.ovl-shell{--ovl-blue:#2563eb;--ovl-ink:#172033;--ovl-muted:#546174;--ovl-line:#d8e0e9;box-sizing:border-box;max-width:1240px;margin:0 auto;padding:48px 24px 76px;color:var(--ovl-ink);font-size:17px;line-height:1.75}.ovl-shell *{box-sizing:border-box}.ovl-shell [hidden]{display:none!important}.ovl-shell a{color:#1d4ed8;text-underline-offset:4px}.ovl-shell h1,.ovl-shell h2,.ovl-shell h3{color:var(--ovl-ink);line-height:1.2;letter-spacing:-.025em;overflow-wrap:anywhere}.ovl-shell h1{font-size:clamp(32px,4.2vw,54px);margin:12px 0 20px}.ovl-shell h2{font-size:clamp(24px,2.5vw,31px);margin:0 0 20px}.ovl-shell h3{font-size:20px;margin:20px 0 10px}.ovl-shell p{margin:0 0 18px}.ovl-shell li+li{margin-top:10px}.ovl-shell ul{padding-left:24px}.ovl-breadcrumb{display:flex;flex-wrap:wrap;gap:8px 12px;font-size:14px;margin-bottom:32px}.ovl-kicker,.ovl-step{font-size:12px;font-weight:700;letter-spacing:.12em;text-transform:uppercase;color:#1d4ed8}.ovl-hero{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,1fr);gap:32px;align-items:center;padding:32px;border:1px solid var(--ovl-line);border-top:3px solid #8eafe8;border-radius:18px;background:#f5f7fb;margin-bottom:40px}.ovl-hero>div{min-width:0}.ovl-hero:not(:has(.ovl-hero-art)){display:block}.ovl-intro{max-width:780px;font-size:19px}.ovl-meta{font-size:14px;color:var(--ovl-muted)}.ovl-hero-art{width:100%;height:auto;border-radius:12px}.ovl-actions{display:flex;flex-wrap:wrap;gap:12px;margin:22px 0 0}.ovl-shell .ovl-button{appearance:none;display:inline-flex;align-items:center;justify-content:center;min-height:48px;min-width:150px;max-width:100%;padding:10px 18px;border:1px solid var(--ovl-line);border-radius:10px;background:#fff;color:var(--ovl-ink);font-family:inherit;font-size:14px;font-weight:600;line-height:1.4;text-align:center;text-decoration:none;white-space:normal;overflow-wrap:anywhere;box-shadow:none;cursor:pointer;transition:background .15s,color .15s,border-color .15s}.ovl-shell .ovl-button:focus-visible{background:var(--ovl-blue);border-color:var(--ovl-blue);color:#fff;outline:3px solid #abc7fc;outline-offset:3px}.ovl-shell a:focus-visible,.ovl-shell summary:focus-visible,.ovl-shell pre:focus-visible{outline:3px solid #2563eb;outline-offset:4px}.ovl-panel{padding:28px;border:1px solid var(--ovl-line);border-top:3px solid #8eafe8;border-radius:16px;background:#fff;margin-bottom:32px;min-width:0}.ovl-panel p:last-child{margin-bottom:0}.ovl-grid{list-style:none;margin:0 0 40px;padding:0!important;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.ovl-grid li{margin:0!important;min-width:0}.ovl-card{display:flex;flex-direction:column;height:100%;padding:26px;border:1px solid var(--ovl-line);border-top:3px solid #8eafe8;border-radius:16px;background:#fff;color:var(--ovl-ink)!important;text-decoration:none}.ovl-card h3{margin:14px 0}.ovl-card p{color:var(--ovl-muted)}.ovl-card-link{margin-top:auto;font-size:14px;font-weight:700;color:#1d4ed8}.ovl-layout{display:grid;grid-template-columns:250px minmax(0,1fr);align-items:start;gap:36px}.ovl-sidebar{position:sticky;top:110px;font-size:14px;background:#f5f7fb;border-radius:14px;padding:20px;border:1px solid var(--ovl-line)}.ovl-sidebar ol{padding-left:22px;margin-bottom:0}.ovl-sidebar a{color:var(--ovl-muted);text-decoration:none}.ovl-sidebar a[aria-current]{color:#1d4ed8;font-weight:700;text-decoration:none;background:#eef4ff;border-color:#8eafe8}.ovl-shell summary{cursor:pointer;font-weight:650;min-height:44px;padding:8px 0}.ovl-article{min-width:0}.ovl-on-page{padding:0 0 28px;border-bottom:1px solid var(--ovl-line);margin-bottom:32px;font-size:15px}.ovl-terms{margin:36px 0}.ovl-terms dl{display:grid;grid-template-columns:minmax(100px,1fr) minmax(0,3fr);gap:12px 20px}.ovl-terms dt{font-weight:700}.ovl-terms dd{margin:0;color:var(--ovl-muted);min-width:0}.ovl-section{scroll-margin-top:110px;margin:44px 0;min-width:0}.ovl-note{padding:20px 24px;border-left:3px solid #2563eb;background:#eef4ff;border-radius:0 12px 12px 0;margin:24px 0}.ovl-note h3{margin-top:0}.ovl-note p:last-child{margin-bottom:0}.ovl-code{margin:24px 0;max-width:100%;min-width:0;border:1px solid var(--ovl-line);border-radius:14px;overflow:hidden}.ovl-code-top{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:16px 20px;background:#f5f7fb}.ovl-code-top>div{min-width:0}.ovl-code-top strong{display:block;font-size:15px;overflow-wrap:anywhere}.ovl-location{display:block;font-size:12px;font-weight:700;color:#1d4ed8;letter-spacing:.04em;margin-top:4px}.ovl-code-top .ovl-button{min-width:128px;flex-shrink:0}.ovl-code pre{margin:0;padding:24px;background:#141a24;color:#e1e8f2;font:15px/1.7 ui-monospace,SFMono-Regular,Consolas,monospace;overflow-x:auto;white-space:pre;max-width:100%;tab-size:4}.ovl-code pre code{background:transparent;color:inherit;font:inherit;padding:0;border:0;white-space:pre;word-break:normal}.ovl-edit{font-size:14px;background:#eef4ff;padding:12px 20px;margin:0!important}.ovl-expected{padding:8px 20px;background:#fff}.ovl-expected summary{font-size:14px}.ovl-expected pre{background:#f5f7fb;color:var(--ovl-ink);border-radius:8px;margin-bottom:12px;font-size:13px;white-space:pre-wrap;overflow-wrap:anywhere}.ovl-diagram{margin:26px 0;max-width:100%}.ovl-diagram img{max-width:100%;height:auto}.ovl-diagram figcaption{font-size:13px;color:var(--ovl-muted);margin-top:8px}.ovl-exercise{background:#f5f7fb}.ovl-exercise details{margin-top:18px}.ovl-sources{font-size:14px;color:var(--ovl-muted);border-top:1px solid var(--ovl-line);padding-top:26px;margin-bottom:30px}.ovl-pager{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.ovl-copy-status{position:fixed;bottom:20px;left:50%;transform:translateX(-50%);z-index:10000;max-width:calc(100% - 32px);padding:12px 18px;border-radius:10px;background:#172033;color:#fff;box-shadow:0 4px 24px #17203325;font-size:14px}.ovl-copy-status:empty{display:none}.ovl-page .ovn-desktop a[href$="/learn/"]{background:#172033;color:#fff}.ovl-page .ovn-desktop a[href$="/learn/"]:hover{background:#2563eb;color:#fff}@media(hover:hover){.ovl-shell .ovl-button:hover{background:var(--ovl-blue);border-color:var(--ovl-blue);color:#fff}.ovl-hero:hover,.ovl-panel:hover{border-color:#2563eb}}@media(max-width:900px){.ovl-hero{grid-template-columns:1fr}.ovl-hero-art{max-width:520px}.ovl-layout{grid-template-columns:1fr}.ovl-sidebar{position:static}.ovl-sidebar ol{columns:2}.ovl-section{scroll-margin-top:80px}}@media(max-width:600px){.ovl-shell{padding:28px 16px 48px;font-size:16px}.ovl-hero,.ovl-panel{padding:22px}.ovl-grid{grid-template-columns:1fr}.ovl-terms dl{grid-template-columns:1fr;gap:4px}.ovl-terms dd{margin-bottom:12px}.ovl-sidebar ol{columns:1}.ovl-code-top{align-items:stretch;flex-direction:column;padding:16px}.ovl-code-top .ovl-button{width:100%}.ovl-code pre{padding:20px 16px;font-size:14px}.ovl-actions{display:grid;grid-template-columns:1fr}.ovl-actions .ovl-button{width:100%}.ovl-pager{grid-template-columns:1fr}.ovl-intro{font-size:17px}.ovl-note{padding:18px}.ovl-breadcrumb{font-size:13px}}@media(prefers-reduced-motion:reduce){.ovl-shell *{transition:none!important}}@media print{.ovl-sidebar,.ovl-actions,.ovl-pager,.ovl-copy-status,.ovn-header,.ovn-footer,[data-ovl-copy]{display:none!important}.ovl-layout{display:block}.ovl-shell{max-width:none;padding:0}.ovl-code pre{white-space:pre-wrap;overflow-wrap:anywhere;color:#000;background:#fff}.ovl-hero-art{display:none}.ovl-expected{display:block}}

/* Shared neutral buttons and the same blue interaction used across OpenViST. */
.ovl-card{transition:border-color .15s,background .15s,box-shadow .15s}
.ovl-shell .ovl-card-link{align-self:flex-start;margin-top:auto;width:auto}
.ovl-breadcrumb .ovl-button{min-width:0;min-height:44px;padding:8px 13px;font-size:13px}
.ovl-shell .ovl-breadcrumb{align-items:center}
.ovl-sidebar{max-height:none;overflow:visible}
.ovl-sidebar ol{padding-left:0;list-style:none}
.ovl-shell .ovl-sidebar .ovl-button{width:100%;min-width:0;justify-content:flex-start;text-align:left;padding:10px 12px;font-size:13px}
.ovl-on-page ul,.ovl-sources ul{list-style:none;padding:0;margin:16px 0 0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}
.ovl-on-page li,.ovl-sources li{margin:0!important;min-width:0}
.ovl-shell .ovl-on-page .ovl-button,.ovl-shell .ovl-sources .ovl-button{width:100%;height:100%;min-width:0;justify-content:flex-start;text-align:left}
.ovl-card:focus-visible{border-color:#2563eb;background:#f7faff;box-shadow:0 5px 18px rgba(23,32,51,.04)}
.ovl-card:focus-visible h3{color:#2563eb}
.ovl-card:focus-visible .ovl-card-link{background:#2563eb;border-color:#2563eb;color:#fff}
@media(hover:hover){
 .ovl-card:hover{border-color:#2563eb;background:#f7faff;box-shadow:0 5px 18px rgba(23,32,51,.04)}
 .ovl-card:hover h3{color:#2563eb}
 .ovl-card:hover .ovl-card-link{background:#2563eb;border-color:#2563eb;color:#fff}
}
@media(max-width:900px){.ovl-sidebar{max-height:none;overflow:visible}.ovl-sidebar ol{columns:1;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.ovl-sidebar li{margin:0!important;min-width:0}}
@media(max-width:600px){.ovl-sidebar ol,.ovl-on-page ul,.ovl-sources ul{grid-template-columns:1fr}.ovl-shell .ovl-card-link{width:100%}}
/* Long course outlines remain scrollable on desktop; figures stay inside the article. */
.ovl-diagram img[src*="python-"]{display:block;width:100%;max-width:600px;margin-inline:auto}

.ovl-diagram img[src*="javascript-"]{display:block;width:100%;max-width:600px;margin-inline:auto}

/* Keep the header visible and the full last lesson reachable inside its own scroll region. */
.ovl-sidebar{--ovl-outline-top:110px;top:var(--ovl-outline-top)}
body.admin-bar .ovl-sidebar{--ovl-outline-top:142px}
.ovl-route-body{display:flex;flex-direction:column;max-height:calc(100vh - var(--ovl-outline-top) - 128px);max-height:calc(100dvh - var(--ovl-outline-top) - 128px)}
.ovl-route-scroll{min-height:0;overflow-y:auto;overflow-x:hidden;padding:4px 8px 10px 4px;margin:0 -8px 0 -4px;scrollbar-gutter:stable;scrollbar-width:thin;scrollbar-color:#93a9c5 #e9eef5;overscroll-behavior:contain;scroll-padding-block:8px}
.ovl-route-scroll::-webkit-scrollbar{width:8px}
.ovl-route-scroll::-webkit-scrollbar-track{background:#e9eef5;border-radius:8px}
.ovl-route-scroll::-webkit-scrollbar-thumb{background:#93a9c5;border-radius:8px}
.ovl-shell .ovl-route-scroll ol{margin:0;padding:0 0 4px}
.ovl-route-scroll:focus-visible{outline:2px solid #2563eb;outline-offset:3px;border-radius:6px}
.ovl-shell .ovl-route-hint{flex-shrink:0;margin:12px 0 0;padding-top:10px;border-top:1px solid var(--ovl-line);font-size:12px;line-height:1.5;color:var(--ovl-muted)}
@media(max-width:900px){.ovl-route-body{max-height:none}.ovl-route-scroll{overflow:visible;margin:0;padding:4px;scrollbar-gutter:auto}.ovl-shell .ovl-route-hint{display:none}}