.subject-picker{display:flex;gap:14px;margin:0 0 28px;max-width:720px}.subject-picker button{display:flex;align-items:center;gap:13px;flex:1;padding:17px 22px;text-align:left;border:1px solid #ddd5ed;background:#fffc;border-radius:22px;box-shadow:0 4px 0 #e5dfed;color:#484057}.subject-picker button[aria-pressed=true]{background:#ece3ff;border-color:#b49acc;box-shadow:0 4px 0 #cdb5ed}.subject-picker button>span{flex:1}.subject-picker strong{display:block;font-size:16px}.subject-picker small{display:block;font-size:12px;margin-top:4px;color:#6d627b}.subject-picker .icon{width:25px;height:25px}.subject-picker button>.icon:last-child{width:19px}.math-cover-art{width:100%;height:100%;object-fit:contain;background:#fff;padding:8px;display:block;transition:transform .4s ease}.lesson-tile:hover .math-cover-art{transform:scale(1.02)}.math-page{max-width:1280px;margin:auto}.math-time-note{font-size:12px;color:#746981;text-align:right;margin:0 0 20px}.math-intro{display:grid;grid-template-columns:1.05fr 1fr;align-items:center;gap:40px;padding:20px 0 35px}.math-intro h1{font-size:clamp(36px,4.6vw,64px);line-height:1.08;letter-spacing:-2px;margin:24px 0}.math-intro p{font-size:16px;line-height:1.75}.math-intro .lead{font-size:23px;line-height:1.45;color:#605074}.math-intro-world{position:relative;aspect-ratio:1;border-radius:40px;isolation:isolate}.math-intro-world>img:first-child{width:100%;height:100%;object-fit:cover;border-radius:40px;box-shadow:0 24px 55px #55417522}.math-intro-world>.bio-mira{position:absolute;right:-15px;bottom:-8px;width:46%;height:65%;object-fit:contain;filter:drop-shadow(0 8px 15px #49375322)}.math-intro-world>span{position:absolute;bottom:24px;left:18px;right:35%;padding:16px;background:#fffc;border:1px solid #fff;border-radius:22px;font-size:13px;line-height:1.6;backdrop-filter:blur(12px)}.math-goals{display:grid;gap:11px;margin:24px 0}.math-goals>span{display:flex;gap:10px;font-size:14px;align-items:center}.math-goals .icon{width:20px;height:20px}.math-guide{max-width:820px}.math-playground{padding:28px!important;box-shadow:0 8px 0 #e7dfee,0 20px 45px #5c47790d;overflow:hidden}.math-play-top{display:flex;justify-content:space-between;gap:16px;align-items:center;font-size:12px;line-height:1.6;color:#73617f;margin-bottom:24px}.math-play-top>span:first-child{font-weight:800;display:flex;gap:9px;align-items:center;color:#63458d}.math-play-top .icon{width:22px;height:22px}.math-number-line{width:100%;max-height:300px;display:block;overflow:visible}.line-negative{fill:#efe7ff}.line-positive{fill:#dff1e9}.math-axis{stroke:#81708f;stroke-width:2}.math-tick{stroke:#8d7e99;stroke-width:1}.math-axis-label{font-size:15px;fill:#766781}.math-start{fill:#bc8c52;stroke:white;stroke-width:3}.math-end{fill:#7656bc;stroke:white;stroke-width:3}.math-move{stroke:#8662ce;stroke-width:3;fill:none}#math-arrow path{fill:#8662ce}.math-end-label{font-size:23px;font-weight:800;fill:#6f4eab}.math-equation{display:flex;align-items:center;justify-content:center;gap:16px;flex-wrap:wrap;font-size:38px;font-weight:800;letter-spacing:-1px;margin:14px 0;color:#574364;font-variant-numeric:tabular-nums}.math-equation>span{background:#e7f2e8;padding:7px 16px;border-radius:18px;color:#34624b}.math-equation>small{font-size:18px;font-weight:600;letter-spacing:0;flex-basis:100%;text-align:center}.math-live-description{text-align:center;font-size:14px;color:#786685;line-height:1.6}.math-counter-row{display:flex;align-items:center;justify-content:center;gap:28px;margin:26px 0}.math-counter{text-align:center;margin:22px 0}.math-counter>span{display:block;font-size:13px;font-weight:800;margin-bottom:12px}.math-counter>div{display:flex;align-items:center;justify-content:center;gap:14px}.math-counter output{min-width:42px;font-size:27px;font-weight:800;font-variant-numeric:tabular-nums}.math-counter button{width:48px;min-height:48px;padding:8px!important;background:#eee6fb;border:1px solid #cfbfe4;border-radius:16px;font-size:24px;box-shadow:0 3px 0 #d6c9e9}.math-counter button:disabled{opacity:.42;box-shadow:none;cursor:default}.math-counter small{display:block;font-size:11px;color:#81728b;margin-top:10px}.math-operation,.math-presets{border:0;padding:0}.math-operation legend,.math-presets legend{font-size:13px;font-weight:700;margin-bottom:12px}.math-operation{display:flex;flex-direction:column;gap:8px}.math-operation button,.math-presets button{border:1px solid #ddd2eb;background:#f9f4ff;font-size:13px;min-height:44px;border-radius:14px}.math-operation button[aria-pressed=true],.math-presets button[aria-pressed=true]{background:#e5d5fa;border-color:#a98bc8;box-shadow:0 3px 0 #c6b1df}.math-presets{display:flex;justify-content:center;gap:10px;flex-wrap:wrap;margin:22px 0 8px}.math-presets legend{width:100%;text-align:center}.math-investigate{padding:28px!important;margin:28px 0}.math-investigate h2{font-size:23px}.math-investigate ol,.math-worked ol{padding-left:24px;line-height:1.8;font-size:16px}.math-investigate li,.math-worked li{padding-left:8px;margin:13px 0}.math-investigate>p{font-size:13px;color:#736680}.math-fraction-wholes{max-width:700px;margin:24px auto;display:grid;gap:20px}.math-fraction-wholes strong{display:block;font-size:12px;color:#7f708b;margin:0 0 10px}.math-fraction-grid{display:grid;gap:4px;padding:7px;background:#eae2ef;border-radius:19px;border:1px solid #d3c5e0;height:112px}.math-fraction-grid.parts-2{grid-template-columns:repeat(2,1fr)}.math-fraction-grid.parts-4{grid-template-columns:repeat(4,1fr)}.math-fraction-grid.parts-8{grid-template-columns:repeat(8,1fr)}.math-piece{border:1px solid #d3c7df;background:#faf7fc;border-radius:10px;color:#a48db8;font-size:18px;min-width:0;transition:background .2s,transform .2s,box-shadow .2s!important}.math-piece.filled{background:linear-gradient(145deg,#c8b0ef,#a98bd7);box-shadow:inset 0 3px 1px #e5d3ff,inset 0 -5px 2px #8d6bb33b;color:#fff}.math-piece:hover{transform:translateY(-3px)}.math-piece:focus-visible{outline:3px solid #7960b9;outline-offset:2px}.math-ratio-workspace{display:grid;grid-template-columns:1fr 1fr;gap:24px}.math-paint{display:flex;flex-wrap:wrap;align-content:center;justify-content:center;gap:9px;min-height:145px;padding:20px;background:#f3edf6;border-radius:24px}.math-paint i{width:28px;height:38px;display:block;border-radius:45% 45% 50% 50%;box-shadow:inset 2px 3px 4px #fff9,0 5px 6px #63566d13;transform:rotate(12deg)}.math-paint .blue{background:#8cabe0}.math-paint .yellow{background:#f0cd75}.math-map{width:100%;display:block}.math-map>rect{fill:#eee9e2}.map-path{stroke:#d8c7e4;stroke-width:22;stroke-linecap:round}.map-travelled{stroke:#9d7bc9;stroke-width:12;stroke-linecap:round}.map-building{fill:#a9c9b8;stroke:#dce9df;stroke-width:5}.map-start{fill:#a1715d}.map-rover{fill:#eaa97b;stroke:#fff;stroke-width:4}.math-map text{font-size:15px;fill:#65546f}.math-reading-layout{display:grid;grid-template-columns:minmax(0,1.4fr) minmax(0,1fr);gap:26px;margin-top:24px}.math-reading-layout>*{min-width:0}.math-reading-layout .bio-guide{margin-top:22px}.math-worked{padding:28px!important}.math-worked h2{font-size:25px;line-height:1.3}.math-task-label{font-size:11px;text-transform:uppercase;letter-spacing:.08em;color:#82689d;font-weight:800}.math-callout{background:#edf5ee;padding:18px;border-radius:18px;font-size:14px;line-height:1.75}.math-callout p{margin-bottom:0}.math-question{margin:24px 0}.math-question .bio-choices{max-width:900px}.math-question .bio-choice strong{font-size:17px;line-height:1.5}.math-question .bio-feedback{max-width:900px}.math-question>h2{max-width:900px}.math-article{padding:32px!important;max-width:900px;margin-bottom:28px}.math-article>h2{font-size:30px;line-height:1.3}.math-article>p{font-size:17px;line-height:1.85;max-width:760px}.math-article .article-source{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;font-size:12px;line-height:1.6}.math-ice-example{display:grid;grid-template-columns:repeat(4,1fr);max-width:600px;gap:6px;padding:10px;border-radius:20px;background:#bacfdd}.math-ice-example>span{padding:22px 8px;border-radius:10px;text-align:center;font-size:12px}.math-ice-example .ice{background:#f3f9fc;color:#617f8f;box-shadow:inset 0 -4px #dae9ef}.math-ice-example .water{background:#698eae;color:white}.math-revisit{padding:22px!important;margin-top:20px}.math-revisit p{line-height:1.8}.math-saved{border-left:5px solid #b8a0d5!important}.math-page .bio-child-feedback .bio-chip{margin:4px}.math-page .bio-topline .quiet{font-size:12px}.math-page .primary{white-space:normal}.lesson-direction{display:flex;align-items:center;gap:12px;padding:16px 18px;border-radius:18px;background:#ede5fa;border:1px solid #d9c8ed;margin:18px 0;font-size:14px;line-height:1.6;flex-wrap:wrap}.lesson-direction>span{flex:1;min-width:150px}.lesson-direction .icon{width:24px;height:24px}.lesson-direction button{min-height:44px}.lesson-pointer{position:fixed;z-index:50;pointer-events:none;background:#7551b0;color:white;font-size:14px;font-weight:800;padding:11px 18px;border-radius:16px;box-shadow:0 8px 24px #53357c33;transform:translate(-50%,-100%);max-width:240px;text-align:center}.lesson-pointer:after{content:"";position:absolute;bottom:-9px;left:calc(50% - 8px);border-left:8px solid transparent;border-right:8px solid transparent;border-top:10px solid #7551b0}.lesson-pointer strong{margin-right:6px;font-size:20px}.lesson-task-focus{scroll-margin-block:140px}
@media(max-width:900px){.math-intro{gap:24px}.math-intro h1{font-size:40px}.math-intro .lead{font-size:19px}.math-reading-layout{grid-template-columns:1fr}.math-reading-layout>aside{display:grid;grid-template-columns:1fr 1fr;gap:20px;align-items:start}.math-reading-layout>aside .bio-guide{margin:0}.math-ratio-workspace{grid-template-columns:1fr}.math-playground{padding:24px!important}.math-intro-world>span{font-size:11px;padding:12px;left:10px}}
@media(max-width:600px){.subject-picker{gap:9px;margin-bottom:22px}.subject-picker button{padding:13px 11px;gap:8px;border-radius:18px}.subject-picker strong{font-size:13px}.subject-picker small{font-size:10px}.subject-picker .icon{width:19px;height:19px}.subject-picker button>.icon:last-child{display:none}.math-intro{display:flex;flex-direction:column-reverse;gap:22px;padding:10px 0 24px}.math-intro-world{width:100%;aspect-ratio:1.4}.math-intro-world>img:first-child{border-radius:28px}.math-intro-world>.bio-mira{width:39%;height:91%;right:-4px}.math-intro-world>span{left:13px;bottom:15px;right:38%;font-size:12px}.math-intro h1{font-size:39px;letter-spacing:-1.4px;margin:15px 0}.math-intro p{font-size:15px}.math-goals>span{font-size:13px}.math-time-note{text-align:left;font-size:11px}.math-playground{padding:18px!important}.math-play-top{display:block;margin-bottom:18px;font-size:11px}.math-play-top>span+span{display:block;margin-top:8px}.math-equation{font-size:29px;gap:10px}.math-equation>span{padding:7px 11px}.math-counter-row{flex-wrap:wrap;gap:14px;margin:14px 0}.math-counter-row .math-counter{margin:10px 0;flex:1;min-width:135px}.math-operation{flex-direction:row;justify-content:center;flex-basis:100%;order:3}.math-operation legend{text-align:center}.math-counter button{min-height:46px;width:46px}.math-counter output{font-size:25px;min-width:32px}.math-counter>div{gap:10px}.math-number-line{min-height:125px}.math-presets{gap:8px}.math-presets .quiet{font-size:12px;padding:10px 12px}.math-investigate,.math-worked{padding:22px!important}.math-investigate ol,.math-worked ol{font-size:15px;padding-left:20px}.math-reading-layout>aside{display:block}.math-reading-layout>aside .bio-guide{margin-top:20px}.math-question .bio-choice strong{font-size:15px}.math-question .primary{font-size:13px;padding:14px 18px}.math-fraction-grid{height:96px;gap:3px;padding:5px;border-radius:14px}.math-piece{border-radius:7px;font-size:12px;min-height:44px}.math-fraction-wholes{gap:16px}.math-article{padding:23px!important}.math-article>h2{font-size:26px}.math-article>p{font-size:15px}.math-ice-example>span{padding:17px 5px}.lesson-direction{font-size:13px;padding:14px}.lesson-direction>span{min-width:100px}.lesson-direction>.quiet{margin-left:36px}.math-page .bio-topline{gap:12px;align-items:center}.math-page .bio-topline>span{font-size:10px}.math-page .bio-topline>.quiet{font-size:10px}.math-page .bio-controls .primary{max-width:none}}
@media(prefers-reduced-motion:reduce){.math-page *,.subject-picker *,.math-cover-art{transition:none!important;animation:none!important}.math-piece:hover{transform:none}}