@font-face{font-family:examFont;src:url(../media/InterVariable-s.p.2v4uvb3i5caxn.woff2)format("woff2");font-display:swap;font-weight:100 900;font-style:normal}@font-face{font-family:examFont Fallback;src:local(Arial);ascent-override:89.79%;descent-override:22.36%;line-gap-override:0.0%;size-adjust:107.89%}.examfont_9afd6d6c-module__-WPodq__className{font-family:examFont,examFont Fallback;font-style:normal}.examfont_9afd6d6c-module__-WPodq__variable{--font-hepnot-inter:"examFont", "examFont Fallback"}
.hn-site{--hn-primary:#3456c8;--hn-primary-hover:#2844a6;--hn-ink:#202b45;--hn-muted:#58647a;--hn-paper:#faf9f6;--hn-surface:#fff;--hn-soft:#edf1ff;--hn-line:#dce1ec;--hn-accent:#a44b20;color:var(--hn-ink);background:var(--hn-paper);font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;min-height:100vh;font-size:15px;line-height:1.65}.hn-site *{box-sizing:border-box}.hn-site h1,.hn-site h2,.hn-site h3{letter-spacing:-.025em;line-height:1.16}.hn-site p{line-height:1.8}.hn-wrap{max-width:1240px;margin:0 auto;padding:0 40px}.hn-site a,.hn-site button{transition:background .18s,color .18s,transform .18s}.hn-site a:focus-visible,.hn-site button:focus-visible,.hn-site input:focus-visible,.hn-site summary:focus-visible{outline:3px solid var(--hn-accent);outline-offset:5px}.hn-header{border-bottom:1px solid var(--hn-line);background:var(--hn-paper)}.hn-nav{justify-content:space-between;align-items:center;gap:25px;height:88px;display:flex}.hn-brand{letter-spacing:-2px;align-items:center;gap:9px;font-size:33px;font-weight:800;line-height:1;display:inline-flex}.hn-mark{background:var(--hn-primary);color:#fff;border-radius:11px;place-items:center;width:35px;height:35px;display:grid}.hn-brand-dot{color:var(--hn-accent);margin-left:-8px}.hn-nav nav{gap:30px;font-size:13px;font-weight:600;display:flex}.hn-nav nav a{align-items:center;gap:5px;display:flex}.hn-button{background:var(--hn-primary);border-radius:8px;justify-content:center;align-items:center;gap:14px;min-height:48px;padding:15px 23px;font-size:14px;font-weight:600;line-height:1.4;text-decoration:none;display:inline-flex;color:#fff!important}.hn-button:hover{background:var(--hn-primary-hover);transform:translateY(-1px)}.hn-button-small{min-height:43px;padding:12px 17px;font-size:12px}.hn-text-link{align-items:center;gap:9px;min-height:44px;font-size:13px;font-weight:600;display:inline-flex}.hn-hero{grid-template-columns:1.1fr 1fr;align-items:center;gap:55px;padding-top:78px;padding-bottom:70px;display:grid}.hn-eyebrow{letter-spacing:1.8px;align-items:center;gap:8px;font-size:12px;font-weight:700;display:inline-flex}.hn-eyebrow>span{background:var(--hn-accent);border-radius:50%;width:6px;height:6px}.hn-hero h1{margin:25px 0 23px;font-size:64px;font-weight:650;line-height:1.1}.hn-site em{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;color:var(--hn-accent);font-weight:400}.hn-hero-copy>p{color:var(--hn-muted);max-width:445px;font-size:15px}.hn-hero-actions{align-items:center;gap:26px;margin-top:29px;display:flex}.hn-hero-notes{color:var(--hn-muted);gap:20px;margin-top:24px;font-size:12px;display:flex}.hn-hero-notes span{align-items:center;gap:6px;display:flex}.hn-hero-art{min-width:0;padding:45px 14px 30px;position:relative}.hn-art-grid{background-image:radial-gradient(var(--hn-muted) 1px, transparent 1px);opacity:.65;background-size:19px 19px;border-radius:50%;position:absolute;inset:0}.hn-notebook{background:var(--hn-surface);border:1px solid var(--hn-line);box-shadow:12px 18px 0 var(--hn-soft), 0 25px 50px #26382b0b;background-image:linear-gradient(transparent 35px, var(--hn-line) 36px);background-size:100% 36px;border-radius:12px;padding:27px 31px 23px;position:relative;transform:rotate(-3deg)}.hn-notebook-top{letter-spacing:1.5px;color:var(--hn-muted);justify-content:space-between;font-size:12px;display:flex}.hn-notebook-title{letter-spacing:-1px;margin:27px 0 24px;font-size:30px;font-weight:600;line-height:1.18}.hn-notebook-title em{font-size:31px}.hn-equation{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;letter-spacing:1px;font-size:39px}.hn-hand-note{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;color:var(--hn-accent);margin:14px 0 8px;font-size:14px;font-style:italic}.hn-hand-note span{margin-left:12px;font-size:25px}.hn-equation-step{align-items:center;gap:19px;font-size:31px;display:flex}.hn-equation-step>span{color:var(--hn-muted);font-size:22px}.hn-equation-step strong{background:var(--hn-soft);border-radius:7px;padding:0 13px;font-weight:400}.hn-notebook-bottom{align-items:center;gap:8px;margin-top:26px;font-size:12px;display:flex}.hn-float-label{border:1px solid var(--hn-line);z-index:1;background:#fff;border-radius:9px;align-items:center;gap:10px;padding:9px 16px;font-size:12px;display:flex;position:absolute;top:11px;right:-3px;transform:rotate(4deg);box-shadow:0 7px 15px #203d3509}.hn-float-label .hn-icon{border-radius:8px;width:30px;height:30px}.hn-art-caption{text-align:center;font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;color:var(--hn-muted);margin-top:34px;font-size:13px;font-style:italic;position:relative}.hn-art-caption span{color:var(--hn-accent);margin-right:9px;font-size:21px}.hn-values{border-top:1px solid var(--hn-line);border-bottom:1px solid var(--hn-line);background:var(--hn-soft)}.hn-values>.hn-wrap{justify-content:space-between;gap:20px;padding-top:20px;padding-bottom:20px;display:flex}.hn-values span{align-items:center;gap:10px;font-size:12px;font-weight:600;display:flex}.hn-ad-wrap{padding-top:35px;padding-bottom:15px}.hn-ad{border:1px dashed var(--hn-line);background:var(--hn-soft);min-height:114px;color:var(--hn-muted);text-align:center;border-radius:8px;flex-direction:column;justify-content:space-between;gap:8px;padding:10px 20px;display:flex}.hn-ad>span{letter-spacing:2px;font-size:12px}.hn-ad>div{justify-content:center;align-items:center;gap:15px;display:flex}.hn-ad-symbol{color:var(--hn-muted);font-size:32px}.hn-ad p{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;color:var(--hn-muted);text-align:left;font-size:17px;line-height:1.3}.hn-ad p small{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;color:var(--hn-muted);margin-top:4px;font-size:12px;display:block}.hn-ad>small{color:var(--hn-muted);font-size:12px}.hn-subjects{padding-top:57px;padding-bottom:67px;scroll-margin-top:20px}.hn-section-heading{justify-content:space-between;align-items:flex-end;gap:20px;margin-bottom:27px;display:flex}.hn-section-heading h2{margin-top:13px;font-size:33px}.hn-section-heading p{color:var(--hn-muted);margin-top:12px;font-size:13px}.hn-outline-tag{border:1px solid var(--hn-line);white-space:nowrap;border-radius:30px;padding:5px 13px;font-size:12px}.hn-filter-row{justify-content:space-between;align-items:center;gap:20px;margin-bottom:24px;display:flex}.hn-tabs{background:var(--hn-soft);border-radius:9px;gap:3px;padding:4px;display:flex}.hn-tabs button{border-radius:6px;min-height:44px;padding:10px 17px;font-size:12px;font-weight:700}.hn-tabs button span{color:var(--hn-muted);margin-left:8px;font-size:12px;font-weight:400}.hn-tabs button.active{background:#fff;box-shadow:0 1px 4px #00000009}.hn-search{border:1px solid var(--hn-line);width:240px;color:var(--hn-muted);background:#fff;border-radius:8px;align-items:center;gap:10px;padding:0 13px;display:flex}.hn-search input{width:100%;min-width:0;color:var(--hn-ink);outline-offset:0;background:0 0;border:0;padding:12px 0;font-size:12px}.hn-course-grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:15px;display:grid}.hn-course{border:1px solid var(--hn-line);background:var(--hn-surface);border-radius:10px;min-width:0;padding:22px}.hn-course-top{justify-content:space-between;align-items:center;margin-bottom:19px;display:flex}.hn-icon{border-radius:12px;justify-content:center;align-items:center;width:46px;height:46px;display:inline-flex}.mint{color:#517145;background:#e8efdf}.peach{color:#b66a48;background:#fae9df}.lavender{color:#8370a3;background:#eee8f7}.yellow{color:#ac8a39;background:#f7efd7}.blue{color:#58839b;background:#e4edf3}.hn-course-level{color:var(--hn-muted);border:1px solid var(--hn-line);border-radius:5px;padding:2px 6px;font-size:12px}.hn-course h3{letter-spacing:-.5px;font-size:19px;font-weight:650}.hn-course p{color:var(--hn-muted);min-height:39px;margin-top:9px;font-size:12px}.hn-course>a{border-top:1px solid var(--hn-line);color:var(--hn-primary);justify-content:space-between;align-items:center;min-height:40px;margin-top:18px;padding-top:13px;font-size:12px;font-weight:650;display:flex}.hn-coming{border-top:1px solid var(--hn-line);color:var(--hn-muted);margin-top:18px;padding-top:13px;font-size:12px;display:block}.hn-catalog-note{color:var(--hn-muted);margin-top:17px;font-size:12px}.hn-empty{padding:20px}.hn-how{border-top:1px solid var(--hn-line);padding-top:43px;padding-bottom:60px}.hn-steps{grid-template-columns:repeat(3,1fr);gap:35px;margin-top:35px;display:grid}.hn-steps article>span{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;color:var(--hn-accent);font-size:27px;font-style:italic}.hn-steps h3{letter-spacing:-.5px;margin:13px 0 10px;font-size:18px}.hn-steps p{color:var(--hn-muted);max-width:290px;font-size:12px}.hn-mission{background:var(--hn-soft);border-radius:14px;align-items:center;gap:65px;width:calc(100% - 80px);max-width:1160px;margin-bottom:60px;padding:46px 65px;display:flex}.hn-mission-star{color:var(--hn-muted);font-size:135px;line-height:1}.hn-mission h2{margin:12px 0 15px;font-size:33px}.hn-mission p{max-width:650px;color:var(--hn-muted);font-size:13px}.hn-mission details{margin-top:15px;font-size:12px}.hn-site summary{cursor:pointer;align-content:center;min-height:44px;font-weight:600}.hn-footer{border-top:1px solid var(--hn-line);flex-wrap:wrap;justify-content:space-between;align-items:center;gap:28px;padding-top:34px;padding-bottom:35px;display:flex}.hn-footer .hn-brand{font-size:27px}.hn-footer p{color:var(--hn-muted);margin-top:9px;font-size:12px}.hn-footer>div:nth-child(2){align-items:center;gap:23px;font-size:12px;display:flex}.hn-footer a{align-items:center;gap:4px;min-height:32px;display:inline-flex}.hn-footer>small{width:100%;color:var(--hn-muted);border-top:1px solid var(--hn-line);justify-content:space-between;align-items:center;padding-top:17px;font-size:12px;display:flex}.hn-skip{z-index:100;background:#fff;padding:12px;position:fixed;top:-100px;left:12px}.hn-skip:focus{top:10px}.hn-breadcrumb{color:var(--hn-muted);flex-wrap:wrap;align-items:center;gap:12px;padding-top:26px;padding-bottom:32px;font-size:12px;display:flex}.hn-lesson-layout{grid-template-columns:185px minmax(0,650px) 205px;align-items:start;gap:30px;padding-bottom:75px;display:grid}.hn-toc{font-size:12px;position:sticky;top:25px}.hn-back{align-items:center;gap:7px;margin-bottom:33px;font-size:12px;display:flex}.hn-toc>.hn-eyebrow{font-size:12px}.hn-toc nav{border-left:1px solid var(--hn-line);flex-direction:column;margin-top:17px;display:flex}.hn-toc nav a{gap:11px;min-height:44px;padding:11px 10px;font-size:12px;line-height:1.4;display:flex}.hn-toc nav a:hover{background:var(--hn-soft)}.hn-toc nav a span{color:var(--hn-muted);font-size:12px}.hn-toc-note{background:var(--hn-soft);border-radius:8px;align-items:center;gap:11px;margin-top:30px;padding:17px;font-size:12px;display:flex}.hn-lesson{min-width:0}.hn-lesson-heading h1{margin:17px 0 18px;font-size:45px}.hn-lesson-heading>p{color:var(--hn-muted);font-size:14px}.hn-lesson-meta{color:var(--hn-muted);flex-wrap:wrap;gap:16px;margin-top:21px;font-size:12px;display:flex}.hn-lesson-meta>span{align-items:center;gap:6px;display:flex}.hn-draft{color:#8a6745;background:#f7efdf;border:1px solid #ebdfc7;border-radius:6px;margin-top:20px;padding:9px 12px;font-size:12px;line-height:1.5}.hn-objectives{background:var(--hn-soft);border-radius:9px;flex-direction:column;gap:9px;margin-top:27px;padding:21px 23px;font-size:12px;display:flex}.hn-objectives strong{margin-bottom:3px;font-size:13px}.hn-objectives>span{align-items:flex-start;gap:8px;display:flex}.hn-lesson section{margin-top:43px;scroll-margin-top:24px}.hn-section-number{color:var(--hn-muted);letter-spacing:1.4px;font-size:12px;font-weight:600}.hn-lesson h2{letter-spacing:-.8px;margin:11px 0 17px;font-size:27px}.hn-lesson section>p{color:var(--hn-muted);margin-bottom:17px;font-size:14px}.hn-definition{background:var(--hn-surface);border:1px solid var(--hn-line);border-left:3px solid var(--hn-primary);border-radius:7px;margin:24px 0;padding:23px}.hn-definition>span{letter-spacing:1.5px;color:var(--hn-muted);font-size:12px;display:block}.hn-definition>strong{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;letter-spacing:1px;margin:13px 0;font-size:30px;font-weight:400;display:block}.hn-definition small{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;color:var(--hn-muted);white-space:nowrap;margin-left:18px;font-size:12px}.hn-definition p{color:var(--hn-muted);font-size:12px}.hn-method{gap:17px;margin:24px 0;padding:0;list-style:none;display:grid}.hn-method li{gap:14px;display:flex}.hn-method li>span{background:var(--hn-soft);border-radius:50%;flex-shrink:0;place-items:center;width:27px;height:27px;font-size:12px;display:grid}.hn-method strong{font-size:12px}.hn-method p{color:var(--hn-muted);margin-top:4px;font-size:12px}.hn-worked{border:1px solid var(--hn-line);background:var(--hn-surface);border-radius:10px;overflow:hidden}.hn-worked-question{background:var(--hn-soft);flex-wrap:wrap;align-items:center;gap:16px;padding:23px;display:flex}.hn-worked-question>span{letter-spacing:1px;font-size:12px}.hn-worked-question strong{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;font-size:26px;font-weight:400}.hn-worked-question p{margin-left:auto;font-size:12px}.hn-worked-step{border-bottom:1px solid var(--hn-line);gap:17px;padding:22px;display:flex}.hn-worked-step>span{color:var(--hn-muted);font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;font-size:18px}.hn-worked-step p{color:var(--hn-muted);font-size:12px}.hn-worked-step strong{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;font-size:23px;font-weight:400;line-height:1.8;display:block}.hn-worked-check{background:var(--hn-soft);align-items:center;gap:10px;padding:17px 22px;font-size:12px;display:flex}.hn-lesson>.hn-ad{margin-top:35px}.hn-warning{color:#846045;background:#faf0e4;border:1px solid #efdfcc;border-radius:8px;gap:15px;padding:21px;display:flex}.hn-warning p{font-size:13px}.hn-warning svg{margin-top:4px}.hn-practice{border:1px solid var(--hn-line);background:var(--hn-surface);border-radius:11px;padding:25px}.hn-practice>p>strong{font-family:var(--font-hepnot-inter), "Segoe UI", Arial, sans-serif;letter-spacing:1px;font-size:23px}.hn-practice fieldset{border:0;flex-wrap:wrap;gap:8px;margin:20px 0;padding:0;display:flex}.hn-practice fieldset label{border:1px solid var(--hn-line);cursor:pointer;border-radius:7px;flex:1;align-items:center;gap:8px;min-width:63px;min-height:49px;padding:10px;font-size:14px;display:flex}.hn-practice fieldset label span{color:var(--hn-muted);font-size:12px}.hn-practice input{accent-color:var(--hn-primary);width:15px;height:15px;margin:0}.hn-practice fieldset label.selected{border-color:var(--hn-primary);background:var(--hn-soft)}.hn-practice fieldset label.correct{background:#e5f0dc;border-color:#3a7441}.hn-practice-actions{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:13px;display:flex}.hn-practice-actions .hn-button{padding:12px 15px;font-size:12px}.hn-hint{background:#faf2e2;border-radius:6px;padding:12px;margin:15px 0 0!important;font-size:12px!important}.hn-feedback{background:#eef4e7;border-radius:8px;margin-top:17px;padding:16px;font-size:13px}.hn-feedback p{margin:7px 0;font-size:12px}.hn-summary{color:var(--hn-muted);padding-left:20px;font-size:13px;line-height:2.2}.hn-source{border-top:1px solid var(--hn-line);margin:25px 0;padding-top:10px;font-size:12px}.hn-source p{color:var(--hn-muted);margin:10px 0}.hn-source a{text-decoration:underline}.hn-next{background:var(--hn-soft);border-radius:8px;flex-direction:column;gap:10px;padding:20px;font-size:14px;display:flex}.hn-next span{align-items:center;gap:10px;font-size:12px;font-weight:600;display:flex}.hn-side-card{background:var(--hn-soft);border-radius:9px;padding:24px 20px}.hn-side-card .hn-eyebrow{letter-spacing:1px;font-size:12px}.hn-side-card h3{margin:19px 0;font-size:29px}.hn-side-card p{color:var(--hn-muted);font-size:12px}.hn-side-card .hn-button{gap:8px;width:100%;margin-top:20px;padding:12px;font-size:12px}.hn-ad-side{min-height:285px;margin-top:20px;padding:16px}.hn-ad-side>div{flex-direction:column;gap:15px}.hn-ad-side p{text-align:center;font-size:20px}.hn-ad-side p small{margin-top:15px;font-size:12px;line-height:1.7}.hn-sr{clip:rect(0, 0, 0, 0);width:1px;height:1px;position:absolute;overflow:hidden}@media (min-width:1450px){.hn-wrap{max-width:1320px}.hn-hero{gap:90px}.hn-hero h1{font-size:71px}.hn-lesson-layout{grid-template-columns:190px minmax(0,700px) 220px;gap:35px}}@media (max-width:1050px){.hn-wrap{padding-left:28px;padding-right:28px}.hn-hero{gap:25px}.hn-hero h1{font-size:51px}.hn-notebook{padding:24px}.hn-notebook-title{font-size:27px}.hn-equation{font-size:33px}.hn-course-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.hn-lesson-layout{grid-template-columns:155px minmax(0,1fr);gap:27px}.hn-lesson-side{display:none}.hn-mission{width:calc(100% - 56px);padding:35px}.hn-mission-star{font-size:100px}.hn-nav nav{gap:18px}.hn-hero-notes{gap:12px}}@media (max-width:760px){.hn-wrap{padding-left:21px;padding-right:21px}.hn-nav{gap:10px;height:73px}.hn-brand{font-size:28px}.hn-mark{width:30px;height:30px}.hn-nav nav{display:none}.hn-button-small{gap:7px;padding:11px 12px;font-size:12px}.hn-hero{grid-template-columns:1fr;gap:25px;padding-top:44px;padding-bottom:35px}.hn-hero h1{margin:21px 0;font-size:48px}.hn-hero-copy>p{max-width:520px;font-size:14px}.hn-eyebrow{letter-spacing:1.3px;font-size:12px}.hn-hero-actions{gap:22px;margin-top:24px}.hn-hero-notes{flex-wrap:wrap;gap:15px;font-size:12px}.hn-hero-art{width:100%;max-width:430px;margin:0 auto;padding:40px 17px 25px}.hn-notebook{padding:23px 26px}.hn-notebook-title{font-size:30px}.hn-equation{font-size:36px}.hn-float-label{top:10px;right:4px}.hn-values>.hn-wrap{grid-template-columns:1fr 1fr;gap:17px 12px;padding-top:20px;padding-bottom:20px;display:grid}.hn-values span{gap:7px;font-size:12px}.hn-values svg{width:16px}.hn-ad-wrap{padding-top:25px;padding-bottom:0}.hn-ad{min-height:122px;padding:10px 14px}.hn-ad p{font-size:15px}.hn-ad p small{max-width:235px;font-size:12px;line-height:1.5}.hn-subjects{padding-top:38px;padding-bottom:40px}.hn-section-heading{align-items:flex-start;gap:10px;margin-bottom:23px}.hn-section-heading h2{margin-top:12px;font-size:29px}.hn-section-heading p{font-size:12px}.hn-outline-tag{display:none}.hn-filter-row{flex-direction:column;align-items:stretch;gap:15px}.hn-tabs{align-self:flex-start}.hn-tabs button{padding:10px 14px}.hn-tabs button span{margin-left:5px;font-size:12px}.hn-search{width:100%}.hn-course-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:11px}.hn-course{padding:16px 14px}.hn-course-top{margin-bottom:16px}.hn-icon{border-radius:10px;width:40px;height:40px}.hn-icon svg{width:22px}.hn-course h3{font-size:18px}.hn-course p{min-height:38px;font-size:12px;line-height:1.7}.hn-course>a,.hn-coming{margin-top:14px;font-size:12px}.hn-course>a{gap:3px}.hn-catalog-note{font-size:12px}.hn-how{padding-top:30px;padding-bottom:35px}.hn-how .hn-section-heading{flex-direction:column;gap:8px}.hn-how .hn-section-heading>p br{display:none}.hn-steps{grid-template-columns:1fr;gap:21px;margin-top:20px}.hn-steps article{grid-template-columns:40px 1fr;gap:4px 15px;display:grid}.hn-steps article>span{grid-row:span 2}.hn-steps h3{margin:5px 0;font-size:17px}.hn-steps p{max-width:100%;font-size:12px}.hn-mission{align-items:flex-start;gap:15px;width:calc(100% - 42px);margin-bottom:35px;padding:28px}.hn-mission-star{display:none}.hn-mission h2{font-size:29px}.hn-mission p{font-size:12px}.hn-footer{gap:22px;padding-top:25px;padding-bottom:23px}.hn-footer>div:nth-child(2){flex-wrap:wrap;gap:10px 20px;font-size:12px}.hn-footer>small{font-size:12px}.hn-breadcrumb{gap:8px;padding-top:20px;padding-bottom:24px}.hn-lesson-layout{flex-direction:column;gap:22px;padding-bottom:40px;display:flex}.hn-toc{width:100%;position:static}.hn-back,.hn-toc>.hn-eyebrow,.hn-toc-note{display:none}.hn-toc nav{border:1px solid var(--hn-line);scrollbar-width:thin;background:var(--hn-soft);border-radius:8px;flex-direction:row;margin:0;padding:3px;overflow-x:auto}.hn-toc nav a{white-space:nowrap;gap:7px;min-height:44px;padding:12px;font-size:12px}.hn-lesson-heading h1{margin:15px 0;font-size:39px}.hn-lesson-heading>p{font-size:13px}.hn-lesson-meta{gap:10px;font-size:12px}.hn-objectives{padding:18px;font-size:12px}.hn-lesson section{margin-top:34px}.hn-lesson h2{font-size:25px}.hn-lesson section>p{font-size:13px}.hn-definition{padding:19px}.hn-definition>strong{font-size:27px}.hn-worked-question{gap:12px;padding:18px}.hn-worked-question strong{font-size:24px}.hn-worked-step{gap:13px;padding:18px 15px}.hn-worked-step strong{font-size:21px}.hn-worked-check{padding:16px;font-size:12px}.hn-warning{gap:10px;padding:17px}.hn-warning p{font-size:12px}.hn-practice{padding:20px 16px}.hn-practice fieldset{gap:6px}.hn-practice fieldset label{gap:5px;min-width:49px;padding:9px 6px;font-size:13px}.hn-practice fieldset label span{display:none}.hn-practice fieldset input{width:13px;height:13px}.hn-practice-actions{gap:8px}.hn-practice-actions .hn-button{padding:12px;font-size:12px}.hn-practice-actions .hn-text-link,.hn-source{font-size:12px}}@media (prefers-reduced-motion:reduce){.hn-site *{scroll-behavior:auto!important;transition:none!important}}.hn-toc-caption{justify-content:space-between;align-items:center;gap:8px;font-size:12px;font-weight:650;display:flex}.hn-toc-caption small{color:var(--hn-muted);font-size:12px;font-weight:400}.hn-toc-mobile-hint{display:none}@media (max-width:760px){.hn-toc{z-index:20;background:var(--hn-paper);border-bottom:1px solid var(--hn-line);align-self:flex-start;padding:10px 0;position:sticky;top:0}.hn-toc-caption{font-size:13px}.hn-toc-mobile-hint{color:var(--hn-muted);margin:2px 0 8px;font-size:12px;display:block}.hn-toc nav a{padding:12px 14px;font-size:12px}.hn-lesson section,.hn-lesson [id]{scroll-margin-top:140px}}.hn-ad-banner{width:100%;min-width:0;min-height:128px}.hn-ad-rail{min-width:0;min-height:285px}.hn-ad-side{margin-top:48px}.hn-lesson>.hn-ad{margin-top:48px;margin-bottom:48px}.hn-ad-wrap.hn-ad-bottom{padding-bottom:42px}@media (max-width:760px){.hn-ad-banner{min-height:136px}.hn-lesson>.hn-ad{margin-top:40px;margin-bottom:40px}.hn-ad-rail{display:none}}.hn-ad-mobile-only{display:none}.hn-equation-visual{border:1px solid var(--hn-line);background:var(--hn-soft);border-radius:14px;margin:28px 0;padding:24px}.hn-equation-visual svg{width:100%;max-width:600px;height:auto;margin:20px auto;display:block}.hn-equation-visual figcaption{font-size:14px;line-height:1.8}.hn-equation-visual figcaption p{margin:8px 0}.hn-equation-visual figcaption small{color:var(--hn-muted);font-size:12px;display:block}.hn-inverse-visual svg{max-width:330px}@media (max-width:760px){.hn-ad[data-ad-placement=lesson-intro]{display:none}.hn-ad-mobile-only{display:flex}.hn-equation-visual{margin:24px 0;padding:16px 12px}.hn-equation-visual figcaption{font-size:14px}}.hn-brand-icon{flex:none;width:35px;height:35px;display:block}.hn-footer .hn-brand-icon{width:30px;height:30px}@media (max-width:760px){.hn-brand-icon{width:30px;height:30px}}.hn-site{font-optical-sizing:auto;font-size:16px}.hn-brand{letter-spacing:-.045em}.hn-site em{font-style:normal;font-weight:650}.hn-hero-copy>p{max-width:52ch;font-size:18px}.hn-hero h1{font-weight:750}.hn-notebook{box-shadow:12px 18px #e4e9fa,0 25px 50px #202b450b}.hn-notebook-top{letter-spacing:.06em}.hn-notebook-title em{color:var(--hn-primary)}.hn-equation,.hn-result,.hn-worked-step strong{font-variant-numeric:tabular-nums}.hn-lesson-heading>p{font-size:18px}.hn-lesson section>p,.hn-definition>p,.hn-variant p,.hn-variant li{font-size:18px;line-height:1.75}.hn-method strong,.hn-method p,.hn-worked-step p,.hn-worked-check,.hn-warning p,.hn-summary,.hn-equation-visual figcaption,.hn-review-card p,.hn-review-answer,.hn-feedback,.hn-feedback p{font-size:16px;line-height:1.75}.hn-objectives{font-size:14px;line-height:1.7}.hn-definition p{margin-bottom:0}.hn-lesson .hn-lab>p,.hn-review-page>p{font-size:16px!important}.hn-error-hunt label,.hn-geometry-control,.hn-practice fieldset label{font-size:15px}.hn-choice-row button,.hn-ratings button{font-size:13px}.hn-equation-visual svg text{font-family:inherit}.hn-method-compare,.hn-course p,.hn-steps p,.hn-mission p{font-size:14px}.hn-course>a{color:var(--hn-primary)}.hn-notebook-bottom,.hn-notebook-top,.hn-toc nav a span,.hn-section-number,.hn-ad-symbol{color:var(--hn-muted)}@media (max-width:760px){.hn-hero h1{font-size:44px}.hn-lesson-heading h1{overflow-wrap:break-word;font-size:36px}.hn-hero-copy>p,.hn-lesson section>p,.hn-variant p,.hn-variant li{font-size:18px}.hn-choice-row button{font-size:12px}.hn-practice fieldset label{min-width:44px}.hn-method-compare th,.hn-method-compare td{font-size:12px}}.hn-site .hn-variant p,.hn-site .hn-variant li{font-size:18px;line-height:1.75}.hn-site .hn-review-card p,.hn-site .hn-review-answer{font-size:16px;line-height:1.75}.hn-site .hn-choice-row button,.hn-site .hn-ratings button{font-size:13px}.hn-site .hn-error-hunt label,.hn-site .hn-geometry-control{font-size:15px}.hn-site .hn-method-compare{font-size:14px}.hn-lesson-heading h1{font-weight:700}.hn-hero h1 em,.hn-lesson-heading h1 em{color:var(--hn-primary)}@media (max-width:760px){.hn-site .hn-choice-row button,.hn-site .hn-method-compare th,.hn-site .hn-method-compare td{font-size:12px}}.hn-nav-actions{flex-shrink:0;align-items:center;gap:18px;display:flex}.hn-account-link{white-space:nowrap;align-items:center;min-height:44px;font-size:13px;font-weight:650;display:inline-flex}.hn-nav-action-short{display:none}@media (max-width:1050px){.hn-nav nav a:last-child{display:none}}@media (max-width:760px){.hn-nav-actions{gap:12px}.hn-account-link{font-size:12px}.hn-nav-action-full{display:none}.hn-nav-action-short{display:inline}.hn-header .hn-button-small{gap:5px;padding:10px 11px}}.hn-legal{max-width:760px;padding-top:48px;padding-bottom:64px;line-height:1.75}.hn-legal h1{margin:10px 0 18px}.hn-legal h2{margin:36px 0 10px;font-size:1.25rem}.hn-legal ul{padding-left:22px}.hn-legal li{margin-bottom:8px}.hn-legal a{color:var(--hn-green);overflow-wrap:anywhere}.hn-menu{display:none;position:relative}.hn-menu summary{border:1px solid var(--hn-line);cursor:pointer;background:var(--hn-surface);border-radius:8px;place-items:center;width:44px;height:44px;list-style:none;display:grid}.hn-menu summary::-webkit-details-marker{display:none}.hn-menu-panel{z-index:30;background:var(--hn-surface);border:1px solid var(--hn-line);border-radius:10px;min-width:220px;padding:6px;display:grid;position:absolute;top:52px;right:0;box-shadow:0 12px 32px #202b4524}.hn-menu-panel a{border-radius:6px;align-items:center;min-height:44px;padding:0 12px;font-size:14px;font-weight:600;display:flex}.hn-menu-panel a:hover{background:var(--hn-soft)}@media (max-width:760px){.hn-menu{display:block}}.hn-ad-wrap:empty{display:none}
.lesson-downloads-module__fiYfvW__section{scroll-margin-top:24px}.lesson-downloads-module__fiYfvW__note{border-left:3px solid var(--hn-accent);color:var(--hn-ink,var(--hn-ink));background:#f6eee6;padding:12px 15px;font-size:13px}.lesson-downloads-module__fiYfvW__grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:22px;display:grid}.lesson-downloads-module__fiYfvW__card{border:1px solid var(--hn-line);min-width:0;color:inherit;background:#fff;border-radius:14px;align-items:flex-start;gap:12px;padding:21px 18px;text-decoration:none;display:flex}.lesson-downloads-module__fiYfvW__card:hover{background:var(--hn-soft);border-color:var(--hn-primary,var(--hn-primary))}.lesson-downloads-module__fiYfvW__fileIcon{color:var(--hn-primary,var(--hn-primary));flex-shrink:0;margin-top:2px}.lesson-downloads-module__fiYfvW__content{flex-direction:column;min-width:0;height:100%;display:flex}.lesson-downloads-module__fiYfvW__title{font-size:17px;line-height:1.35}.lesson-downloads-module__fiYfvW__description{color:var(--hn-muted,var(--hn-muted));margin-top:7px;font-size:14px;line-height:1.6}.lesson-downloads-module__fiYfvW__meta{color:var(--hn-muted,var(--hn-muted));margin-top:13px;font-size:12px}.lesson-downloads-module__fiYfvW__action{color:var(--hn-primary,var(--hn-primary));align-items:center;gap:7px;margin-top:9px;font-size:13px;font-weight:700;display:inline-flex}@media (max-width:600px){.lesson-downloads-module__fiYfvW__grid{grid-template-columns:minmax(0,1fr)}}
.student-login-module__hl8HRa__layout{grid-template-columns:1fr 460px;align-items:start;gap:90px;padding-top:66px;padding-bottom:70px;display:grid}.student-login-module__hl8HRa__story{min-width:0;padding-top:32px}.student-login-module__hl8HRa__story h1{margin:22px 0;font-size:48px;font-weight:750;line-height:1.12}.student-login-module__hl8HRa__story h1 em{color:var(--hn-primary)}.student-login-module__hl8HRa__story>p{color:var(--hn-muted);max-width:42ch;font-size:18px}.student-login-module__hl8HRa__notebook{border:1px solid var(--hn-line);background:repeating-linear-gradient(#fff 0 35px,#e9edf7 35px 36px);border-radius:16px;max-width:370px;margin:42px 8px 34px;padding:25px 30px;transform:rotate(-3deg);box-shadow:10px 13px #e6eafb}.student-login-module__hl8HRa__notebook>span{letter-spacing:.08em;color:var(--hn-muted);font-size:11px;display:block}.student-login-module__hl8HRa__notebook>strong{letter-spacing:.02em;margin:27px 0 11px;font-size:32px;font-weight:600;display:block}.student-login-module__hl8HRa__notebook>div{color:var(--hn-muted);font-size:14px}.student-login-module__hl8HRa__notebook>b{background:var(--hn-soft);color:var(--hn-primary);border-radius:8px;align-items:center;gap:16px;margin:18px 0;padding:5px 14px;font-size:27px;display:inline-flex}.student-login-module__hl8HRa__notebook>small{color:var(--hn-muted);font-size:12px;display:block}.student-login-module__hl8HRa__promise{align-items:center;gap:13px;margin-top:34px;font-size:14px;display:flex}.student-login-module__hl8HRa__promise>svg{color:var(--hn-primary);flex-shrink:0}.student-login-module__hl8HRa__panel{border:1px solid var(--hn-line);background:#fff;border-radius:20px;min-width:0;padding:32px;box-shadow:0 12px 36px #202b4505}.student-login-module__hl8HRa__back{color:var(--hn-muted);align-items:center;gap:8px;min-height:32px;margin-bottom:26px;font-size:13px;display:inline-flex}.student-login-module__hl8HRa__icon{background:var(--hn-soft);width:48px;height:48px;color:var(--hn-primary);border-radius:13px;place-items:center;margin-bottom:24px;display:grid}.student-login-module__hl8HRa__step{letter-spacing:.08em;color:var(--hn-muted);font-size:11px;font-weight:650;display:block}.student-login-module__hl8HRa__panel h2{margin:11px 0;font-size:30px;font-weight:700}.student-login-module__hl8HRa__panel>p{color:var(--hn-muted);overflow-wrap:anywhere;margin:0 0 22px;font-size:14px}.student-login-module__hl8HRa__panel .student-login-module__hl8HRa__notice{background:var(--hn-soft);color:var(--hn-ink);border-radius:9px;padding:13px 15px;font-size:13px}.student-login-module__hl8HRa__google,.student-login-module__hl8HRa__primary{cursor:pointer;border-radius:9px;justify-content:center;align-items:center;gap:12px;width:100%;min-height:50px;font-size:14px;font-weight:600;display:flex}.student-login-module__hl8HRa__google{background:#fff;border:1px solid #b9c3d8}.student-login-module__hl8HRa__google:hover:not(:disabled){background:#f8f9fd}.student-login-module__hl8HRa__divider{color:var(--hn-muted);align-items:center;gap:13px;margin:24px 0;font-size:12px;display:flex}.student-login-module__hl8HRa__divider:before,.student-login-module__hl8HRa__divider:after{content:"";background:var(--hn-line);flex:1;height:1px}.student-login-module__hl8HRa__panel form label{margin-bottom:8px;font-size:13px;font-weight:600;display:block}.student-login-module__hl8HRa__panel form input{width:100%;min-height:50px;color:var(--hn-ink);background:#fff;border:1px solid #aab7cf;border-radius:9px;padding:12px 14px;font-size:16px}.student-login-module__hl8HRa__primary{background:var(--hn-primary);color:#fff;border:1px solid var(--hn-primary);margin-top:16px}.student-login-module__hl8HRa__primary:hover:not(:disabled){background:var(--hn-primary-hover)}.student-login-module__hl8HRa__panel button:disabled{opacity:.55;cursor:not-allowed}.student-login-module__hl8HRa__panel .student-login-module__hl8HRa__code{letter-spacing:.42em;text-align:center;font-variant-numeric:tabular-nums;min-height:68px;font-size:29px}.student-login-module__hl8HRa__help{color:var(--hn-muted);margin:10px 0;font-size:12px;display:block}.student-login-module__hl8HRa__codeActions{flex-wrap:wrap;justify-content:space-between;gap:6px;margin-top:13px;display:flex}.student-login-module__hl8HRa__codeActions button{color:var(--hn-primary);align-items:center;gap:6px;min-height:44px;font-size:12px;display:inline-flex}.student-login-module__hl8HRa__panel .student-login-module__hl8HRa__error{color:#9c352b;margin:14px 0 0;font-size:13px}.student-login-module__hl8HRa__error:empty{display:none}.student-login-module__hl8HRa__security{color:var(--hn-muted);justify-content:center;align-items:center;gap:8px;margin:21px 0;font-size:12px;display:flex}.student-login-module__hl8HRa__guest{border-top:1px solid var(--hn-line);min-height:48px;color:var(--hn-primary);justify-content:center;align-items:center;gap:8px;padding-top:15px;font-size:14px;font-weight:600;display:flex}.student-login-module__hl8HRa__university{text-align:center;color:var(--hn-muted);min-height:40px;padding-top:12px;font-size:12px;display:block}.student-login-module__hl8HRa__previewTools{border-top:1px dashed var(--hn-line);color:var(--hn-muted);flex-wrap:wrap;justify-content:space-between;align-items:center;gap:8px;margin-top:15px;padding-top:15px;font-size:11px;display:flex}.student-login-module__hl8HRa__previewTools button{min-height:44px;color:var(--hn-primary);text-decoration:underline}@media (max-width:1050px){.student-login-module__hl8HRa__layout{grid-template-columns:1fr 420px;gap:42px}.student-login-module__hl8HRa__story h1{font-size:40px}.student-login-module__hl8HRa__notebook{padding:22px}}@media (max-width:760px){.student-login-module__hl8HRa__layout{flex-direction:column;gap:25px;padding-top:27px;padding-bottom:40px;display:flex}.student-login-module__hl8HRa__story{width:100%;padding-top:0}.student-login-module__hl8HRa__story>p{margin:12px 0;font-size:16px}.student-login-module__hl8HRa__notebook,.student-login-module__hl8HRa__promise{display:none}.student-login-module__hl8HRa__panel{border-radius:15px;width:100%;padding:23px 20px}.student-login-module__hl8HRa__back,.student-login-module__hl8HRa__icon{margin-bottom:18px}.student-login-module__hl8HRa__panel h2{font-size:27px}.student-login-module__hl8HRa__security{font-size:11px}.student-login-module__hl8HRa__story h1{margin:8px 0 0;font-size:28px}.student-login-module__hl8HRa__story>p,.student-login-module__hl8HRa__icon{display:none}.student-login-module__hl8HRa__back{margin-bottom:15px}}