:root{color-scheme:light;--ink:#103b66;--muted:#48677f;--line:#b4d7e6;--paper:#fffdf6;--mint:#daf4eb;--blue:#0077e7}
*{box-sizing:border-box}body{margin:0;color:var(--ink);font-family:"Yu Gothic","Hiragino Kaku Gothic ProN",Meiryo,sans-serif;background:radial-gradient(ellipse at 8% 5%,#dff7ff,transparent 40rem),linear-gradient(#f5fcff,#fffdf7);line-height:1.65}[hidden]{display:none!important}button,input,select{font:inherit}button,a,input,select,summary{-webkit-tap-highlight-color:transparent}button{cursor:pointer;border:1px solid var(--line);border-radius:22px;padding:10px 18px;min-height:48px;background:#fff;color:var(--ink);font-weight:700;touch-action:manipulation}button:hover:not(:disabled){background:#eefaff;border-color:#4d9ed7}button:disabled{cursor:default;opacity:.58}button.primary{background:var(--dm-action-fill,linear-gradient(#009eff,#0070e5));border-color:transparent;box-shadow:var(--dm-action-shadow,inset 0 2px 2px #9be5ff);color:#fff}button.primary:hover:not(:disabled){background:#0068d3}a{color:#005bad}a:hover{text-decoration-thickness:2px}:focus-visible{outline:3px solid #ad6700;outline-offset:4px}summary{cursor:pointer;min-height:44px;padding:8px;font-weight:700}ruby{ruby-align:center}rt{font-family:"Yu Gothic",sans-serif;font-size:.42em;font-weight:500;letter-spacing:.06em}h1,h2,h3,p,figure{margin-top:0}h2{line-height:1.5}main{max-width:1060px;margin:26px auto;padding:0 24px 20px}.subject{display:inline-block;border-radius:50px;background:#ffe7f1;color:#9c1b57;padding:3px 13px;font-size:.85rem;font-weight:700}.eyebrow{font-weight:700;letter-spacing:.07em;font-size:.9rem;margin-bottom:9px}.welcome{display:grid;grid-template-columns:1.2fr 1fr;align-items:center;gap:16px;padding:16px 28px 22px}.welcome h1{font-size:clamp(2rem,4.5vw,3.25rem);line-height:1.55;margin:12px 0;color:#104776}.welcome h1>span{color:#0085b5}.welcome p:last-child{margin:12px 0 0}.welcome-art{position:relative;aspect-ratio:1.25;border-radius:45% 55% 45% 55%;background:radial-gradient(circle at 75% 24%,#fff9 0 6px,transparent 7px),radial-gradient(circle at 24% 60%,#fff9 0 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#a2cddba8;border-radius:22px;background:#ffffff6b;position:relative;display:flex;flex-direction:column;align-items:center;min-width:0;overflow:hidden;padding:1px 12px 12px;min-height:158px;color:var(--ink);box-shadow:0 4px 0 #78b9c51c}.fish-choice:hover:not(:disabled){background:#fffc;border-color:#1685ad}.fish-choice:focus-visible{outline-offset:1px;outline-width:4px}.fish-choice svg{display:block;width:min(100%,210px);height:110px;flex-shrink:0;pointer-events:none}.fish-label{font-family:"Yu Mincho","Hiragino Mincho ProN",serif;font-weight:600;background:#fffef9;border:1px solid #a9c9d4;border-radius:12px;min-width:82%;min-height:48px;padding:3px 10px;font-size:clamp(1.45rem,3.5vw,2rem);line-height:1.5;box-shadow:0 3px #5b94a21a;white-space:nowrap;pointer-events:none}.answer-key{position:absolute;top:9px;left:12px;font-size:.75rem;border:1px solid #9bc7d6;border-radius:50%;width:23px;height:23px;line-height:21px;background:#fff9;font-family:system-ui}.fish-choice:disabled{opacity:1}.fish-choice.correct{border:3px solid #168269}.fish-choice.selected:not(.correct){border:3px dashed #b8691a}.selected-mark{font-size:.72rem;position:absolute;bottom:1px}.choice-hint{text-align:center;margin:12px 0 0}.swimmer{animation:bob 4.8s ease-in-out infinite;transform-origin:center}.fish-tail{animation:tail 1.4s ease-in-out infinite;transform-origin:60px 63px}.fish-fin{animation:tail 2s ease-in-out infinite;transform-origin:108px 64px}.fish-choice:nth-child(2n) .swimmer{animation-delay:-2s}.fish-choice:nth-child(3n) .swimmer{animation-delay:-3s}@keyframes bob{50%{transform:translate(3px,-3px)}}@keyframes tail{50%{transform:scaleX(.88) rotate(4deg)}}.feedback{border-radius:22px;background:#edf8f4;padding:24px;border-left:6px solid #278878}.feedback[data-correct="false"]{background:#fff5e7;border-left-color:#be7827}.feedback 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28px}.result-list,.fish-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}.sticker{border:1px solid #c0dce4;border-radius:22px;background:#f7fcff;padding:14px;overflow-wrap:anywhere}.sticker ruby{font-family:"Yu Mincho",serif;font-size:1.55rem;font-weight:600}.sticker .marks{display:flex;flex-wrap:wrap;gap:5px;margin:10px 0}.marks span{border-radius:20px;padding:2px 6px;background:#ebeff3;font-size:.72rem;color:#486479}.marks .done{background:#d9f2e7;color:#1f625a}.sticker>summary{padding:0;list-style:none}.sticker>summary::-webkit-details-marker{display:none}.sticker .fish-card-heading .fish-illustration{width:100%;height:116px}.sticker .fish-card-heading small{display:block;text-align:right;color:#286c9a}.sticker[open] summary small{display:none}.sticker[open]{grid-column:1/-1;display:block;background:#fffdf2}.sticker[open]>summary .fish-illustration{height:150px}.sticker .fish-detail{margin-top:12px}.fish-detail p{margin-bottom:8px}.fish-detail a{font-size:.8rem}.book-totals{display:flex;gap:14px;margin:14px 0}.book-totals span{background:#edf8fc;border-radius:18px;padding:10px 14px;flex:1;font-size:.82rem}.book-totals b{display:block;font-size:1.25rem}.book-controls{display:flex;gap:15px;flex-wrap:wrap}.book-controls label{font-size:.9rem}.book-controls input,.book-controls select{display:block;max-width:100%;padding:9px 12px;border:1px solid #94bfcf;background:white;border-radius:12px;min-height:46px}.pagination{display:flex;gap:18px;align-items:center;justify-content:center;margin-top:24px}.motion-setting{display:flex;gap:9px;align-items:center;font-size:.87rem;min-height:44px;margin:14px 0}.motion-setting input{width:21px;height:21px;accent-color:#007ed7}.motion-setting span{font-size:.76rem;color:var(--muted)}.save-area{font-size:.82rem;color:var(--muted);margin:16px 0}.save-area p{margin:4px 0}.notice{padding:16px;border-radius:15px;background:#fff3d6}footer{display:flex;gap:24px;flex-wrap:wrap;margin:25px 0 15px;font-size:.83rem}.celebrate{padding:12px;border-radius:18px;background:#fff0b5}@keyframes appear{from{transform:scale(.95)}to{transform:scale(1)}}
@media(min-width:850px){body[data-screen="play"] main{max-width:870px}.ocean{gap:16px}.fish-choice{min-height:172px}}
@media(max-width:600px){main{padding:0 12px 16px;margin-top:14px}.welcome{padding:9px 6px 19px;grid-template-columns:1fr .65fr;gap:5px}.welcome h1{font-size:1.85rem}.welcome .eyebrow{font-size:.75rem}.welcome p:last-child{font-size:.85rem}.welcome-art{aspect-ratio:.86}.welcome-art svg{width:110%}.welcome-art>span{font-size:1.3rem;bottom:17%;padding:0 12px}.start-panel,.panel{padding:18px 14px;border-radius:23px}.levels{gap:6px}.levels label>span{padding:8px 3px;font-size:.84rem;min-height:66px;display:flex;flex-direction:column;justify-content:center}.levels small{font-size:.66rem}.start-buttons{gap:9px;margin-top:16px}.start-buttons strong{font-size:.96rem}.home-links{gap:9px}.home-links button{padding:8px}.play-head{gap:8px}.play-head button{padding:8px 12px}.play-head>span{font-size:.76rem}.play-head strong{font-size:.88rem}.question-card{padding:13px 10px;border-radius:22px}.question-word{font-size:2.7rem;line-height:1.4;margin-bottom:10px}.ocean{gap:8px;padding:10px 8px 16px;border-radius:18px}.fish-choice{padding:3px 6px 10px;min-height:131px;border-radius:17px}.fish-choice svg{height:78px;width:139px;max-width:100%}.fish-label{min-width:90%;font-size:1.43rem;padding:3px 6px;min-height:41px}.answer-key{top:5px;left:6px;width:20px;height:20px;line-height:18px;font-size:.65rem}.feedback{padding:16px 12px}.feedback h2{font-size:1.65rem}.answer-layout{grid-template-columns:1fr;gap:4px}.answer-layout figure{display:flex;align-items:center}.answer-layout figure>div{width:62%}.answer-layout figcaption{width:38%;font-size:.73rem}.answer-word{font-size:2.4rem}.answer-layout p{margin-bottom:8px}.next-bar{position:fixed;left:0;right:0;bottom:0;margin:0;padding:10px 14px max(10px,env(safe-area-inset-bottom))}body[data-feedback="true"] main{padding-bottom:90px}.result-actions{gap:8px}.result-actions button{font-size:.9rem;padding:9px}.result-list,.fish-cards{grid-template-columns:1fr 1fr;gap:9px}.sticker{padding:12px 9px;border-radius:18px}.sticker ruby{font-size:1.35rem}.sticker .marks{gap:4px}.sticker .fish-card-heading .fish-illustration{height:90px}.book-totals{gap:6px}.book-totals span{padding:9px 7px;font-size:.74rem}.book-totals b{font-size:1.05rem}.book-controls{gap:10px}.book-controls input{width:155px}.motion-setting{flex-wrap:wrap}.muted{font-size:.77rem}.choice-hint{font-size:.76rem}}
@media(max-height:740px) and (max-width:600px){main{margin-top:8px}.play-head{margin-bottom:4px}progress{margin:8px 0 10px}.question-word{font-size:2.2rem;margin-bottom:6px}.fish-choice svg{height:63px}.fish-choice{min-height:116px}.question-card h2{font-size:1.06rem}.question-card .eyebrow{margin-bottom:1px}.choice-hint{margin-top:7px}}
body[data-reduce-motion="true"] *,body[data-screen]:not([data-screen="play"]):not([data-screen="home"]) *{animation:none!important}body[data-feedback="true"] .ocean *{animation:none!important}@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;scroll-behavior:auto!important;transition:none!important}}
@media(prefers-contrast:more){.fish-choice{border-color:#37687a}.fish-label{border-color:#244f66}.muted,figcaption{color:#244760}}

/* Supplied illustrations: preserve complete fins/tails and native left/right orientation. */
.fish-illustration{display:block;position:relative;width:100%;min-width:0;max-width:100%;aspect-ratio:800/500}
.fish-cards>.sticker,.fish-detail>*{min-width:0}
.fish-image{display:block;width:100%;height:100%;object-fit:contain;object-position:center;transform:none}
.fish-image.is-silhouette{filter:brightness(0);opacity:.16}
.fish-image-fallback{display:grid;place-items:center;min-height:90px;padding:10px;color:var(--muted);font-size:.8rem}