.calculus-page{background:var(--cream)}
.calc-hero{display:grid;gap:30px;padding:46px 0 54px;align-items:center}.calc-hero h1{font:700 clamp(39px,9vw,66px)/1.03 'Fredoka';margin:12px 0 20px;letter-spacing:-.03em}.calc-hero h1 em{color:var(--purple);font-style:normal}.hero-copy>p:not(.eyebrow){max-width:670px;color:var(--muted);font-size:17px}.hero-actions{display:flex;align-items:center;gap:18px;flex-wrap:wrap;margin:26px 0 18px}.text-link{color:var(--purple);font-weight:800}.hero-facts{display:flex;gap:8px;flex-wrap:wrap}.hero-facts span{padding:7px 10px;border:1px solid var(--line);border-radius:999px;background:#fff;font-size:12px;font-weight:700}.hero-image{margin:0;padding:10px;background:#fff;border:1px solid var(--line);border-radius:24px;box-shadow:var(--shadow)}.hero-image img{display:block;width:100%;height:auto;aspect-ratio:2/1;object-fit:cover;border-radius:17px}.hero-image figcaption{padding:9px 5px 2px;color:var(--muted);font-size:12px;text-align:center}
.lesson-nav{display:grid;grid-template-columns:repeat(2,1fr);gap:8px;padding-bottom:34px}.lesson-nav a{display:flex;align-items:center;gap:8px;padding:12px;background:#fff;border:1px solid var(--line);border-radius:13px;color:var(--ink);font-size:12px;font-weight:800;text-decoration:none}.lesson-nav b{color:var(--purple)}
.section{padding:70px 0;scroll-margin-top:40px}.section-heading{max-width:800px;margin-bottom:30px}.section-heading h2,.split-heading h2,.lab-copy h2,.next-section h2{font:700 clamp(34px,7vw,52px)/1.08 'Fredoka';margin:7px 0 12px}.section-heading>p:last-child,.split-heading>div>p:last-child,.lab-copy>p,.next-section>div>p:last-child{color:var(--muted)}.idea-grid{display:grid;gap:14px}.idea-grid article{padding:25px;background:#fff;border:1px solid var(--line);border-radius:22px}.idea-icon{display:grid;place-items:center;width:45px;height:45px;border-radius:14px;font-size:25px;font-weight:800}.idea-icon.coral{background:#ffe4df;color:#e65f4c}.idea-icon.mint{background:#dcf7ed;color:#248267}.idea-grid h3{font:700 26px 'Fredoka';margin:16px 0 7px}.idea-grid p{color:var(--muted)}.idea-grid small{font-weight:800;color:var(--purple)}.connection{display:flex;align-items:center;justify-content:center;gap:9px;flex-wrap:wrap;margin-top:20px;padding:18px;background:#262144;color:#fff;border-radius:18px}.connection span{padding:7px 10px;background:#5b4bdb;border-radius:9px;font-weight:800}.connection i{color:#c8c3e7;font-size:12px}
.soft-section{background:#f1effa}.foundation-grid,.rules-grid,.integral-grid,.practice-grid{display:grid;gap:13px}.foundation-grid article{padding:21px;background:#fff;border-radius:18px}.foundation-grid b{font:700 24px 'Fredoka';color:var(--purple)}.foundation-grid h3{margin:9px 0 5px}.foundation-grid p{margin:0;color:var(--muted);font-size:14px}.split-heading{display:grid;gap:24px;margin-bottom:30px}.formula-card{display:flex;flex-direction:column;justify-content:center;padding:25px;background:#fff;border:1px solid var(--line);border-radius:22px;box-shadow:var(--shadow)}.formula-card small{color:var(--muted)}.formula-card strong{font:700 clamp(25px,6vw,38px) 'Fredoka';color:var(--purple);margin:9px 0}.formula-card span{font-size:13px}.formula-card.green strong{color:#248267}.explain-grid{display:grid;gap:18px}.explain-grid h3,.worked-example h3{font:700 27px 'Fredoka';margin:6px 0 10px}.explain-grid p{color:var(--muted)}.analogy{display:flex;gap:12px;padding:16px;background:#fff4c9;border-radius:15px}.analogy span{font-size:28px}.analogy p{margin:0;color:#63541c}.worked-example{padding:23px;background:#fff;border:1px solid var(--line);border-radius:20px}.worked-example .math{font:700 24px 'Fredoka';color:var(--purple)}.worked-example li{margin:8px 0;color:var(--muted)}
.purple-section{background:var(--purple);color:#fff}.section-heading.light>p:last-child{color:#dedaff}.purple-section .eyebrow,.quiz-section .eyebrow{color:#d7d2ff}.definition-card{display:flex;flex-direction:column;padding:22px;background:#fff;color:var(--ink);border-radius:20px}.definition-card strong{font:700 clamp(19px,4.7vw,31px) 'Fredoka';color:var(--purple);margin:8px 0;overflow-wrap:anywhere}.definition-card small,.definition-card span{color:var(--muted)}.rules-grid{margin-top:16px}.rules-grid article{padding:19px;background:#ffffff14;border:1px solid #ffffff2b;border-radius:17px}.rules-grid small{color:#d8d3ff}.rules-grid b{display:block;margin:7px 0;font:700 19px 'Fredoka'}.rules-grid p{margin:0;color:#e3e0f4;font-size:13px}.dark-example{margin-top:16px;background:#2b2552;border-color:#ffffff28}.dark-example p{color:#ddd9ee}.dark-example .eyebrow{color:#fff1ad}
.lab-section{display:grid;gap:24px;align-items:center}.lab-copy label{display:block;margin:24px 0 9px;font-weight:800}.lab-copy output{color:var(--purple)}input[type=range]{width:100%;accent-color:var(--purple)}.live-result{display:flex;justify-content:space-between;align-items:center;margin-top:12px;padding:14px 17px;background:#fff;border:1px solid var(--line);border-radius:14px}.live-result strong{font:700 25px 'Fredoka';color:var(--purple)}.graph-card{padding:12px;background:#fff;border:1px solid var(--line);border-radius:22px;box-shadow:var(--shadow)}.graph-card svg{display:block;width:100%;height:auto;background:#fcfbf7;border-radius:15px}.graph-card>p{display:flex;align-items:center;justify-content:center;gap:7px;margin:10px 0 2px;color:var(--muted);font-size:11px;flex-wrap:wrap}.legend{width:10px;height:10px;border-radius:50%}.legend.curve{background:#5b4bdb}.legend.tangent{background:#ff7062}.legend.rectangles{background:#87d9bd}.integral-grid article{display:flex;flex-direction:column;padding:21px;background:#fff;border-radius:18px}.integral-grid h3{margin:0 0 7px}.integral-grid p{color:var(--muted)}.integral-grid b{font:700 18px 'Fredoka';color:#248267;overflow-wrap:anywhere}.integral-grid small{margin-top:8px;color:var(--muted)}.area-results{display:grid;grid-template-columns:repeat(3,1fr);gap:7px;margin-top:13px}.area-results div{padding:11px 8px;background:#fff;border:1px solid var(--line);border-radius:12px;text-align:center}.area-results span{display:block;color:var(--muted);font-size:10px}.area-results strong{font:700 16px 'Fredoka';color:var(--purple)}
.practice-grid article{position:relative;padding:23px;background:#fff;border:1px solid var(--line);border-radius:19px}.practice-grid article>span{display:grid;place-items:center;width:34px;height:34px;background:#eeebff;color:var(--purple);border-radius:10px;font-weight:800}.practice-grid h3{margin:13px 0 7px}.practice-grid p{color:var(--muted)}.practice-grid b{color:var(--purple)}.mistakes{margin-top:18px;padding:22px;background:#fff4c9;border-radius:19px}.mistakes h3{margin-top:0}.mistakes li{margin:8px 0;color:#63541c}.quiz-section{background:#262144;color:#fff}.quiz-grid{display:grid;gap:13px}.quiz-grid fieldset{display:grid;gap:7px;margin:0;padding:18px;background:#ffffff0f;border:1px solid #ffffff2a;border-radius:16px}.quiz-grid legend{padding:0 6px;font-weight:800}.quiz-grid label{padding:10px;background:#ffffff0e;border-radius:9px;cursor:pointer}.quiz-grid label.correct{background:#278267}.quiz-grid label.wrong{background:#9d4038}.quiz-grid .button{justify-self:start;border:0}.quiz-result{margin:0;font-weight:800;color:#fff1ad}.next-section{display:grid;gap:24px;padding-top:70px;padding-bottom:70px}.tool-links{display:grid;gap:10px}.tool-links a{display:grid;grid-template-columns:45px 1fr;gap:1px 12px;padding:15px;background:#fff;border:1px solid var(--line);border-radius:16px;color:var(--ink);text-decoration:none}.tool-links span{grid-row:1/3;display:grid;place-items:center;background:#eeebff;border-radius:12px;font-size:20px}.tool-links b{align-self:end}.tool-links small{color:var(--purple)}
@media(min-width:760px){.calc-hero{grid-template-columns:1fr 1fr;gap:44px;padding:70px 0}.lesson-nav{grid-template-columns:repeat(5,1fr)}.section{padding:92px 0}.idea-grid{grid-template-columns:1fr 1fr}.foundation-grid,.rules-grid{grid-template-columns:repeat(4,1fr)}.split-heading,.explain-grid{grid-template-columns:1fr 1fr;align-items:center;gap:50px}.integral-grid,.practice-grid{grid-template-columns:repeat(3,1fr)}.lab-section{grid-template-columns:.75fr 1.25fr;gap:50px}.lab-section.reverse{grid-template-columns:1.25fr .75fr}.lab-section.reverse .lab-copy{order:2}.quiz-grid{grid-template-columns:1fr 1fr}.quiz-grid .button,.quiz-result{grid-column:1/-1}.next-section{grid-template-columns:1fr 1fr;align-items:center;gap:55px}}
@media print{.nav,.lesson-nav,.hero-actions,.hero-facts,.quiz-section,footer{display:none!important}.section,.calc-hero,.next-section{padding:24px 0;break-inside:avoid}.purple-section{background:#fff;color:#111}.section-heading.light>p:last-child,.rules-grid p{color:#555}.rules-grid article{border-color:#ccc}.graph-card{box-shadow:none}}