*{box-sizing:border-box}body{margin:0;font-family:Inter,system-ui,sans-serif;background:#f4f7fc;color:#17233d}button,input{font:inherit}button{cursor:pointer}.side{position:fixed;left:0;top:0;bottom:0;width:245px;background:#102b64;color:white;padding:20px 14px;overflow:auto}.logo{width:46px;height:46px;border-radius:14px;background:#795cff;display:grid;place-items:center;font-weight:900;font-size:20px}.side h2{margin:10px 0 0}.side>p{margin:2px 0 18px;color:#a9c0ec;font-size:12px}.side button{width:100%;border:0;background:transparent;color:#d9e5ff;text-align:left;border-radius:10px;padding:10px;margin:2px 0;font-size:12px}.side button span{font-size:18px;margin-right:7px}.side button small{display:block;margin-left:27px;color:#88a6df;font-size:8px}.side button:hover,.side 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#dce4f0;z-index:10;display:flex;flex-direction:column;box-shadow:-10px 0 30px rgba(27,55,95,.08);transition:.2s}.tutor.closed{transform:translateX(100%)}.tutor header{padding:16px;display:flex;align-items:center;gap:9px;border-bottom:1px solid #e4eaf2}.bot{width:38px;height:38px;border-radius:12px;background:linear-gradient(135deg,#7256df,#2b71d7);display:grid;place-items:center}.tutor header b,.tutor header small{display:block}.tutor header small{font-size:9px;color:#718099}.tutor header button{margin-left:auto;border:0;background:#f0f3f8;width:28px;height:28px;border-radius:50%}#chat{flex:1;overflow:auto;padding:14px;background:#f7f9fc}.bubble{padding:10px 12px;border-radius:13px;margin:8px 0;font-size:12px;line-height:1.5;max-width:92%}.bubble.ai{background:white;border:1px solid #dce5f1}.bubble.me{background:#2f64c6;color:white;margin-left:auto}.chips{display:flex;gap:5px;overflow:auto;padding:9px;border-top:1px solid #e4eaf2}.chips button{white-space:nowrap}#tutorForm{display:flex;padding:9px;gap:6px}#tutorInput{min-width:0;flex:1;border:1px solid #cbd8ea;border-radius:11px;padding:10px}#tutorForm button{border:0;background:#3268ca;color:white;border-radius:10px;width:40px}.offline{text-align:center;color:#8a96a9;padding:0 8px 10px;font-size:8px}.tutorFab{display:none;position:fixed;right:15px;bottom:15px;border:0;background:#2e63c6;color:#fff;border-radius:999px;padding:12px 15px;font-weight:900;z-index:9}@media(max-width:1050px){.content{margin-right:0}.tutor{transform:translateX(100%)}.tutor:not(.closed){transform:none}.tutorFab{display:block}}@media(max-width:720px){.side{position:static;width:auto;height:auto;padding:12px;display:flex;align-items:center;gap:8px;overflow:auto}.side .logo{min-width:40px;width:40px;height:40px}.side h2,.side>p{display:none}.side button{white-space:nowrap;width:auto;margin:0;background:#183a78}.side button 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.heroActions{display:flex;gap:10px;flex-wrap:wrap}.reviewCallout{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:18px;margin:20px 0 30px;padding:20px 22px;background:linear-gradient(110deg,#fff9dc,#fff,#eef8ff);border:2px solid #f0d873;border-radius:20px;box-shadow:0 8px 25px rgba(83,69,24,.08)}.reviewCallout .reviewIcon{width:58px;height:58px;display:grid;place-items:center;font-size:32px;border-radius:18px;background:#fff3b8}.reviewCallout small{font-weight:900;letter-spacing:.1em;color:#9a7100}.reviewCallout h2{margin:4px 0 5px;font-size:20px}.reviewCallout p{margin:0;color:#667085;font-size:12px;line-height:1.5}.reviewCallout button{border:0;border-radius:12px;padding:11px 14px;background:#e9a900;color:#fff;font-weight:900}@media(max-width:700px){.reviewCallout{grid-template-columns:auto 1fr}.reviewCallout button{grid-column:1/-1;width:100%}.heroActions{display:grid}.heroActions button{width:100%}}
/* Full-width lesson redesign: no course sidebar */
.side{display:none!important}.topbar{position:sticky;top:0;z-index:20;height:68px;background:rgba(255,255,255,.96);backdrop-filter:blur(14px);border-bottom:1px solid #dce4f0;display:flex;align-items:center;justify-content:space-between;padding:0 max(22px,calc((100vw - 1240px)/2));box-shadow:0 4px 18px rgba(27,55,95,.05)}.brand{border:0;background:transparent;display:flex;align-items:center;gap:9px;color:#17233d}.brand>span{width:40px;height:40px;border-radius:12px;background:linear-gradient(135deg,#2454bb,#7659e5);color:#fff;display:grid;place-items:center;font-weight:950}.brand small{color:#7a879c}.topbar nav{display:flex;gap:6px}.topbar nav button{border:0;background:#f2f5fa;border-radius:10px;padding:9px 12px;color:#315b9f;font-weight:800;font-size:12px}.content{margin:0 auto!important;padding:30px 24px 90px;max-width:1240px}.lesson{max-width:1100px!important}.understand>p,.lead{font-size:16px;line-height:1.75;color:#4d5d75}.whybox{margin-top:18px;padding:17px 18px;border-radius:14px;background:#f0f7ff;border-left:5px solid #3c72d5}.whybox p{margin:5px 0 0;line-height:1.6}.threecol{display:grid;grid-template-columns:1.1fr .9fr 1fr;gap:12px}.threecol .card{margin-top:13px}.vocab{display:grid;gap:3px;padding:10px 0;border-bottom:1px solid #edf1f6}.vocab:last-child{border-bottom:0}.vocab b{color:#2d59a8}.vocab span{font-size:12px;line-height:1.5;color:#66758a}.prerequisite{background:#f8fbff}.rule p{font-size:12px;line-height:1.6;color:#52698e}.steps.deep>div{align-items:start;padding:14px}.steps.deep p{display:grid;gap:5px}.steps.deep p span{font-size:12px;color:#6d7b90;line-height:1.5}.examplesCard>h2{margin-bottom:5px}.deepExample{margin:18px 0}.deepExample header{align-items:center}.deepExample header div{display:grid;gap:3px}.deepExample header small{font-size:8px;letter-spacing:.1em;color:#718099}.workSteps{padding:8px 16px}.workSteps>div{display:grid;grid-template-columns:30px 1fr;gap:10px;padding:12px 0;border-bottom:1px solid #edf1f6}.workSteps>div:last-child{border-bottom:0}.workSteps i{width:27px;height:27px;border-radius:50%;background:#eaf1ff;color:#315fb7;display:grid;place-items:center;font-style:normal;font-weight:900}.workSteps p{margin:0;display:grid;gap:5px;line-height:1.5}.workSteps p span{font-size:11px;color:#728097}.deepExample footer{display:grid;grid-template-columns:auto auto 1fr;align-items:center;gap:8px}.deepExample footer>span{font-size:10px;text-transform:uppercase;letter-spacing:.08em}.deepExample footer>small{margin-left:auto;color:#507461}.correction,.sayit{margin-top:12px;padding:12px;border-radius:11px;background:rgba(255,255,255,.7);font-size:12px;line-height:1.55}.checkpoint{border:2px solid #d6e2f6}.checkpoint>p{line-height:1.65}.reveal{border:0;background:#2f64c6;color:#fff;border-radius:10px;padding:10px 13px;font-weight:800}.revealText{margin-top:12px;padding:14px;border-radius:12px;background:#eef4ff;line-height:1.6;color:#405471}.tutorOverlay{position:fixed;inset:0;background:rgba(12,27,55,.34);z-index:50;display:flex;align-items:flex-end;justify-content:flex-end;padding:18px;transition:.2s}.tutorOverlay.closed{display:none}.tutor{position:relative!important;right:auto!important;top:auto!important;bottom:auto!important;width:min(420px,calc(100vw - 24px))!important;height:min(690px,calc(100vh - 36px));border:1px solid #dce4f0;border-radius:20px;overflow:hidden;transform:none!important;box-shadow:0 24px 70px rgba(15,33,68,.3)}.tutor.closed{transform:none}.tutorFab{display:block!important;position:fixed;right:20px;bottom:20px;border:0;background:linear-gradient(135deg,#2e63c6,#7659e5);color:#fff;border-radius:999px;padding:13px 17px;font-weight:900;z-index:40;box-shadow:0 10px 30px rgba(46,99,198,.3)}
@media(max-width:850px){.threecol{grid-template-columns:1fr}.topbar{padding:0 12px}.topbar nav button:nth-child(2){display:none}.content{padding:18px 13px 82px}.lessonHead{border-radius:18px}.deepExample footer{grid-template-columns:1fr auto}.deepExample footer small{grid-column:1/-1;margin:0}.tutorOverlay{padding:8px}.tutor{height:min(720px,calc(100vh - 16px))}}
@media(max-width:560px){.topbar nav button{padding:8px;font-size:10px}.brand small{display:none}.brand b{font-size:13px}.lessonHead h1{font-size:27px}.card{padding:18px}.understand>p,.lead{font-size:14px}.tutorFab{right:12px;bottom:12px}}
.lessonMenu{background:#fff;border:1px solid #e1e7f0;border-radius:16px;overflow:hidden;margin-bottom:10px}.lessonMenu>button{border:0!important;border-radius:0!important;margin:0!important}.lessonActions{display:flex;gap:7px;padding:8px 12px 12px 58px;border-top:1px solid #edf1f6}.lessonActions button,.lessonLaunch button,.printControls button{border:1px solid #d7e0ee;background:#f7faff;color:#2456a6;border-radius:10px;padding:8px 11px;font-weight:800}.lessonLaunch{display:flex;gap:10px;flex-wrap:wrap;margin-top:18px}.lessonLaunch .primaryLaunch{background:#225fd0;color:white}.workHero{background:linear-gradient(120deg,#173d8f,#5d57d8);color:#fff;padding:27px;border-radius:20px;margin-bottom:14px}.workHero h1{margin:6px 0}.workHero p{margin:0;color:#e4ecff}.practiceTop{display:flex;justify-content:space-between;color:#65738a;font-size:12px;font-weight:900}.bigProblem{text-align:center;background:#f2f6ff;border:1px solid #dbe5f5;border-radius:16px;padding:25px;margin:16px 0;font-size:30px;font-weight:900}.muted{color:#6b778a}.stepWorkspace{display:grid;gap:8px;margin:12px 0 18px}.stepWorkspace label{display:grid;grid-template-columns:70px 1fr;align-items:center;gap:9px}.stepWorkspace span{font-size:11px;font-weight:900;color:#63728a}.stepWorkspace input,.finalAnswer input{width:100%;border:1px solid #cdd9ea;border-radius:10px;padding:11px;background:#fbfdff}.finalAnswer{display:flex;align-items:end;gap:10px}.finalAnswer label{flex:1;font-weight:900;font-size:12px}.finalAnswer button,.helpButtons button,.rightBox button,.quizFinish button{border:0;border-radius:10px;padding:11px 15px;background:#235fcf;color:#fff;font-weight:900}.helpButtons{display:flex;gap:8px;margin-top:12px}.helpButtons button{background:#eef4ff;color:#285db5;border:1px solid #d5e2f6}.hintBox,.wrongBox,.rightBox,.stepHelp{margin-top:14px;padding:14px;border-radius:12px}.hintBox{background:#fff8df;border:1px solid #f1da8e}.wrongBox{background:#fff0f2;border:1px solid #efc4ca}.rightBox{background:#eaf9f1;border:1px solid #b9e7cf}.rightBox button{margin-left:10px}.stepHelp{background:#eef5ff;border:1px solid #cbdcf5}.stepHelp>div{display:flex;gap:10px;margin:8px 0;align-items:center}.stepHelp i{width:28px;height:28px;border-radius:50%;background:#2a61bf;color:#fff;display:grid;place-items:center;font-style:normal}.quizScore{font-size:60px;font-weight:950;color:#245ec7}.quizFinish{text-align:center}.printControls{display:flex;gap:8px;justify-content:flex-end;margin-bottom:12px}.printControls .back{margin-right:auto}.worksheet{background:white;padding:34px;border:1px solid #dfe5ee}.worksheet header{border-bottom:2px solid #222;padding-bottom:12px}.worksheetProblems{display:grid;grid-template-columns:1fr 1fr;gap:24px 35px;margin-top:24px}.worksheetProblems article{break-inside:avoid}.paperLines{height:90px;background:repeating-linear-gradient(to bottom,transparent 0,transparent 28px,#ccd2da 29px,#ccd2da 30px)}.answerKey{margin-top:30px;border-top:2px solid #222;padding-top:14px;display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.answerKey h2{grid-column:1/-1}.answerKey span{font-size:12px}@media(max-width:700px){.lessonActions{padding-left:12px;flex-wrap:wrap}.finalAnswer{display:grid}.worksheetProblems{grid-template-columns:1fr}.printControls{flex-wrap:wrap}.answerKey{grid-template-columns:1fr 1fr}}@media print{body{background:#fff}.topbar,.tutorFab,.tutorOverlay,.printControls{display:none!important}.content{max-width:none!important;padding:0!important}.worksheet{border:0;padding:0}.worksheetProblems{gap:18px 30px}.answerKey{break-before:page}.paperLines{height:75px}}
/* Algebra graphing system */
.graphLesson,.graphPractice{overflow:hidden}.algGraph{display:block;width:min(100%,620px);height:auto;margin:16px auto;background:#fff;border:1px solid #cfd9e8;border-radius:14px;touch-action:manipulation}.algGraph .grid{stroke:#e8edf4;stroke-width:1}.algGraph .axis{stroke:#34445d;stroke-width:2}.algGraph .tick{font-size:9px;fill:#718096;text-anchor:middle}.algGraph .axisLabel{font-size:13px;font-weight:900;fill:#27364d}.algGraph .plotLine{stroke:#2764c7;stroke-width:4}.algGraph .plotLine.second{stroke:#8b55cc}.algGraph .quadLine{fill:none;stroke:#2764c7;stroke-width:4}.algGraph .plotPoint{fill:#f08b32;stroke:white;stroke-width:2}.algGraph .studentPoint{fill:#e45266;stroke:white;stroke-width:2}.algGraph .pointLabel{font-size:10px;font-weight:800;fill:#34445d}.graphNote{font-size:11px;color:#6c7b90}.graphTaskBar{display:flex;justify-content:space-between;gap:12px;align-items:center;font-size:12px;color:#53647d}.graphTaskBar span{font-size:11px}.graphControls{display:flex;align-items:center;gap:12px;justify-content:center}.graphControls button{border:0;border-radius:10px;background:#eef4ff;color:#285db5;padding:9px 13px;font-weight:850}.coordReadout{font-size:12px;color:#5e6f87}.paperGraph .algGraph{width:250px;margin:8px auto;border-radius:0}.paperGraph .plotLine,.paperGraph .quadLine,.paperGraph .plotPoint{display:none}@media(max-width:600px){.graphTaskBar{display:grid}.algGraph{margin:10px auto}.graphControls{flex-wrap:wrap}}@media print{.paperGraph .algGraph{width:220px}.worksheetProblems:has(.paperGraph){grid-template-columns:1fr 1fr}.paperGraph .tick{font-size:8px}}

/* Inline scratch-work drawing pad */
.scratchLaunch{display:flex;align-items:center;justify-content:center;gap:10px;margin:-4px 0 16px}.scratchLaunch small{color:#738096}.scratchBtn{border:1px solid #cddcf3;background:#eef5ff;color:#2459ad;border-radius:11px;padding:10px 14px;font-weight:900}.scratchInline{margin:0 0 20px;border:1px solid #cdd9e9;border-radius:16px;background:#fff;overflow:hidden;box-shadow:0 8px 24px rgba(25,55,95,.08)}.scratchInline header{display:flex;justify-content:space-between;gap:16px;padding:16px 18px 12px;border-bottom:1px solid #e5eaf1}.scratchInline header small{font-size:9px;font-weight:900;letter-spacing:.12em;color:#6b7b91}.scratchInline h2{margin:3px 0;font-size:20px}.scratchInline header p{margin:0;color:#6a778b;font-size:12px}.scratchClose{border:1px solid #d5deeb;background:#f7f9fc;border-radius:9px;padding:8px 12px;height:fit-content;font-weight:800;color:#40516a}.scratchTools{display:flex;align-items:center;gap:7px;flex-wrap:wrap;padding:10px 16px;background:#f7f9fc;border-bottom:1px solid #e5eaf1}.scratchTools button{border:1px solid #d5deeb;background:#fff;color:#38516f;border-radius:9px;padding:8px 10px;font-weight:800}.scratchTools button.active{background:#245fc8;color:#fff;border-color:#245fc8}.scratchTools label{display:flex;align-items:center;gap:6px;font-size:11px;font-weight:800;color:#52637a}.scratchPaper{margin:14px 16px;height:360px;border:1px solid #ccd6e4;border-radius:12px;overflow:hidden;background-color:#fff;background-image:linear-gradient(#e9eef5 1px,transparent 1px),linear-gradient(90deg,#e9eef5 1px,transparent 1px);background-size:28px 28px}.scratchPaper canvas{display:block;width:100%;height:360px;touch-action:none;cursor:crosshair}.scratchInline footer{padding:0 16px 14px;color:#748198;font-size:11px}@media(max-width:600px){.scratchPaper{margin:8px;height:320px}.scratchPaper canvas{height:320px}.scratchLaunch{flex-wrap:wrap}.scratchLaunch small{width:100%;text-align:center}.scratchInline header{padding:12px}.scratchTools{padding:8px}}
@media print{.scratchLaunch,.scratchInline{display:none!important}}
.miniProgress,.unitProgress span{display:block;height:8px;background:#e6edf8;border-radius:999px;overflow:hidden;margin-top:8px}.miniProgress i,.unitProgress span i{display:block;height:100%;background:linear-gradient(90deg,#4f7cff,#7a5cff);border-radius:999px}.unitProgress{margin-top:18px;max-width:460px}.unitProgress b{display:block;margin-bottom:7px}.completeLaunch{background:#eefbf3!important;color:#176b3a!important;border:2px solid #a7e2bd!important}.completeLaunch:disabled{opacity:.75}.lessonMenu button>b{min-width:42px}
/* Gradable graph answers */
.gradableGraph{border:2px solid #b9d2ff;background:#f8fbff}.graphTaskBar{display:flex;justify-content:space-between;gap:12px;align-items:center;flex-wrap:wrap;margin:0 0 10px}.graphTaskBar span{color:#5f6f86;font-size:13px}.graphLineTabs{display:flex;gap:8px;margin:8px 0 10px}.graphLineTabs button{border:1px solid #b9c9df;background:#fff;border-radius:9px;padding:8px 14px;font-weight:900}.graphLineTabs button.active{background:#245fc8;color:#fff;border-color:#245fc8}.studentPoint{fill:#ef476f;stroke:#fff;stroke-width:2}.line1Point{fill:#ef476f}.line2Point{fill:#7a5cff}.studentLine{stroke:#ef476f;stroke-width:4;opacity:.85}.line2Line{stroke:#7a5cff}.studentCurve{fill:none;stroke:#ef476f;stroke-width:4}.graphControls{display:flex;align-items:center;gap:9px;flex-wrap:wrap;margin-top:10px}.graphControls button{border:1px solid #c8d5e8;background:#fff;border-radius:9px;padding:8px 12px;font-weight:800}.coordReadout{font-size:12px;color:#52637a}.graphSubmitNote{display:flex;gap:8px;align-items:center;flex-wrap:wrap;padding:11px 13px;border-radius:10px;background:#eef6ff;color:#24466f;margin:12px 0}.graphSubmitNote span{font-size:12px}.clickGraph svg{touch-action:none;cursor:crosshair}