:root{color-scheme:dark;--bg:#080c13;--panel:#0e141f;--panel-hover:#131d2b;--line:#202936;--text:#f2f5fa;--muted:#929caa;--blue:#65adff;--cyan:#66d6f0;--purple:#a7a0f5;--radius:18px;--sans:Inter,"Segoe UI",Arial,sans-serif;--mono:"SFMono-Regular",Consolas,"Liberation Mono",monospace}
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.lab-section{background:radial-gradient(ellipse at 20% 70%,#10244566,transparent 55%),#0a101a}.lab-layout{display:grid;grid-template-columns:1fr 1fr;gap:110px;align-items:center}.lab-copy h2{font-size:45px;line-height:1.2;margin:18px 0 22px}.lab-copy>p{font-size:13px;color:#8495ae;line-height:1.9;max-width:345px}.capacitor-diagram{max-width:360px;margin:12px 0 20px}.capacitor-diagram>span{display:block;text-align:center;font:8px var(--mono);letter-spacing:1.7px;color:#506b8b}.lab-hint{display:flex;gap:17px;align-items:flex-start;border-top:1px solid #233148;padding-top:20px;max-width:355px}.lab-hint>span{font:8px/1.8 var(--mono);letter-spacing:1px;color:#6f9ed5;flex-shrink:0;padding-top:2px}.lab-hint p{font-size:11px;line-height:1.8;color:#7c90ac;margin:0}.lab-hint strong{color:#c3daf3;font-weight:500}.calculator{border:1px solid #344969;border-radius:16px;background:linear-gradient(125deg,#142033,#0c1422);padding:25px 28px 21px;box-shadow:0 25px 60px #03080f55,0 1px 0 #8abfff0c inset}.calculator-header{display:flex;align-items:center;gap:8px;font:8px var(--mono);letter-spacing:1.3px;color:#97b3d5;margin-bottom:23px}.calculator-header .status-dot{width:5px;height:5px}.calculator-header>.mono{margin-left:auto;color:#48688e;letter-spacing:0}.calc-tabs{display:flex;background:#080f1c;border:1px solid #203149;border-radius:8px;padding:4px;margin-bottom:23px}.calc-tabs button{flex:1;border:1px solid transparent;border-radius:5px;font:11px var(--mono);padding:9px 6px;background:none;color:#738eaf}.calc-tabs button.active{background:#203755;border-color:#365b83;color:#c4e3ff;box-shadow:0 2px 5px #0003}.input-group{margin-top:15px}.input-group label{display:block;color:#9eb1cc;font-size:11px;margin-bottom:8px}.unit-input{display:flex;height:49px;border:1px solid #2d4260;border-radius:7px;background:#0a1321;overflow:hidden}.unit-input:focus-within{border-color:var(--blue)}.unit-input input{flex:1;min-width:0;background:none;color:#d9eaff;border:0;padding:0 15px;font:19px var(--mono);outline:none}.unit-input select{background:#142136;border:0;border-left:1px solid #2d4260;color:#9cbfe7;padding:0 11px;width:84px;font:12px var(--mono)}.calculate-button{width:100%;margin-top:22px;justify-content:space-between}.form-error{font-size:11px;color:#ffbdc9;line-height:1.6;margin:10px 0 0}.calc-result{margin-top:24px;border-top:1px solid #304564;padding-top:21px}.calc-result.is-stale{opacity:.45}.result-label{display:flex;justify-content:space-between;align-items:center;gap:12px;color:#7091bb;font:8px var(--mono);letter-spacing:1.1px}.result-label span{font:10px var(--mono);letter-spacing:0;color:#799dc7}.energy-value{font:51px/1.3 var(--mono);letter-spacing:-2px;color:#c2e2ff;margin:13px 0 6px;overflow-wrap:anywhere}.energy-value span{font-size:26px;color:#7ea8d5;letter-spacing:-1px}.calc-result>p{font:10px/1.7 var(--mono);color:#718eaf;overflow-wrap:anywhere;margin:8px 0 16px}.result-other{display:flex;flex-wrap:wrap;gap:15px;font:9px var(--mono);color:#a3bbd8}.result-other span{background:#1b2a4055;border:1px solid #2b405b;padding:5px 8px;border-radius:4px}.calc-footnote{font-size:9px;color:#627d9e;margin-top:19px;line-height:1.7}
.practice-section{padding-top:82px;padding-bottom:78px;background:#080c13}.practice-panel{position:relative;overflow:hidden;display:grid;grid-template-columns:1.2fr 1fr;background:radial-gradient(ellipse at 90% 30%,#153e75aa,transparent 66%),linear-gradient(125deg,#111e30,#0c1626);border:1px solid #344b6b;border-radius:18px;min-height:390px}.practice-main{padding:43px 45px;z-index:1}.practice-main .eyebrow{font-size:9px;color:#739ecf}.practice-main h2{font-size:40px;margin:18px 0 18px;line-height:1.2}.practice-main h2 span{color:#93c6ff}.practice-main>p{font-size:12px;color:#859dbb;line-height:1.8}.practice-controls{display:flex;gap:10px;margin-top:25px;flex-wrap:wrap}.practice-controls select{border:1px solid #375273;background:#101e32;border-radius:8px;color:#bdd0e8;font-size:11px;padding:0 33px 0 13px;min-height:46px;max-width:100%}.practice-note{font-size:9px;color:#657f9f;margin-top:15px}.practice-art{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;isolation:isolate}.practice-number{font:120px/.95 var(--sans);font-weight:300;letter-spacing:-7px;background:linear-gradient(170deg,#ddf1ff 12%,#629fdf 58%,#345e95 95%);background-clip:text;-webkit-text-fill-color:transparent;text-align:center;padding-right:7px}.practice-number>span{display:block;font:9px var(--mono);letter-spacing:8px;color:#78a8de;-webkit-text-fill-color:#78a8de;margin-top:23px;padding-left:10px}.goal-caption{margin-top:28px;text-align:center;color:#688ab4;font-size:10px;line-height:1.8}.practice-orbit{position:absolute;border:1px solid #4875b332;border-radius:50%;height:310px;width:310px;z-index:-1;top:35px;left:50%;transform:translateX(-50%)}.orbit-b{width:360px;height:360px;top:10px;border-style:dashed;border-color:#4875b322}.orbit-a::before{content:'';position:absolute;width:5px;height:5px;border-radius:50%;background:#92cbff;box-shadow:0 0 12px #60adff;top:56px;left:32px}.progress-strip{display:flex;align-items:center;gap:14px;padding:23px 7px 0}.progress-icon{background:#132136;color:#72acf1;font:20px var(--mono);width:35px;height:35px;display:grid;place-items:center;border:1px solid #273d5a;border-radius:50%;flex-shrink:0}.progress-strip strong{font-size:11px;color:#a1b4ce;font-weight:500}.progress-strip p{font-size:10px;color:#5a708e;margin:3px 0 0}.text-button{background:none;border:0;padding:4px 0;border-bottom:1px solid #405371;color:#8fa8c9;font-size:10px;margin-left:auto;white-space:nowrap}.text-button:hover{color:#c8e2ff}.closing-section{border-top:1px solid #1c2b3e;border-bottom:1px solid #1c2b3e;padding:47px 0;background:linear-gradient(100deg,#0e1723,#0a111c)}.closing-inner{display:flex;justify-content:space-between;align-items:center}.closing-brand h2{font-size:29px;letter-spacing:-1px;line-height:1.3;font-weight:500;margin-top:12px;color:#becbde}.closing-brand .eyebrow{font-size:8px}.round-link{width:64px;height:64px;border:1px solid #304864;border-radius:50%;display:grid;place-items:center;font-size:30px;color:#89b5eb;transition:background .2s}.round-link:hover{background:#1c3251}.site-footer{padding:30px 0 26px;background:#070b12}.footer-inner{display:flex;align-items:center;justify-content:space-between;gap:20px}.footer-brand{font-size:13px;letter-spacing:2px;gap:7px}.footer-brand>span{font:8px var(--mono);color:#7891b0;letter-spacing:1px}.footer-inner>p{font-size:10px;color:#61718a;margin:0}.footer-inner>a:last-child{font-size:10px;color:#91a6c1}.footer-inner>a:last-child span{margin-left:13px;font-size:16px}.footer-note{font-size:9px;color:#4e627d;margin-top:22px;border-top:1px solid #182334;padding-top:16px;line-height:1.9}
.icon-button{background:none;border:1px solid #2c405d;display:inline-grid;place-items:center;min-width:34px;height:34px;border-radius:7px;padding:6px;color:#91a9c9}.icon-button:hover{background:#233951;color:#d9ecff}.content-dialog{background:#101a29;color:var(--text);border:1px solid #38506f;border-radius:18px;width:620px;max-width:calc(100vw - 32px);max-height:calc(100dvh - 48px);padding:28px;box-shadow:0 40px 150px #000b;overscroll-behavior:contain}.content-dialog::backdrop{background:#02060ec7;backdrop-filter:blur(7px)}.dialog-top{display:flex;justify-content:space-between;align-items:center;gap:20px;margin-bottom:23px}.dialog-top .eyebrow{font-size:9px}.content-dialog h2{font-size:31px;line-height:1.25;letter-spacing:-1px;margin:0 0 14px}.topic-intro{color:#99aec9;font-size:13px;line-height:1.9}.principle{background:#152943;border-left:2px solid #6cb4ff;padding:14px 17px;color:#b2cdeb;font-size:12px;line-height:1.85;margin:20px 0}.dialog-formulas{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin:20px 0}.dialog-formula{background:#0b1320;border:1px solid #2a3c56;border-radius:8px;padding:12px}.dialog-formula span{display:block;color:#7e97ba;font-size:9px;margin-bottom:9px}.dialog-formula strong{font:17px var(--mono);color:#d5e9ff}.worked-example{margin-top:26px;border-top:1px solid #2b3f5b;padding-top:22px}.worked-example h3{font-size:15px;margin:8px 0 12px}.worked-example>p{font-size:12px;color:#9eb2cd;line-height:1.9}.worked-example ol{padding-left:23px;color:#b3c8e2;font-size:12px;line-height:1.9}.worked-example li{padding:5px 0 5px 7px}.example-answer{font:21px var(--mono);color:#a4d2ff;background:#15283e;padding:15px;border-radius:8px;margin-top:17px}.topic-start{margin-top:22px;width:100%}.quiz-progress{display:flex;justify-content:space-between;font:10px var(--mono);color:#7fa5d0;margin:3px 0 13px}.quiz-progress-bar{height:3px;background:#253852;border-radius:4px;margin-bottom:25px;overflow:hidden}.quiz-progress-bar span{display:block;height:100%;background:#92c9ff;transition:width .3s}.quiz-dialog h2{font-size:23px;line-height:1.5;letter-spacing:-.5px;margin-bottom:22px}.quiz-options{display:grid;gap:10px}.quiz-option{display:flex;align-items:center;text-align:left;gap:15px;background:#0c1523;border:1px solid #2c405c;border-radius:8px;padding:13px 15px;color:#adc3e0;font-size:13px;line-height:1.6}.quiz-option:disabled{cursor:default;opacity:1}.option-letter{display:grid;place-items:center;border:1px solid #3c5679;min-width:26px;height:26px;border-radius:5px;font:10px var(--mono);color:#8daace}.quiz-option[aria-pressed=true]{border-color:#86bfff;background:#1b3353;color:#e0f0ff}.quiz-option.correct{border-color:#64c5b8;background:#133333;color:#b1e6dd}.quiz-option.incorrect{border-color:#d284a0;background:#352132;color:#f0b5ca}.quiz-feedback{margin-top:19px;padding:16px;border:1px solid #355973;border-radius:8px;background:#11273b}.quiz-feedback strong{font-size:12px;color:#c3defa}.quiz-feedback p{margin:7px 0 0;color:#9bb9d9;font-size:12px;line-height:1.8}.quiz-next{margin-top:21px;width:100%;justify-content:space-between}.quiz-score{text-align:center;padding:10px 0 20px}.score-big{font:76px/1.2 var(--mono);color:#abd5ff;letter-spacing:-5px}.score-big span{font-size:27px;color:#53749e;letter-spacing:-1px}.quiz-score h2{font-size:26px;margin:18px 0 10px}.quiz-score p{font-size:12px;color:#8ca6c8;line-height:1.8}.score-actions{display:flex;justify-content:center;gap:12px;margin-top:25px;flex-wrap:wrap}.review-item{border-top:1px solid #2d405b;padding:17px 0}.review-item strong{font-size:12px;color:#cee2fa;font-weight:500;line-height:1.7;display:block}.review-item p{font-size:11px;line-height:1.8;margin:8px 0 0;color:#8facca}.review-item .answer-status{font:9px var(--mono);display:block;margin-bottom:6px;color:#91c5ff}.reset-dialog{width:430px;padding:30px}.reset-dialog h2{font-size:24px}.reset-dialog>p{font-size:12px;color:#8ea8c9}.reset-actions{display:flex;justify-content:flex-end;gap:10px;margin-top:25px}.toast{position:fixed;z-index:80;bottom:28px;left:50%;transform:translate(-50%,15px);opacity:0;pointer-events:none;border:1px solid #4d719b;background:#172b44;box-shadow:0 8px 30px #0009;border-radius:8px;padding:12px 20px;color:#c9e4ff;font-size:12px;max-width:calc(100vw - 30px);text-align:center;transition:opacity .2s,transform .2s}.toast.visible{opacity:1;transform:translate(-50%,0)}.noscript-note{padding:20px;text-align:center;background:#1c334f;color:#d4eaff}
@keyframes float{0%,100%{transform:translateY(0)}50%{transform:translateY(-10px)}}
@media(min-width:1450px){.hero-inner{min-height:690px}.hero-art{height:590px}.hero h1{font-size:108px}}
@media(max-width:1150px){.container{width:calc(100% - 64px)}.desktop-nav{gap:18px;margin-left:0}.header-inner{gap:20px}.desktop-nav a{font-size:12px}.header-cta{gap:12px;font-size:11px}.hero-inner{min-height:605px;grid-template-columns:1fr 1fr}.hero h1{font-size:83px}.hero-art{height:470px;margin-left:-40px;margin-right:-30px}.hero-copy>p{font-size:13px}.hero-actions{gap:16px}.hero-actions .button{gap:13px}.text-link{font-size:11px}.equation-one{right:4px;top:97px}.equation-two{left:10px;bottom:85px}.art-caption{left:24%;bottom:-8px}.lab-layout{gap:65px}.section{padding:78px 0}.practice-main{padding:35px}.practice-number{font-size:104px}.practice-orbit{height:270px;width:270px;top:49px}.orbit-b{height:320px;width:320px;top:24px}.hero-bottom{gap:35px}.formula-expression{font-size:22px}}
@media(max-width:900px){.desktop-nav{display:none}.header-cta{margin-left:auto}.mobile-toggle{display:inline-grid!important}.header-inner{height:77px}.brand{font-size:18px}.hero h1{font-size:76px;letter-spacing:-4px}.hero-inner{min-height:580px;grid-template-columns:1.1fr 1fr}.hero-art{height:410px;margin-left:-60px;margin-right:-35px}.hero-art .floating-equation{font-size:18px;padding:10px 14px}.floating-equation>span:first-child{font-size:7px}.fraction{font-size:15px}.equation-one{right:0;top:75px}.equation-two{left:20px;bottom:65px}.art-caption{left:24%;font-size:9px;bottom:-25px;gap:5px}.art-bars{display:none}.coordinate-top{right:0;top:5px}.hero-copy .eyebrow{font-size:8px;letter-spacing:1px}.hero-actions{gap:18px;align-items:flex-start;flex-direction:column}.hero-note{font-size:9px}.hero-bottom{gap:25px}.hero-bottom>div{gap:8px}.hero-bottom div span{font-size:9px}.scroll-cue{font-size:8px;gap:12px}.hero-bottom strong{font-size:20px}.section-heading h2{font-size:34px}.section-heading>p{font-size:11px}.topic-card{padding:21px 19px;min-height:180px}.topic-card h3{font-size:15px}.topic-card p{font-size:10px}.topic-arrow{right:19px;bottom:21px}.formula-grid{grid-template-columns:repeat(2,1fr)}.formula-card>p{min-height:17px}.lab-layout{gap:35px}.lab-copy h2{font-size:38px}.calculator{padding:23px 21px}.lab-hint{flex-direction:column;gap:6px}.calculator-header{font-size:7px;letter-spacing:.6px}.practice-panel{grid-template-columns:1.3fr 1fr}.practice-main{padding:35px 28px}.practice-main h2{font-size:33px}.practice-main>p{font-size:11px}.practice-number{font-size:90px}.practice-number>span{font-size:8px;letter-spacing:6px}.practice-orbit{width:245px;height:245px;top:70px}.orbit-b{width:290px;height:290px;top:47px}.goal-caption{font-size:9px}.footer-inner{flex-wrap:wrap}.footer-inner>p{font-size:9px}.footer-brand{font-size:12px}}
@media(max-width:650px){html{scroll-padding-top:84px}.container{width:calc(100% - 40px)}.header-inner{height:72px;gap:16px}.brand{font-size:17px;gap:9px;letter-spacing:2.5px}.brand svg{width:30px;height:30px}.brand-sub{font-size:7px;letter-spacing:3.9px}.header-cta{font-size:9px;padding:7px 10px;gap:8px}.header-cta>span{font-size:16px}.mobile-toggle{min-width:31px;height:31px}.hero-inner{grid-template-columns:1fr;padding-top:39px;padding-bottom:0;min-height:0}.hero-copy{padding:0}.hero h1{font-size:76px;line-height:1.02;margin:23px 0;letter-spacing:-4px}.hero-copy>p{font-size:13px;max-width:360px;margin-bottom:25px}.hero-actions{flex-direction:row;gap:20px;align-items:center}.hero-actions .button{font-size:11px;padding:11px 14px}.text-link{font-size:10px;gap:9px}.hero-note{margin-top:21px}.hero-copy .eyebrow{font-size:8px;letter-spacing:1.3px}.hero-art{height:365px;margin:0 -15px -1px 0;width:100%;max-width:470px;justify-self:center}.orbital{width:105%;left:-2.5%}.floating-equation{backdrop-filter:blur(5px)}.equation-one{right:13px;top:68px}.equation-two{left:15px;bottom:80px}.coordinate-top{top:19px;right:15px;font-size:7px}.art-caption{bottom:11px;left:29%;font-size:9px;gap:9px}.hero-bottom{padding:20px 0;gap:0;justify-content:space-between;align-items:flex-start}.hero-bottom>div{display:flex;flex-direction:column;gap:2px}.hero-bottom strong{font-size:21px}.hero-bottom div span{font-size:9px}.scroll-cue{display:none}.section{padding:59px 0}.section-heading{display:block;margin-bottom:27px}.section-heading h2{font-size:33px;letter-spacing:-1.1px;margin-top:13px}.section-heading>p{margin-top:18px;font-size:12px;line-height:1.8}.desktop-break{display:none}.eyebrow{font-size:9px;letter-spacing:1.4px}.topic-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.topic-card{padding:19px 16px;min-height:180px}.topic-card-top{margin-bottom:25px}.topic-card h3{font-size:14px;letter-spacing:-.35px;line-height:1.5;padding-right:3px}.topic-card p{font-size:9px;padding-right:15px;line-height:1.6;max-width:130px}.topic-arrow{right:14px;bottom:17px;font-size:19px}.topic-icon svg{width:29px;height:29px}.topic-number{font-size:8px}.learning-strip{gap:10px;align-items:flex-start;padding-top:18px}.learning-strip p{font-size:10px;line-height:1.9}.learning-strip svg{margin-top:4px;width:15px;height:15px}.learning-strip>span{display:none}.formula-toolbar{gap:9px;margin-top:24px}.search-wrap{padding:0 11px;gap:8px}.search-wrap input{font-size:11px;height:45px}.search-wrap kbd{display:none}.search-wrap svg{width:16px;height:16px}.saved-button{min-width:0;font-size:0;padding:9px 12px;gap:7px}.saved-button svg{width:15px;height:15px}.saved-button>span{font-size:9px}.filter-row{gap:3px;margin-top:17px}.filter-chip{font-size:10px;padding:5px 8px}.formula-grid{gap:10px}.formula-card-top{padding:12px 13px 0;gap:6px}.formula-tag{font-size:8px;padding:3px 5px}.save-formula{padding:5px;width:25px;height:25px}.formula-expression{padding:18px 14px;font-size:19px;letter-spacing:-1px;min-height:75px;overflow-wrap:anywhere}.formula-card h3{font-size:11px;margin:0 14px 6px;line-height:1.6}.formula-card>p{font-size:9px;margin:0 14px 13px;line-height:1.7;min-height:31px}.formula-card summary{font-size:9px;padding:9px 14px;gap:6px}.formula-card details p{font-size:9px;padding:0 14px 12px;line-height:1.8}.result-meta{font-size:8px}.center .button{font-size:11px;min-height:42px}.lab-layout{grid-template-columns:1fr;gap:33px}.lab-copy h2{font-size:37px;margin:14px 0 18px}.lab-copy>p{font-size:12px;max-width:100%}.capacitor-diagram{width:260px;margin:6px auto 22px}.capacitor-diagram>span{font-size:7px}.lab-hint{max-width:none;flex-direction:row;gap:16px}.lab-hint>span{font-size:7px}.lab-hint p{font-size:10px}.calculator{padding:22px;border-radius:13px}.calculator-header{font-size:8px;letter-spacing:1px}.energy-value{font-size:48px}.practice-panel{grid-template-columns:1fr;min-height:0}.practice-main{padding:30px 24px 10px}.practice-main h2{font-size:33px}.practice-main>p{font-size:12px}.practice-main .eyebrow{font-size:8px;letter-spacing:1px}.practice-controls{flex-wrap:nowrap;gap:8px}.practice-controls select{font-size:10px;padding:0 10px;min-width:0;flex:1}.practice-controls .button{font-size:10px;padding:10px 12px;gap:16px}.practice-note{font-size:8px}.practice-art{min-height:285px;margin-top:16px;overflow:hidden}.practice-number{font-size:103px}.practice-number>span{font-size:8px;letter-spacing:6px;margin-top:17px}.practice-orbit{top:6px;width:235px;height:235px}.orbit-b{top:-16px;width:280px;height:280px}.goal-caption{margin-top:23px;font-size:9px}.progress-strip{align-items:flex-start;padding-top:20px;gap:11px;flex-wrap:wrap}.progress-icon{width:30px;height:30px;font-size:17px;margin-top:3px}.progress-strip>div{flex:1;min-width:200px}.progress-strip strong{font-size:10px;line-height:1.8;display:block}.progress-strip p{font-size:9px;line-height:1.8}.progress-strip .text-button{margin-left:41px}.closing-section{padding:35px 0}.closing-brand h2{font-size:26px}.round-link{width:52px;height:52px;font-size:25px}.footer-inner{display:grid;grid-template-columns:1fr auto;gap:16px}.footer-brand{font-size:11px;letter-spacing:1px}.footer-brand>span{font-size:7px}.footer-inner>p{grid-row:2;grid-column:1/-1;font-size:9px}.footer-inner>a:last-child{font-size:9px}.footer-inner>a:last-child span{margin-left:5px}.footer-note{font-size:8px;margin-top:16px}.content-dialog{padding:23px 20px;max-height:calc(100dvh - 30px);max-width:calc(100vw - 22px);border-radius:13px}.content-dialog h2{font-size:26px}.topic-intro{font-size:12px}.principle{font-size:11px;padding:13px}.dialog-formula{padding:10px}.dialog-formula strong{font-size:15px}.worked-example ol{padding-left:19px;font-size:11px}.worked-example>p{font-size:11px}.quiz-dialog h2{font-size:19px}.quiz-option{font-size:12px;padding:11px;gap:11px}.quiz-feedback p{font-size:11px}.dialog-top{margin-bottom:20px}.quiz-score h2{font-size:24px}.score-big{font-size:65px}.score-actions .button{font-size:10px;gap:10px}.reset-dialog h2{font-size:23px}.reset-actions .button{font-size:11px}.toast{font-size:11px;bottom:18px;padding:11px 15px}}
@media(max-width:370px){.container{width:calc(100% - 30px)}.header-cta{display:none}.mobile-toggle{margin-left:auto}.hero h1{font-size:65px}.hero-actions{gap:13px}.hero-actions .button{padding:11px;font-size:10px}.text-link{font-size:9px}.hero-art{height:325px}.equation-two{bottom:73px}.hero-bottom div span{font-size:8px}.topic-card{padding:17px 12px}.topic-card h3{font-size:12px}.formula-expression{font-size:17px}.formula-card h3{font-size:10px}.practice-main{padding:26px 20px 10px}.practice-controls{flex-wrap:wrap}.practice-controls select{width:100%;flex:auto;height:43px}.practice-controls .button{width:100%}.calculator-header{font-size:7px}.calculator{padding:19px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{animation:none!important;transition:none!important}}
.practice-number b{font-weight:inherit}.share-formula{border:0;background:none;color:#6688b1;font:19px var(--mono);padding:3px;margin-left:auto;line-height:1}.share-formula:hover{color:#c1e0ff}.formula-card-top{gap:6px}.formula-tag{margin-right:auto}.footer-extra{display:flex;justify-content:flex-end;gap:24px;font-size:10px;color:#7d9bbe;margin-top:16px}.material-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.material-card{display:flex;flex-direction:column;gap:13px;padding:26px;background:#101a29;border:1px solid #2b405b;border-radius:12px}.material-card:hover{border-color:#658eba;background:#162438}.material-card h3{font-size:19px;line-height:1.5;letter-spacing:-.4px;margin:0;font-weight:500}.material-card p{font-size:12px;line-height:1.9;color:#91a8c5;margin:0;white-space:pre-line;overflow-wrap:anywhere}.material-card .text-link{margin-top:auto;padding-top:9px;font-size:11px}.materials-section{border-top:1px solid #25374e;background:#0c131f}.reading-page{max-width:800px;margin:0 auto;padding:55px 24px 80px}.reading-page h1{font-size:43px;font-weight:550;line-height:1.3;letter-spacing:-1.5px;margin:26px 0}.reading-page h2{font-size:25px;letter-spacing:-.6px;margin:30px 0 15px}.reading-page p,.reading-page li{font-size:15px;line-height:1.95;color:#a9bed9}.reading-page .article-body{white-space:pre-wrap;overflow-wrap:anywhere}.reading-page .read-back{font-size:12px;color:#86baff}.reading-page .dialog-formulas{grid-template-columns:repeat(2,minmax(0,1fr))}.reading-page .principle{font-size:14px}.reading-page .example-answer{margin-bottom:25px}.reading-page .topic-links{display:flex;flex-wrap:wrap;gap:15px;margin-top:35px;border-top:1px solid #2d435e;padding-top:20px;font-size:11px;color:#79a6dc}
@media(max-width:750px){.material-grid{grid-template-columns:repeat(2,1fr)}.material-card{padding:21px}.material-card h3{font-size:17px}.reading-page h1{font-size:34px}.reading-page p,.reading-page li{font-size:13px}.reading-page .principle{font-size:12px}}
@media(max-width:480px){.material-grid{grid-template-columns:1fr}.formula-tag{font-size:7px}.formula-card-top{gap:3px}.share-formula{font-size:17px;padding:2px}.reading-page{padding-top:35px}.reading-page h1{font-size:30px}.reading-page .dialog-formula strong{font-size:16px}}