:root{font-family:Arial,'Segoe UI',sans-serif;color:#16324f;background:#eef7fa;--ink:#16324f;--accent:#087e8b;--background:#eef7fa;--karaoke:#cff3ec;--line:#087e8b55;--bar-height:76px}*{box-sizing:border-box}body{margin:0}button,input,select,textarea{font:inherit}button{cursor:pointer;border:0}button:disabled{opacity:.35;cursor:default}[hidden]{display:none!important}button:focus-visible,select:focus-visible,input:focus-visible,textarea:focus-visible{outline:3px solid var(--accent);outline-offset:3px}i[data-icon]{display:inline-flex;flex:none}i svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
#welcome{min-height:100dvh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:28px;gap:32px}#welcome h1{font-size:30px;letter-spacing:1.5px;margin:0;color:var(--ink)}#welcome h1 span{color:var(--accent)}.book-choices{display:flex;align-items:stretch;justify-content:center;gap:38px}.book-choice{display:flex;flex-direction:column;align-items:center;gap:18px;padding:14px 14px 20px;border-radius:12px;background:#fff;border:1px solid var(--line);box-shadow:0 8px 24px #16324f12;color:var(--ink)}.book-choice:hover{border-color:var(--accent);box-shadow:0 8px 30px #16324f25}.book-choice img{width:min(30vw,290px);height:auto;display:block}.book-choice strong{font-size:20px;font-weight:600}
#reader{height:100dvh;display:flex;flex-direction:column}.reader-heading{height:48px;flex:none;display:flex;align-items:center;gap:25px;padding:0 24px;background:var(--ink);color:white}.reader-heading strong{font-size:20px;letter-spacing:1px}.reader-heading strong span{color:#cff3ec}#bookLabel{font-size:12px}#pageBadge{margin-left:auto;font-size:12px;color:#cff3ec}#viewport{flex:1;min-height:0;overflow:auto;padding:18px;display:flex;justify-content:center;align-items:flex-start;margin-bottom:var(--bar-height)}#paper,#activityPaper{position:relative;flex:none;background:#fff;--paper-width:800px}#paper{box-shadow:0 5px 25px #16324f15}#pageImage,#activityImage{display:block;width:100%;height:auto;user-select:none}#pageCanvas,#activityCanvas{position:absolute;inset:0;width:100%;height:100%;z-index:4;pointer-events:none}.drawing canvas{pointer-events:auto!important;touch-action:none;cursor:crosshair}.hotspot{position:absolute;z-index:3;width:30px;height:30px;border-radius:7px;background:var(--accent);color:white;border:2px solid #fff;box-shadow:0 1px 6px #0003;padding:0;display:grid;place-items:center;font-size:12px;font-weight:700}.hotspot.media{background:var(--ink)}.hotspot svg{width:17px;height:17px}.hotspot:hover{filter:brightness(1.15)}
.bottom-bar{height:var(--bar-height);background:var(--ink);color:white;display:flex;align-items:center;gap:8px;padding:12px 18px;overflow-x:auto;overscroll-behavior:contain;box-shadow:0 -3px 15px #16324f25;z-index:20}.bottom-bar button,.bottom-bar select{background:var(--accent);border:1px solid #1896a2;color:#fff;min-height:44px;min-width:40px;border-radius:8px;padding:9px 12px;display:flex;align-items:center;justify-content:center;gap:7px;white-space:nowrap;flex:none;font-size:13px}.bottom-bar button:hover{background:#0b919e}.bottom-bar button[aria-pressed=true]{background:#cff3ec;border-color:#cff3ec;color:#16324f}.bottom-bar select{width:104px;display:block}.bottom-bar option{background:white;color:#16324f}.bottom-bar button:focus-visible,.bottom-bar select:focus-visible{outline-color:#cff3ec}.pagination{display:flex;gap:5px;margin:0 6px}#toolbar{position:fixed;bottom:0;left:0;right:0;justify-content:center}.bar-spacer{flex:1;min-width:0}
.tool-popover{position:fixed;right:18px;bottom:calc(var(--bar-height) + 12px);z-index:100;width:285px;padding:16px;background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:0 12px 60px #16324f40;color:var(--ink)}.tool-popover>strong{font-size:14px}.palette-row{display:flex;gap:8px;margin-top:14px;align-items:center}.palette-row button{display:grid;place-items:center;background:var(--background);color:var(--ink);border:1px solid var(--line);border-radius:7px;min-width:39px;height:39px;padding:5px}.palette-row button[aria-pressed=true]{outline:2px solid var(--accent);outline-offset:2px}.colors button{background:var(--swatch);width:28px;min-width:28px;height:28px;border:4px solid white;box-shadow:0 0 0 1px var(--line);border-radius:50%}.colors input{width:29px;height:29px;padding:0;border:0;background:none}.thickness{font-size:12px;display:flex;gap:10px;align-items:center;margin-top:18px}.thickness input{width:168px;accent-color:var(--accent)}
dialog{width:98vw;max-width:1800px;height:96dvh;max-height:96dvh;padding:0;border:1px solid var(--line);border-radius:10px;overflow:hidden;background:var(--background);color:var(--ink);box-shadow:0 20px 70px #10243b60}dialog::backdrop{background:#102a43ce}.dialog-heading{height:37px;padding:10px 18px;background:var(--ink);color:#cff3ec;font-size:12px}.dialog-heading span{display:block}#modalBody{height:calc(100% - 37px - var(--bar-height));overflow:auto;padding:16px;display:flex;align-items:flex-start;justify-content:center}#modalContent{position:relative;flex:none;min-width:0}#activityPaper{margin:0 auto;box-shadow:0 4px 25px #16324f14}#answerLayer{position:absolute;inset:0;z-index:2;pointer-events:none}.book-answer{position:absolute;color:#08666c;font-weight:700;line-height:1.08;padding:1px;display:flex;justify-content:center;align-items:center;text-align:center;white-space:pre-line;overflow:hidden;background:#ffffffd9;border-radius:2px;font-size:calc(var(--paper-width)*var(--font)/100)}.book-answer.mark{background:transparent;padding:0;font-family:Arial,sans-serif}.modal-controls{position:absolute;bottom:0;left:0;right:0;padding:10px 12px;gap:7px}.modal-controls button{font-size:13px;padding:9px 11px}#answerCount{font-size:12px;color:#cff3ec;white-space:nowrap}.modal-expanded{width:100vw!important;height:100dvh!important;max-width:none!important;max-height:none!important;top:0!important;left:0!important;margin:0!important;border:0!important;border-radius:0!important}.modal-expanded .dialog-heading{height:32px;padding:8px 18px}.modal-expanded #modalBody{height:calc(100% - 32px - var(--bar-height))}#contextActions{display:flex;align-items:center;gap:7px;flex:none}
.player-controls{display:flex;align-items:center;gap:8px;flex:none}.player-controls .player-play{min-width:70px}.media-seek{width:clamp(85px,12vw,180px);accent-color:var(--accent);cursor:pointer}.media-time{font-size:11px;color:#cff3ec;min-width:68px;white-space:nowrap}.speed-control select{width:64px;padding:9px 5px;font-size:12px}.media-shell{width:100%;height:100%;display:flex;align-items:center;justify-content:center}.media-shell video{display:block;max-height:100%;max-width:100%;width:auto;height:auto;background:#111;object-fit:contain}.media-shell audio{display:none}#modalContent.video-content{height:100%;width:100%}#karaokePanel{position:absolute;bottom:calc(var(--bar-height) + 12px);right:18px;width:min(700px,calc(100% - 36px));max-height:50%;overflow:auto;background:white;border:1px solid var(--accent);border-radius:10px;padding:9px;box-shadow:0 10px 40px #16324f40;z-index:10}.karaoke-line{display:block;width:100%;text-align:left;border:1px solid transparent;background:white;color:var(--ink);border-radius:6px;margin:3px 0;padding:12px 16px;font-size:inherit;line-height:1.5;cursor:pointer}.karaoke-line strong{color:var(--accent);font-size:.72em;display:block;margin-bottom:4px}.karaoke-line.karaoke-active{background:var(--karaoke);border-color:var(--accent)}.script-page{width:100%;height:auto;display:block;margin-bottom:15px}.media-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px;width:min(1000px,90vw);margin:auto}.media-grid button{padding:22px;border:1px solid var(--line);border-radius:9px;background:white;color:var(--ink);display:flex;align-items:center;gap:15px;font-size:20px}.teacher-pages{max-width:950px;margin:auto}.teacher-pages img{display:block;width:100%;height:auto;margin-bottom:24px}.note-area{width:min(800px,88vw);height:50vh;background:white;border:1px solid var(--line);padding:18px;border-radius:8px;color:var(--ink);font-size:22px;resize:vertical}.notice{margin:30px;max-width:750px;font-size:24px;line-height:1.5}#toast{position:fixed;bottom:calc(var(--bar-height) + 18px);left:50%;transform:translateX(-50%);background:var(--ink);color:white;padding:12px 20px;border-radius:8px;font-size:13px;z-index:150;max-width:90vw}
@media(max-width:1100px){#toolbar button span{display:none}#toolbar #pen span{display:inline}.modal-controls button span{font-size:11px}.modal-controls button{padding:8px;gap:4px}.modal-controls button svg{width:18px;height:18px}.media-seek{width:90px}.media-time{min-width:58px;font-size:10px}.player-controls{gap:6px}.bottom-bar{gap:6px;padding:10px}}
@media(max-width:700px){:root{--bar-height:70px}.reader-heading{padding:0 14px;gap:15px;height:42px}.reader-heading strong{font-size:17px}#bookLabel{font-size:10px}#viewport{padding:12px}.book-choices{gap:18px}.book-choice{padding:9px 9px 16px;gap:12px}.book-choice img{width:37vw}.book-choice strong{font-size:16px}dialog{width:100vw;max-width:100vw;height:98dvh;max-height:98dvh}.modal-controls button span{display:none}.modal-controls #showAnswer span,.modal-controls #hideAnswers span{display:block;font-size:11px}.modal-controls #showAnswer svg,.modal-controls #hideAnswers svg{display:none}.bottom-bar button{min-width:38px;min-height:42px;padding:8px}.bottom-bar select{width:86px;min-height:42px}.pagination{margin:0;gap:3px}#modalBody{padding:10px}#karaokeLines{font-size:23px}.media-seek{width:75px}.media-time{font-size:9px;min-width:55px}.player-controls .player-play{min-width:45px}.player-controls .player-play span{display:block}.tool-popover{right:10px;width:280px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}

audio{display:none}#karaokeLines{font-size:28px}.book-answer.beside{justify-content:flex-start;text-align:left;padding:6px 10px;line-height:1.16;border-left:3px solid var(--accent);background:#eefaf8}.book-answer.choice{background:#cff3ec60;border:2px solid #087e8b;border-radius:10px}.book-answer{overflow-wrap:anywhere}.modal-controls #modalClose,.modal-controls #modalFullscreen{position:sticky;right:0;z-index:3;box-shadow:0 0 0 5px var(--ink)}.modal-controls #modalFullscreen{right:82px}
.book-answer.beside{padding:.2em .45em} .book-answer.choice{box-shadow:inset 0 0 0 1px #ffffffaa}
@media(max-width:1200px){.modal-controls button span{display:none}.modal-controls #showAnswer span,.modal-controls #hideAnswers span{display:inline;font-size:11px}.modal-controls #showAnswer svg,.modal-controls #hideAnswers svg{display:none}.modal-controls button{min-width:36px;padding:8px}.modal-controls #modalFullscreen{right:48px}.player-controls .player-play{min-width:36px}.player-controls .player-play span{display:none}.media-seek{width:70px}.media-time{min-width:50px;font-size:10px}.speed-control select{width:52px}.modal-controls{gap:5px}.player-controls{gap:5px}#contextActions{gap:5px}}

.book-answer,.book-answer.beside,.book-answer.choice{background:transparent!important;box-shadow:none!important;border:0;border-radius:0}
.book-answer.beside{padding:.15em .3em}.book-answer.choice{border:2px solid #16824a;border-radius:10px}
.book-answer.correct{color:#16824a}.book-answer.incorrect{color:#cf303b}
.interaction-icon{animation:interaction-cue 2.8s ease-in-out infinite}.interaction-icon svg{width:20px;height:20px}
@keyframes interaction-cue{0%,65%,100%{transform:translateY(0) rotate(0)}75%{transform:translateY(-2px) rotate(-3deg)}85%{transform:translateY(0) rotate(2deg)}}
@media(prefers-reduced-motion:reduce){.interaction-icon{animation:none}}
#karaokePanel.reading-text{inset:48px 16px calc(var(--bar-height) + 12px);width:auto;max-height:none;padding:16px;background:#fff}
.reading-page{display:block;width:100%;height:auto;max-width:1450px;margin:0 auto}
#textToggle span,#karaokeToggle span{display:inline!important}
@media(max-width:1200px){.modal-controls button{min-width:32px;padding:6px}.modal-controls{gap:4px}#contextActions,.player-controls{gap:4px}.media-seek{width:50px}.media-time{min-width:44px}.speed-control select{width:44px}.modal-controls #nextActivity span{display:none}#textToggle span,#karaokeToggle span{font-size:11px}}

.book-answer.underline{background:#ffd84d66!important;border-bottom:3px solid #16824a!important;border-radius:0}
.book-answer.cw{font-weight:700}
.book-answer.choice.round{border-radius:50%}