.physics-kicker.physics-kicker{z-index:12;letter-spacing:0;text-transform:none;white-space:nowrap;color:#b0bcc1;align-items:center;gap:20px;min-height:46px;margin:0;font-family:PingFang SC,Microsoft YaHei,sans-serif;font-size:35px;font-weight:400;line-height:1.3;display:flex;position:relative}.physics-kicker.physics-kicker>svg{color:#d8ff63;stroke-width:1.8px;flex:none;width:36px;height:36px}.physics-kicker.physics-kicker>.physics-chapter{color:#d8ff63;letter-spacing:0;flex:none;font:400 35px/1.3 monospace}.physics-kicker.physics-kicker>i{background:#ffffff40;flex:none;width:1px;height:28px;margin:0;display:block}.physics-kicker.physics-kicker>.physics-topic{font:inherit;color:#b0bcc1;letter-spacing:0;margin:0;padding:0}.physics-nav.physics-nav{z-index:40;box-sizing:border-box;-webkit-backdrop-filter:blur(18px);opacity:0;visibility:hidden;pointer-events:none;transform-origin:bottom;color:#f4f2ea;background:#11191bea;border:1px solid #ffffff25;border-radius:15px;align-items:center;gap:14px;width:1040px;max-width:none;height:72px;margin:0;padding:10px 16px;font-family:PingFang SC,Microsoft YaHei,sans-serif;transition:opacity .2s,visibility .2s;display:flex;position:fixed;bottom:16px;left:50%;box-shadow:0 10px 40px #0008}.physics-nav.physics-nav.is-visible,.physics-nav.physics-nav:focus-within,.physics-nav.physics-nav:hover{opacity:1;visibility:visible;pointer-events:auto}.physics-nav.physics-nav button{width:48px;min-width:0;height:48px;box-shadow:none;color:#f4f2ea;cursor:pointer;background:0 0;border:0;border-radius:7px;flex:none;justify-content:center;align-items:center;margin:0;padding:0;font:35px/1 sans-serif;display:flex;position:relative}.physics-nav.physics-nav button:hover{background:#ffffff0c}.physics-nav.physics-nav button:disabled{opacity:.25;cursor:default}.physics-nav.physics-nav button:focus-visible{outline-offset:2px;outline:2px solid #75e6ff}.physics-nav.physics-nav svg{pointer-events:none;width:35px;height:35px}.physics-page-count{text-align:center;white-space:nowrap;flex:none;min-width:128px;font:35px/1.3 monospace}.physics-page-segments{flex:1;align-items:center;gap:8px;min-width:0;display:flex}.physics-nav.physics-nav .physics-page-segments button{border-radius:4px;flex:1;width:auto;min-width:8px;height:46px}.physics-page-segments button>span{pointer-events:none;background:#ffffff30;border-radius:5px;width:100%;height:7px}.physics-page-segments button[aria-current=page]>span{background:#d8ff63;box-shadow:0 0 12px #d8ff6340}.physics-extra-actions{flex:none;gap:4px;display:flex}.physics-nav.physics-nav .physics-fullscreen{border-left:1px solid #ffffff30;border-radius:0;width:62px;padding-left:14px}.physics-page-picker{display:none}@font-face{font-display:block;font-family:KaTeX_AMS;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_AMS-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_AMS-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_AMS-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Caligraphic;font-style:normal;font-weight:700;src:url(/lessons/25/katex/fonts/KaTeX_Caligraphic-Bold.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Caligraphic-Bold.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Caligraphic-Bold.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Caligraphic;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Caligraphic-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Caligraphic-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Caligraphic-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Fraktur;font-style:normal;font-weight:700;src:url(/lessons/25/katex/fonts/KaTeX_Fraktur-Bold.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Fraktur-Bold.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Fraktur-Bold.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Fraktur;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Fraktur-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Fraktur-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Fraktur-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:normal;font-weight:700;src:url(/lessons/25/katex/fonts/KaTeX_Main-Bold.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Main-Bold.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Main-Bold.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:italic;font-weight:700;src:url(/lessons/25/katex/fonts/KaTeX_Main-BoldItalic.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Main-BoldItalic.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Main-BoldItalic.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:italic;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Main-Italic.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Main-Italic.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Main-Italic.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Main-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Main-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Main-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Math;font-style:italic;font-weight:700;src:url(/lessons/25/katex/fonts/KaTeX_Math-BoldItalic.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Math-BoldItalic.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Math-BoldItalic.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Math;font-style:italic;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Math-Italic.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Math-Italic.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Math-Italic.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:normal;font-weight:700;src:url(/lessons/25/katex/fonts/KaTeX_SansSerif-Bold.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_SansSerif-Bold.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_SansSerif-Bold.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:italic;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_SansSerif-Italic.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_SansSerif-Italic.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_SansSerif-Italic.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_SansSerif-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_SansSerif-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_SansSerif-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Script;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Script-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Script-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Script-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size1;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Size1-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Size1-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Size1-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size2;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Size2-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Size2-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Size2-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size3;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Size3-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Size3-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Size3-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size4;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Size4-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Size4-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Size4-Regular.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Typewriter;font-style:normal;font-weight:400;src:url(/lessons/25/katex/fonts/KaTeX_Typewriter-Regular.woff2)format("woff2"),url(/lessons/25/katex/fonts/KaTeX_Typewriter-Regular.woff)format("woff"),url(/lessons/25/katex/fonts/KaTeX_Typewriter-Regular.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:"0.18.7"}.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{--background:#05080d;--ink:#f4f2ea;--acid:#d8ff63;--cyan:#75e6ff;--orange:#ff9f67}*{box-sizing:border-box}html,body{width:100%;height:100%;margin:0;overflow:hidden}body{background:var(--background);color:var(--ink);font-family:PingFang SC,Microsoft YaHei,sans-serif;font-size:35px}button,input,select{font:inherit}button{cursor:pointer}button:focus-visible,input:focus-visible{outline:3px solid var(--cyan);outline-offset:4px}button:disabled{opacity:.3}.deck-shell{background:#030609;position:fixed;inset:0;overflow:hidden}.stage{transform-origin:50%;background:radial-gradient(at 85% 15%,#12302c50,#0000 48%),#05080d;width:1600px;height:900px;padding:43px 64px 70px;position:absolute;top:50%;left:50%;overflow:hidden}.stage:before{content:"";pointer-events:none;background-image:linear-gradient(#ffffff06 1px,#0000 1px),linear-gradient(90deg,#ffffff06 1px,#0000 1px);background-size:64px 64px;position:absolute;inset:0;-webkit-mask-image:linear-gradient(#000,#0000);mask-image:linear-gradient(#000,#0000)}.slide-content{height:725px;padding-top:26px;animation:.3s ease-out appear;position:relative}h1{margin:25px 0;font-size:67px;font-weight:600;line-height:1.3}h2{margin:12px 0 24px;font-size:44px;font-weight:550;line-height:1.35}h3{margin:10px 0;font-size:35px}p{margin:14px 0;font-size:35px;line-height:1.5}.math{white-space:nowrap;font-size:40px;line-height:1.45;display:inline-block}.math .katex{font-size:1em}.cyan{color:var(--cyan)}.acid{color:var(--acid)}.orange{color:var(--orange)}.muted{color:#a9bcc4}.reveal{visibility:hidden;opacity:0;transition:opacity .25s,transform .25s;transform:translateY(7px)}.reveal.shown{visibility:visible;opacity:1;transform:none}.cover-art{pointer-events:none;width:1600px;height:900px;position:absolute;top:-115px;left:-64px}.cover-copy{z-index:1;padding-top:95px;position:relative}.cover-copy h1{letter-spacing:.03em;margin:48px 0 38px;font-size:96px}.cover-line{background:var(--acid);width:96px;height:4px}.cover-tag{color:#a9bcc4;margin-top:35px}.review-laws{flex-direction:column;width:1290px;margin:4px 45px 15px;display:flex}.review-laws>div{border-bottom:1px solid #ffffff25;align-items:center;gap:70px;padding:24px 12px;display:flex}.review-laws .math{font-size:60px}.review-bottom{grid-template-columns:700px 1fr;align-items:start;gap:12px;margin-top:34px;display:grid}.review-bottom h2{margin-top:0}.method-pair{grid-template-columns:1fr 1fr;gap:26px;display:grid}.method-pair>div{border-top:2px solid #ffffff30;padding-top:16px}.method-pair p{line-height:1.5}svg{overflow:visible}svg text{fill:var(--ink);font-family:PingFang SC,Microsoft YaHei,sans-serif;font-size:35px}@keyframes appear{0%{opacity:0;transform:translateY(7px)}to{opacity:1;transform:none}}@media (prefers-reduced-motion:reduce){*,:before,:after{transition:none!important;animation:none!important}}button{color:var(--ink);background:#12202b;border:1px solid #ffffff30;border-radius:9px;padding:8px 18px;font-size:35px}button[aria-pressed=true]{border-color:var(--acid);color:var(--acid);background:#d8ff6310}.split{grid-template-columns:900px 1fr;align-items:start;gap:36px;display:grid}.work{padding-top:20px}.work>.math,.work>.reveal>.math,.result>.math{margin:9px 0;font-size:37px;display:block}.work h2{color:var(--cyan);margin-top:0}.work p{line-height:1.45}.result{border-top:2px solid #75e6ff60;margin-top:20px;padding-top:14px}.result h2{font-size:35px}.data-strip{border-bottom:1px solid #fff2;justify-content:space-between;align-items:center;gap:20px;min-height:72px;margin-bottom:16px;font-size:35px;display:flex}.data-strip .math{font-size:37px}.legend{justify-content:center;gap:40px;font-size:35px;display:flex}.conditions{grid-template-columns:900px 1fr;align-items:center;gap:28px;margin-top:38px;display:grid}.condition-values{flex-direction:column;gap:45px;display:flex}.condition-values .math{font-size:38px}.question{text-align:center;margin:20px 0 12px;font-size:47px}.answer{text-align:center;font-size:40px}.answer span{margin-left:35px;font-size:35px}.two-questions{color:var(--cyan);border-top:1px solid #ffffff30;justify-content:center;gap:70px;margin-top:35px;padding-top:22px;font-size:35px;display:flex}.motion-layout{grid-template-columns:940px 470px;gap:60px;margin-top:20px;display:grid}.motion-heading{justify-content:space-between;align-items:center;margin:20px 0;display:flex}.motion-state{color:var(--orange);text-align:center;margin-top:35px;font-size:38px}.motion-timeline{color:#9fb0b8;align-items:center;gap:20px;margin:35px 0;font-size:35px;display:flex}.motion-timeline i{background:#fff2;flex:1;height:3px}.motion-timeline .active{background:var(--acid)}.snapshots{flex-direction:column;gap:5px;display:flex}.snapshot{border-top:1px solid #fff2;padding-top:10px;transition:opacity .3s}.snapshot>div{justify-content:space-between;font-size:35px;display:flex}.snapshot .math{font-size:35px}.snapshot.pending{opacity:.13}.snapshot svg{height:130px}.motion-question{margin-top:24px;font-size:41px}.formula-example{grid-template-columns:700px 740px;gap:32px}.formula-example .work{padding-top:0}.position-equation{align-items:center;gap:30px;margin-bottom:12px;font-size:35px;display:flex}.comparison{grid-template-columns:1fr 1fr;align-items:center;gap:12px;margin:15px 0;font-size:35px;display:grid}.comparison b{font-size:48px}.critical-top{justify-content:space-between;align-items:center;gap:25px;display:flex}.preset-row{gap:15px;display:flex}.critical-layout{grid-template-columns:650px 1fr;align-items:center;gap:30px;margin-top:20px;display:grid}table{border-collapse:collapse;width:100%;font-size:35px}th,td{text-align:center;white-space:nowrap;border-bottom:1px solid #ffffff25;padding:15px 14px}th{color:#b5c6cc;font-weight:500}td .math{font-size:35px}tr.selected{color:var(--acid);background:#d8ff6310}.critical-result{border-top:1px solid #d8ff6355;justify-content:center;align-items:center;gap:40px;padding-top:14px;font-size:35px;display:flex}.boundary-note{border-left:3px solid var(--acid);margin-top:20px;padding-left:22px;font-size:35px}.boundary-note p{margin:7px 0}.relative-strip{color:var(--orange);justify-content:center;align-items:center;gap:30px;margin-top:20px;font-size:35px;display:flex}.relative-strip i{background:#ff9f6770;width:90px;height:2px}.brake-top{gap:22px;display:flex}.brake-split .work{padding-top:0}.brake-split .work .math{font-size:35px}.brake-split .work p{margin:8px 0;font-size:35px}.brake-split .result{margin-top:8px;padding-top:8px}.experiment{grid-template-columns:420px 1000px;gap:48px;display:grid}.experiment-controls{border-right:1px solid #ffffff25;padding-right:25px}.car-inputs h2{margin:0 0 12px;font-size:35px}.experiment-controls label{justify-content:space-between;align-items:center;gap:10px;margin:9px 0;font-size:35px;display:flex}.experiment-controls input{width:108px;color:var(--ink);background:#0c141b;border:1px solid #ffffff35;border-radius:7px;padding:4px 8px;font-size:35px}.car-inputs{margin-bottom:20px}.experiment-presets{flex-direction:column;gap:9px;margin-top:20px;display:flex}.experiment-toolbar{align-items:center;gap:14px;display:flex}.experiment-toolbar .math{margin-left:auto;font-size:35px}.time-slider{width:100%;height:16px;accent-color:var(--acid);margin:8px 0 16px}.experiment-status{flex-direction:column;gap:8px;font-size:35px;line-height:1.35;display:flex}.experiment-status span{font-size:35px}.experiment-main .graph{margin-top:0}.experiment-main .graph text{font-size:35px}.source-button{color:#a9bcc4;background:0 0;padding:2px 16px;position:absolute;top:-56px;right:0}.source-dialog{width:min(92vw,1300px);max-height:90vh;color:var(--ink);background:#101a21;border:1px solid #75e6ff60;border-radius:12px;padding:24px}.source-dialog::backdrop{background:#000c}.source-dialog>button{float:right;margin-bottom:20px;position:sticky;top:0}.source-dialog>div{clear:both;overflow:auto}.source-dialog img{max-width:100%;margin:20px auto;display:block}.problem-stem{margin-top:2px;font-size:35px;line-height:1.5}.motorcycle-road{margin-top:8px}.motorcycle-split h2{margin-bottom:10px;font-size:35px;line-height:1.4}.motorcycle-split .math,.motorcycle-split p{margin:5px 0;font-size:35px}.process-strip{border-bottom:1px solid #fff2;justify-content:space-between;align-items:center;gap:18px;padding:8px 0 22px;display:flex}.process-strip>div{flex-direction:column;gap:9px;display:flex}.process-strip b,.process-strip span{font-size:35px;font-weight:500}.process-strip i{color:var(--acid);font-size:40px;font-style:normal}.multi-split .math{font-size:35px}.multi-split p{margin:10px 0;font-size:35px;line-height:1.45}.multi-foot{text-align:center;margin:0;font-size:35px;position:absolute;bottom:-4px;left:0;right:0}.bluetooth-initial{grid-template-columns:720px 1fr;align-items:center;gap:50px;margin-top:18px;display:grid}.bluetooth-initial>div:first-child>.math{text-align:center;display:block}.bluetooth-conditions>.math{margin:15px 0;font-size:38px;display:block}.bluetooth-conditions p{font-size:35px;line-height:1.55}.bluetooth-analysis{grid-template-columns:900px 1fr;gap:36px;display:grid}.bluetooth-analysis .work{padding-top:0}.bluetooth-analysis .work h2{margin:0 0 14px;font-size:35px}.bluetooth-analysis .work .math{margin:5px 0;font-size:35px}.bluetooth-analysis .work p{margin:5px 0;font-size:35px;line-height:1.35}.bluetooth-analysis .result{margin-top:9px;padding-top:9px}.connection-timeline{justify-content:center;gap:14px;font-size:35px;display:flex;position:absolute;bottom:-8px;left:0;right:0}.connection-timeline>span{border-radius:8px;padding:10px 22px}.connected{color:var(--acid);background:#d8ff6318}.disconnected{color:var(--orange);background:#ff9f6718}.summary-path{justify-content:center;align-items:center;gap:26px;margin:20px 0 45px;font-size:35px;display:flex}.summary-path i{color:var(--acid);font-style:normal}.summary-cards{grid-template-columns:repeat(3,1fr);gap:30px;display:grid}.summary-cards>div{background:#75e6ff04;border-top:2px solid #ffffff30;min-height:510px;padding:18px 15px}.summary-cards h2{margin:0 0 15px;font-size:40px}.summary-cards .math{font-size:38px;display:block}.summary-cards p{margin:12px 0;font-size:35px;line-height:1.5}.summary-end{text-align:center;color:var(--acid);border-top:1px solid #d8ff6350;margin-top:25px;padding-top:20px;font-size:42px}.page-5 .split{grid-template-columns:700px 740px;gap:32px}.page-5 .work>.math,.page-5 .work>.reveal>.math{font-size:35px}.page-4 .work{padding-top:10px}.page-4 .work p{margin:10px 0;line-height:1.35}.page-9 .work>.reveal>.math{line-height:1.25}.page-9 .work p{line-height:1.3}.page-9 .result{padding-top:6px}.motorcycle-road{height:165px}.motorcycle-split .work{padding-top:0}.motorcycle-split .work>.math,.motorcycle-split .result>.math{margin:6px 0;font-size:35px}.motorcycle-split .result{margin-top:14px;padding-top:10px}.multi-split{margin-top:8px}.multi-split .work{padding-top:15px}.multi-split .result>.math{margin:6px 0;font-size:36px}.multi-foot{font-size:35px;bottom:-5px}.process-strip{padding-bottom:12px}.process-strip .math{font-size:35px}.bluetooth-analysis .work p{margin:4px 0;line-height:1.3}.bluetooth-analysis .work .math{line-height:1.3}.connection-timeline{gap:20px;bottom:6px}.connection-timeline>span{padding:8px 22px}.experiment-controls label{margin:8px 0;line-height:1.2}.experiment-controls input{line-height:1.2}.experiment-presets button{padding:5px 12px}.relative-strip{gap:14px;margin-top:24px;font-size:35px}.relative-strip i{width:25px}.relative-strip span{white-space:nowrap}.page-9 .data-strip .math{font-size:35px}.page-12 .process-strip{padding-top:4px}.page-12 .data-strip>span{font-size:35px}.motorcycle-split .result p{font-size:35px;line-height:1.3}.physics-kicker{pointer-events:none}.connection-timeline{bottom:-18px}.cover-photo{object-fit:cover;opacity:.92}.cover-copy{width:790px;padding-top:120px}.cover-copy h1{text-shadow:0 4px 32px #000;font-size:94px}.cover-copy .cover-tag{max-width:680px}.cover-copy>p:first-child{font-size:35px}.example-stem{text-align:center;background:linear-gradient(90deg,#0000,#75e6ff06,#0000);border-bottom:1px solid #75e6ff45;min-height:123px;margin-bottom:22px;padding:7px 8px 18px;position:relative}.example-stem p{margin:3px 0;font-size:35px;line-height:1.48}.example-stem .math{font-size:35px}.stem-question{color:var(--orange);margin-left:18px}.example-stem p.stem-question{margin-left:0}.lesson-columns{align-items:start;gap:32px;display:grid}.graph-columns{grid-template-columns:820px 620px}.formula-columns{grid-template-columns:795px 645px}.step-pane{padding:6px 0 0}.step-pane h2{color:var(--cyan);margin:0 0 16px;font-size:38px;line-height:1.35}.step-pane p{margin:10px 0;font-size:35px;line-height:1.42}.step-pane>.math,.step-pane>.reveal>.math,.step-pane .result>.math{margin:7px 0;font-size:35px;line-height:1.48;display:block}.step-pane .result{margin-top:15px;padding-top:12px}.equation-row{border-left:2px solid #d8ff6370;flex-direction:column;gap:4px;margin:12px 0;padding-left:18px;display:flex}.equation-row>.math{font-size:35px}.intro-sketch{justify-content:center;min-height:200px;margin:8px 0 0;display:flex}.block-sketch text{font-size:var(--sketch-font,35px)}.sketch-note{text-align:center;padding-top:16px}.sketch-note p{font-size:35px;line-height:1.5}.graph-caption{text-align:center;margin:16px 0;font-size:35px;line-height:1.4}.vehicle-key{justify-content:center;gap:100px;font-size:35px;display:flex}.legend{gap:24px;margin:8px 0;font-size:35px}.diagram-reveal{animation:.45s both appear}.area-reveal{animation:.7s both areaIn}.draw-segment{stroke-dasharray:1;stroke-dashoffset:0;animation:1.2s cubic-bezier(.2,.6,.3,1) both drawLine}@keyframes drawLine{0%{stroke-dashoffset:1px}to{stroke-dashoffset:0}}@keyframes areaIn{0%{opacity:0}to{opacity:1}}.problem-sheet{border-left:3px solid var(--cyan);background:linear-gradient(110deg,#75e6ff09,#0000 78%);max-width:1370px;margin:32px auto 0;padding:25px 38px 28px}.problem-body p{margin:0 0 22px;font-size:38px;line-height:1.7}.problem-body .muted{font-size:35px}.problem-questions{color:var(--acid);border-top:1px solid #d8ff6360;margin-top:22px;padding-top:18px}.problem-questions p{margin:8px 0;font-size:38px;line-height:1.6}.problem-questions .muted{font-size:35px}.motion-teaching{grid-template-columns:760px 660px;gap:50px;margin-top:22px;display:grid}.motion-teaching h2{color:var(--cyan);margin:5px 0 20px;font-size:35px}.motion-teaching .motion-heading{min-height:56px;margin:0 0 16px}.motion-teaching .motion-state{margin:18px 0;font-size:35px}.motion-teaching>div:nth-child(2)>p{text-align:center;margin:5px 0;font-size:35px}.motion-teaching .block-sketch{overflow:visible}.critical-layout{grid-template-columns:590px 1fr;gap:30px;margin-top:14px}.critical-top{margin:4px 0 8px}.critical-layout th,.critical-layout td{padding:13px 10px}.boundary-note{margin-top:15px}.revision-process{margin-top:28px}.multi-sketch-row{grid-template-columns:850px 1fr;align-items:center;gap:70px;margin-top:38px;display:grid}.multi-sketch-row p{font-size:38px;line-height:1.8}.bluetooth-stem{min-height:126px}.bluetooth-stem p{font-size:35px}.bt-timeline{text-align:center;grid-template-columns:1.5fr 1fr 1.5fr;gap:10px;margin-top:10px;font-size:35px;display:grid}.bt-timeline span{border-top:3px solid var(--acid);color:var(--acid);background:#d8ff6308;padding:10px 0;line-height:1.4}.bt-timeline span:nth-child(2){color:var(--orange);border-color:var(--orange);background:#ff9f6708}.page-13 .problem-sheet{margin-top:15px}.page-13 .problem-body p{font-size:37px;line-height:1.68}.page-13 .step-pane h2{font-size:37px}.page-13 .step-pane p{margin:12px 0}.page-13 .step-pane>.math{margin:10px 0}.page-3 .question{margin:8px 0;font-size:43px}.page-3 .two-questions{margin-top:18px;padding-top:20px}.page-3 .answer{margin-top:10px;font-size:35px}.page-5 .step-pane .result>.math,.page-11 .graph-columns .step-pane h2,.graph-caption .math{font-size:35px}.tex-svg .tex-italic,.tex-letter{font-family:KaTeX_Math,Times New Roman,serif;font-style:italic}.tex-svg .tex-roman,.graph>g>text,.tex-axis,.tex-svg{font-family:KaTeX_Main,Times New Roman,serif}p .math,.problem-body .math,.problem-questions .math{font-size:inherit;line-height:inherit}.experiment-controls label>.math{font-size:35px}.preset-row button .math{font-size:35px;line-height:1.2}.equal-area-endpoints{border-top:1px solid #ffffff20;gap:35px;margin-top:15px;padding-top:20px;font-size:35px;display:flex}.equal-area-endpoints>div{gap:12px;display:grid}.equal-area-endpoints .math{font-size:35px}