@font-face{font-display:block;font-family:KaTeX_AMS;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_AMS-Regular-BQhdFMY1.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_AMS-Regular-DMm9YOAa.woff)format("woff"),url(/opengreenbook/assets/KaTeX_AMS-Regular-DRggAlZN.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Caligraphic;font-style:normal;font-weight:700;src:url(/opengreenbook/assets/KaTeX_Caligraphic-Bold-Dq_IR9rO.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Caligraphic-Bold-BEiXGLvX.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Caligraphic-Bold-ATXxdsX0.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Caligraphic;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Caligraphic-Regular-Di6jR-x-.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Caligraphic-Regular-CTRA-rTL.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Caligraphic-Regular-wX97UBjC.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Fraktur;font-style:normal;font-weight:700;src:url(/opengreenbook/assets/KaTeX_Fraktur-Bold-CL6g_b3V.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Fraktur-Bold-BsDP51OF.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Fraktur-Bold-BdnERNNW.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Fraktur;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Fraktur-Regular-CTYiF6lA.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Fraktur-Regular-Dxdc4cR9.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Fraktur-Regular-CB_wures.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:normal;font-weight:700;src:url(/opengreenbook/assets/KaTeX_Main-Bold-Cx986IdX.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Main-Bold-Jm3AIy58.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Main-Bold-waoOVXN0.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:italic;font-weight:700;src:url(/opengreenbook/assets/KaTeX_Main-BoldItalic-DxDJ3AOS.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Main-BoldItalic-SpSLRI95.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Main-BoldItalic-DzxPMmG6.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:italic;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Main-Italic-NWA7e6Wa.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Main-Italic-BMLOBm91.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Main-Italic-3WenGoN9.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Main-Regular-B22Nviop.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Main-Regular-Dr94JaBh.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Main-Regular-ypZvNtVU.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Math;font-style:italic;font-weight:700;src:url(/opengreenbook/assets/KaTeX_Math-BoldItalic-CZnvNsCZ.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Math-BoldItalic-iY-2wyZ7.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Math-BoldItalic-B3XSjfu4.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Math;font-style:italic;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Math-Italic-t53AETM-.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Math-Italic-DA0__PXp.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Math-Italic-flOr_0UB.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:normal;font-weight:700;src:url(/opengreenbook/assets/KaTeX_SansSerif-Bold-D1sUS0GD.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_SansSerif-Bold-DbIhKOiC.woff)format("woff"),url(/opengreenbook/assets/KaTeX_SansSerif-Bold-CFMepnvq.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:italic;font-weight:400;src:url(/opengreenbook/assets/KaTeX_SansSerif-Italic-C3H0VqGB.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_SansSerif-Italic-DN2j7dab.woff)format("woff"),url(/opengreenbook/assets/KaTeX_SansSerif-Italic-YYjJ1zSn.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_SansSerif-Regular-DDBCnlJ7.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_SansSerif-Regular-CS6fqUqJ.woff)format("woff"),url(/opengreenbook/assets/KaTeX_SansSerif-Regular-BNo7hRIc.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Script;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Script-Regular-D3wIWfF6.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Script-Regular-D5yQViql.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Script-Regular-C5JkGWo-.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size1;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Size1-Regular-mCD8mA8B.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Size1-Regular-C195tn64.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Size1-Regular-Dbsnue_I.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size2;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Size2-Regular-Dy4dx90m.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Size2-Regular-oD1tc_U0.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Size2-Regular-B7gKUWhC.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size3;font-style:normal;font-weight:400;src:url(data:font/woff2;base64,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)format("woff2"),url(/opengreenbook/assets/KaTeX_Size3-Regular-CTq5MqoE.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Size3-Regular-DgpXs0kz.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size4;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Size4-Regular-Dl5lxZxV.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Size4-Regular-BF-4gkZK.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Size4-Regular-DWFBv043.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Typewriter;font-style:normal;font-weight:400;src:url(/opengreenbook/assets/KaTeX_Typewriter-Regular-CO6r4hn1.woff2)format("woff2"),url(/opengreenbook/assets/KaTeX_Typewriter-Regular-C0xS9mPB.woff)format("woff"),url(/opengreenbook/assets/KaTeX_Typewriter-Regular-D3Ib7_Hf.ttf)format("truetype")}.katex{text-indent:0;text-rendering:auto;font:1.21em/1.2 KaTeX_Main,Times New Roman,serif;position:relative}.katex *{border-color:currentColor;-ms-high-contrast-adjust:none!important}.katex .katex-version:after{content:"0.18.9"}.katex .katex-mathml{clip-path:inset(50%);border:0;width:1px;height:1px;padding:0;position:absolute;overflow:hidden}.katex .katex-html>.katex-newline{display:block}.katex .katex-base{white-space:nowrap;width:min-content;position:relative}.katex .katex-base,.katex .katex-strut{display:inline-block}.katex .textbf{font-weight:700}.katex .textit{font-style:italic}.katex .textrm{font-family:KaTeX_Main}.katex .textsf{font-family:KaTeX_SansSerif}.katex .texttt{font-family:KaTeX_Typewriter}.katex .mathnormal{font-family:KaTeX_Math;font-style:italic}.katex .mathit{font-family:KaTeX_Main;font-style:italic}.katex .mathrm{font-style:normal}.katex .mathbf{font-family:KaTeX_Main;font-weight:700}.katex .boldsymbol{font-family:KaTeX_Math;font-style:italic;font-weight:700}.katex .amsrm,.katex .mathbb,.katex .textbb{font-family:KaTeX_AMS}.katex .mathcal{font-family:KaTeX_Caligraphic}.katex .mathfrak,.katex .textfrak{font-family:KaTeX_Fraktur}.katex .mathboldfrak,.katex .textboldfrak{font-family:KaTeX_Fraktur;font-weight:700}.katex .mathtt{font-family:KaTeX_Typewriter}.katex .mathscr,.katex .textscr{font-family:KaTeX_Script}.katex .mathsf,.katex .textsf{font-family:KaTeX_SansSerif}.katex .mathboldsf,.katex .textboldsf{font-family:KaTeX_SansSerif;font-weight:700}.katex .mathitsf,.katex .mathsfit,.katex .textitsf{font-family:KaTeX_SansSerif;font-style:italic}.katex .mainrm{font-family:KaTeX_Main;font-style:normal}.katex .vlist-t{border-collapse:collapse;table-layout:fixed;display:inline-table}.katex .vlist-r{display:table-row}.katex .vlist{vertical-align:bottom;display:table-cell;position:relative}.katex .vlist>span{height:0;display:block;position:relative}.katex .vlist>span>span{display:inline-block}.katex .vlist>span>.pstrut{width:0;overflow:hidden}.katex .vlist-t2{margin-right:-2px}.katex .vlist-s{vertical-align:bottom;width:2px;min-width:2px;font-size:1px;display:table-cell}.katex .katex-vbox{flex-direction:column;align-items:baseline;display:inline-flex}.katex .katex-thinbox{flex-direction:row;width:0;max-width:0;display:inline-flex}.katex .msupsub{text-align:left}.katex .mfrac>span>span{text-align:center}.katex .mfrac .frac-line{border-bottom-style:solid;width:100%;display:inline-block}.katex .katex-hdashline,.katex .katex-hline,.katex .katex-overline .overline-line,.katex .katex-rule,.katex .katex-underline .underline-line,.katex .mfrac .frac-line{min-height:1px}.katex .mspace{display:inline-block}.katex .katex-smash{line-height:0;display:inline}.katex .clap,.katex .llap,.katex .rlap{width:0;position:relative}.katex .clap>.katex-inner,.katex .llap>.katex-inner,.katex .rlap>.katex-inner{position:absolute}.katex .clap>.katex-fix,.katex .llap>.katex-fix,.katex .rlap>.katex-fix{display:inline-block}.katex .llap>.katex-inner{right:0}.katex .clap>.katex-inner,.katex .rlap>.katex-inner{left:0}.katex .clap>.katex-inner>span{margin-left:-50%;margin-right:50%}.katex .katex-rule{border:0 solid;display:inline-block;position:relative}.katex .katex-hline,.katex .katex-overline .overline-line,.katex .katex-underline .underline-line{border-bottom-style:solid;width:100%;display:inline-block}.katex .katex-hdashline{border-bottom-style:dashed;width:100%;display:inline-block}.katex .sqrt>.katex-root{margin-left:.277778em;margin-right:-.555556em}.katex .fontsize-ensurer.reset-size1.size1,.katex .katex-sizing.reset-size1.size1{font-size:1em}.katex .fontsize-ensurer.reset-size1.size2,.katex .katex-sizing.reset-size1.size2{font-size:1.2em}.katex .fontsize-ensurer.reset-size1.size3,.katex .katex-sizing.reset-size1.size3{font-size:1.4em}.katex .fontsize-ensurer.reset-size1.size4,.katex .katex-sizing.reset-size1.size4{font-size:1.6em}.katex .fontsize-ensurer.reset-size1.size5,.katex .katex-sizing.reset-size1.size5{font-size:1.8em}.katex .fontsize-ensurer.reset-size1.size6,.katex .katex-sizing.reset-size1.size6{font-size:2em}.katex .fontsize-ensurer.reset-size1.size7,.katex .katex-sizing.reset-size1.size7{font-size:2.4em}.katex .fontsize-ensurer.reset-size1.size8,.katex .katex-sizing.reset-size1.size8{font-size:2.88em}.katex .fontsize-ensurer.reset-size1.size9,.katex .katex-sizing.reset-size1.size9{font-size:3.456em}.katex .fontsize-ensurer.reset-size1.size10,.katex .katex-sizing.reset-size1.size10{font-size:4.148em}.katex .fontsize-ensurer.reset-size1.size11,.katex .katex-sizing.reset-size1.size11{font-size:4.976em}.katex .fontsize-ensurer.reset-size2.size1,.katex .katex-sizing.reset-size2.size1{font-size:.833333em}.katex .fontsize-ensurer.reset-size2.size2,.katex .katex-sizing.reset-size2.size2{font-size:1em}.katex .fontsize-ensurer.reset-size2.size3,.katex .katex-sizing.reset-size2.size3{font-size:1.16667em}.katex .fontsize-ensurer.reset-size2.size4,.katex .katex-sizing.reset-size2.size4{font-size:1.33333em}.katex .fontsize-ensurer.reset-size2.size5,.katex .katex-sizing.reset-size2.size5{font-size:1.5em}.katex .fontsize-ensurer.reset-size2.size6,.katex .katex-sizing.reset-size2.size6{font-size:1.66667em}.katex .fontsize-ensurer.reset-size2.size7,.katex .katex-sizing.reset-size2.size7{font-size:2em}.katex .fontsize-ensurer.reset-size2.size8,.katex .katex-sizing.reset-size2.size8{font-size:2.4em}.katex .fontsize-ensurer.reset-size2.size9,.katex .katex-sizing.reset-size2.size9{font-size:2.88em}.katex .fontsize-ensurer.reset-size2.size10,.katex .katex-sizing.reset-size2.size10{font-size:3.45667em}.katex .fontsize-ensurer.reset-size2.size11,.katex .katex-sizing.reset-size2.size11{font-size:4.14667em}.katex .fontsize-ensurer.reset-size3.size1,.katex .katex-sizing.reset-size3.size1{font-size:.714286em}.katex .fontsize-ensurer.reset-size3.size2,.katex .katex-sizing.reset-size3.size2{font-size:.857143em}.katex .fontsize-ensurer.reset-size3.size3,.katex .katex-sizing.reset-size3.size3{font-size:1em}.katex .fontsize-ensurer.reset-size3.size4,.katex .katex-sizing.reset-size3.size4{font-size:1.14286em}.katex .fontsize-ensurer.reset-size3.size5,.katex .katex-sizing.reset-size3.size5{font-size:1.28571em}.katex .fontsize-ensurer.reset-size3.size6,.katex .katex-sizing.reset-size3.size6{font-size:1.42857em}.katex .fontsize-ensurer.reset-size3.size7,.katex .katex-sizing.reset-size3.size7{font-size:1.71429em}.katex .fontsize-ensurer.reset-size3.size8,.katex .katex-sizing.reset-size3.size8{font-size:2.05714em}.katex .fontsize-ensurer.reset-size3.size9,.katex .katex-sizing.reset-size3.size9{font-size:2.46857em}.katex .fontsize-ensurer.reset-size3.size10,.katex .katex-sizing.reset-size3.size10{font-size:2.96286em}.katex .fontsize-ensurer.reset-size3.size11,.katex .katex-sizing.reset-size3.size11{font-size:3.55429em}.katex .fontsize-ensurer.reset-size4.size1,.katex .katex-sizing.reset-size4.size1{font-size:.625em}.katex .fontsize-ensurer.reset-size4.size2,.katex .katex-sizing.reset-size4.size2{font-size:.75em}.katex .fontsize-ensurer.reset-size4.size3,.katex .katex-sizing.reset-size4.size3{font-size:.875em}.katex .fontsize-ensurer.reset-size4.size4,.katex .katex-sizing.reset-size4.size4{font-size:1em}.katex .fontsize-ensurer.reset-size4.size5,.katex .katex-sizing.reset-size4.size5{font-size:1.125em}.katex .fontsize-ensurer.reset-size4.size6,.katex .katex-sizing.reset-size4.size6{font-size:1.25em}.katex .fontsize-ensurer.reset-size4.size7,.katex .katex-sizing.reset-size4.size7{font-size:1.5em}.katex .fontsize-ensurer.reset-size4.size8,.katex .katex-sizing.reset-size4.size8{font-size:1.8em}.katex .fontsize-ensurer.reset-size4.size9,.katex .katex-sizing.reset-size4.size9{font-size:2.16em}.katex .fontsize-ensurer.reset-size4.size10,.katex .katex-sizing.reset-size4.size10{font-size:2.5925em}.katex .fontsize-ensurer.reset-size4.size11,.katex .katex-sizing.reset-size4.size11{font-size:3.11em}.katex .fontsize-ensurer.reset-size5.size1,.katex .katex-sizing.reset-size5.size1{font-size:.555556em}.katex .fontsize-ensurer.reset-size5.size2,.katex .katex-sizing.reset-size5.size2{font-size:.666667em}.katex .fontsize-ensurer.reset-size5.size3,.katex .katex-sizing.reset-size5.size3{font-size:.777778em}.katex .fontsize-ensurer.reset-size5.size4,.katex .katex-sizing.reset-size5.size4{font-size:.888889em}.katex .fontsize-ensurer.reset-size5.size5,.katex .katex-sizing.reset-size5.size5{font-size:1em}.katex .fontsize-ensurer.reset-size5.size6,.katex .katex-sizing.reset-size5.size6{font-size:1.11111em}.katex .fontsize-ensurer.reset-size5.size7,.katex .katex-sizing.reset-size5.size7{font-size:1.33333em}.katex .fontsize-ensurer.reset-size5.size8,.katex .katex-sizing.reset-size5.size8{font-size:1.6em}.katex .fontsize-ensurer.reset-size5.size9,.katex .katex-sizing.reset-size5.size9{font-size:1.92em}.katex .fontsize-ensurer.reset-size5.size10,.katex .katex-sizing.reset-size5.size10{font-size:2.30444em}.katex .fontsize-ensurer.reset-size5.size11,.katex .katex-sizing.reset-size5.size11{font-size:2.76444em}.katex .fontsize-ensurer.reset-size6.size1,.katex .katex-sizing.reset-size6.size1{font-size:.5em}.katex .fontsize-ensurer.reset-size6.size2,.katex .katex-sizing.reset-size6.size2{font-size:.6em}.katex .fontsize-ensurer.reset-size6.size3,.katex .katex-sizing.reset-size6.size3{font-size:.7em}.katex .fontsize-ensurer.reset-size6.size4,.katex .katex-sizing.reset-size6.size4{font-size:.8em}.katex .fontsize-ensurer.reset-size6.size5,.katex .katex-sizing.reset-size6.size5{font-size:.9em}.katex .fontsize-ensurer.reset-size6.size6,.katex .katex-sizing.reset-size6.size6{font-size:1em}.katex .fontsize-ensurer.reset-size6.size7,.katex .katex-sizing.reset-size6.size7{font-size:1.2em}.katex .fontsize-ensurer.reset-size6.size8,.katex .katex-sizing.reset-size6.size8{font-size:1.44em}.katex .fontsize-ensurer.reset-size6.size9,.katex .katex-sizing.reset-size6.size9{font-size:1.728em}.katex .fontsize-ensurer.reset-size6.size10,.katex .katex-sizing.reset-size6.size10{font-size:2.074em}.katex .fontsize-ensurer.reset-size6.size11,.katex .katex-sizing.reset-size6.size11{font-size:2.488em}.katex .fontsize-ensurer.reset-size7.size1,.katex .katex-sizing.reset-size7.size1{font-size:.416667em}.katex .fontsize-ensurer.reset-size7.size2,.katex .katex-sizing.reset-size7.size2{font-size:.5em}.katex .fontsize-ensurer.reset-size7.size3,.katex .katex-sizing.reset-size7.size3{font-size:.583333em}.katex .fontsize-ensurer.reset-size7.size4,.katex .katex-sizing.reset-size7.size4{font-size:.666667em}.katex .fontsize-ensurer.reset-size7.size5,.katex .katex-sizing.reset-size7.size5{font-size:.75em}.katex .fontsize-ensurer.reset-size7.size6,.katex .katex-sizing.reset-size7.size6{font-size:.833333em}.katex .fontsize-ensurer.reset-size7.size7,.katex .katex-sizing.reset-size7.size7{font-size:1em}.katex .fontsize-ensurer.reset-size7.size8,.katex .katex-sizing.reset-size7.size8{font-size:1.2em}.katex .fontsize-ensurer.reset-size7.size9,.katex .katex-sizing.reset-size7.size9{font-size:1.44em}.katex .fontsize-ensurer.reset-size7.size10,.katex .katex-sizing.reset-size7.size10{font-size:1.72833em}.katex .fontsize-ensurer.reset-size7.size11,.katex .katex-sizing.reset-size7.size11{font-size:2.07333em}.katex .fontsize-ensurer.reset-size8.size1,.katex .katex-sizing.reset-size8.size1{font-size:.347222em}.katex .fontsize-ensurer.reset-size8.size2,.katex .katex-sizing.reset-size8.size2{font-size:.416667em}.katex .fontsize-ensurer.reset-size8.size3,.katex .katex-sizing.reset-size8.size3{font-size:.486111em}.katex .fontsize-ensurer.reset-size8.size4,.katex .katex-sizing.reset-size8.size4{font-size:.555556em}.katex .fontsize-ensurer.reset-size8.size5,.katex .katex-sizing.reset-size8.size5{font-size:.625em}.katex .fontsize-ensurer.reset-size8.size6,.katex .katex-sizing.reset-size8.size6{font-size:.694444em}.katex .fontsize-ensurer.reset-size8.size7,.katex .katex-sizing.reset-size8.size7{font-size:.833333em}.katex .fontsize-ensurer.reset-size8.size8,.katex .katex-sizing.reset-size8.size8{font-size:1em}.katex .fontsize-ensurer.reset-size8.size9,.katex .katex-sizing.reset-size8.size9{font-size:1.2em}.katex .fontsize-ensurer.reset-size8.size10,.katex .katex-sizing.reset-size8.size10{font-size:1.44028em}.katex .fontsize-ensurer.reset-size8.size11,.katex .katex-sizing.reset-size8.size11{font-size:1.72778em}.katex .fontsize-ensurer.reset-size9.size1,.katex .katex-sizing.reset-size9.size1{font-size:.289352em}.katex .fontsize-ensurer.reset-size9.size2,.katex .katex-sizing.reset-size9.size2{font-size:.347222em}.katex .fontsize-ensurer.reset-size9.size3,.katex .katex-sizing.reset-size9.size3{font-size:.405093em}.katex .fontsize-ensurer.reset-size9.size4,.katex .katex-sizing.reset-size9.size4{font-size:.462963em}.katex .fontsize-ensurer.reset-size9.size5,.katex .katex-sizing.reset-size9.size5{font-size:.520833em}.katex .fontsize-ensurer.reset-size9.size6,.katex .katex-sizing.reset-size9.size6{font-size:.578704em}.katex .fontsize-ensurer.reset-size9.size7,.katex .katex-sizing.reset-size9.size7{font-size:.694444em}.katex .fontsize-ensurer.reset-size9.size8,.katex .katex-sizing.reset-size9.size8{font-size:.833333em}.katex .fontsize-ensurer.reset-size9.size9,.katex .katex-sizing.reset-size9.size9{font-size:1em}.katex .fontsize-ensurer.reset-size9.size10,.katex .katex-sizing.reset-size9.size10{font-size:1.20023em}.katex .fontsize-ensurer.reset-size9.size11,.katex .katex-sizing.reset-size9.size11{font-size:1.43981em}.katex .fontsize-ensurer.reset-size10.size1,.katex .katex-sizing.reset-size10.size1{font-size:.24108em}.katex .fontsize-ensurer.reset-size10.size2,.katex .katex-sizing.reset-size10.size2{font-size:.289296em}.katex .fontsize-ensurer.reset-size10.size3,.katex .katex-sizing.reset-size10.size3{font-size:.337512em}.katex .fontsize-ensurer.reset-size10.size4,.katex .katex-sizing.reset-size10.size4{font-size:.385728em}.katex .fontsize-ensurer.reset-size10.size5,.katex .katex-sizing.reset-size10.size5{font-size:.433944em}.katex .fontsize-ensurer.reset-size10.size6,.katex .katex-sizing.reset-size10.size6{font-size:.48216em}.katex .fontsize-ensurer.reset-size10.size7,.katex .katex-sizing.reset-size10.size7{font-size:.578592em}.katex .fontsize-ensurer.reset-size10.size8,.katex .katex-sizing.reset-size10.size8{font-size:.694311em}.katex .fontsize-ensurer.reset-size10.size9,.katex .katex-sizing.reset-size10.size9{font-size:.833173em}.katex .fontsize-ensurer.reset-size10.size10,.katex .katex-sizing.reset-size10.size10{font-size:1em}.katex .fontsize-ensurer.reset-size10.size11,.katex .katex-sizing.reset-size10.size11{font-size:1.19961em}.katex .fontsize-ensurer.reset-size11.size1,.katex .katex-sizing.reset-size11.size1{font-size:.200965em}.katex .fontsize-ensurer.reset-size11.size2,.katex .katex-sizing.reset-size11.size2{font-size:.241158em}.katex .fontsize-ensurer.reset-size11.size3,.katex .katex-sizing.reset-size11.size3{font-size:.281351em}.katex .fontsize-ensurer.reset-size11.size4,.katex .katex-sizing.reset-size11.size4{font-size:.321543em}.katex .fontsize-ensurer.reset-size11.size5,.katex .katex-sizing.reset-size11.size5{font-size:.361736em}.katex .fontsize-ensurer.reset-size11.size6,.katex .katex-sizing.reset-size11.size6{font-size:.401929em}.katex .fontsize-ensurer.reset-size11.size7,.katex .katex-sizing.reset-size11.size7{font-size:.482315em}.katex .fontsize-ensurer.reset-size11.size8,.katex .katex-sizing.reset-size11.size8{font-size:.578778em}.katex .fontsize-ensurer.reset-size11.size9,.katex .katex-sizing.reset-size11.size9{font-size:.694534em}.katex .fontsize-ensurer.reset-size11.size10,.katex .katex-sizing.reset-size11.size10{font-size:.833601em}.katex .fontsize-ensurer.reset-size11.size11,.katex .katex-sizing.reset-size11.size11{font-size:1em}.katex .delimsizing.size1{font-family:KaTeX_Size1}.katex .delimsizing.size2{font-family:KaTeX_Size2}.katex .delimsizing.size3{font-family:KaTeX_Size3}.katex .delimsizing.size4{font-family:KaTeX_Size4}.katex .delimsizing.mult .delim-size1>span{font-family:KaTeX_Size1}.katex .delimsizing.mult .delim-size4>span{font-family:KaTeX_Size4}.katex .nulldelimiter{width:.12em;display:inline-block}.katex .delimcenter,.katex .op-symbol{position:relative}.katex .op-symbol.small-op{font-family:KaTeX_Size1}.katex .op-symbol.large-op{font-family:KaTeX_Size2}.katex .katex-accent>.vlist-t,.katex .op-limits>.vlist-t{text-align:center}.katex .katex-accent .accent-body{position:relative}.katex .katex-accent .accent-body:not(.accent-full){width:0}.katex .katex-overlay{display:block}.katex .mtable .vertical-separator{min-width:1px;display:inline-block}.katex .mtable .arraycolsep{display:inline-block}.katex .mtable .col-align-c>.vlist-t{text-align:center}.katex .mtable .col-align-l>.vlist-t{text-align:left}.katex .mtable .col-align-r>.vlist-t{text-align:right}.katex .svg-align{text-align:left}.katex svg{fill:currentColor;stroke:currentColor;height:inherit;width:100%;display:block;position:absolute}.katex svg path{stroke:none}.katex svg{fill-rule:nonzero;fill-opacity:1;stroke-width:1px;stroke-linecap:butt;stroke-linejoin:miter;stroke-miterlimit:4;stroke-dasharray:none;stroke-dashoffset:0;stroke-opacity:1}.katex img{border-style:none;min-width:0;max-width:none;min-height:0;max-height:none}.katex .katex-stretchy{width:100%;display:block;position:relative;overflow:hidden}.katex .katex-stretchy:after,.katex .katex-stretchy:before{content:""}.katex .hide-tail{width:100%;position:relative;overflow:hidden}.katex .halfarrow-left{width:50.2%;position:absolute;left:0;overflow:hidden}.katex .halfarrow-right{width:50.2%;position:absolute;right:0;overflow:hidden}.katex .brace-left{width:25.1%;position:absolute;left:0;overflow:hidden}.katex .brace-center{width:50%;position:absolute;left:25%;overflow:hidden}.katex .brace-right{width:25.1%;position:absolute;right:0;overflow:hidden}.katex .x-arrow-pad{padding:0 .5em}.katex .cd-arrow-pad{padding:0 .55556em 0 .27778em}.katex .mover,.katex .munder,.katex .x-arrow{text-align:center}.katex .boxpad{padding:0 .3em}.katex .fbox,.katex .fcolorbox{box-sizing:border-box;border:.04em solid}.katex .cancel-pad{padding:0 .2em}.katex .cancel-lap{margin-left:-.2em;margin-right:-.2em}.katex .katex-sout{border-bottom-style:solid;border-bottom-width:.08em}.katex .angl{box-sizing:border-box;border-top:.049em solid;border-right:.049em solid;margin-right:.03889em}.katex .anglpad{padding:0 .03889em}.katex .reflectbox{display:inline-block;transform:scaleX(-1)}.katex .eqn-num:before{content:"(" counter(katexEqnNo) ")";counter-increment:katexEqnNo}.katex .mml-eqn-num:before{content:"(" counter(mmlEqnNo) ")";counter-increment:mmlEqnNo}.katex .mtr-glue{width:50%}.katex .cd-vert-arrow{display:inline-block;position:relative}.katex .cd-label-left{text-align:left;display:inline-block;position:absolute;right:calc(50% + .3em)}.katex .cd-label-right{text-align:right;display:inline-block;position:absolute;left:calc(50% + .3em)}.katex-display{text-align:center;margin:1em 0;display:block}.katex-display>.katex{text-align:center;white-space:nowrap;display:block}.katex-display>.katex>.katex-html{display:block;position:relative}.katex-display>.katex>.katex-html>.katex-tag{position:absolute;right:0}.katex-display.leqno>.katex>.katex-html>.katex-tag{left:0;right:auto}.katex-display.fleqn>.katex{text-align:left;padding-left:2em}body{counter-reset:katexEqnNo mmlEqnNo}:root{--felt-900:#082f16;--felt-800:#0b3d1d;--felt-700:#0f4d24;--felt-600:#15612f;--felt-500:#1c7a3c;--chartreuse:#a8c21a;--chartreuse-soft:#c9dc5a;--ivory:#f4f1e8;--bg:#f4f7f4;--surface:#fff;--surface-2:#edf2ee;--surface-3:#e2e9e4;--text:#1f2d25;--text-2:#4e5f55;--muted:#6d7d73;--border:#d6dfd9;--border-strong:#b7c4bb;--primary:#17693a;--primary-hover:#0f5a2f;--primary-soft:#e3f1e7;--primary-text:#fff;--focus:#a8c21a;--known:#1f9d55;--known-soft:#e2f5ea;--learning:#e07b1a;--learning-soft:#fdf0e3;--wrong:#d64541;--wrong-soft:#fdeceb;--shadow-sm:0 1px 2px #1028180f, 0 1px 3px #10281814;--shadow:0 4px 16px #1028181a;--shadow-lg:0 10px 32px #10281824;--radius:12px;--radius-sm:8px;--font:"Figtree", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;--serif:"EB Garamond", Garamond, "Times New Roman", serif;--mono:"JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light}@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--bg:#07140c;--surface:#10241a;--surface-2:#163024;--surface-3:#1d3b2c;--text:#e8f1ea;--text-2:#bccbc1;--muted:#8fa597;--border:#274634;--border-strong:#3a5f49;--primary:#3fae67;--primary-hover:#52c17a;--primary-soft:#173a26;--primary-text:#04150a;--known:#43c07a;--known-soft:#133823;--learning:#f29b4a;--learning-soft:#3a2614;--wrong:#f06a64;--wrong-soft:#3d1a19;--shadow-sm:0 1px 2px #0006;--shadow:0 4px 18px #00000073;--shadow-lg:0 12px 36px #0000008c;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}}:root[data-theme=dark]{--bg:#07140c;--surface:#10241a;--surface-2:#163024;--surface-3:#1d3b2c;--text:#e8f1ea;--text-2:#bccbc1;--muted:#8fa597;--border:#274634;--border-strong:#3a5f49;--primary:#3fae67;--primary-hover:#52c17a;--primary-soft:#173a26;--primary-text:#04150a;--known:#43c07a;--known-soft:#133823;--learning:#f29b4a;--learning-soft:#3a2614;--wrong:#f06a64;--wrong-soft:#3d1a19;--shadow-sm:0 1px 2px #0006;--shadow:0 4px 18px #00000073;--shadow-lg:0 12px 36px #0000008c;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}*,:before,:after{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{background:var(--bg);color:var(--text);font-family:var(--font);-webkit-font-smoothing:antialiased;margin:0;font-size:16px;line-height:1.5}a{color:var(--primary)}button{font:inherit;color:inherit}h1,h2,h3{margin:0;line-height:1.2}:focus-visible{outline:3px solid var(--focus);outline-offset:2px}.muted{color:var(--muted)}.small{font-size:.85rem}.center{text-align:center}.eyebrow{letter-spacing:.08em;text-transform:uppercase;color:var(--primary);margin:0 0 6px;font-size:.78rem;font-weight:700}.tone-known{color:var(--known);font-weight:700}.tone-learning{color:var(--learning);font-weight:700}.tone-wrong{color:var(--wrong);font-weight:700}.btn{border-radius:var(--radius-sm);cursor:pointer;white-space:nowrap;border:2px solid #0000;justify-content:center;align-items:center;gap:8px;padding:10px 18px;font-size:.95rem;font-weight:700;text-decoration:none;transition:background .15s,border-color .15s,transform .1s,color .15s;display:inline-flex}.btn:active{transform:translateY(1px)}.btn svg{width:20px;height:20px}.btn-lg{padding:13px 22px;font-size:1rem}.btn-sm{padding:6px 12px;font-size:.85rem}.btn-block{width:100%}.btn-primary{background:var(--primary);color:var(--primary-text)}.btn-primary:hover{background:var(--primary-hover)}.btn-ghost{background:var(--surface);border-color:var(--border);color:var(--text)}.btn-ghost:hover{border-color:var(--border-strong);background:var(--surface-2)}.btn-accent{background:var(--chartreuse);color:#0b2a14}.btn-accent:hover{background:var(--chartreuse-soft)}.btn-glass{color:#f4f1e8;background:#ffffff14;border-color:#ffffff40}.btn-glass:hover{background:#ffffff29}.btn-known{background:var(--known);color:#fff}.btn-learning{background:var(--surface);border-color:var(--learning);color:var(--learning)}.link-btn{color:var(--primary);cursor:pointer;background:0 0;border:0;border-radius:6px;align-items:center;gap:6px;padding:6px 8px;font-size:.9rem;font-weight:700;display:inline-flex}.link-btn:hover{background:var(--primary-soft)}.link-btn:disabled{opacity:.4;cursor:default;background:0 0}.link-btn.on{background:var(--primary-soft)}.icon-btn{width:40px;height:40px;color:var(--text-2);cursor:pointer;background:0 0;border:0;border-radius:50%;place-items:center;text-decoration:none;display:inline-grid}.icon-btn:hover,.icon-btn.on{background:var(--surface-2);color:var(--text)}.icon-btn svg{width:22px;height:22px}.circle-btn{border:2px solid var(--border);background:var(--surface);width:52px;height:52px;color:var(--text-2);cursor:pointer;border-radius:50%;place-items:center;transition:border-color .15s,background .15s,color .15s;display:grid}.circle-btn:hover:not(:disabled){border-color:var(--border-strong);background:var(--surface-2);color:var(--text)}.circle-btn:disabled{opacity:.4;cursor:default}.circle-btn.tone-learning-btn{color:var(--learning);border-color:color-mix(in srgb, var(--learning) 45%, var(--border))}.circle-btn.tone-learning-btn:hover{background:var(--learning-soft);border-color:var(--learning);color:var(--learning)}.circle-btn.tone-known-btn{color:var(--known);border-color:color-mix(in srgb, var(--known) 45%, var(--border))}.circle-btn.tone-known-btn:hover{background:var(--known-soft);border-color:var(--known);color:var(--known)}.star-btn{width:36px;height:36px;color:var(--muted);cursor:pointer;background:0 0;border:0;border-radius:50%;flex:none;place-items:center;display:grid}.star-btn:hover{background:var(--surface-2);color:var(--text)}.star-btn.on{color:#e2a50b}.topnav{z-index:20;background:var(--surface);border-bottom:1px solid var(--border);position:sticky;top:0}.topnav-inner{align-items:center;gap:20px;max-width:1200px;height:64px;margin:0 auto;padding:0 16px;display:flex}.brand{color:var(--text);flex:none;align-items:center;gap:10px;text-decoration:none;display:flex}.brand-die{width:32px;height:32px}.brand-die .die-face{fill:var(--felt-700)}.brand-die .die-pip{fill:var(--chartreuse)}.brand-word{letter-spacing:-.02em;font-size:1.2rem;font-weight:800}.brand-word span{color:var(--primary)}.search{background:var(--surface-2);max-width:560px;height:42px;color:var(--muted);border:2px solid #0000;border-radius:999px;flex:1;align-items:center;gap:10px;padding:0 16px;transition:border-color .15s,background .15s;display:flex}.search:focus-within{border-color:var(--primary);background:var(--surface)}.search input{min-width:0;font:inherit;color:var(--text);background:0 0;border:0;outline:0;flex:1}.search input::placeholder{color:var(--muted)}.topnav-actions{gap:4px;margin-left:auto;display:flex}main{min-height:calc(100vh - 184px)}.footer{max-width:900px;color:var(--muted);text-align:center;border-top:1px solid var(--border);margin:64px auto 0;padding:24px 16px 40px;font-size:.85rem}.topnav-links{flex:none;gap:4px;display:flex}.topnav-links a{border-radius:var(--radius-sm);color:var(--text-2);padding:8px 12px;font-size:.95rem;font-weight:700;text-decoration:none}.topnav-links a:hover{background:var(--surface-2);color:var(--text)}.topnav-links a.active{color:var(--primary);background:var(--primary-soft)}.streak{color:var(--learning);background:var(--learning-soft);border-radius:999px;align-self:center;align-items:center;gap:4px;height:30px;padding:0 10px;font-size:.9rem;font-weight:800;display:inline-flex}.nav-die,.btn-die{width:22px;height:22px}.nav-die .die-face{fill:none;stroke:currentColor;stroke-width:2px}.nav-die .die-pip{fill:currentColor}.btn-die .die-face{fill:var(--ivory)}.btn-die .die-pip{fill:var(--felt-700)}.show-sm{display:none}.icon-btn.sm{width:32px;height:32px}.rot{transform:rotate(180deg)}.page{max-width:960px;margin:0 auto;padding:28px 16px 0}.page.narrow{max-width:760px}.page-title{letter-spacing:-.02em;margin-bottom:6px;font-size:clamp(1.7rem,3.5vw,2.2rem);font-weight:800}.lead{margin:0 0 22px;font-size:1.05rem}.back-link{color:var(--text-2);align-items:center;gap:6px;margin-bottom:18px;font-size:.9rem;font-weight:700;text-decoration:none;display:inline-flex}.back-link:hover{color:var(--primary)}.section-head{flex-wrap:wrap;justify-content:space-between;align-items:baseline;gap:12px;margin-bottom:14px;display:flex}.section-head h2{font-size:1.25rem;font-weight:800}.panel{background:var(--surface);border-radius:var(--radius);box-shadow:var(--shadow-sm);margin-bottom:16px;padding:22px 24px}.panel.center{text-align:center}.panel h2{margin-bottom:10px;font-size:1.1rem;font-weight:800}.panel-head{justify-content:space-between;align-items:center;gap:12px;display:flex}.panel-tools{gap:4px;display:flex}.status-icon{border:2px solid var(--border-strong);color:#fff;background:0 0;border-radius:50%;flex:none;place-items:center;display:inline-grid}.status-icon.st-tried{border-color:var(--learning);background:var(--learning);box-shadow:inset 0 0 0 3px var(--surface)}.status-icon.st-solved{border-color:var(--known);color:var(--known)}.status-icon.st-solved.first{background:var(--known);color:#fff}.status-icon.st-revealed{border-color:var(--muted);background:var(--muted);color:var(--surface)}.type-tag{letter-spacing:.02em;white-space:nowrap;color:var(--text-2);background:var(--surface-2);border-radius:999px;flex:none;padding:2px 8px;font-size:.72rem;font-weight:700;display:inline-block}.tt-number{color:var(--primary);background:var(--primary-soft)}.tt-text{color:color-mix(in srgb, var(--chartreuse) 55%, var(--text));background:color-mix(in srgb, var(--chartreuse) 18%, var(--surface))}.tt-concept{border:1px solid var(--border);color:var(--muted);background:0 0}.pbar{background:var(--surface-3);border-radius:999px;height:8px;display:flex;overflow:hidden}.pbar.thin{height:5px}.pb-solved{background:var(--known)}.pb-tried{background:var(--learning)}.pb-revealed{background:var(--muted)}.chips{flex-wrap:wrap;gap:8px;display:flex}.chip{border:2px solid var(--border);background:var(--surface);color:var(--text-2);cursor:pointer;border-radius:999px;flex:none;padding:7px 14px;font-size:.85rem;font-weight:600}.chip b{color:var(--primary);margin-right:2px}.chip:hover{border-color:var(--border-strong)}.chip.on{border-color:var(--primary);background:var(--primary-soft);color:var(--text)}.toggle{cursor:pointer;color:var(--text-2);-webkit-user-select:none;user-select:none;align-items:center;gap:10px;font-size:.9rem;font-weight:600;display:inline-flex}.toggle input{opacity:0;width:1px;height:1px;position:absolute}.toggle-track{background:var(--border-strong);border-radius:999px;flex:none;width:40px;height:24px;transition:background .15s;position:relative}.toggle-thumb{background:#fff;border-radius:50%;width:18px;height:18px;transition:transform .15s;position:absolute;top:3px;left:3px;box-shadow:0 1px 3px #0000004d}.toggle input:checked+.toggle-track{background:var(--primary)}.toggle input:checked+.toggle-track .toggle-thumb{transform:translate(16px)}.toggle input:focus-visible+.toggle-track{outline:3px solid var(--focus);outline-offset:2px}.rich p{margin:0 0 .6em}.rich p:last-child{margin-bottom:0}.rich ul{margin:.2em 0 .7em;padding-left:1.3em}.rich li{margin:.2em 0}.rich code{font-family:var(--mono);background:var(--surface-2);border-radius:4px;padding:1px 5px;font-size:.88em}.rich pre{background:var(--surface-2);border-radius:var(--radius-sm);margin:.4em 0 .8em;padding:12px 14px;font-size:.85rem;line-height:1.45;overflow-x:auto}.rich pre code{font-size:inherit;background:0 0;padding:0}.rich-display{margin:.2em 0 .7em;padding:2px 0;overflow:auto hidden}.katex{font-size:1.06em}.home{max-width:1200px;margin:0 auto;padding:24px 16px 0}.hero{color:var(--ivory);background:var(--felt-700);box-shadow:var(--shadow-lg);border-radius:20px;grid-template-columns:minmax(0,1.4fr) minmax(0,1fr);gap:24px;padding:44px 48px 38px;display:grid;position:relative;overflow:hidden}.hero-book{font-family:var(--serif);color:var(--chartreuse);margin:0 0 14px;font-size:1.25rem;font-weight:600}.hero h1{letter-spacing:-.03em;color:#fff;font-size:clamp(2rem,4.2vw,3.1rem);font-weight:800}.hero-sub{color:#f4f1e8d9;max-width:560px;margin:16px 0 26px;font-size:1.05rem}.hero-cta{flex-wrap:wrap;gap:12px;display:flex}.hero-stats{flex-wrap:wrap;gap:36px;margin:30px 0 0;display:flex}.hero-stats dt{letter-spacing:.08em;text-transform:uppercase;color:#f4f1e8a6;font-size:.75rem;font-weight:700}.hero-stats dd{color:var(--chartreuse);margin:2px 0 0;font-size:1.7rem;font-weight:800}.hero-stats dd small{color:#f4f1e899;font-size:.95rem;font-weight:700}.hero-dice{min-height:260px;position:relative}.hd{filter:drop-shadow(10px 14px 10px #00000073);width:84px;height:84px;position:absolute}.hd .die-face{fill:#eeeae3}.hd .die-pip{fill:#151515}.hd1{top:4%;left:6%;transform:rotate(-8deg)}.hd2{top:22%;left:38%;transform:rotate(6deg)}.hd3{top:14%;right:4%;transform:rotate(-4deg)}.hd4{bottom:4%;left:10%;transform:rotate(3deg)}.hd5{bottom:0;left:54%;transform:rotate(-10deg)}.continue{background:var(--surface);border-radius:var(--radius);box-shadow:var(--shadow-sm);color:var(--text);border-left:5px solid var(--chartreuse);align-items:center;gap:14px;margin-top:16px;padding:16px 20px;text-decoration:none;display:flex}.continue:hover{box-shadow:var(--shadow)}.continue-label{letter-spacing:.08em;text-transform:uppercase;color:var(--primary);font-size:.75rem;font-weight:800}.continue-num{font-family:var(--mono);color:var(--muted);font-size:.9rem}.continue-name{text-overflow:ellipsis;white-space:nowrap;flex:1;min-width:0;font-weight:800;overflow:hidden}.continue-arrow{color:var(--primary);flex:none}.home-section{margin-top:36px}.toc-grid{grid-template-columns:repeat(auto-fill,minmax(340px,1fr));align-items:start;gap:16px;display:grid}.toc-card{background:var(--surface);border-radius:var(--radius);box-shadow:var(--shadow-sm);overflow:hidden}.toc-head{color:var(--text);border-bottom:1px solid var(--border);padding:18px 20px 14px;text-decoration:none;display:block}.toc-head:hover{background:var(--surface-2)}.toc-head h3{margin-bottom:10px;font-size:1.15rem;font-weight:800}.toc-meta{grid-template-columns:1fr auto;align-items:center;gap:12px;display:grid}.toc-sections{margin:0;padding:6px 8px 10px;list-style:none}.toc-sections a{border-radius:var(--radius-sm);color:var(--text-2);grid-template-columns:34px 1fr auto;align-items:baseline;gap:8px;padding:7px 12px;font-size:.93rem;text-decoration:none;display:grid}.toc-sections a:hover{background:var(--primary-soft);color:var(--text)}.toc-sid{color:var(--primary);font-size:.85rem;font-weight:800}.toc-count{color:var(--muted);font-variant-numeric:tabular-nums;font-size:.8rem;font-weight:700}.toc-count.done{color:var(--known)}.chapter-head{flex-wrap:wrap;justify-content:space-between;align-items:flex-end;gap:20px;margin-bottom:18px;display:flex}.chapter-head .muted{margin:0}.chapter-actions{flex-wrap:wrap;gap:10px;display:flex}.chapter-progress{margin-bottom:18px}.legend{color:var(--text-2);flex-wrap:wrap;gap:8px 18px;margin-top:10px;font-size:.85rem;display:flex}.legend span{align-items:center;gap:6px;display:inline-flex}.chapter-progress+.chips{margin-bottom:20px}.sec-block{background:var(--surface);border-radius:var(--radius);box-shadow:var(--shadow-sm);margin-bottom:16px;padding:18px 12px 10px;scroll-margin-top:80px}.sec-block.focus{box-shadow:0 0 0 3px var(--chartreuse), var(--shadow-sm)}.sec-block>.pbar{margin:0 12px 8px}.sec-head{align-items:center;gap:12px;padding:0 12px 10px;display:flex}.sec-head h2{flex:1;font-size:1.08rem;font-weight:800}.sec-head h2 span{color:var(--primary);margin-right:4px}.sec-count{color:var(--muted);font-variant-numeric:tabular-nums;font-size:.9rem;font-weight:800}.prob-list{margin:0;padding:0;list-style:none}.prob-row{border-radius:var(--radius-sm);grid-template-columns:minmax(0,1fr) auto;align-items:center;display:grid}.prob-row:hover{background:var(--surface-2)}.pr-link{color:var(--text);grid-template-columns:auto 48px minmax(0,1fr) auto 44px;align-items:center;gap:12px;min-width:0;padding:10px 12px;text-decoration:none;display:grid}.pr-num{font-family:var(--mono);color:var(--muted);font-size:.82rem}.pr-name{text-overflow:ellipsis;white-space:nowrap;align-items:center;gap:8px;min-width:0;font-weight:600;display:flex;overflow:hidden}.pr-page{text-align:right}.empty-note{margin:0;padding:4px 12px 10px}.res-tag{background:var(--surface-2);color:var(--muted);border-radius:999px;padding:2px 8px;font-size:.75rem;font-weight:800}.res-first{background:var(--known-soft);color:var(--known)}.res-retry{background:color-mix(in srgb, var(--known) 10%, var(--surface));color:var(--known)}.res-revealed{background:var(--surface-3);color:var(--text-2)}main.wide{min-height:calc(100vh - 64px)}.trainer{grid-template-columns:300px minmax(0,1fr);min-height:calc(100vh - 64px);display:grid}.trainer-side{background:var(--surface);border-right:1px solid var(--border);overscroll-behavior:contain;height:calc(100vh - 64px);position:sticky;top:64px;overflow-y:auto}.trainer-main{width:100%;max-width:860px;margin:0 auto;padding:20px 24px 60px}.crumbs-row{align-items:center;gap:12px;margin-bottom:14px;display:flex}.drawer-btn{display:none}.crumbs{min-width:0;color:var(--muted);flex-wrap:wrap;flex:1;align-items:center;gap:8px;font-size:.9rem;font-weight:600;display:flex}.crumbs a{color:var(--text-2);text-decoration:none}.crumbs a:hover{color:var(--primary);text-decoration:underline}.pager{flex:none;align-items:center;gap:8px;display:flex}.circle-btn.sm{border-width:2px;width:38px;height:38px}a.circle-btn{text-decoration:none}a.circle-btn.disabled{opacity:.35;pointer-events:none}.sidebar{padding:16px 12px 40px}.sb-chapter{border-bottom:1px solid var(--border);margin-bottom:8px;padding:0 6px 12px}.sb-label{letter-spacing:.08em;text-transform:uppercase;color:var(--muted);margin-bottom:6px;font-size:.72rem;font-weight:800;display:block}.sb-chapter select{border-radius:var(--radius-sm);border:2px solid var(--border);background:var(--surface-2);width:100%;color:var(--text);font:inherit;cursor:pointer;padding:9px 10px;font-size:.92rem;font-weight:700}.sb-sections,.sb-problems{margin:0;padding:0;list-style:none}.sb-section-btn{border-radius:var(--radius-sm);text-align:left;cursor:pointer;background:0 0;border:0;grid-template-columns:30px 1fr auto;align-items:baseline;gap:6px;width:100%;padding:9px 8px;display:grid}.sb-section-btn:hover{background:var(--surface-2)}.sb-sid{color:var(--primary);font-size:.82rem;font-weight:800}.sb-stitle{font-size:.9rem;font-weight:700;line-height:1.3}.sb-count{color:var(--muted);font-variant-numeric:tabular-nums;font-size:.75rem;font-weight:700}.sb-problems{padding:2px 0 8px 10px}.sb-problem{color:var(--text-2);border-left:3px solid #0000;border-radius:6px;grid-template-columns:auto 20px 1fr;align-items:center;gap:8px;padding:6px 8px;font-size:.87rem;text-decoration:none;display:grid}.sb-problem:hover{background:var(--surface-2);color:var(--text)}.sb-problem.current{background:var(--primary-soft);border-left-color:var(--primary);color:var(--text);font-weight:700}.sb-pnum{font-family:var(--mono);color:var(--muted);text-align:right;font-size:.75rem}.sb-pname{text-overflow:ellipsis;white-space:nowrap;overflow:hidden}.scrim{display:none}.problem{background:var(--surface);border-radius:var(--radius);box-shadow:var(--shadow);padding:28px 32px 26px}.problem-head{align-items:center;gap:12px;display:flex}.pnum{font-family:var(--mono);background:var(--felt-700);color:var(--chartreuse);border-radius:6px;flex:none;padding:3px 9px;font-size:.88rem;font-weight:500}.pname{letter-spacing:-.01em;flex:1;min-width:0;font-size:1.4rem;font-weight:800}.problem-meta{flex-wrap:wrap;align-items:center;gap:8px 12px;margin:10px 0 18px;display:flex}.prior{color:var(--text-2);align-items:center;gap:6px;font-size:.8rem;font-weight:700;display:inline-flex}.problem-prompt{margin-bottom:18px;font-size:1.2rem;line-height:1.6}.hint-row{margin:-6px 0 14px}.hint-text{border-radius:var(--radius-sm);background:color-mix(in srgb, var(--chartreuse) 14%, var(--surface));color:var(--text-2);align-items:flex-start;gap:8px;margin:0;padding:10px 14px;font-size:.95rem;display:flex}.hint-text svg{color:color-mix(in srgb, var(--chartreuse) 60%, var(--text));flex:none;margin-top:2px}.answer-form{margin-top:4px}.answer-label{letter-spacing:.08em;text-transform:uppercase;color:var(--muted);margin-bottom:8px;font-size:.75rem;font-weight:800;display:block}.answer-row{align-items:stretch;gap:12px;display:flex}.answer-box{border:2px solid var(--border-strong);background:var(--surface);border-radius:10px;flex:1;align-items:center;gap:8px;min-width:0;min-height:56px;padding:0 16px;transition:border-color .15s,background .15s,box-shadow .15s;display:flex}.answer-box:focus-within{border-color:var(--primary);box-shadow:0 0 0 4px var(--primary-soft)}.answer-box input{min-width:0;font:inherit;color:var(--text);background:0 0;border:0;outline:0;flex:1;font-size:1.25rem;font-weight:600}.answer-box input::placeholder{color:var(--muted);font-size:1rem;font-weight:400}.answer-unit{color:var(--muted);flex:none;font-weight:700}.answer-box.bad{border-color:var(--wrong);background:var(--wrong-soft)}.answer-box.ok{border-color:var(--known);background:var(--known-soft)}.answer-ok{color:var(--known);flex:none}.answer-box.shake{animation:.32s shake}@keyframes shake{20%{transform:translate(-6px)}40%{transform:translate(6px)}60%{transform:translate(-4px)}80%{transform:translate(4px)}}.answer-help{color:var(--muted);margin:8px 2px 0;font-size:.85rem}.answer-help.live{color:var(--primary)}.feedback-msg{border-radius:var(--radius-sm);flex-wrap:wrap;align-items:center;gap:8px 10px;margin-top:14px;padding:10px 14px;font-weight:700;display:flex}.fb-wrong{background:var(--wrong-soft);color:var(--wrong)}.fb-invalid{background:var(--learning-soft);color:color-mix(in srgb, var(--learning) 70%, var(--text))}.feedback-msg .link-btn{margin-left:auto}.problem-actions{border-top:1px solid var(--border);justify-content:space-between;align-items:center;margin-top:18px;padding-top:14px;display:flex}.muted-link{color:var(--muted)}.choices{grid-template-columns:1fr 1fr;gap:12px;display:grid}.choice{text-align:left;background:var(--surface);border:2px solid var(--border);border-radius:var(--radius-sm);cursor:pointer;overflow-wrap:anywhere;align-items:center;gap:12px;min-width:0;min-height:60px;padding:12px 16px;font-weight:600;transition:border-color .15s,background .15s,opacity .15s;display:flex}.choice:hover:not(:disabled){border-color:var(--primary);background:var(--primary-soft)}.choice:disabled{cursor:default}.choice-key{background:var(--surface-2);width:28px;height:28px;color:var(--text-2);border-radius:50%;flex:none;place-items:center;font-size:.8rem;font-weight:800;display:grid}.choice.right{border-color:var(--known);background:var(--known-soft)}.choice.right .choice-key{background:var(--known);color:#fff}.choice.wrong{border-color:var(--wrong);background:var(--wrong-soft);border-style:dashed}.choice.wrong .choice-key{background:var(--wrong);color:#fff}.choice.dim{opacity:.55}.solution{margin-top:20px}.result-banner{border-radius:var(--radius-sm);align-items:center;gap:14px;padding:14px 16px;display:flex}.result-banner div{flex-direction:column;display:flex}.result-banner strong{font-size:1.1rem}.result-banner span{color:var(--text-2);font-size:.9rem}.result-banner.ok{background:var(--known-soft)}.result-banner.ok strong{color:var(--known)}.result-banner.shown{background:var(--surface-2)}.rb-icon{background:var(--known);border-radius:50%;flex:none;place-items:center;width:40px;height:40px;display:grid;color:#fff!important}.result-banner.shown .rb-icon{background:var(--muted)}.solution-body{padding:18px 4px 4px}.sol-label{letter-spacing:.08em;text-transform:uppercase;color:var(--muted);margin:0 0 6px;font-size:.72rem;font-weight:800}.sol-answer{border-left:4px solid var(--chartreuse);margin-bottom:18px;padding-left:12px;font-size:1.2rem;font-weight:700}.sol-explain{color:var(--text-2);line-height:1.65}.next-row{border-top:1px solid var(--border);justify-content:flex-end;align-items:center;gap:14px;margin-top:20px;padding-top:16px;display:flex}.topic-tree{margin:8px 0 0;padding:0;list-style:none}.topic-tree>li{border-top:1px solid var(--border)}.topic-row{align-items:center;gap:10px;padding:8px 0;display:flex}.check{cursor:pointer;flex:1;align-items:center;gap:10px;font-weight:600;display:flex}.check input{width:18px;height:18px;accent-color:var(--primary)}.check b{color:var(--primary)}.topic-sections{flex-wrap:wrap;gap:8px;padding:2px 0 14px 28px;display:flex}.opt-row{border-top:1px solid var(--border);flex-wrap:wrap;justify-content:space-between;align-items:center;gap:16px;padding:12px 0;font-weight:600;display:flex}.panel h2+.opt-row{border-top:0}.segmented{background:var(--surface-2);border-radius:999px;padding:3px;display:inline-flex}.segmented button{color:var(--text-2);cursor:pointer;background:0 0;border:0;border-radius:999px;padding:6px 14px;font-size:.88rem;font-weight:700}.segmented button.on{background:var(--surface);color:var(--primary);box-shadow:var(--shadow-sm)}.start-bar{background:var(--surface);border-radius:var(--radius);box-shadow:var(--shadow-lg);justify-content:space-between;align-items:center;gap:12px;padding:14px 18px;display:flex;position:sticky;bottom:16px}.btn:disabled{opacity:.5;cursor:not-allowed}.session-bar{margin-bottom:16px}.sb-top{align-items:center;gap:14px;margin-bottom:8px;display:flex}.session-title{color:var(--primary);align-items:center;gap:6px;font-weight:800;display:inline-flex}.session-pos{color:var(--text-2);flex:1;font-weight:700}.session-score{background:var(--known-soft);color:var(--known);border-radius:999px;align-items:center;gap:4px;padding:2px 10px;font-weight:800;display:inline-flex}.session-track{background:var(--surface-3);border-radius:999px;height:6px;overflow:hidden}.session-track span{background:var(--primary);height:100%;transition:width .3s;display:block}.session-crumb{margin:0 0 10px}.session-crumb a{color:var(--muted);font-weight:700;text-decoration:none}.score-big{align-items:center;gap:22px;margin-bottom:18px;display:flex}.score-num{letter-spacing:-.03em;color:var(--primary);font-size:3.2rem;font-weight:800;line-height:1}.score-num small{color:var(--muted);font-size:1.4rem}.score-big h2{margin-bottom:4px;font-size:1.4rem}.score-big p{margin:0}.results .prob-list{margin:0 -12px 18px}.results .pr-link{grid-template-columns:auto 48px minmax(0,1fr) auto}.summary-actions{flex-wrap:wrap;gap:12px;display:flex}.search-list{gap:10px;margin:18px 0 0;padding:0;list-style:none;display:grid}.search-row{background:var(--surface);border-radius:var(--radius-sm);box-shadow:var(--shadow-sm);color:var(--text);padding:14px 18px;text-decoration:none;display:block}.search-row:hover{box-shadow:var(--shadow)}.sr-top{align-items:center;gap:10px;margin-bottom:6px;display:flex}.sr-top .pr-name{flex:1}.sr-prompt{color:var(--text-2);-webkit-line-clamp:2;-webkit-box-orient:vertical;font-size:.92rem;display:-webkit-box;overflow:hidden}@media (width<=1000px){.trainer{grid-template-columns:1fr}.trainer-side{z-index:50;width:min(320px,86vw);height:100vh;box-shadow:var(--shadow-lg);transition:transform .22s;position:fixed;top:0;bottom:0;left:0;transform:translate(-100%)}.trainer-side.open{transform:none}.scrim{z-index:45;background:#0006;display:block;position:fixed;inset:0}.drawer-btn{flex:none;display:inline-flex}}@media (width<=860px){.hero{grid-template-columns:1fr;padding:32px 24px}.hero-dice{display:none}}@media (width<=720px){.topnav-links,.hide-sm{display:none}.show-sm{display:inline-grid}.brand-word{display:none}.topnav-inner{gap:10px}.search{height:40px;padding:0 12px}.streak{display:none}}@media (width<=640px){.hero{border-radius:16px;padding:28px 20px}.hero-stats{gap:22px}.toc-grid{grid-template-columns:1fr}.trainer-main{padding:14px 12px 40px}.crumbs{display:none}.crumbs-row{justify-content:space-between}.problem{padding:20px 18px}.pname{font-size:1.2rem}.problem-prompt{font-size:1.08rem}.answer-row{flex-direction:column}.choices{grid-template-columns:1fr}.pr-link{grid-template-columns:auto 44px minmax(0,1fr);gap:10px}.pr-link .type-tag,.pr-page{display:none}.results .pr-link{grid-template-columns:auto 44px minmax(0,1fr) auto}.chapter-actions,.chapter-actions .btn{width:100%}.sec-head .btn{display:none}.panel{padding:18px}.start-bar{text-align:center;flex-direction:column;align-items:stretch}.score-big{flex-direction:column;align-items:flex-start}.summary-actions .btn{width:100%}.next-row .kbd-hint{display:none}.next-row .btn{width:100%}}@media (prefers-reduced-motion:reduce){*,:before,:after{transition-duration:.01ms!important;animation-duration:.01ms!important}}