:root{--bg:#F4F7FA;--paper:#fff;--pale:#EAF1F6;--aqua:#E9F8F8;--navy:#102E46;--deep:#163C57;--teal:#13B8C5;--active:#237BD3;--heading:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;--container:1200px;--gutter:28px}
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@media(max-width:1200px){:root{--gutter:22px}.section{margin-block:49px}}
@media(max-width:920px){.brand-layout{min-height:62px;display:grid;grid-template-columns:40px minmax(0,1fr) auto;gap:10px}.menu-toggle{display:flex;align-items:center;justify-content:center;flex-direction:column;gap:5px;width:40px;height:40px;border:1px solid var(--line);border-radius:9px;background:white;cursor:pointer}.menu-toggle span{width:19px;height:2px;background:var(--navy);border-radius:2px}.brand{justify-self:center;min-width:0}.brand img{max-height:30px;max-width:min(35vw,190px)}.brand-fallback{font-size:17px}.brand-description,.desktop-nav{display:none}.registration-link{margin:0;min-height:39px;padding:6px 10px;font-size:13px}.drawer-overlay{display:block;position:fixed;inset:0;z-index:80;background:rgba(5,25,40,.6);opacity:0;visibility:hidden;pointer-events:none;transition:opacity .2s,visibility .2s}.mobile-drawer{display:block;position:fixed;top:0;bottom:0;left:0;width:min(86vw,340px);z-index:81;background:white;overflow-y:auto;transform:translateX(-102%);visibility:hidden;transition:transform .25s,visibility .25s;padding:20px 24px;box-shadow:6px 0 18px #0002}.drawer-open .drawer-overlay{opacity:1;visibility:visible;pointer-events:auto}.drawer-open .mobile-drawer{visibility:visible;transform:translateX(0)}.drawer-head{display:flex;align-items:center;justify-content:space-between;font-size:13px;font-weight:800;color:var(--heading);border-bottom:1px solid var(--line);padding-bottom:15px}.drawer-head button{width:42px;height:42px;font-size:30px;background:#edf3f6;color:var(--navy);border:0;border-radius:8px;cursor:pointer}.drawer-group{margin:19px 0 4px;font-size:12px;color:var(--muted);font-weight:800;letter-spacing:.12em}.mobile-drawer a{display:block;text-decoration:none;color:var(--heading);padding:9px 12px;border-radius:8px}.mobile-drawer a[aria-current="page"]{background:var(--aqua);font-weight:800;border-left:3px solid var(--teal)}.nojs-navigation{display:block;background:#eaf1f6}.nojs-navigation .container{display:flex;flex-wrap:wrap;gap:5px 15px;padding-block:12px}.nojs-navigation a{font-size:13px}.mobile-quick{display:flex;justify-content:center;gap:15px;flex-wrap:wrap;padding-block:21px}.mobile-quick a{font-size:13px}.home-hero{gap:25px}.content-shell{grid-template-columns:minmax(0,1fr) 200px;gap:25px}}
@media(max-width:760px){.home-hero,.split-story,.split-story--reverse,.editor-grid,.content-shell,.rules-layout,.service-layout,.gallery-section,.reading-columns{grid-template-columns:minmax(0,1fr)}.split-story--reverse .media-frame{order:0}.fact-index{margin-top:0}.screen-band{grid-template-columns:repeat(2,minmax(0,1fr))}.screen-band>.media-frame{grid-column:1/-1}.lesson-stack{grid-template-columns:minmax(0,1fr)}.lesson-stack article:nth-child(n){transform:none}.matrix{grid-template-columns:repeat(2,minmax(0,1fr))}.route-steps{grid-template-columns:repeat(2,minmax(0,1fr))}.rules-toc{position:static}.service-main{order:0}.service-sidebar{order:1}.gallery-section article:nth-child(even),.reading-columns article:nth-child(2){margin-top:0}.related-grid{grid-template-columns:1fr}.page-intro h1{font-size:31px}.media-frame--hero{--media-limit:250px}}
@media(max-width:640px){:root{--gutter:16px}body{font-size:15px;line-height:1.77}h1{font-size:29px}h2{font-size:22px}h3{font-size:18px}.page-intro h1{font-size:27px}.section{margin-block:36px}.section--soft,.section--white{padding-block:30px}.home-hero{padding-block:35px 16px;gap:20px}.home-hero h1{margin-bottom:18px}.section-intro,.lead{font-size:15.5px}.topic-directory,.two-col,.screen-band,.matrix{grid-template-columns:minmax(0,1fr)}.feature-story{padding:23px}.feature-story h3{font-size:22px}.minor-stories article{padding:20px}.route-steps article{padding:13px}.media-frame--hero{--media-limit:205px}.media-frame--feature{--media-limit:185px}.media-frame--card{--media-limit:145px}.media-frame--wide{--media-limit:135px}.media-frame--mobile{--media-limit:285px;max-width:250px}.media-frame--hero.media-missing{min-height:140px}.page-intro{padding-block:24px}.diagram-line{grid-template-columns:repeat(2,minmax(0,1fr))}.wide-chapter{margin-block:30px}.ordered-cards article{padding:18px 17px 18px 58px}.ordered-cards article::before{left:16px;top:19px}.footer-top{grid-template-columns:1fr;gap:18px}.footer-nav{grid-template-columns:repeat(2,minmax(0,1fr))}.site-footer{padding-top:30px}.anchor-nav a{padding:6px 12px}.section-heading{margin-bottom:17px}}
@media(max-width:380px){.brand-fallback{font-size:14px}.registration-link{font-size:12px;padding:5px 7px}.brand-layout{gap:6px}.route-steps{grid-template-columns:minmax(0,1fr)}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;animation-duration:.01ms!important;transition-duration:.01ms!important}}