/* A single viewport-sized manga slate. Text stays readable; content changes, not the page. */
body.slate-page{background:#dededb;background-image:radial-gradient(#7776 .7px,transparent .7px);background-size:7px 7px;color:#161616;overflow:hidden;margin:0;height:100dvh;color-scheme:light}.slate-layout{height:100dvh;max-width:1220px;margin:auto;display:grid;grid-template-rows:70px minmax(0,1fr) 26px;gap:10px;padding:0 24px 8px}.slate-sitebar{display:flex;justify-content:space-between;align-items:center;padding:0 5px}.slate-brand{display:flex;align-items:center;gap:9px;color:#101010}.slate-brand>span{font:40px 'Bebas Neue',Impact,sans-serif;border:3px solid #111;line-height:1;padding:3px 7px;transform:rotate(-4deg)}.slate-brand>b{font:28px 'Bebas Neue',Impact,sans-serif;line-height:.85}.slate-brand small{display:block;font:10px monospace;letter-spacing:2px;margin-top:7px}.slate-account{display:flex;gap:12px}.slate-page button,.slate-page .ink-button{background:#fafaf7;color:#141414;border:2px solid #202020;border-radius:3px;font:600 15px 'DM Sans',Arial,sans-serif;min-height:42px;padding:9px 15px;box-shadow:2px 2px 0 #181818;transition:transform .1s,background .1s}.slate-page button:hover{background:#e6e6df;border-color:#111;transform:translate(-1px,-1px)}.slate-page button:active{transform:translate(2px,2px);box-shadow:none}.slate-page button:disabled{opacity:.4;box-shadow:none;transform:none}.slate-page .ink-button{background:#171717;color:#fff;display:inline-flex;align-items:center;justify-content:center;text-decoration:none}.manga-slate{min-height:0;position:relative;display:grid;grid-template-rows:20px 62px 4px minmax(0,1fr) 66px;background:#f8f8f2;border:4px solid #181818;border-radius:13px 8px 15px 6px;box-shadow:7px 7px 0 #171717,inset 0 0 0 4px #f8f8f2,inset 0 0 0 5px #999;overflow:hidden;isolation:isolate}.manga-slate:before{content:'';position:absolute;inset:7px;border:1px solid #aaa;border-radius:8px;pointer-events:none;z-index:-1}.slate-edge{display:flex;justify-content:space-between;padding:3px 15px;font:9px monospace;letter-spacing:1.6px;background:#171717;color:#eee}.slate-hud{display:flex;align-items:center;gap:15px;padding:8px 23px;border-bottom:2px solid #191919}.slate-hud>div{flex:1;min-width:0}.slate-hud small{display:block;font:11px monospace;text-transform:uppercase;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;margin-bottom:4px}.slate-hud strong{font-size:15px;display:block;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.slate-hud>span{font:12px monospace;white-space:nowrap}.slate-hud>button{min-width:40px;padding:5px;font-size:21px;box-shadow:none}.slate-meter{background:#d1d1ca}.slate-meter i{display:block;height:100%;background:#171717;transition:width .25s}.slate-stage{position:relative;min-height:0;overflow:hidden;padding:clamp(14px,2.5vh,28px) clamp(18px,4vw,55px);display:flex;align-items:stretch}.slate-lesson{width:100%;max-width:840px;margin:auto;max-height:100%;display:flex;flex-direction:column;gap:18px}.comic-kicker{font:12px monospace;letter-spacing:2px;display:flex;justify-content:space-between;align-items:center}.comic-kicker span{font:30px 'Bebas Neue',Impact,sans-serif;background:#111;color:#fff;transform:rotate(3deg);padding:0 8px}.slate-lesson h1{font:clamp(26px,3.6vw,46px)/1.08 'Bebas Neue',Impact,sans-serif;letter-spacing:.015em;max-width:none;margin:0;color:#171717;text-transform:uppercase}.comic-rule{height:10px;background:repeating-linear-gradient(135deg,#161616 0px,#161616 1px,transparent 1px,transparent 5px);width:80px}.comic-bubble{background:#fff;border:2px solid #171717;padding:clamp(16px,3vh,30px);box-shadow:4px 4px 0 #bbb;position:relative;border-radius:3px 15px 3px 15px}.comic-bubble:before{content:'';position:absolute;top:-12px;left:28px;width:20px;height:20px;background:#fff;border-top:2px solid #171717;border-left:2px solid #171717;transform:skew(-25deg) rotate(45deg)}.comic-bubble p{font-size:clamp(17px,1.65vw,23px);line-height:1.55;margin:0;max-width:65ch;color:#171717}.formula-bubble{border-width:3px;background:#f1f1ed}.formula-bubble:before{background:#f1f1ed}.beat-dots{display:flex;gap:8px;justify-content:center}.beat-dots i{width:7px;height:7px;border:1px solid #111;border-radius:50%}.beat-dots .on{background:#111;transform:scale(1.3)}.slate-controls{border-top:2px solid #111;display:flex;align-items:center;gap:12px;padding:10px 23px;background:repeating-linear-gradient(135deg,#fff,#fff 5px,#f2f2eb 5px,#f2f2eb 6px)}.slate-controls [data-phase]{font:11px monospace;letter-spacing:1px;margin-right:auto}.slate-controls [data-actions]{display:flex;gap:8px}.slate-controls [data-back]{width:43px}.slate-caption{display:flex;justify-content:space-between;gap:12px;font:10px monospace;letter-spacing:.6px;align-items:center}.slate-caption [data-source]{text-align:right;max-width:65%;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.slate-illustration{min-height:0;display:flex;justify-content:center;align-items:center;flex:1;max-height:210px;background:#151515;border:2px solid #151515;padding:10px;filter:grayscale(1)}.slate-illustration svg{width:100%;height:100%;max-height:190px;min-height:100px}.slate-player{width:100%;height:100%;min-height:0;display:flex;flex-direction:column;gap:12px}.slate-player .activity-intro{padding:0!important;border:0!important;margin:0}.slate-player .activity-intro .eyebrow{display:none}.slate-player .activity-intro h2{font:600 clamp(18px,2vw,25px)/1.3 'DM Sans',Arial,sans-serif;color:#111;margin:0;letter-spacing:-.02em}.slate-player [data-work]{padding:0!important;flex:1;min-height:0;display:flex;flex-direction:column;gap:10px}.slate-player [data-work]>.quiet{font-size:12px;line-height:1.3;margin:0;color:#444}.slate-player .activity-svg{flex:1;min-height:60px;max-height:250px;width:100%;height:100%;background:#151515;filter:grayscale(1)}.slate-player [data-response],.slate-player [data-help],.slate-player [data-pair-feedback],.slate-player [data-prediction-feedback],.slate-player [data-follow-feedback],.slate-player [data-solution]{display:none!important}.slate-player .prediction-card,.slate-player .followup-card{background:transparent;border:0;padding:0;display:flex;flex-direction:column;justify-content:center;flex:1;gap:12px}.slate-player .prediction-card h3,.slate-player .followup-card h3{font-size:24px;line-height:1.3;margin:0;color:#111}.slate-player .followup-card>p{font-size:16px;line-height:1.45;margin:0}.slate-player .teaching-label{color:#333;margin:0}.slate-player .tap-choices{gap:12px;margin:0;display:grid;grid-template-columns:1fr 1fr}.slate-player .tap-choices button{font-size:17px;line-height:1.4;min-height:60px;text-align:left;padding:15px}.slate-player button.chosen,.slate-player .matched{background:#171717;color:#fff;border-color:#171717}.slate-player .tap-match{margin:0;gap:20px;display:grid;grid-template-columns:minmax(120px,.8fr) minmax(200px,1.4fr);min-height:0;flex:1;align-items:center}.slate-player .tap-match>div{gap:10px}.slate-player .tap-match button{font-size:16px;line-height:1.4;min-height:55px;padding:13px}.slate-player .tap-match button small{color:inherit;font-size:12px}.slate-player .tap-match [aria-pressed=true]{background:#171717;border-color:#171717;color:#fff;box-shadow:4px 4px 0 #aaa}.slate-mini-nav{display:flex;justify-content:center;gap:16px;align-items:center;font:12px monospace;flex:none}.slate-mini-nav button{min-height:32px;padding:3px 12px;box-shadow:none}.slate-player .sequence-slots{font-size:14px;min-height:35px;margin:0;border:1px dashed #555;padding:8px;background:#fff;display:block;line-height:1.4}.slate-player .sequence-slots span{display:none}.slate-player .sequence-slots span:last-child{display:flex}.slate-player .sequence-slots b{background:#111;color:#fff;padding:3px 7px}.slate-player .space-picks{margin:0;gap:10px;display:grid;grid-template-columns:1fr 1fr}.slate-player .space-picks button{font-size:16px;min-height:52px;line-height:1.35;padding:10px}.slate-player .direction-buttons{display:grid;grid-template-columns:repeat(3,1fr);gap:8px}.slate-player .direction-buttons button{min-height:42px;padding:6px;font-size:14px}.slate-player .field-label{color:#222;font-size:14px;margin:0}.slate-player input{color:#111;background:#fff;border:2px solid #555;border-radius:2px;min-height:43px;font-size:17px;padding:8px}.slate-player input[type=range]{height:26px;min-height:26px;accent-color:#111;padding:0}.slate-player label:has([data-vector-angle]){display:none}.slate-player .tune-controls{display:flex;gap:18px;margin:0}.slate-player .tune-controls label{flex:1;min-width:0;font-size:14px}.slate-player .activity-readout{font:15px monospace;color:#111;margin:0;padding:8px;background:#eee;border:1px solid #222}.slate-player [data-model],.slate-player [data-experiment-view]{flex:1;min-height:60px;display:flex;max-height:220px}.slate-player .experiment-stages{display:flex;gap:8px;flex:none}.slate-player .experiment-stages button{flex:1;font-size:13px;min-height:42px;padding:7px}.slate-player .observation-note{background:#eee;color:#111;border-left:3px solid #111;padding:10px;margin:0}.slate-player .observation-note b{color:#111;font-size:12px}.slate-player .observation-note p{font-size:15px;line-height:1.35;margin:4px 0 0}.slate-player .katex-display{margin:10px 0;color:#111}.slate-player[data-type=numeric] [data-work]{justify-content:center;max-width:650px;width:100%;margin:auto}.slate-view-tabs{display:flex;gap:8px}.slate-view-tabs button{min-height:34px;padding:5px 12px;font-size:13px;box-shadow:none}.slate-player [data-solid]{flex:1;min-height:0;display:flex;flex-direction:column}.slate-player [data-solid]>*{display:none!important}.slate-player[data-view=model] .solid-canvas{display:block!important;flex:1;height:100%!important;min-height:80px;background:#151515;filter:grayscale(1)}.slate-player[data-view=projection] .projection-buttons{display:flex!important;gap:6px;padding:0;margin:0}.slate-player .projection-buttons b{display:none}.slate-player .projection-buttons button{font-size:12px;min-height:38px;padding:4px 8px}.slate-player[data-view=projection] [data-shadow]{display:flex!important;flex:1;min-height:0;padding:0;filter:grayscale(1);background:#151515}.slate-player [data-shadow] .projection-shadow-title,.slate-player [data-shadow] p{display:none}.slate-player [data-shadow] svg{height:100%;width:100%;min-height:0}.slate-player:not([data-view=bounds]) .projection-task,.slate-player:not([data-view=bounds]) .bound-inputs{display:none}.slate-player[data-view=bounds] [data-solid],.slate-player[data-view=bounds] [data-graph]{display:none}.slate-player[data-view=bounds] [data-work]{justify-content:center}.slate-player .projection-task,.slate-player .bound-inputs{padding:0;display:grid;gap:16px}.slate-player .projection-task>p{display:none}.slate-player [data-graph]{flex:1;min-height:0;display:flex;flex-direction:column}.slate-player [data-graph] .diagram-toolbar,.slate-player [data-graph] .legend,.slate-player [data-graph] .slider-row,.slate-player [data-graph] .region-caption{display:none!important}.slate-player [data-graph] svg{height:100%;max-height:100%;background:#151515;filter:grayscale(1)}.slate-off{display:none!important}.slate-sheet{position:absolute;inset:20px 0 0;z-index:20;background:#141414a8;display:flex;align-items:center;justify-content:center;padding:20px;backdrop-filter:blur(3px)}.speech-sheet{width:min(660px,100%);max-height:100%;background:#fff;color:#111;border:3px solid #111;box-shadow:7px 7px 0 #111;position:relative;padding:26px;display:flex;flex-direction:column;gap:18px;border-radius:14px 4px 14px 4px}.speech-sheet:before{content:'';position:absolute;inset:7px;border:1px solid #bbb;pointer-events:none}.speech-sheet>small{font:11px monospace;letter-spacing:1.7px}.speech-sheet h2{font:36px/1.05 'Bebas Neue',Impact,sans-serif;margin:0;padding-right:25px;color:#111}.speech-sheet p{font-size:18px;line-height:1.55;margin:0}.speech-sheet [data-sheet-x]{position:absolute;top:10px;right:10px;box-shadow:none;min-height:32px;padding:2px 9px;z-index:1}.speech-sheet [data-sheet-action]{align-self:flex-end}.speech-sheet nav{display:flex;align-items:center;justify-content:space-between}.slate-library-link{color:#111;text-decoration:underline;font-size:14px;display:inline-block;margin-top:15px}.chapter-picks{display:grid;gap:10px}.chapter-picks button{display:flex;gap:15px;align-items:center;text-align:left;font-size:15px}.chapter-picks b{font:25px 'Bebas Neue',Impact,sans-serif}.account-link{margin-top:20px}.manga-slate:fullscreen{height:100dvh;width:100vw;border-radius:0}.panel-enter{animation:slate-in .18s ease-out}@keyframes slate-in{from{opacity:0;transform:translateX(12px)}to{opacity:1;transform:translateX(0)}}
@media(max-width:650px){.slate-layout{padding:0 9px 5px;grid-template-rows:53px minmax(0,1fr) 19px;gap:7px}.slate-sitebar{padding:0 3px}.slate-brand>span{font-size:28px;padding:2px 5px}.slate-brand>b{font-size:22px}.slate-brand small{font-size:8px;letter-spacing:1px}.slate-account{gap:9px}.slate-account button{min-height:34px;padding:5px 10px;font-size:13px}.manga-slate{border-width:3px;box-shadow:4px 4px 0 #111;grid-template-rows:16px 50px 3px minmax(0,1fr) 62px}.slate-edge{font-size:7px;padding:3px 10px;letter-spacing:.5px}.slate-hud{padding:5px 10px;gap:8px}.slate-hud strong{font-size:12px}.slate-hud small{font-size:9px}.slate-hud>span{font-size:10px}.slate-hud>button{min-width:30px;min-height:31px;font-size:19px}.slate-stage{padding:14px 14px}.slate-lesson{gap:13px}.slate-lesson h1{font-size:29px}.comic-kicker{font-size:10px;letter-spacing:1px}.comic-kicker span{font-size:23px}.comic-bubble{padding:18px}.comic-bubble p{font-size:17px;line-height:1.5}.slate-illustration{max-height:160px}.slate-controls{gap:7px;padding:8px 9px}.slate-controls [data-phase]{display:none}.slate-controls [data-actions]{margin-left:auto;gap:5px}.slate-controls button{font-size:12px;min-height:39px;padding:6px 9px}.slate-controls [data-back]{width:31px;padding:4px}.slate-controls>[data-next]{margin-left:auto}.slate-controls [data-check]{max-width:67px;line-height:1.1}.slate-caption{font-size:8px;letter-spacing:0}.slate-caption>span:first-child{font-size:7px}.slate-player{gap:10px}.slate-player .activity-intro h2{font-size:18px;line-height:1.3}.slate-player .tap-choices{grid-template-columns:1fr;gap:12px}.slate-player .tap-choices button{font-size:16px;padding:13px;min-height:56px}.slate-player .prediction-card h3,.slate-player .followup-card h3{font-size:20px}.slate-player .tap-match{grid-template-columns:1fr;gap:14px;align-content:center}.slate-player .tap-match button{font-size:16px}.slate-player .tap-match button small{display:none}.slate-player .space-picks{grid-template-columns:1fr}.slate-player .direction-buttons{gap:6px}.slate-player .direction-buttons button{font-size:12px;min-height:39px;padding:6px 2px}.slate-player [data-work]>.quiet{font-size:11px;line-height:1.25}.slate-player .tune-controls{flex-direction:column;gap:5px}.slate-player .tune-controls label{font-size:12px}.slate-player input[type=range]{min-height:23px;height:23px}.slate-player .activity-readout{font-size:12px;padding:6px}.slate-player .activity-svg{max-height:190px}.slate-player [data-model],.slate-player [data-experiment-view]{max-height:170px}.slate-player .experiment-stages{gap:5px}.slate-player .experiment-stages button{font-size:11px;padding:5px;min-height:40px}.slate-player .observation-note{padding:8px}.slate-player .observation-note p{font-size:13px;line-height:1.35}.slate-player .field-label{font-size:13px}.slate-player .projection-buttons button{font-size:10px}.slate-sheet{padding:12px}.speech-sheet{padding:22px;gap:15px}.speech-sheet h2{font-size:30px}.speech-sheet p{font-size:16px;line-height:1.5}.speech-sheet [data-sheet-action]{min-height:42px}.chapter-picks{gap:9px}.chapter-picks button{font-size:14px;padding:10px;min-height:47px}}
@media(max-height:650px){.slate-layout{grid-template-rows:45px minmax(0,1fr) 16px;gap:5px}.manga-slate{grid-template-rows:14px 43px 3px minmax(0,1fr) 53px}.slate-stage{padding:10px 14px}.slate-lesson{gap:10px}.slate-lesson h1{font-size:25px}.comic-bubble{padding:12px}.comic-bubble p{font-size:16px;line-height:1.4}.comic-kicker span{font-size:19px}.slate-illustration{max-height:100px}.slate-player .activity-svg,.slate-player [data-model],.slate-player [data-experiment-view]{max-height:110px}.slate-player .activity-intro h2{font-size:16px}.slate-player .tap-choices button,.slate-player .tap-match button{min-height:44px;font-size:15px;padding:9px}.slate-player{gap:7px}.slate-player .direction-buttons button{min-height:33px}.slate-controls{padding:5px 9px}.speech-sheet{padding:18px;gap:10px}.speech-sheet h2{font-size:25px}.speech-sheet p{font-size:15px;line-height:1.4}}
@media(prefers-reduced-motion:reduce){.panel-enter{animation:none}.slate-meter i{transition:none}}
/* Magnetic models: readable apparatus, direct controls and an in-slate close view. */
.magnetic-tools{display:flex;gap:9px;flex:none}.slate-page .magnetic-tools button{min-height:30px;padding:4px 9px;font-size:12px;box-shadow:none}.magnetic-player .magnetic-svg{background:#fafaf5;filter:none;border:1px solid #222}.magnetic-player [data-model],.magnetic-player [data-experiment-view]{max-height:300px}.magnetic-player .magnetic-svg{max-height:300px}.magnetic-player svg{touch-action:none}.magnetic-player svg [role=button]{cursor:pointer;outline:none}.magnetic-player svg [role=button]:focus-visible>rect,.magnetic-player svg [role=button]:focus-visible>circle{stroke:#fff;stroke-width:5}.magnetic-player [data-source][aria-pressed=true] circle{fill:#eee;stroke:#eee;stroke-width:5}.trace-actions{display:flex;gap:10px}.slate-player.diagram-focus .activity-intro,.slate-player.diagram-focus .slate-mini-nav{display:none!important}.slate-player.diagram-focus [data-work]>*:not(svg):not([data-model]):not([data-experiment-view]){display:none!important}.slate-player.diagram-focus [data-work]>svg,.slate-player.diagram-focus [data-model],.slate-player.diagram-focus [data-experiment-view],.slate-player.diagram-focus .activity-svg{max-height:none!important;height:100%;flex:1;min-height:0}.slate-player[data-view=prediction] .magnetic-tools,.slate-player[data-view=followup] .magnetic-tools{display:none}
@media(max-width:650px){.magnetic-player [data-model],.magnetic-player [data-experiment-view],.magnetic-player .magnetic-svg{max-height:220px}.magnetic-player .trace-actions button{font-size:12px;min-height:33px;padding:5px 10px}}
@media(max-height:650px){.magnetic-player [data-model],.magnetic-player [data-experiment-view],.magnetic-player .magnetic-svg{max-height:105px}.slate-page .magnetic-tools button{font-size:10px;min-height:25px;padding:3px 7px}.magnetic-player .observation-note p{font-size:12px}.magnetic-player .experiment-stages button{min-height:33px;font-size:10px}}
.slate-layout{grid-template-columns:minmax(0,1fr)}.manga-slate,.slate-stage,.slate-player,.slate-lesson,.slate-player [data-work],.slate-player [data-model],.slate-player [data-experiment-view],.slate-player .activity-svg{min-width:0}.slate-player .activity-svg{max-width:100%}
.manga-slate{grid-template-columns:minmax(0,1fr)}
@media(max-width:350px){.slate-controls{gap:4px;padding-left:6px;padding-right:6px}.slate-controls button{font-size:11px;padding:5px 6px}.slate-controls [data-actions]{gap:4px}.slate-controls [data-back]{width:27px}.slate-controls [data-check]{max-width:51px}.slate-hud{gap:5px}}
/* Choice sets stay together: no option paging, including on phones. */
.slate-player .tap-choices{grid-template-columns:repeat(2,minmax(0,1fr))}.slate-player .tap-choices button{min-height:48px;font-size:16px;padding:12px}.slate-player .tap-match>div:last-child{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}.slate-player .tap-match button{min-height:45px;padding:10px;font-size:15px;overflow-wrap:anywhere}.slate-player[data-type=sequence] .space-picks{grid-template-columns:repeat(2,minmax(0,1fr));align-content:start}.slate-player[data-type=sequence] .space-picks button{position:relative;min-height:50px;padding:12px;font-size:15px}.slate-player[data-type=sequence] .sequence-slots{display:none}.slate-player [data-item]:disabled{opacity:1;background:#222;color:#fff;padding-left:38px!important}.slate-player [data-item][data-position]:disabled:before{content:attr(data-position);position:absolute;left:10px;top:50%;transform:translateY(-50%);border:1px solid #fff;border-radius:50%;width:21px;height:21px;display:grid;place-items:center;font:12px monospace}.slate-player[data-type=sequence] [data-work]{justify-content:center}.slate-player .tap-choices button:only-child{grid-column:1/-1}
@media(max-width:650px){.slate-player .tap-choices{grid-template-columns:1fr;gap:8px}.slate-player .tap-choices button{font-size:14px;min-height:44px;padding:10px}.slate-player .tap-match{flex:0;gap:10px}.slate-player .tap-match>div:last-child{gap:7px}.slate-player .tap-match button{font-size:13px;min-height:44px;padding:9px}.slate-player[data-type=sequence] .space-picks{gap:8px}.slate-player[data-type=sequence] .space-picks button{font-size:13px;min-height:44px;padding:9px}.slate-player .followup-card>p{font-size:13px;line-height:1.35}}
@media(max-height:650px){.slate-player .tap-choices button{font-size:13px;line-height:1.25;padding:8px;min-height:40px}.slate-player .prediction-card h3,.slate-player .followup-card h3{font-size:17px}.slate-player .followup-card>p{font-size:12px;line-height:1.3}.slate-player[data-type=sequence] .space-picks button,.slate-player .tap-match button{font-size:12px;line-height:1.25;padding:7px;min-height:40px}.slate-player[data-type=sequence] .space-picks{gap:7px}}
@media(max-width:650px){.slate-player .tap-match{flex:none;grid-template-columns:minmax(0,1fr)}.slate-player .tap-match>div{min-width:0}}
/* Apparatus actions are always available; observation is checked explicitly. */
.lab-slider-row{display:flex;align-items:center;gap:8px}.lab-slider-row input{flex:1;min-width:0}.slate-page .lab-step{min-height:30px;min-width:33px;padding:1px 8px;font-size:19px;box-shadow:none}.lab-actions{display:flex;gap:7px;flex:none}.slate-page .lab-actions button{flex:1;min-height:35px;padding:6px 9px;font-size:12px;box-shadow:none;line-height:1.15}.magnetic-player [data-model],.magnetic-player [data-experiment-view]{position:relative;touch-action:none;flex:1;min-height:70px}.magnetic-player .lab-hit,.magnetic-player [data-board],.magnetic-player .lab-compass{cursor:pointer}.magnetic-player [data-drag]{cursor:grab}.magnetic-player [data-drag]:active{cursor:grabbing}.magnetic-player .lab-hit:focus-visible{outline:3px dashed #444;outline-offset:4px}.magnetic-player [data-experiment-view] svg[role=button]{cursor:pointer}.magnetic-player .lab-compass [data-needle],.magnetic-player [data-filing]{transform-origin:0 0}.magnetic-player [data-answer-vector]>path,.magnetic-player [data-wires]>path{animation:answer-appear .25s ease-out}.magnetic-player [data-clear-arrow],.magnetic-player [data-clear-wires]{align-self:flex-start;min-height:30px;font-size:12px;padding:4px 10px;box-shadow:none}.magnetic-player .magnetic-tools{gap:6px;flex-wrap:wrap}.magnetic-player .magnetic-tools button{font-size:11px}.magnetic-player [data-work]{gap:7px}.slate-player.diagram-focus [data-work]>.lab-actions{display:flex!important}.motion-paused *{animation-play-state:paused!important}@keyframes answer-appear{from{opacity:0}to{opacity:1}}
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.slate-player button.chosen:hover,.slate-player button.chosen:focus-visible{background:#303030;color:#fff}.magnetic-player .experiment-stages button:not(.chosen){background:#fff;color:#111}
.magnetic-player .lab-hit circle{pointer-events:all}
@media(max-height:650px){.magnetic-player[data-type=experiment] [data-experiment-view],.magnetic-player[data-type=experiment] .magnetic-svg{max-height:140px}}
/* Solids experiments: apparatus, readouts and controls share one slate. */
.slate-player[data-type="mechanics"] [data-work]{min-height:0;flex:1;display:flex;flex-direction:column;padding:0!important}
.mechanics-lab{height:100%;min-height:0;display:flex;flex-direction:column;gap:8px;color:#171717}
.mechanics-lab [data-mech-graphic]{flex:1;min-height:80px;display:flex;justify-content:center;background:repeating-linear-gradient(0deg,transparent 0 29px,#16161608 30px),#f8f8f5;border:1px solid #aaa;overflow:hidden;touch-action:none}
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.mech-caption{font-size:12px!important;line-height:1.2!important;margin:0!important;text-align:center;color:#555}
.mech-enlarged .mech-controls,.mech-enlarged .mech-meter,.mech-enlarged .mech-caption,.mech-enlarged .mech-buttons button:not([data-mech-zoom]){display:none!important}
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/* Continuous apparatus motion: readable geometry, stable handles, explicit reference shapes. */
.mechanics-lab .mech-reference{fill:none;stroke:#666;stroke-dasharray:6 5;stroke-width:2;opacity:.65}.mechanics-lab .mech-grid{opacity:.28}.mechanics-lab .mech-dimension{stroke-dasharray:3 3;opacity:.75}.mechanics-lab .mech-unload{stroke-dasharray:7 4}.mechanics-lab .mech-divider{opacity:.2}.mechanics-lab svg{max-height:none!important;align-self:stretch}.mechanics-lab [data-mech-graphic]{align-items:center}.mechanics-lab svg [data-grip]:focus-visible{outline:none}.mechanics-lab svg [data-grip]:focus-visible circle{stroke-width:6}.slate-page .mech-buttons button{padding:5px 8px;font-size:12px;min-height:32px}.mech-enlarged .mechanics-lab svg{max-height:none!important}.mechanics-lab [data-mech-graphic][data-moving=true]{border-color:#181818}.slate-page .mech-controls button{min-height:34px;min-width:34px;padding:0}.mech-caption{min-height:15px}
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/* Illustrated textbook pages: prose, colour-coded concepts, no dialogue balloons. */
.theory-spread{display:grid;grid-template-columns:minmax(0,1fr);min-height:0;align-items:center;gap:30px;flex:1}.theory-spread.with-visual{grid-template-columns:minmax(0,1fr) minmax(0,1.15fr)}.theory-prose{border-left:4px solid #167d75;padding:8px 0 8px 22px;min-width:0}.theory-prose p{font-size:clamp(18px,2vw,26px);line-height:1.65;margin:0;color:#28232c}.theory-key{text-decoration-thickness:2px;text-underline-offset:4px;font-weight:650}.key-0{color:#126f69}.key-1{color:#80538c}.key-2{color:#a64a38}.theory-figure{margin:0;min-height:0;max-height:100%;display:flex;flex-direction:column;gap:7px;align-items:center}.theory-figure img{display:block;width:100%;max-height:340px;object-fit:contain;min-height:0;border:1px solid #c5beb4}.theory-figure figcaption{font-size:12px;line-height:1.35;color:#685c6b}.theory-figure svg{height:100%;width:100%;max-height:320px;filter:none!important;color:#25212a}.slate-illustration.theory-figure{max-height:340px}.mechanics-lab{position:relative}.curve-inspector{position:absolute;z-index:5;left:8px;right:8px;top:8px;padding:15px 35px 15px 16px;background:#fffaf0;border:2px solid #725887;box-shadow:3px 3px 0 #725887;max-width:530px;color:#332536}.curve-inspector strong{font-size:17px;color:#765080}.curve-inspector p{font-size:15px!important;line-height:1.45!important;margin:8px 0 0!important}.curve-inspector button{position:absolute;right:3px;top:3px;min-height:27px;padding:2px 7px}.mechanics-lab [data-curve-info]{cursor:help}.mechanics-lab [data-curve-info]:focus-visible{outline:2px solid #765080}.semi-lab [data-semi-graphic]{flex:1;min-height:80px;background:#faf8f1;border:1px solid #b7adb9;display:flex;align-items:center}.semi-lab [data-semi-graphic] svg{cursor:default}.slate-player[data-type=semiconductor] [data-work]{flex:1;min-height:0;padding:0!important}.mech-enlarged [data-semi-zoom]{display:block!important}.mech-enlarged .semi-lab .mech-buttons button:not([data-semi-zoom]){display:none!important}.semi-lab .mech-meter{font-size:12px}.theory-figure [role=button]{pointer-events:none}
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.curve-inspector{top:auto;bottom:0}
.slate-player[data-type=optics] [data-work]{flex:1;min-height:0}.optics-lab{height:100%;min-height:0;display:flex;flex-direction:column;gap:8px}.optics-instruction{font-size:18px;font-weight:650;color:#725088;background:#f0e7f4;border-left:4px solid #79518e;padding:8px 12px}.optics-graphic{flex:1;min-height:100px;background:#faf8ee;border:1px solid #b9b1ba;display:flex}.optics-graphic svg{width:100%;height:100%;min-height:0;touch-action:manipulation}.optics-graphic [role=button]{cursor:pointer}.optics-graphic [role=button]:focus-visible{outline:2px solid #126d6a}.optics-quiz{display:flex;gap:8px;flex-wrap:wrap}.optics-quiz:empty{display:none}.optics-quiz button{flex:1;min-height:36px;font-size:14px;padding:7px}.optics-feedback{font-size:14px!important;line-height:1.35!important;margin:0!important;color:#9c453b;min-height:18px}.optics-tools{display:flex;gap:7px}.optics-tools button{font-size:12px;padding:5px 10px;min-height:32px}.optics-enlarged .activity-intro{display:none}.optics-enlarged .optics-quiz,.optics-enlarged .optics-feedback,.optics-enlarged .optics-tools button:not([data-optics-zoom]){display:none}.optics-drawn-ray{stroke-dasharray:900;stroke-dashoffset:0;animation:draw-ray .6s ease-out}@keyframes draw-ray{from{stroke-dashoffset:900}to{stroke-dashoffset:0}}
@media(max-width:650px){.optics-instruction{font-size:14px;padding:6px 8px}.optics-quiz button{font-size:12px;min-height:36px;padding:5px}.optics-tools{gap:5px}.optics-tools button{font-size:11px;padding:4px 6px}.optics-feedback{font-size:12px!important;line-height:1.3!important}.slate-player[data-type=optics] .activity-intro h2{font-size:16px}.optics-lab{gap:6px}}
@media(max-height:650px){.optics-instruction{font-size:12px}.optics-tools button{font-size:10px;min-height:28px;padding:3px 5px}.optics-quiz button{font-size:11px;min-height:30px}.optics-feedback{font-size:11px!important;min-height:14px}.slate-player[data-type=optics] .activity-intro h2{font-size:14px;line-height:1.25}.optics-graphic{min-height:95px}}
@media(prefers-reduced-motion:reduce){.optics-drawn-ray{animation:none}}
.slate-illustration.theory-figure:has([data-mech-canvas]),.slate-illustration.theory-figure:has(svg[aria-label$="interactive model"]){background:#faf8f0;filter:none;border-color:#bbb}
.optics-quiz[data-placement=true]{display:grid;grid-template-columns:repeat(3,minmax(0,1fr))}.optics-quiz [data-precision]{border-color:#9b85aa;background:#f3edf5}.optics-quiz [data-precision]:hover{background:#e0cfea}
.optics-graphic g[clip-path="url(#optic-clip)"]{pointer-events:none}
.optics-graphic text{pointer-events:none}
/* Leave enough space for long titles and the teacher's review row. */
.slate-lesson{max-width:1000px}.theory-prose p{font-size:clamp(18px,1.65vw,24px);line-height:1.5}.theory-figure{height:100%;min-height:0}.theory-figure img{flex:1;max-height:min(340px,calc(100% - 40px));object-fit:contain}.theory-figure figcaption{flex:0 0 auto}
@media(max-width:650px){.theory-prose p{font-size:17px;line-height:1.5}.theory-figure img{max-height:min(220px,calc(100% - 35px))}}
@media(max-height:650px){.theory-prose p{font-size:15px;line-height:1.4}.theory-figure img{max-height:135px}}
/* Full Light chapter: one physical apparatus and one reasoning step at a time. */
.slate-player[data-type=light]{gap:7px}.slate-player[data-type=light] [data-work]{gap:0;flex:1;min-height:0}.slate-player[data-type=light] .activity-intro h2{font-size:clamp(15px,1.6vw,21px);line-height:1.2}.light-lab{height:100%;min-height:0;display:flex;flex-direction:column;gap:7px;color:#29222e}.light-step{display:flex;gap:10px;align-items:center;border-left:4px solid #805194;background:#f0e8f2;padding:7px 10px}.light-step>span{font:11px monospace;white-space:nowrap;color:#805194}.light-step strong{font-size:17px;line-height:1.25}.light-apparatus{flex:1;min-height:70px;display:flex;background:#fffaf0;border:1px solid #b6adb7;overflow:hidden}.light-apparatus svg{width:100%;height:100%;min-height:0;overflow:hidden;filter:none!important}.light-apparatus [data-light-hit]{cursor:pointer}.light-apparatus [data-light-hit]:focus-visible{outline:3px solid #805194}.light-apparatus text{pointer-events:none}.light-readout{font:600 12px/1.25 monospace;text-align:center;min-height:15px;color:#137b76}.light-controls{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.light-controls label{font-size:13px;min-width:0}.light-controls label:only-child{grid-column:1/-1}.light-controls label>span{display:flex;justify-content:space-between;gap:4px}.light-controls label>div{display:flex;gap:7px;align-items:center}.light-controls input{width:100%;min-width:0;accent-color:#137b76}.light-controls select{width:100%;min-height:35px;color:#29222e;background:#fffaf0;border:1px solid #805194;font:inherit}.light-controls button{min-height:30px!important;padding:2px 8px!important;min-width:30px}.light-choices{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:7px}.light-choices button{min-height:42px;font-size:15px;line-height:1.25;padding:7px 10px;text-align:left}.light-choices button:only-child{grid-column:1/-1;text-align:center}.light-choices button[aria-pressed=true]{border-color:#137b76;background:#e0ede8}.light-feedback{font-size:13px;line-height:1.3;color:#994833;min-height:0}.light-feedback:empty{display:none}.light-tools{display:flex;gap:7px;justify-content:center}.light-tools button{min-height:30px;font-size:12px;padding:4px 8px}.light-enlarged .light-step,.light-enlarged .light-controls,.light-enlarged .light-choices,.light-enlarged .light-feedback,.light-enlarged .light-readout,.light-enlarged .light-tools button:not([data-light-zoom]){display:none!important}.slate-player[data-type=light]:has(.light-enlarged) .activity-intro{display:none}.light-lab [hidden]{display:none!important}
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@media(max-height:650px){.light-lab{gap:4px}.light-step strong{font-size:12px}.light-step{padding:4px 6px}.light-choices button{font-size:11px;min-height:29px;padding:4px 6px}.light-controls button{min-height:26px!important}.light-tools button{min-height:25px;font-size:10px}.light-feedback{font-size:10px;line-height:1.2}.light-readout{font-size:9px}.light-apparatus{min-height:65px}.light-controls select{min-height:27px}.slate-player[data-type=light] .activity-intro h2{font-size:12px}.light-choices:has([data-light-state]){grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(prefers-reduced-motion:reduce){.light-apparatus animateMotion,.light-apparatus animate{display:none}}

/* Keep touch targets stationary; allow the apparatus to shrink on compact phones. */
.slate-player button:hover{transform:none}
@media(max-height:650px){.optics-graphic{min-height:65px}}