding:6px}
.bk-choices{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,84px),1fr));gap:10px}
.bk-choice{min-height:84px;border-radius:18px;border:4px solid #d9cbe8;background:#fff;font-size:1.5rem;font-weight:900;color:#3a2450;cursor:pointer;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;padding:6px}
.bk-choice .bk-svg{width:56px;height:56px}
.bk-choice span{font-size:1.15rem}
.bk-choice.wrong{opacity:.45;border-style:dashed}.bk-choice.right{border-color:#16a34a;background:#ecfdf3;box-shadow:0 0 0 4px rgba(22,163,74,.2)}
.bk-ans{font-size:1.4rem!important;font-weight:900;text-align:center!important}
.bk-grown{background:#f3ecff;border:2px solid #8a5bb8;border-radius:12px;padding:8px}.bk-grown b{color:#8a5bb8}
.bk-answers h2{margin:4px 0;color:#8a5bb8}
.bk-adet{background:#fff;border:2px solid #e4d6c0;border-radius:14px;padding:4px 10px;margin:8px 0}
.bk-adet summary{min-height:48px;display:flex;align-items:center;font-weight:800;color:#ff4f93;cursor:pointer}
.bk-ded{font-style:italic;color:#8a5bb8;text-align:center!important}
.bk-nav{position:fixed;left:0;right:0;bottom:0;display:flex;justify-content:space-between;gap:12px;padding:10px max(14px,env(safe-area-inset-right)) calc(10px + env(safe-area-inset-bottom)) max(14px,env(safe-area-inset-left));background:linear-gradient(rgba(255,248,236,0),#fff8ec 35%);pointer-events:none}
.bk-turn{pointer-events:auto;width:72px;height:72px;border-radius:50%;border:4px solid #3a2450;background:#ffc93c;color:#3a2450;font-size:2.6rem;font-weight:900;line-height:1;cursor:pointer;box-shadow:0 4px 0 #3a2450}
.bk-main .bk-turn{width:72px;height:72px}@media (max-width:480px){.bk-main .bk-turn{width:60px;height:60px;font-size:2.2rem}}
.bk-turn:disabled{opacity:.3;cursor:default}