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0}.formula-layout{display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:25px;margin-bottom:70px;align-items:start}.lesson,.aside,.practice-box{background:var(--card);border:1px solid var(--stroke);border-radius:20px;padding:32px;box-shadow:var(--shadow)}.lesson-top{display:flex;justify-content:space-between;align-items:center;gap:12px}.save-btn{background:var(--soft);color:var(--accent);border:0;border-radius:9px;padding:8px 12px;white-space:nowrap}.equation{background:linear-gradient(130deg,#f0f2ff,#f9f8ff);border:1px solid #e3e5ff;padding:22px;border-radius:14px;margin:28px 0;overflow-x:auto;color:#1c2450}.eq-label{font-size:11px;letter-spacing:1.5px;font-weight:900;color:#746cc5}.equation-text{font-size:clamp(21px,3vw,35px);font-family:Cambria,Georgia,serif;margin:12px 0 2px;white-space:nowrap}.calculator,.example,.explain{border-top:1px solid var(--stroke);padding-top:23px;margin-top:25px}.lesson h2{font-size:21px;margin:0 0 8px}.calculator p,.example p,.explain 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p{max-width:360px;color:#b5c0de;font-size:13px}.foot-grid>div{display:flex;flex-direction:column;gap:12px}.foot-grid strong{color:white}.foot-grid a:not(.brand),.foot-grid span:not(.brand-icon){font-size:13px;color:#c1cbee}.footer-bottom{border-top:1px solid #ffffff25;margin-top:32px;padding-top:16px;font-size:12px;color:#b7c3df}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0)}@media(max-width:920px){.classes{grid-template-columns:repeat(4,1fr)}.cards{grid-template-columns:repeat(2,minmax(0,1fr))}.topics{grid-template-columns:repeat(3,1fr)}.hero{padding:40px}.formula-layout{grid-template-columns:1fr}.aside{display:none}.hero-main{width:150px;height:150px;font-size:74px}}@media(max-width:650px){.container{width:min(100% - 28px,1210px)}.nav{min-height:67px}.brand-icon{width:40px;height:40px}.brand strong{font-size:15px}.brand 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/* MathJax rendering compatibility and responsive equation cards (v5).
   MathJax injects rules for SVG output. Its hidden assistive MathML must never
   be rendered visibly alongside the formula. */
mjx-assistive-mml {position:absolute!important;top:0!important;left:0!important;clip:rect(1px,1px,1px,1px)!important;clip-path:inset(50%)!important;width:1px!important;height:1px!important;overflow:hidden!important;padding:0!important;border:0!important;white-space:nowrap!important;pointer-events:none!important;}
mjx-container[jax="SVG"] {max-width:100%;}
.math-display,.equation-text {min-width:0;max-width:100%;overflow-x:auto;overflow-y:hidden;white-space:normal;overscroll-behavior-x:contain;-webkit-overflow-scrolling:touch;}
.math-display mjx-container,.equation-text mjx-container {max-width:none;min-width:max-content;}
.formula-card {overflow:hidden;}
@media(max-width:650px){.math-display{font-size:19px;padding:12px 0}.equation-text{font-size:clamp(20px,5vw,29px)}}

/* Third-party licensing: accessible, responsive long-form notices */
.license-page{max-width:100%;overflow-wrap:anywhere}
.license-page .license-panel{background:var(--surface,#f3f6ff);border:1px solid var(--border,#d7def1);padding:1rem 1.25rem;border-radius:14px;margin:1.2rem 0}
.license-page .license-panel p{margin:.65rem 0}
.license-page .primary{display:inline-block;max-width:100%;white-space:normal;overflow-wrap:anywhere}
.license-page .full-license{overflow:auto;white-space:pre-wrap;overflow-wrap:anywhere;word-break:normal;font-size:.78rem;line-height:1.55;max-height:72vh;background:#f5f7fc;color:#1a2340;border:1px solid #dbe1ef;border-radius:12px;padding:1rem}
@media(max-width:600px){.license-page .full-license{font-size:.72rem;padding:.65rem}.license-page .license-panel{padding:.8rem}}