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@media(max-width:650px){.feature-tag{font-size:.75rem}.math-tile small{font-size:.65rem}.math-caption{font-size:.75rem}.math-tile small{display:none}.feature h2{font-size:1.3rem}.feature-copy{padding:18px}.thumb{aspect-ratio:16/9}.card-foot{flex-wrap:wrap;gap:3px}.stat span{font-size:.75rem}}
/* Grade selection and extra practice extend the original theme. */
select{font:inherit}select:focus-visible{outline:3px solid #ef991e;outline-offset:3px}.breadcrumb{display:flex;align-items:center;gap:8px}.breadcrumb select{border:1px solid #c5d1ed;border-radius:9px;background:#f4f7ff;color:var(--navy);font-weight:800;padding:9px 28px 9px 10px;min-height:44px}.breadcrumb span{margin:0 3px}.grade-switch{display:flex;gap:12px;margin:0 0 24px}.grade-option{display:flex;align-items:center;justify-content:space-between;gap:25px;flex:1;max-width:220px;padding:13px 17px;min-height:54px;border:1px solid var(--line);background:#fff;color:var(--navy);border-radius:13px}.grade-option span{font-size:.875rem;color:#58637c}.grade-option strong{font-size:1.05rem}.grade-option.active{background:var(--navy);border-color:var(--navy);color:#fff}.grade-option.active span{color:#d7e1ff}.extra-count{color:#526079;font-size:.875rem;padding-top:9px}.practice-callout{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:25px;background:#ecf4da;border:1px solid #d7e5bd;border-radius:18px}.practice-callout h2{font-size:1.35rem;margin:0 0 8px}.practice-callout p{margin:0}.practice-callout .btn{flex-shrink:0}.practice-link{margin-top:10px}.practice-progress{display:block;margin-top:5px}.result-library{display:block;color:var(--blue);margin-top:18px;text-decoration:underline}.column-example{display:grid;font-size:2rem;line-height:1.35;text-align:right;font-weight:800;min-width:150px;padding:0 20px}.column-example strong{border-top:3px solid var(--blue);color:var(--blue)}.fraction-example{display:flex;gap:3px;padding:10px 0}.fraction-example span{width:22px;height:70px;background:#eef2ff;border:1px solid #a6b3d1;border-radius:4px}.fraction-example .blue{background:var(--blue);border-color:var(--blue)}.fraction-example .lime{background:var(--lime);border-color:#99ba50}.math-tile .equation{color:var(--navy);max-width:none}.lesson-tabs{flex-wrap:wrap;gap:12px 22px}.brand small{display:none}.card-foot{font-size:.875rem}.card-category{font-size:.8125rem}.brand-mark{transform:none}.topbar{min-height:88px;height:auto;padding-top:12px;padding-bottom:12px}
@media(max-width:700px){.grade-switch{gap:7px}.grade-option{padding:12px 9px;gap:5px;flex-direction:column}.grade-option strong{font-size:1rem}.grade-option span{font-size:.8125rem}.practice-callout{flex-direction:column;align-items:stretch}.breadcrumb strong,.breadcrumb>span,.breadcrumb>label{display:none}.breadcrumb{display:flex!important}.topbar{gap:8px;flex-wrap:wrap;padding:12px 16px}.topbar-right{margin-left:auto}.breadcrumb select{padding-right:20px}.mobile-brand{font-size:1.05rem}.progress-chip{font-size:.8125rem;padding:8px 10px}.lesson-tabs button{font-size:.875rem}.math-tile{max-width:100%;min-width:0;padding:22px}.fraction-example span{width:21px}.progress-row{align-items:flex-start;flex-wrap:wrap}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{transition:none!important;animation:none!important}}
/* A growing learning path: concrete objects for younger learners, models for older. */
.grade-switch{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:10px}.grade-option{max-width:none;gap:5px;flex-direction:column;align-items:flex-start}.next-mission{background:var(--blue);color:white;padding:28px 32px;border-radius:22px;display:grid;grid-template-columns:minmax(0,1fr) 210px;gap:35px;margin:0 0 26px}.next-mission .eyebrow{color:#dfebff}.next-mission h2{font-size:1.65rem;margin:0 0 9px}.next-mission p{color:#e3eaff;margin-bottom:18px}.mission-actions{display:flex;gap:10px;flex-wrap:wrap}.journey-meter{border-left:1px solid #ffffff50;padding-left:30px;display:flex;flex-direction:column;justify-content:center}.journey-meter>strong{font-size:2.8rem;line-height:1.15}.journey-meter>strong span{font-size:1.25rem;font-weight:500}.journey-meter>span{font-size:.9rem}.journey-meter small{font-size:.85rem;color:#e3eaff}.journey-track{height:7px;background:#ffffff40;border-radius:4px;overflow:hidden;margin:15px 0}.journey-track i{display:block;height:100%;background:var(--lime)}.play-lesson-link{display:flex;align-items:center;gap:18px;background:#edf5dc;border-radius:14px;padding:18px;margin-bottom:25px}.play-lesson-link>span{font-size:2rem;color:#427315}.play-lesson-link strong{display:block;font-size:1.15rem}.play-lesson-link small{display:block;margin-top:5px;font-size:.9rem;color:#405534}.play-lesson-link>b{margin-left:auto}.play-heading{max-width:850px;margin-bottom:24px}.play-heading h1{font-size:2rem;margin-bottom:12px}.play-heading>p{font-size:1.2rem;line-height:1.55;max-width:780px}.play-meta{display:flex;gap:15px;align-items:center;justify-content:space-between;color:var(--muted);font-size:.9rem}.listen-btn{background:#fff;border:1px solid var(--line);color:var(--blue);padding:10px 14px;border-radius:10px;font:inherit;font-weight:800;min-height:44px}.play-board{background:#fff;border:1px solid var(--line);border-radius:23px;padding:30px;max-width:880px;box-shadow:0 6px 0 #e6ebf6}.play-control{border:2px solid #d0daed;border-radius:12px;background:#f7f9fe;color:#192348;min-width:48px;min-height:48px;padding:10px 15px;font:inherit;font-weight:800;cursor:pointer}.play-control:hover:not(:disabled){border-color:#244de8;background:#edf2ff}.play-control[aria-pressed=true]{background:#244de8;border-color:#244de8;color:white;box-shadow:0 3px 0 #152d88}.play-control:disabled{cursor:default;opacity:.45}.play-control:focus-visible,.play-answer:focus-visible,.listen-btn:focus-visible{outline:3px solid #e4951c;outline-offset:4px}.play-actions{display:flex;justify-content:space-between;gap:15px;margin-top:27px;padding-top:22px;border-top:1px solid var(--line)}.play-actions [data-play=check],.play-actions [data-play=next]{background:#244de8;color:#fff;border-color:#244de8;min-width:150px}.play-feedback{font-size:1rem;line-height:1.6;margin-top:15px;color:#6e4814}.play-feedback:empty{display:none}.play-feedback.success{color:#286b38}.hint-box{background:#fff7de;border:1px solid #ecdba6;padding:18px;border-radius:12px;margin-top:18px}.hint-box p{margin:5px 0 0}.play-success{text-align:center;padding:28px 5px}.play-success h2{font-size:1.8rem}.earned-stars{display:block;font-size:2.6rem;color:#c18a13;letter-spacing:10px;margin-bottom:12px}.play-success .btn{margin:6px}.model-result{display:block;font-size:1.8rem;font-weight:800;text-align:center;color:#244de8;margin:18px 0}.model-figure{max-width:600px;margin:auto}.model-figure svg{display:block;width:100%;height:auto;max-height:340px;overflow:visible}.stepper{display:flex;align-items:center;justify-content:center;gap:12px;margin:12px 0}.stepper>span{min-width:145px}.stepper output{min-width:50px;text-align:center;font-weight:800;font-size:1.2rem}.stepper .play-control{font-size:1.5rem;padding:3px 12px}.play-choices{display:grid;gap:12px;grid-template-columns:repeat(2,minmax(0,1fr));margin:22px 0}.play-choices .play-control{min-height:64px;font-size:1.1rem;text-align:left;padding:15px 19px}.count-board{display:grid;grid-template-columns:repeat(5,1fr);gap:12px;max-width:470px;margin:20px auto}.count-board .play-control{aspect-ratio:1;padding:14px;background:white}.count-dot{display:block;border:2px dashed #aabbd9;border-radius:50%;width:100%;height:100%;min-height:25px}.count-dot.filled{background:#244de8;border:2px solid #244de8}.count-board .play-control[aria-pressed=true]{border-color:#244de8;background:#eef3ff;box-shadow:none}.place-board{display:flex;justify-content:center;gap:8px;flex-wrap:wrap;margin:20px 0}.place-column{flex:1;min-width:65px;max-width:125px;background:#f0f4fe;border:1px solid #d8e2f5;border-radius:15px;text-align:center;padding:14px 6px}.place-column>span{display:block;font-weight:800;font-size:.9rem;color:#526480;overflow-wrap:anywhere}.place-column>strong{display:block;font-size:2.4rem;color:#244de8;padding:8px 0}.place-column .play-control{margin:2px;min-width:44px;padding:5px 10px}.mini-beads{display:flex;flex-wrap:wrap;justify-content:center;gap:3px;margin-top:9px;min-height:14px}.mini-beads i{width:10px;height:10px;background:#789e32;border-radius:50%}.array-board{display:grid;gap:6px;max-width:420px;margin:20px auto}.array-board span{border-radius:50%;background:#244de8;aspect-ratio:1;max-width:48px;min-width:10px}.fraction-board{display:grid;grid-template-columns:repeat(var(--pieces),1fr);gap:5px;max-width:640px;margin:25px auto}.fraction-board .play-control{border-radius:5px;min-width:0;padding:0;min-height:120px}.fraction-board.hundred{gap:4px;max-width:550px}.fraction-board.hundred .play-control{min-height:44px;aspect-ratio:1}.shape-hunt{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;max-width:530px;margin:20px auto}.shape-hunt .play-control{padding:15px}.shape-hunt svg{width:100%;display:block}.shape-hunt .play-control[aria-pressed=true]{background:#e4edff}.directions-board{display:grid;grid-template-columns:repeat(3,80px);grid-template-rows:80px 80px;gap:12px;justify-content:center;margin:30px auto}.directions-board .play-control{font-size:2.4rem}.directions-board .play-control:nth-child(1){grid-area:1/2}.directions-board .play-control:nth-child(2){grid-area:2/1}.directions-board .play-control:nth-child(3){grid-area:2/3}.directions-board .play-control:nth-child(4){grid-area:2/2}.play-toolbar{display:flex;justify-content:center;gap:20px;margin:20px 0}.order-slots{display:grid;gap:10px;padding:20px;background:#f3f7e9;border-radius:12px;min-height:75px;color:#334b1c}.order-slots>span{display:block;border-bottom:1px solid #ccddb0;padding-bottom:8px;font-size:1.1rem}.play-input-label{display:block;text-align:center;font-weight:800;margin:20px 0 10px}.play-answer{display:block;border:2px solid #bdcde9;border-radius:12px;padding:15px;font:inherit;font-size:1.4rem;text-align:center;width:min(100%,320px);margin:auto;color:#192348}.balance-board{display:flex;justify-content:center;align-items:center;gap:25px;background:#f1f6ff;padding:35px 15px;border-radius:16px;font-size:2rem}.balance-board b{display:inline-block;border-bottom:3px solid #244de8;min-width:55px;text-align:center;color:#244de8}.code-lock{display:flex;gap:16px;justify-content:center;margin:12px 0 25px}.code-lock span{background:#edf2fc;border:2px solid #c9d6eb;border-radius:15px;width:70px;height:70px;display:grid;place-items:center;font-size:1.8rem;font-weight:800;color:#667b9f}.code-lock .unlocked{background:#e5f3c9;border-color:#7d9f3c;color:#356422}.cube-net{display:grid;grid-template-columns:repeat(4,minmax(0,90px));grid-template-rows:repeat(3,90px);gap:3px;justify-content:center;margin:25px auto}.cube-net .play-control{font-size:.875rem;padding:5px;border-radius:4px}.cube-net small{display:block;font-size:.85rem;margin-top:5px}.model-caption{text-align:center;color:#53627e}.data-table{margin:10px auto;border-collapse:collapse;font-size:.95rem}.data-table caption{font-size:.85rem;color:var(--muted);margin:8px}.data-table td,.data-table th{padding:8px 18px;border:1px solid var(--line)}.curriculum-table{overflow:auto}.curriculum-table table{border-collapse:collapse;width:100%}.curriculum-table th,.curriculum-table td{text-align:left;padding:12px;border-bottom:1px solid var(--line)}body[data-grade="1"] .play-heading>p,body[data-grade="2"] .play-heading>p{font-size:1.35rem}body[data-grade="1"] .play-control,body[data-grade="2"] .play-control{min-height:54px}body[data-grade="1"] .next-mission{background:#285fc8}body[data-grade="2"] .next-mission{background:#356443}body[data-grade="3"] .next-mission{background:#2d5971}body[data-grade="5"] .next-mission{background:#4d4291}.lesson-card h3{min-height:0}.card-copy{gap:3px}.lesson-grid{align-items:stretch}.extra-count{font-size:.8125rem}.play-success{animation:gentle-in .3s ease-out}@keyframes gentle-in{from{opacity:.5;transform:translateY(7px)}to{opacity:1;transform:none}}
@media(max-width:900px){.grade-option{padding:12px 6px}.grade-option span{font-size:.8rem}.next-mission{padding:24px;gap:20px;grid-template-columns:minmax(0,1fr) 150px}.journey-meter{padding-left:20px}.next-mission h2{font-size:1.45rem}.play-board{padding:23px}.play-meta{flex-wrap:wrap}.play-heading h1{font-size:1.8rem}}
@media(max-width:650px){.grade-switch{gap:5px}.grade-option{align-items:center;padding:12px 3px;min-height:70px}.grade-option strong{font-size:.9rem}.grade-option span{font-size:.75rem}.next-mission{padding:22px;grid-template-columns:1fr}.journey-meter{border-left:0;border-top:1px solid #ffffff40;padding:15px 0 0;display:grid;grid-template-columns:1fr 1fr;gap:5px 15px;align-items:center}.journey-meter>strong{font-size:1.8rem}.journey-meter>strong span{font-size:1rem}.journey-track{margin:5px 0}.next-mission h2{font-size:1.5rem}.mission-actions .btn{font-size:.875rem}.play-board{padding:18px 14px;border-radius:16px}.play-heading>p{font-size:1.1rem}.play-heading h1{font-size:1.65rem}.play-choices{grid-template-columns:1fr}.play-choices .play-control{font-size:1.05rem}.stepper{gap:8px}.stepper>span{min-width:100px;font-size:.9rem}.play-actions{gap:10px}.play-actions .play-control{font-size:.9rem;min-width:0}.place-column{min-width:58px}.shape-hunt{gap:10px}.shape-hunt .play-control{padding:8px}.fraction-board:not(.hundred) .play-control{min-height:100px}.fraction-board.hundred{gap:3px}.fraction-board.hundred .play-control{min-height:25px}body[data-grade="1"] .fraction-board.hundred .play-control,body[data-grade="2"] .fraction-board.hundred .play-control{min-height:25px}.cube-net{grid-template-columns:repeat(4,minmax(0,66px));grid-template-rows:repeat(3,66px)}.cube-net .play-control{font-size:.75rem;min-height:0}.balance-board{font-size:1.6rem;gap:15px}.count-board{gap:8px}.count-board .play-control{padding:10px}.model-result{font-size:1.5rem}.play-lesson-link{gap:12px;padding:15px}.play-lesson-link small{font-size:.85rem}.intro-row h1{font-size:1.9rem}.lesson-card .card-category{font-size:.75rem}.lesson-card .extra-count{font-size:.75rem}}
@media(max-width:650px){.fraction-board.hundred{grid-template-columns:repeat(5,minmax(0,1fr));max-height:360px;overflow-y:auto;padding:4px}.fraction-board.hundred .play-control{min-height:44px;aspect-ratio:1}}
/* An encouraging companion and a short, personal review path. */
.brand{gap:8px;font-size:1.2rem}.brand-owl{width:58px;height:58px;object-fit:contain;flex-shrink:0}.result-owl{display:block;object-fit:contain;margin:0 auto 15px}.review-badge{font-size:.8rem;background:#d7f58b;color:#294719;border-radius:20px;padding:2px 7px;margin-left:auto;line-height:1.5}.review-badge[hidden]{display:none}.review-callout{display:flex;align-items:center;gap:16px;border:1px solid #d3dfef;background:#fff;border-radius:16px;padding:20px 23px;margin:0 0 26px}.review-callout strong,.review-callout div>span{display:block}.review-callout strong{margin-bottom:4px;font-size:1.1rem}.review-callout div>span{color:#58637c;font-size:.95rem;line-height:1.5}.review-callout>b{margin-left:auto;color:var(--blue);font-size:1.4rem}.review-symbol{background:#eaf0ff;border-radius:14px;padding:5px 14px;color:var(--blue);font-size:2rem}.result-actions{display:flex;flex-wrap:wrap;gap:10px;justify-content:center}.next-lesson-link{display:block;text-align:left;padding:19px 22px;background:#eef5df;border:1px solid #cfdfae;border-radius:14px;margin:24px 0 0}.next-lesson-link>span{display:block;color:#466326;font-size:.8125rem;letter-spacing:.5px;margin-bottom:7px}.next-lesson-link strong{font-size:1.1rem;line-height:1.4}.review-empty img{object-fit:contain;margin-bottom:15px}.review-empty p{max-width:520px;margin:0 auto 24px}.review-row .mission-actions{flex-shrink:0}.mobile-nav a.active{color:var(--blue)}
@media(max-width:1200px){.brand{font-size:1.1rem}.brand-owl{width:49px;height:49px}.review-row{align-items:flex-start;flex-wrap:wrap}}
@media(min-width:651px) and (max-width:900px){.brand{font-size:1rem;gap:5px}.brand-owl{width:42px;height:42px}.main-nav a{font-size:.875rem;padding-left:7px;padding-right:7px;gap:7px}}
@media(max-width:650px){.mobile-brand{display:flex;align-items:center;gap:6px;white-space:nowrap;font-size:1.05rem;min-height:44px}.mobile-brand img{object-fit:contain;flex-shrink:0}.mobile-nav a{font-size:.8125rem;min-height:44px;display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:4px;padding:5px 3px}.mobile-nav{padding-top:5px;padding-bottom:max(5px,env(safe-area-inset-bottom))}.mobile-nav .review-badge{margin-left:0;font-size:.75rem;padding:1px 5px}.review-callout{padding:16px;gap:12px}.review-symbol{padding:5px 10px}.review-callout strong{font-size:1rem}.review-callout div>span{font-size:.9rem}.review-row .mission-actions{width:100%}.next-lesson-link{padding:17px}.result-actions .btn{width:100%;justify-content:center}}
/* The owl's guided practice: readable models, optional help and calm progression. */
.tutor-entry{display:flex;align-items:center;gap:16px;padding:20px;background:#eaf0ff;border:1px solid #ccdaf7;border-radius:16px;margin-bottom:18px}.tutor-entry img{object-fit:contain;flex-shrink:0}.tutor-entry strong,.tutor-entry span{display:block}.tutor-entry strong{font-size:1.1rem;color:#192348}.tutor-entry span{font-size:.95rem;line-height:1.5;color:#50617f;margin-top:4px}.tutor-entry>b{margin-left:auto;color:#244de8;font-size:1.4rem}.tutor-result-link{display:block;margin-top:20px;color:var(--blue);font-weight:800;text-decoration:underline}.tutor-heading{display:flex;align-items:center;gap:24px;margin:16px 0 26px;max-width:950px}.tutor-heading>img{object-fit:contain;flex-shrink:0}.tutor-heading h1{font-size:1.9rem;margin-bottom:10px}.tutor-heading p{margin-bottom:0;color:#58637c;font-size:1.05rem}.tutor-board{max-width:850px;padding:30px}.tutor-status{display:flex;gap:12px;justify-content:space-between;align-items:center;font-weight:800}.tutor-level{background:#eef5df;color:#365824;padding:8px 12px;border-radius:12px;font-size:.875rem}.tutor-question-row{display:flex;align-items:flex-start;gap:18px;margin:28px 0 20px}.tutor-question-row h2{font-size:1.35rem;line-height:1.5;flex:1;margin:0;outline:none}.tutor-question-row .listen-btn{flex-shrink:0}.tutor-model{max-width:480px;margin:20px auto 24px}.tutor-model svg{display:block;width:100%;height:auto;max-height:280px}.tutor-model-steps{background:#f2f6fc;border-radius:12px;padding:18px 22px;line-height:1.6}.tutor-model-steps p:last-child{margin-bottom:0}.tutor-dots{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:12px;max-width:360px;margin:auto}.tutor-dots>span{grid-column:1/-1;text-align:center;padding:20px}.tutor-dot{height:54px;border:2px solid #d4e0f4;background:#f2f6ff;border-radius:12px;padding:12px}.tutor-dot span{display:block;border-radius:50%;background:#244de8;width:26px;height:26px;margin:auto}.tutor-dot[aria-pressed=true]{background:#d7f58b;border-color:#5f832b}.tutor-dot[aria-pressed=true] span{background:#365824}.tutor-symbol{text-align:center;font-size:3.6rem;font-weight:800;color:#244de8;line-height:1.5}.tutor-equation{display:flex;justify-content:center;align-items:center;gap:13px;font-size:1.5rem;font-weight:800;padding:22px 5px;flex-wrap:wrap}.tutor-equation>span{background:#eff4fd;border:1px solid #ccd9ef;padding:10px 14px;border-radius:12px}.tutor-array{display:grid;grid-template-columns:repeat(var(--columns),minmax(0,1fr));gap:8px;max-width:320px;margin:auto}.tutor-array i{aspect-ratio:1;border-radius:50%;background:#244de8;max-width:32px}.tutor-fraction{display:grid;grid-template-columns:repeat(var(--columns),minmax(0,1fr));gap:4px;max-width:460px;margin:auto}.tutor-fraction i{height:70px;background:#f2f6ff;border:2px solid #90a8d0;border-radius:5px}.tutor-fraction .filled{background:#244de8;border-color:#244de8}.tutor-help{padding-top:22px;margin-top:25px;border-top:1px solid var(--line)}.tutor-help-top{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.tutor-help-top img{object-fit:contain}.tutor-easier{background:none;border:none;color:#526486;text-decoration:underline;min-height:44px;font-size:.9rem}.tutor-hint{padding:18px 20px;background:#f2f6ff;border-radius:12px;margin-top:14px}.tutor-hint>strong{color:#244de8}.tutor-hint>p{margin:7px 0 0;line-height:1.6}.tutor-hint .tutor-model{margin-bottom:0}.tutor-feedback:not(:empty){margin-top:22px}.tutor-audio-status{margin:16px 0 0}.tutor-audio-status:empty{display:none}.tutor-finish{text-align:center}.tutor-finish>img{object-fit:contain;margin-bottom:16px}.tutor-finish .mission-actions{justify-content:center}.tutor-summary{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin:24px 0}.tutor-summary>div{background:#f1f5ff;border-radius:14px;padding:20px 12px}.tutor-summary strong,.tutor-summary span{display:block}.tutor-summary strong{font-size:2rem;color:#244de8}.tutor-summary span{font-size:.9rem;margin-top:5px}.tutor-place{display:flex;flex-wrap:wrap;justify-content:center;gap:8px}.tutor-place span{background:#eaf0ff;border:1px solid #9eb6df;border-radius:8px;padding:12px 16px;font-weight:800}.tutor-bar-model{padding:12px 5px}.tutor-bar-row{height:38px;display:flex;gap:2px;margin:10px 0}.tutor-bar-row i{display:block;background:#244de8;border-radius:4px}.tutor-bar-row i:nth-child(2){background:#b7d96f}.tutor-bar-caption{display:flex;justify-content:space-between;color:#405475;font-weight:800;font-size:.95rem}.tutor-bar-model>p{margin:8px 0;font-size:.95rem}
@media(max-width:650px){.tutor-heading{gap:14px;align-items:flex-start}.tutor-heading>img{width:62px;height:62px}.tutor-heading h1{font-size:1.5rem}.tutor-heading p{font-size:1rem}.tutor-heading .eyebrow{font-size:.75rem;letter-spacing:.5px}.tutor-board{padding:21px 16px}.tutor-question-row{flex-direction:column;gap:12px;margin-top:20px}.tutor-question-row h2{font-size:1.25rem}.tutor-status{font-size:.9rem}.tutor-level{font-size:.8125rem;padding:8px}.tutor-entry{padding:16px;gap:12px}.tutor-entry img{width:49px;height:49px}.tutor-entry strong{font-size:1rem}.tutor-entry span{font-size:.9rem}.tutor-equation{font-size:1.25rem;gap:8px}.tutor-equation>span{padding:8px 10px}.tutor-help-top{gap:8px}.tutor-help-top img{width:36px;height:36px}.tutor-help-top .btn{font-size:.95rem}.tutor-hint{padding:16px 13px}.tutor-summary{gap:8px}.tutor-summary>div{padding:16px 7px}.tutor-summary span{font-size:.8125rem}.tutor-dots{gap:8px}.tutor-dot{min-width:0;padding:10px 5px}.tutor-dot span{width:23px;height:23px}.tutor-finish .btn{width:100%;justify-content:center}body[data-grade="1"] .tutor-question-row h2,body[data-grade="2"] .tutor-question-row h2{font-size:1.35rem}}

.tutor-shape-group{display:flex;gap:12px;align-items:center}.tutor-shape-group svg{width:50%;min-width:0}

.tutor-bar-row i.removed{background:repeating-linear-gradient(135deg,#e6ebf3 0 6px,#b0bbcc 6px 9px);border:1px dashed #657690}

/* A warm notebook, with an individual accent for each school year. */
:root{--bg:#faf9f5;--line:#e6e6e9;--muted:#626d83;--navy:#252d4b;--soft:#f0eefa;--blue:#5551be}
body[data-grade="1"]{--blue:#285fc0;--soft:#edf3ff}
body[data-grade="2"]{--blue:#276b50;--soft:#eaf5ed}
body[data-grade="3"]{--blue:#20657f;--soft:#eaf4f8}
body[data-grade="4"]{--blue:#5551be;--soft:#f0eefa}
body[data-grade="5"]{--blue:#873e68;--soft:#f8edf3}
body{background:var(--bg);-webkit-font-smoothing:antialiased}
.sidebar{border-right:1px solid #ece9e2;background:#fffefa;padding-top:24px;overflow-y:auto}
.brand{justify-content:center}
.brand-owl{width:78px;height:78px;filter:drop-shadow(0 5px 7px #2932490c)}
.class-card{margin-top:24px;border-radius:18px;background:var(--soft);border-color:transparent}
.class-number{background:#fff;color:var(--blue);border-radius:12px;min-width:45px;text-align:center}
.main-nav a{min-height:48px;transition:background .16s,color .16s}
.main-nav a.active{background:var(--soft);color:var(--blue)}
.main-nav a.active span{color:var(--blue)}
.sidebar-note{border-radius:18px;background:var(--soft);margin-top:auto;padding:20px 16px 12px}
.note-symbol{background:#fff3ca;box-shadow:0 3px 0 #e8dba533}
.sidebar-bottom{margin-top:20px}
.topbar{background:#fffefa;border-bottom:1px solid #ece9e2}
.progress-chip{background:var(--soft);border-color:transparent;color:var(--blue);padding:11px 16px}
#grade-select{border-radius:10px;min-height:40px;background:#fff}
main{padding-top:36px}
.intro-row{margin-bottom:27px}
.intro-row h1{font-size:clamp(1.9rem,3.2vw,2.7rem);letter-spacing:-1px;max-width:760px}
.intro-row p{font-size:1.05rem;color:#626d83}
.eyebrow{letter-spacing:1.1px}
.grade-switch{gap:12px;margin-bottom:26px}
.grade-option{position:relative;min-height:82px;border:1px solid #e5e5eb;border-bottom-width:3px;border-radius:17px;padding:15px 18px;transition:transform .16s,border-color .16s,background .16s}
.grade-option strong{font-size:1.15rem}
.grade-option span{font-size:.82rem}
.grade-option:hover{transform:translateY(-2px);border-color:var(--blue)}
.grade-option.active{background:var(--blue);border-color:var(--blue);box-shadow:0 5px 0 #252d4b12;color:white}
.grade-option.active span{color:#fff;opacity:.85}
body .next-mission{position:relative;isolation:isolate;display:grid;grid-template-columns:minmax(0,1fr) 218px;gap:32px;align-items:center;padding:32px 34px;border-radius:26px;background:var(--blue);border:1px solid #ffffff25;box-shadow:0 9px 24px #3034550d;overflow:hidden}
body[data-grade] .next-mission{background:var(--blue)}
.next-mission::before{content:"";position:absolute;inset:0;z-index:-1;background-image:radial-gradient(#ffffff15 1px,transparent 1px);background-size:22px 22px;pointer-events:none}
.next-mission .eyebrow{color:#fff;opacity:.85}
.next-mission h2{font-size:clamp(1.6rem,2.4vw,2.15rem);line-height:1.25;max-width:640px;color:white;margin-bottom:12px}
.next-mission p{max-width:540px;color:#fff;opacity:.9;line-height:1.65}
.mission-actions{gap:10px}
.mission-actions .btn{min-height:46px}
.mission-side{display:flex;flex-direction:column;align-items:center;position:relative}
.mission-owl{display:block;width:150px;height:150px;object-fit:contain;margin:-8px 0 -13px;z-index:1;filter:drop-shadow(0 5px 0 #ffffff15)}
.journey-meter{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;width:100%;border:1px solid #ffffff45;border-radius:19px;background:#ffffff15;padding:16px 20px 15px;text-align:center}
.journey-meter>strong{font-size:2.25rem;line-height:1.1;color:#fff}
.journey-meter>strong span{font-size:1.1rem}
.journey-meter>span,.journey-meter small{color:#fff}
.journey-track{width:100%;height:7px;margin:8px 0 5px;background:#ffffff38}
.journey-track i{border-radius:8px;background:#dbefab}
.search-wrap input{border:1px solid #e1e2e8;border-radius:16px;min-height:58px;box-shadow:0 3px 0 #29324903}
.section-heading{margin:30px 0 19px;align-items:baseline}
.section-heading h2{font-size:1.5rem}
.filter-bar{gap:8px;margin-bottom:24px}
.filter{background:#fff;border:1px solid #e6e6eb;border-radius:12px;padding:10px 14px;min-height:42px;color:#58637a}
.filter.active{background:var(--soft);color:var(--blue);border-color:var(--blue)}
.lesson-grid{gap:22px}
.lesson-card{border-radius:21px;border:1px solid #e4e5eb;border-bottom:3px solid #e2e4ec;box-shadow:0 4px 12px #29324904}
.lesson-card:hover{transform:translateY(-4px);border-color:var(--blue);box-shadow:0 12px 25px #2932490d}
.thumb{height:auto;aspect-ratio:16/9;background:var(--soft);border-bottom:1px solid #ebeaf2}
.thumb img{transition:transform .25s}
.lesson-card:hover .thumb img{transform:scale(1.025)}
.thumb .small-play{width:34px;height:34px;bottom:12px;left:14px;border:1px solid #ffffff80;box-shadow:0 2px 5px #00000015;color:var(--blue)}
.thumb .duration{padding:5px 9px;border-radius:8px;background:#252d4be8}
.card-copy{padding:20px}
.card-category{color:var(--blue);letter-spacing:.65px;font-size:.7rem;margin-bottom:10px}
.lesson-card h3{font-size:1.1rem;line-height:1.42;margin-bottom:16px}
.card-foot{padding-top:14px;border-color:#ececf1}
.card-foot .arrow{display:grid;place-items:center;width:29px;height:29px;border-radius:9px;background:var(--soft);color:var(--blue)}
.extra-count{line-height:1.6;color:#5f6a80}
.btn{border-radius:13px;min-height:46px;box-shadow:0 3px 0 #252d4b12;transition:transform .16s,box-shadow .16s}
.btn:hover{box-shadow:0 5px 0 #252d4b12}
.btn.secondary{border-color:#dfe2e9;background:#fff}
.btn.lime{background:#e0efb4;color:#28384a}
.panel,.play-board{border-radius:23px;border-color:#e1e3ed;box-shadow:0 5px 18px #28344d04}
.back-link{display:inline-flex;align-items:center;min-height:40px;margin-bottom:18px;font-weight:700;color:#626d83}
.tutor-heading{max-width:930px;gap:22px;margin:4px 0 26px}
.tutor-heading>img{width:104px;height:104px;filter:drop-shadow(0 5px 5px #2932490a)}
.tutor-heading h1{font-size:clamp(1.5rem,2.4vw,2.1rem)}
.tutor-heading p{max-width:610px;line-height:1.6}
.tutor-board{max-width:900px;padding:32px;border-top:4px solid var(--blue)}
.tutor-status{color:#59657d;font-size:.9rem}
.tutor-level{background:var(--soft);color:var(--blue);border:1px solid #252d4b0b;border-radius:24px;padding:9px 14px}
.quiz-progress{gap:8px}
.quiz-progress span{height:8px;background:#eceef5}
.tutor-question-row{margin:26px 0 24px;align-items:center}
.tutor-question-row h2{font-size:1.48rem;line-height:1.5;color:var(--navy)}
.listen-btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:46px;border:1px solid #dcdfee;border-bottom-width:3px;border-radius:13px;background:var(--soft);color:var(--blue);font-size:.9rem;white-space:normal}
.tutor-question-row .listen-btn::before{content:"♪";font-size:1.3rem;line-height:1}
.answer-list{gap:13px}
.answer{min-height:66px;border:1px solid #dfe3ee;border-bottom-width:3px;border-radius:15px;padding:15px 18px;transition:border-color .15s,background .15s,transform .15s}
.answer .letter{width:34px;height:34px;border-radius:10px;background:#f1f3f8;color:#64708b}
.answer:not(:disabled):hover{transform:translateY(-1px);background:var(--soft);border-color:var(--blue)}
.answer.correct{background:#edf8ef;border-color:#378657;color:#185030}
.answer.wrong{background:#fff3e8;border-color:#bb7738;color:#754312}
.answer.correct .letter{background:#d6eddd;color:#185030}
.answer.wrong .letter{background:#f7dfc8;color:#754312}
.tutor-help{background:#fffcf2;border:1px solid #ece4cc;border-radius:16px;padding:18px;margin-top:27px}
.tutor-help-top{gap:12px}
.tutor-help-top img{width:48px;height:48px}
.tutor-help-top .btn{box-shadow:none;background:#fff;border-color:#ddd7c6}
.tutor-hint{background:#fff;border:1px solid #e8e7df;border-radius:13px}
.tutor-hint>strong{color:var(--blue)}
.tutor-easier{color:#62694e}
.tutor-entry{background:var(--soft);border-color:#252d4b12;border-radius:18px;padding:22px}
.tutor-entry:hover,.play-lesson-link:hover{box-shadow:0 5px 16px #29324908}
.feedback{background:var(--soft);border-radius:16px}
.play-actions [data-play=check],.play-actions [data-play=next]{background:var(--blue);border-color:var(--blue);border-bottom:3px solid #252d4b28;border-radius:13px}
.play-heading h1{font-size:clamp(1.8rem,2.8vw,2.35rem)}
.play-heading>p{max-width:790px;font-size:1.15rem;line-height:1.7}
.lesson-tabs{gap:20px;flex-wrap:wrap}
.lesson-tabs button{min-height:48px}
.video-wrap{border-radius:22px;box-shadow:0 7px 22px #25304b12}
.chapters{border-radius:20px}
.chapter:hover,.chapter.active{background:var(--soft);color:var(--blue)}
.stat{border-radius:21px;border-top:3px solid var(--blue)}
.tutor-summary>div{background:var(--soft);border:1px solid #252d4b09}
.tutor-summary strong{color:var(--blue)}
.mobile-nav{background:#fffefa;border-top:1px solid #e4e1d9;box-shadow:0 -4px 16px #29324906}
body[data-grade="1"] .tutor-question-row h2,body[data-grade="2"] .tutor-question-row h2{font-size:1.55rem}
@media(min-width:1600px){.lesson-grid{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:1100px){body .next-mission{grid-template-columns:minmax(0,1fr) 170px;gap:22px;padding:28px}.mission-owl{width:125px;height:125px}.journey-meter{padding:16px 12px}.lesson-grid{gap:17px}.card-copy{padding:18px}.grade-option{padding:14px 10px}.grade-option strong{font-size:1rem}.tutor-question-row{flex-direction:column;align-items:flex-start;gap:16px}}
@media(max-width:900px){.brand-owl{width:66px;height:66px}.grade-switch{gap:8px}.grade-option{align-items:center}.grade-option span{font-size:.75rem}.sidebar-note{padding:16px 10px 10px}.tutor-board{padding:26px}.tutor-heading>img{width:84px;height:84px}}
@media(max-width:650px){main{padding:24px 17px 32px}.topbar{padding:0 17px}.progress-chip{padding:8px 11px}.intro-row h1{font-size:1.95rem}.intro-row p{font-size:.98rem}.grade-switch{gap:6px}.grade-option{min-height:75px;padding:12px 4px;border-radius:13px}.grade-option strong{font-size:.94rem}.grade-option span{font-size:.75rem}body .next-mission{grid-template-columns:1fr;padding:25px 23px;gap:20px;border-radius:22px}.next-mission h2{font-size:1.7rem}.next-mission .mission-actions{display:grid;grid-template-columns:1fr}.next-mission .btn{width:100%;justify-content:center}.mission-side{display:grid;grid-template-columns:95px minmax(0,1fr);gap:10px;align-items:center}.mission-owl{width:105px;height:105px;margin:0}.journey-meter{display:grid;grid-template-columns:1fr;gap:3px;text-align:left;align-items:start;padding:13px 16px}.journey-meter>strong{font-size:1.65rem}.journey-meter>span{font-size:.82rem}.journey-meter small{font-size:.77rem}.journey-track{margin:5px 0}.section-heading{margin-top:25px}.section-heading h2{font-size:1.3rem}.section-heading>span{font-size:.78rem}.lesson-grid{gap:16px}.card-copy{padding:18px}.lesson-card h3{min-height:0}.thumb{height:auto}.tutor-heading{gap:14px;margin-bottom:21px;align-items:center}.tutor-heading>img{width:72px;height:72px}.tutor-heading .eyebrow{font-size:.75rem;letter-spacing:.6px}.tutor-heading h1{font-size:1.5rem}.tutor-heading p{font-size:.94rem}.tutor-board{padding:23px 17px;border-radius:20px}.tutor-status{align-items:flex-start;font-size:.8rem;gap:8px}.tutor-level{font-size:.75rem;padding:8px 10px}.tutor-question-row h2{font-size:1.3rem}.tutor-question-row{gap:14px;margin:22px 0}.answer{padding:14px;gap:12px;min-height:64px}.tutor-help{padding:14px;margin-top:23px}.tutor-help-top{gap:8px}.tutor-help-top img{width:38px;height:38px}.tutor-help-top .btn{font-size:.9rem;padding:11px 12px}.tutor-easier{font-size:.83rem}.lesson-tabs{gap:14px}.lesson-tabs button{font-size:.88rem}.panel.quiz-box{padding:24px 18px}.tutor-entry{padding:17px}.tutor-summary{gap:8px}.tutor-summary span{font-size:.76rem}body[data-grade="1"] .tutor-question-row h2,body[data-grade="2"] .tutor-question-row h2{font-size:1.4rem}}
@media(max-width:520px){.lesson-grid{grid-template-columns:1fr}.card-category{font-size:.76rem}.lesson-card h3{font-size:1.15rem}.card-foot{font-size:.87rem}.thumb .duration{font-size:.8rem}.section-heading{flex-wrap:wrap;gap:7px}}
@media(prefers-reduced-motion:reduce){.grade-option,.lesson-card,.thumb img,.btn,.answer,.main-nav a{transition:none}.grade-option:hover,.lesson-card:hover,.btn:hover,.answer:not(:disabled):hover{transform:none}.lesson-card:hover .thumb img{transform:none}}