@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;600;700&family=Space+Grotesk:wght@400;500;600;700&display=swap');
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.lesson-desc{font-size:16px}.hold{font-size:14px}.tip{font-size:14px}.step strong{font-size:13px}.level strong{font-size:14px}.quick-card strong{font-size:14px}.btn{font-size:14px}.controls .btn{font-size:13px}.heading p{font-size:15px}.algorithm-card p{font-size:13px}.algorithm-card .card-title span{font-size:12px}.main{margin:0 auto}.lesson-pane{min-width:0}.workspace{min-width:0}.controls{flex-wrap:wrap}.lesson-footer{flex-wrap:wrap}@media(max-width:1150px){.step strong{font-size:12px}.level strong{font-size:13px}}@media(max-width:650px){.level strong{font-size:10px}.heading p{font-size:14px}.step strong{font-size:12px}.tip{font-size:13px}.controls .btn{font-size:12px}.controls{flex-wrap:nowrap}.lesson-desc{font-size:16px}}

/* Pair-building lessons and the beginner cross progression. */
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/* Recognise the cube before choosing an algorithm. */
.case-picker{margin:0 0 28px}.case-picker-heading{margin-bottom:22px}.case-picker-heading h2{font-size:21px}.case-picker-heading p{font-size:13px;color:var(--muted);margin-top:7px;max-width:660px}.case-picker-group+ .case-picker-group{margin-top:25px}.case-picker-group h3{font-size:14px;margin-bottom:12px}.case-diagrams{display:grid;grid-template-columns:repeat(auto-fill,minmax(135px,1fr));gap:12px}.case-diagram{display:flex;flex-direction:column;align-items:center;justify-content:flex-start;padding:12px 10px 15px;border:1px solid var(--line);border-radius:10px;background:#fff;transition:background .15s,border-color .15s;text-align:center}.case-diagram:hover{border-color:#8eaa50;background:#f7fbeF}.case-diagram.active{border-color:#9dbb60;background:#eef5df}.case-diagram svg{width:100%;max-width:155px;height:145px;margin-bottom:9px}.case-diagram span{font-size:13px;font-weight:600}.case-diagram small{font-size:11px;color:var(--muted);margin-top:5px}@media(max-width:600px){.case-diagrams{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.case-diagram svg{height:135px}}

/* Guided solving: compact decisions, then a focused walkthrough. */
.solve-heading{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:22px}.solve-heading h1{font-size:28px;margin-top:6px}.solve-heading p{color:var(--muted);font-size:14px}.step-menu{position:relative;flex-shrink:0}.step-menu summary{cursor:pointer;padding:10px;border:1px solid var(--line);border-radius:7px;font-size:13px;background:white}.step-menu nav{position:absolute;right:0;top:45px;z-index:5;min-width:230px;background:#fff;padding:8px;box-shadow:0 8px 30px #15203020;border-radius:9px}.step-menu button{display:block;text-align:left;width:100%;padding:12px;font-size:14px}.step-menu [aria-current]{background:var(--lime);border-radius:5px}.solve-section{scroll-margin-top:18px;padding:20px;border:1px solid var(--line);border-radius:12px;background:#fff;margin-bottom:18px}.solve-section.current{border-color:#aec878}.flow-title{display:flex;align-items:center;justify-content:space-between;gap:10px}.flow-title h2{font-size:21px}.flow-hint{font-size:14px;color:#626e7d;margin:10px 0 16px;line-height:1.5}.choose-label{font-family:inherit;font-size:13px;font-weight:500;margin:14px 0 10px;color:#67717e}.section-actions{display:flex;align-items:center;flex-wrap:wrap;gap:10px;margin-top:16px}.situation-help{margin-top:14px}.situation-help details{border-top:1px solid var(--line);padding:11px 0;font-size:13px}.situation-help summary{cursor:pointer;font-weight:500}.situation-help p{color:#68717f;margin-top:8px;max-width:650px}.solve-bottom{display:flex;justify-content:space-between;gap:12px}.result-check{margin-top:20px;border-top:1px solid var(--line);padding-top:15px}.result-check summary{cursor:pointer;font-size:14px;font-weight:600}.result-check p{font-size:14px;color:#67717e}.result-diagram{max-width:180px;margin:10px auto}.result-diagram svg{width:100%}.solve-finish{max-width:600px;margin:40px auto}.solve-finish p{margin:20px 0}.solve-finish button{margin:5px}.visual-filters{display:flex;gap:8px;overflow-x:auto;margin:12px 0 18px;padding:4px}.visual-filters button{flex:0 0 105px;border:1px solid var(--line);border-radius:8px;padding:8px;font-size:11px;min-height:44px}.visual-filters button.active{background:var(--lime)}.visual-filters svg{height:65px;width:100%}.pattern-options{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.pattern-option{background:#fff;border:1px solid var(--line);border-radius:12px;padding:18px;text-align:left}.pattern-option svg{width:100%;height:160px}.pattern-option strong,.pattern-option span{display:block;margin-top:12px}.pattern-option span{font-size:12px;color:#727e8c}.algorithm-grid{display:block}.library-section{margin-bottom:28px}.library-section h2{font-size:20px;margin-bottom:14px}.case-diagrams{grid-template-columns:repeat(auto-fill,minmax(125px,1fr))}.case-diagram svg{height:115px}.method-mobile{display:none}.flash-actions{flex-wrap:wrap}.flash-actions button{min-height:44px}.modal-body .below{margin-top:16px}.modal-body .below .tip{display:none}.modal-head{position:sticky;top:0;background:#fff;z-index:5}.modal-head button{min-width:64px;min-height:44px;font-size:14px}.lesson-desc{font-size:13px;line-height:1.5}.hold{font-size:13px}.cube-pane{min-height:300px}.cube-stage{min-height:190px}.cube-stage svg{max-width:260px}.library-toolbar .filters{flex-wrap:wrap}.foot button{font-size:11px}.library-toolbar details{font-size:13px}.library-toolbar details summary{cursor:pointer;padding:10px}.library-toolbar details .filters{margin-top:8px}.move-help{position:relative}.turn[data-move-help]{cursor:pointer}
@media(max-width:700px){
 header{height:auto;padding:10px 14px;gap:10px;flex-wrap:wrap}.brand{font-size:23px}.notation{padding:7px 10px;font-size:12px}.topnav{order:3;width:100%;justify-content:space-between;gap:10px;height:36px}.topnav button{font-size:12px}.layout{display:block;min-height:0}.layout>aside{display:none}.main{padding:14px 12px 24px}.method-mobile{display:flex;align-items:center;justify-content:space-between;margin-bottom:16px;font-size:12px;color:var(--muted);gap:10px}.method-mobile select{border:1px solid var(--line);padding:8px;border-radius:6px;background:white;color:var(--ink);max-width:210px;min-height:40px}.solve-heading{margin-bottom:14px}.solve-heading h1{font-size:24px;letter-spacing:-.7px}.solve-heading .eyebrow{font-size:10px;letter-spacing:1px}.step-menu summary{font-size:12px;padding:9px}.solve-section{padding:13px;margin-bottom:14px}.flow-title h2{font-size:18px;letter-spacing:-.4px}.flow-title .pill{font-size:10px}.flow-hint{font-size:13px;margin:8px 0 12px}.case-diagrams{grid-template-columns:repeat(3,minmax(0,1fr));gap:7px}.case-diagram{padding:7px 4px 10px;min-width:0;border-radius:8px}.case-diagram svg{height:82px;margin-bottom:5px;width:100%}.case-diagram span{font-size:11px;line-height:1.3;overflow-wrap:anywhere}.case-diagram small{font-size:10px}.choose-label{margin:10px 0 8px}.section-actions{gap:8px}.section-actions .btn{white-space:normal}.situation-help{margin-top:10px}.pattern-options{grid-template-columns:1fr}.pattern-option{display:grid;grid-template-columns:90px 1fr;align-items:center;gap:0 15px;padding:10px}.pattern-option svg{height:85px;grid-row:span 2}.pattern-option strong{font-size:14px}.pattern-option span{margin-top:4px}.heading{margin-bottom:14px;display:block}.heading h1{font-size:25px}.heading .eyebrow,.heading .path-label{display:none}.heading p{font-size:13px;margin-top:6px}.library-toolbar{gap:10px;margin:12px 0}.library-toolbar>.btn{font-size:12px;padding:9px}.segmented button{font-size:11px;padding:8px}.filters input{min-width:0;max-width:180px}.library-section h2{font-size:18px}.foot{margin-top:20px}.visual-filters button{flex-basis:88px}.visual-filters svg{height:50px}
 dialog{width:100%;max-width:100%;height:100dvh;max-height:100dvh;margin:0;border:0;border-radius:0;padding:0}dialog .modal-head{padding:9px 14px;gap:10px}dialog .modal-head strong{font-size:13px}dialog .modal-body{padding:10px 12px 24px}dialog .workspace,.workspace{display:flex;flex-direction:column;border:0;border-radius:0;overflow:visible}dialog .cube-pane,.cube-pane{min-height:0;padding:8px;border:0;border-radius:9px}.cube-stage{min-height:0;height:150px}.cube-stage svg{max-height:150px;width:auto;max-width:100%}.pane-top{font-size:10px}.pane-top .pill{padding:3px 6px;font-size:10px}.cube-caption{font-size:10px;margin:0}.cube-view-buttons{margin-top:4px}.cube-view-buttons button{font-size:11px;padding:7px 10px;min-height:32px}.lesson-pane{padding:12px 0 0}.lesson-kicker{font-size:10px;margin-bottom:6px}.lesson-pane h2{font-size:21px}.lesson-desc{margin:7px 0 10px;font-size:12px}.hold{padding:9px 11px;margin-bottom:10px;font-size:12px;line-height:1.45}.hold strong{font-size:10px}.alg-row{gap:4px;margin:8px 0 12px;min-height:0}.turn{min-width:29px;height:32px;font-size:15px;padding:0 6px}.controls{position:sticky;bottom:0;z-index:4;background:#fff;padding:10px 0 calc(10px + env(safe-area-inset-bottom));border-top:1px solid var(--line);gap:6px;flex-wrap:nowrap;margin-top:0}.controls .btn{min-height:44px;padding:8px 10px;font-size:12px}.controls .btn.primary{flex:1}.controls .btn.icon{width:38px;flex-shrink:0}.lesson-footer{font-size:11px;margin-top:6px}.lesson-footer select{font-size:11px}.result-check{margin-top:12px}.modal-bottom{font-size:11px;padding:12px}.pair-phases{padding:9px;margin-bottom:10px}.pair-phases p{font-size:12px}.pair-phases button{font-size:11px}.below{align-items:flex-start;flex-wrap:wrap;gap:12px}.below .tip{max-width:100%;font-size:12px}.flash-top{flex-wrap:wrap;gap:8px}.flash-top select{max-width:240px}.flash-actions{gap:6px}.flash-actions .btn{font-size:12px;padding:9px 12px}
}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}
@media(max-width:700px){dialog .modal-body .cube-pane{min-height:0}dialog .modal-body .cube-stage{min-height:0;height:145px;flex:none}dialog .modal-body .cube-stage svg{height:145px;max-height:145px;width:auto}dialog .lesson-pane>p[style]{display:none}dialog .lesson-kicker{display:none}}
.move-help{padding:10px;background:#f4f6f8;border-radius:7px;font-size:12px;margin-bottom:12px}.move-comparison{display:flex;align-items:center;justify-content:center;gap:15px}.move-comparison svg{height:100px;width:100px}.pattern-options{grid-template-columns:repeat(auto-fit,minmax(190px,1fr))}@media(max-width:700px){.pattern-options{grid-template-columns:1fr}}

/* Page-owned navigation: methods in Learn, sets in Library and Practice. */
.layout{display:block;min-height:calc(100vh - 82px)}
.main{max-width:1180px;padding:32px 36px}
.learn-intro{display:flex;justify-content:space-between;align-items:center;gap:28px;margin-bottom:24px}
.learn-intro h1{font-size:32px;margin-top:8px}.learn-intro p{color:var(--muted);font-size:14px;margin-top:8px}
.method-picker{display:flex;flex-direction:column;gap:7px;font-size:12px;font-weight:600;color:#576174;max-width:100%;margin-bottom:20px}
.learn-intro .method-picker{margin:0;flex:0 1 335px}
.method-picker select{max-width:100%;min-width:0;min-height:44px;border:1px solid #ccd2dc;border-radius:8px;background:#fff;color:var(--ink);padding:10px;font-size:13px}
.solve-route{display:flex;flex-wrap:wrap;gap:8px;margin:0 0 28px;padding-bottom:22px;border-bottom:1px solid var(--line)}
.solve-route button{display:flex;align-items:center;gap:8px;padding:9px 12px;border:1px solid var(--line);background:white;border-radius:8px;font-size:12px;min-height:44px;text-align:left}
.solve-route button span,.look-route button span{display:grid;place-items:center;border-radius:50%;width:23px;height:23px;background:#edf0f3;font-size:11px;flex-shrink:0}
.solve-route [aria-current="step"]{background:var(--ink);color:white;border-color:var(--ink)}
.solve-route [aria-current="step"] span{background:var(--lime);color:var(--ink)}
.solve-heading h2{margin-top:6px;font-size:26px}.solve-heading .text-btn{min-height:44px}
.look-route{display:flex;gap:8px;margin-bottom:12px;flex-wrap:wrap}
.look-route button{display:flex;align-items:center;gap:8px;flex:1;min-width:150px;min-height:48px;padding:10px 14px;background:#eceff3;border:1px solid transparent;border-radius:8px;text-align:left;font-size:13px}
.look-route [aria-current="step"]{background:#edf4df;border-color:#a9c46d;font-weight:600}.look-route [aria-current="step"] span{background:#dafa80}
.focused-lesson{padding:26px;outline-offset:4px}.focused-lesson .case-diagrams{grid-template-columns:repeat(auto-fill,minmax(130px,1fr));max-width:100%}
.focused-lesson .case-diagrams:has(>button:nth-child(2)):not(:has(>button:nth-child(4))){grid-template-columns:repeat(3,minmax(0,1fr));max-width:600px}
.focused-lesson .case-diagrams:not(:has(>button:nth-child(2))){grid-template-columns:minmax(0,190px)}
.starting-hold{font-size:13px;line-height:1.6;background:#f3f5f8;border-radius:7px;padding:12px 14px;margin-bottom:22px;color:#566274}.starting-hold strong{color:#252f3e;margin-right:8px}
.choose-heading{display:flex;align-items:baseline;justify-content:space-between;gap:12px;margin:22px 0 12px}.choose-heading h3{font-size:17px}.choose-heading span{font-size:12px;color:var(--muted)}
.step-check{display:grid;grid-template-columns:1fr auto;align-items:center;gap:12px 24px;margin-top:24px;padding:20px;background:#f0f5e7;border-radius:10px}.step-check h3{font-size:16px}.step-check p{font-size:13px;line-height:1.6;color:#536347;margin-top:6px;max-width:600px}.step-check small{grid-column:1/-1;font-size:12px;color:#60714e}.step-check .btn{white-space:normal;min-height:44px}
.cross-start{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;padding:0;list-style:none;counter-reset:cross;margin:20px 0}.cross-start li{counter-increment:cross;position:relative;padding-left:30px}.cross-start li:before{content:counter(cross);position:absolute;left:0;top:0;width:22px;height:22px;border-radius:50%;background:#e8efda;text-align:center;line-height:22px;font-size:12px}.cross-start strong{font-size:14px}.cross-start p{font-size:13px;line-height:1.6;color:#67717f;margin-top:5px}
.solve-bottom{align-items:center;flex-wrap:wrap}.solve-bottom button{min-height:44px}.practice-label{font-size:13px;font-weight:600;color:#576174}.flash-top select{max-width:280px}
@media(max-width:700px){
 .main{padding:20px 12px 24px}.learn-intro{display:block;margin-bottom:16px}.learn-intro h1{font-size:27px}.learn-intro p{font-size:13px}.learn-intro .method-picker{margin-top:18px}.method-picker select{width:100%}
 .solve-route{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px;margin-bottom:20px;padding-bottom:18px}.solve-route button{font-size:11px;padding:8px;gap:6px;min-width:0}.solve-route button span{width:21px;height:21px}
 .solve-heading{align-items:flex-start}.solve-heading h2{font-size:23px}.solve-heading .text-btn{max-width:108px;font-size:11px;text-align:right}
 .look-route{gap:6px;display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}.look-route button{font-size:11px;min-width:0;padding:9px 8px;gap:6px}
 .focused-lesson{padding:14px}.focused-lesson .case-diagrams{grid-template-columns:repeat(3,minmax(0,1fr))}.focused-lesson .case-diagrams:not(:has(>button:nth-child(2))){grid-template-columns:minmax(0,130px)}
 .starting-hold{font-size:12px;padding:10px;margin-bottom:16px}.starting-hold strong{display:block;margin-bottom:3px}.choose-heading{display:block;margin:16px 0 10px}.choose-heading h3{font-size:16px}.choose-heading span{display:block;margin-top:4px;font-size:11px}
 .step-check{display:block;padding:14px;margin-top:20px}.step-check .btn{margin-top:14px;width:100%;font-size:13px}.step-check small{display:block;margin-top:10px}.cross-start{grid-template-columns:1fr;gap:14px}.cross-start p{margin-top:3px}.solve-bottom{gap:4px}.solve-bottom .text-btn{font-size:11px}.flash-top select{max-width:100%}
}
@media(max-width:700px){
 .learn-intro .eyebrow,.learn-intro>div>p{display:none}.learn-intro h1{font-size:24px;margin:0}.learn-intro .method-picker{margin-top:12px;display:flex;flex-direction:row;align-items:center;gap:10px;font-size:11px}.learn-intro .method-picker select{flex:1;width:0;font-size:12px}
 .solve-route{display:flex;flex-wrap:nowrap;overflow-x:auto;padding:0 0 12px;margin-bottom:16px;scrollbar-width:thin}.solve-route button{flex:0 0 auto;max-width:160px}.solve-route button span{width:20px;height:20px}
 .solve-heading{margin-bottom:12px}.focused-lesson .starting-hold{padding:8px 10px}.starting-hold strong{display:inline}.choose-heading{margin-top:12px}
}
@media(max-width:700px){.topnav{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:4px;height:auto;min-height:42px}.topnav button{min-width:0;min-height:42px;padding:4px 2px;text-align:center;font-size:11px;line-height:1.35}}
/* PLL recognition gives side stickers and fixed centres the space they need. */
.finder-tabs{display:flex;gap:8px;flex-wrap:wrap;margin:18px 0}.finder-tabs button{padding:12px 16px;border:1px solid var(--line);border-radius:8px;background:white;min-height:44px;font-size:13px}.finder-tabs [aria-pressed=true]{background:var(--ink);color:white}.finder-note{font-size:14px;color:#596678;background:#eef2f6;padding:14px;border-radius:8px;margin-bottom:18px}
.finder-question{border:1px solid var(--line);background:white;padding:24px;border-radius:12px}.finder-question h2{font-size:24px;margin:8px 0}.finder-question p{font-size:14px;color:#606d7e;margin:10px 0;max-width:760px}.finder-answers{display:flex;flex-wrap:wrap;gap:8px}.clue-example{display:flex;gap:5px;margin:18px 0 24px}.clue-example span{width:42px;height:42px;border:1px solid #596577;border-radius:5px}.clue-example .marked{border-bottom:5px solid #253a1e}
.recognition-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:14px}.recognition-grid .case-diagram svg{height:180px;max-width:220px}.recognition-grid strong{font-size:13px}.case-diagrams:has(.pll-sides){grid-template-columns:repeat(auto-fill,minmax(190px,1fr))}.case-diagram .pll-sides{height:170px;max-width:210px}.cube-stage:has(.pll-sides){min-height:250px}.cube-stage .pll-sides{height:250px;max-height:none;width:300px;max-width:100%}.cube-view-buttons{flex-wrap:wrap}.colour-entry{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;margin-top:24px}.colour-entry fieldset{border:1px solid var(--line);border-radius:8px;padding:16px;text-align:center;min-width:0}.colour-entry legend{font-size:13px;font-weight:600}.entry-row{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:6px}.entry-row select{width:100%;min-height:48px;font-size:12px;border:1px solid #758091;border-radius:5px;color:#172333;padding:3px}.entry-centre{width:48px;height:40px;margin:12px auto 3px;border:1px solid #758091;border-radius:5px;display:grid;place-items:center}.colour-entry small{font-size:11px;color:#667385}.entry-feedback{font-size:14px;color:#9e392a;margin-top:14px}.matched-case,.match-plan{background:#eef5df;padding:16px;border-radius:8px;margin:15px 0}.match-plan{font-size:13px;line-height:1.6}.match-plan small{display:block;margin-top:8px;color:#61734c}
@media(max-width:700px){.finder-question{padding:16px}.finder-question h2{font-size:21px}.finder-tabs{gap:6px}.finder-tabs button{font-size:12px;padding:10px;flex:1}.recognition-grid,.case-diagrams:has(.pll-sides),.focused-lesson .case-diagrams:has(.pll-sides){grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.recognition-grid .case-diagram svg,.case-diagram .pll-sides{height:auto;width:100%;max-width:210px}.recognition-grid strong{font-size:12px}.colour-entry{grid-template-columns:1fr;gap:16px}.entry-row select{font-size:14px}.cube-stage:has(.pll-sides),dialog .modal-body .cube-stage:has(.pll-sides){height:235px;min-height:235px}.cube-stage .pll-sides,dialog .modal-body .cube-stage .pll-sides{height:230px;max-height:230px;width:auto}.finder-note{font-size:12px}.section-top{gap:10px}.section-top h3{font-size:15px}}
.pll-view-controls{display:flex;gap:6px;margin:16px 0 8px}.pll-view-controls button{min-height:44px;padding:10px 18px;border:1px solid var(--line);border-radius:7px;background:white;font-size:13px}.pll-view-controls [aria-pressed=true]{background:var(--ink);color:white}.pll-legend{font-size:12px;color:#626e7d;line-height:1.6;margin:0 0 16px;max-width:720px}.case-diagram .pll-sides,.recognition-grid .case-diagram .pll-sides{height:auto;aspect-ratio:1;max-width:230px;width:100%}.cube-stage:has(.pll-sides){min-height:300px}.cube-stage .pll-sides{height:300px;width:300px}.result-diagram:has(.pll-sides){max-width:260px}@media(max-width:700px){.cube-stage:has(.pll-sides),dialog .modal-body .cube-stage:has(.pll-sides){height:265px;min-height:265px}.cube-stage .pll-sides,dialog .modal-body .cube-stage .pll-sides{height:260px;max-height:260px;width:260px}.cube-caption{line-height:1.5}.pll-view-controls button{flex:1}.pll-legend{font-size:12px}}

.clue-examples{display:flex;flex-wrap:wrap;gap:20px;margin:16px 0 24px}.clue-examples .clue-example{margin:0 0 8px}.clue-examples strong{font-size:13px}.clue-summary{padding-left:20px;font-size:13px;line-height:1.8;color:#536173}

.flash-mode{margin-bottom:20px}.flash-mode [aria-pressed=true]{background:var(--ink);color:white}.typing-row .answer-box{width:72px;min-width:60px;border:2px solid #526376;text-align:center;font-size:22px;color:var(--ink);background:white;border-radius:10px;min-height:56px}.typing-row .answer-box:focus{outline:3px solid #a5b9d4;outline-offset:2px}.typing-row .answer-correct{background:#dcfce7;color:#166534;border:2px solid #16a34a}.typing-row .answer-wrong{background:#fee2e2;color:#991b1b;border:2px solid #dc2626}.answer-pending{opacity:.45}.typing-feedback{font-size:14px;margin:12px 0;min-height:40px}.typing-player .cube-view-buttons,.typing-player [data-control=play],.typing-player [data-control=next],.typing-player [data-control=reveal],.typing-player [data-cadence]{display:none}

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