:root{--ink:#080f34;--blue:#246bff;--muted:#53627f;--paper:#f3f6fc;--line:#cfdaeb;--navy:#080d20}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);background:var(--paper);font:16px/1.55 -apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif}a{color:inherit;text-decoration:none}.shell{width:min(1260px,calc(100% - 80px));margin:auto}.skip{position:absolute;left:-9999px}.skip:focus{left:20px;top:10px;background:white;padding:10px;z-index:10}.top{border-bottom:1px solid var(--line)}.top-inner{min-height:92px;display:flex;align-items:center;gap:32px}.top img{display:block}.top nav{display:flex;gap:30px;margin-left:auto;font-size:14px;color:var(--muted)}.top nav .active{color:var(--blue);font-weight:700}.top-action,.end-card a{background:var(--ink);color:white;padding:13px 18px;font-size:14px;font-weight:700}.top-action span{margin-left:12px}.intro{padding:76px 0 62px;display:flex;align-items:end;justify-content:space-between;gap:50px}.eyebrow{font-size:11px;letter-spacing:1.15px;font-weight:800;color:var(--blue);margin:0 0 14px}.eyebrow span{color:#9baecb;margin:0 7px}.intro h1{font-size:clamp(48px,6vw,79px);line-height:.98;letter-spacing:-.065em;margin:0}.intro h1 em{font-style:normal;color:var(--blue)}.intro>div>p:last-child{font-size:18px;color:var(--muted);max-width:550px;margin:22px 0 0}.intro-note{display:flex;gap:15px;max-width:308px;padding:20px;border-left:2px solid var(--blue)}.intro-note .note-icon{font-size:21px;color:var(--blue)}.intro-note strong{font-size:14px}.intro-note p{margin:5px 0 0!important;font-size:13px!important;line-height:1.55}.learning-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:52px;align-items:start}.player{aspect-ratio:16/9;background:var(--navy);box-shadow:12px 12px 0 #dce8fa}.player iframe{width:100%;height:100%;border:0}.lesson-heading{padding:36px 0 25px;display:flex;justify-content:space-between;align-items:start;gap:30px}.lesson h2,.chapters h2{font-size:clamp(27px,3vw,39px);letter-spacing:-.04em;line-height:1.1;margin:0}.lesson-heading p:last-child,.steps-header>p:last-child{color:var(--muted);margin:12px 0 0}.lesson-heading>a{white-space:nowrap;color:var(--blue);font-size:13px;font-weight:700}.notice{background:#e3edfc;border-left:3px solid var(--blue);padding:19px 23px;font-size:14px}.notice p{margin:4px 0 0;color:var(--muted)}.chapters{background:var(--navy);color:white;padding:28px;position:sticky;top:24px}.chapters .eyebrow{color:#79aaff}.chapters h2{font-size:27px}.chapters>p:not(.eyebrow){color:#aab9d4;font-size:13px}.chapter-link{border-top:1px solid #293552;display:flex;gap:15px;align-items:center;padding:13px 0;font-size:13px;font-weight:650}.chapter-link:hover,.chapter-link:focus{color:#caff52}.chapter-link span{color:#8da8d8;font-size:11px;font-variant-numeric:tabular-nums;min-width:38px}.chapter-help{border-top:1px solid #293552;padding-top:17px}.steps-header{padding:82px 0 34px}.steps{border-top:1px solid var(--line)}.steps article{display:grid;grid-template-columns:58px 1fr;gap:20px;border-bottom:1px solid var(--line);padding:27px 0}.steps article>span{color:#9cacc4;font-size:19px}.steps h3{font-size:23px;letter-spacing:-.035em;margin:0 0 9px}.steps p{color:var(--muted);margin:0;max-width:690px}.steps strong{color:var(--ink)}.steps .callout{background:#e4edfb;margin-top:16px;padding:14px 16px;font-size:14px}.transcript{margin:34px 0;border:1px solid var(--line);background:#fff}.transcript summary{cursor:pointer;padding:19px 22px;font-weight:700;display:flex;justify-content:space-between;list-style:none}.transcript summary span{color:var(--blue);font-size:22px;line-height:1}.transcript[open] summary span{transform:rotate(45deg)}.transcript #transcript-body{padding:0 22px 22px;color:var(--muted);font-size:14px}.transcript p{margin:0 0 12px}.end-card{margin:48px 0 90px;padding:35px;background:var(--blue);color:white;display:flex;justify-content:space-between;gap:24px;align-items:center}.end-card .eyebrow{color:#d5e6ff}.end-card p:last-child{margin:10px 0 0;color:#dce8ff}.end-card a{white-space:nowrap;background:#d9f531;color:var(--ink)}.footer{border-top:1px solid var(--line);padding:28px 0 36px;display:flex;align-items:center;gap:30px;font-size:12px;color:var(--muted)}.footer a{margin-left:auto;color:var(--blue);font-weight:700}a:focus-visible,summary:focus-visible{outline:3px solid #66a5ff;outline-offset:4px}@media(max-width:900px){.learning-layout{grid-template-columns:1fr}.chapters{position:static;grid-row:1}.intro-note{display:none}.chapters #chapter-list{display:grid;grid-template-columns:1fr 1fr;column-gap:25px}}@media(max-width:600px){.shell{width:calc(100% - 36px)}.top-inner{min-height:75px;gap:14px}.top img{width:130px}.top nav{gap:12px;font-size:12px}.top-action{display:none}.intro{padding:50px 0 38px}.intro h1{font-size:47px}.intro>div>p:last-child{font-size:16px}.learning-layout{gap:28px}.chapters #chapter-list{grid-template-columns:1fr 1fr;column-gap:16px}.chapter-link{font-size:12px;gap:7px}.lesson-heading,.end-card{display:block}.lesson-heading>a{display:inline-block;margin-top:15px}.steps-header{padding-top:60px}.steps article{grid-template-columns:38px 1fr;gap:10px}.end-card a{display:inline-block;margin-top:20px}.footer{flex-wrap:wrap;gap:15px}.footer a{margin-left:0}}
/* The hub grows as more guides are added. */
.hub-intro{padding-bottom:76px}.hub-library{padding-bottom:110px}.library-heading{display:flex;justify-content:space-between;align-items:end;border-bottom:1px solid var(--line);padding-bottom:25px;margin-bottom:30px}.library-heading h2{font-size:clamp(34px,4vw,50px);letter-spacing:-.05em;line-height:1;margin:0}.library-heading p:last-child{color:var(--muted);margin:12px 0 0}.guide-count{font-size:11px;letter-spacing:1px;font-weight:800;color:var(--muted)}.guide-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}.guide-card{display:block;background:#fff;border:1px solid var(--line);transition:transform .2s,box-shadow .2s;overflow:hidden}.guide-card:hover{transform:translateY(-4px);box-shadow:10px 12px 0 #dce8fa}.guide-image{position:relative;aspect-ratio:16/9;background:var(--navy);overflow:hidden}.guide-image img{width:100%;height:100%;object-fit:cover;display:block}.guide-play{position:absolute;right:17px;bottom:17px;border-radius:50%;width:45px;height:45px;display:grid;place-items:center;background:#d9f531;color:#080f34;font-size:14px;padding-left:2px}.guide-body{padding:25px}.guide-meta{display:flex;justify-content:space-between;gap:8px;color:#52688d;font-size:10px;font-weight:800;letter-spacing:.08em}.guide-body h3{font-size:25px;line-height:1.15;letter-spacing:-.04em;margin:20px 0 10px}.guide-body p{font-size:14px;color:var(--muted);margin:0;min-height:67px}.guide-link{display:flex;justify-content:space-between;border-top:1px solid var(--line);padding-top:17px;margin-top:25px;color:var(--blue);font-weight:700;font-size:13px}.library-foot{border-top:1px solid var(--line);margin-top:75px;padding-top:25px;display:flex;justify-content:space-between;color:var(--muted);font-size:12px}.library-foot span{font-weight:800;letter-spacing:1px}.library-foot p{margin:0}@media(max-width:900px){.guide-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:600px){.hub-intro{padding-bottom:50px}.hub-library{padding-bottom:65px}.guide-grid{grid-template-columns:1fr}.library-foot{display:block}.library-foot p{margin-top:8px}.guide-body p{min-height:0}}
@media(prefers-color-scheme:dark){:root{color-scheme:dark;--ink:#f1f4fc;--blue:#78bfff;--muted:#b5c2d8;--paper:#090d1b;--line:#2d3950;--navy:#101b31}.top-action{background:#2aadfe;color:#000034}.intro h1 em,.eyebrow,.top nav .active,.guide-link,.lesson-heading>a,.footer a{color:#78bfff}.guide-card,.transcript{background:#142137}.guide-card:hover{box-shadow:10px 12px 0 #050915}.guide-meta{color:#a6bcdb}.guide-play{color:#080f34}.notice,.steps .callout{background:#17263e}.player{box-shadow:12px 12px 0 #050915}.end-card{background:#195bc9;color:white}.end-card a{color:#080f34}.skip:focus{background:#f1f4fc;color:#000034}}

/* Put the player first on smaller screens; reveal chapters on request. */
.mobile-chapters { display: none; }
@media (max-width: 900px) {
  .learning-layout { display: block; }
  .chapters { display: none; }
  .mobile-chapters { display: block; margin-top: 24px; background: var(--navy); color: #fff; padding: 0 20px; }
  .mobile-chapters summary { cursor: pointer; list-style: none; display: flex; align-items: center; justify-content: space-between; padding: 17px 0; font-weight: 700; }
  .mobile-chapters summary::-webkit-details-marker { display: none; }
  .mobile-chapters summary span { color: #79aaff; font-size: 23px; line-height: 1; }
  .mobile-chapters[open] summary span { transform: rotate(45deg); }
  .mobile-chapter-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 18px; padding-bottom: 12px; }
}
@media (max-width: 390px) { .mobile-chapter-list { grid-template-columns: 1fr; } }