:root{--ink:#2b2e3c;--muted:#616575;--violet:#5c4b8c;--light:#eeebf7;--line:#dcdeE6;--night:#303345}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;font:16px/1.85 -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:#fff}h1,h2,h3,p,figure{margin:0 0 1em}h1,h2,h3{line-height:1.35;letter-spacing:-.02em}a{color:var(--violet);text-underline-offset:4px;overflow-wrap:anywhere}a:hover{color:#352653}a:focus-visible,summary:focus-visible{outline:3px solid #a299db;outline-offset:5px}.skip{position:absolute;top:-80px;padding:12px;background:#fff;z-index:10}.skip:focus{top:0}.masthead{max-width:1440px;padding:24px 50px;margin:auto;display:flex;justify-content:space-between;align-items:center;gap:25px}.brand{font-size:22px;color:var(--ink);text-decoration:none;display:flex;align-items:center;gap:9px;font-weight:650}.brand b{font-size:18px;font-weight:450;letter-spacing:.01em}.cloud-symbol{width:25px;height:17px;border:2px solid #8573b1;border-radius:16px 16px 8px 8px;display:inline-block;margin-right:5px;transform:skewX(-8deg)}.masthead nav{display:flex;gap:28px;font-size:13px}.masthead nav a{color:var(--ink);text-decoration:none}.mobile-navigation{display:none}.opening{max-width:1440px;margin:auto;display:grid;grid-template-columns:.92fr 1.1fr;background:var(--night);min-height:480px}.opening-copy{padding:64px 50px 45px;color:#fff}.eyebrow{color:var(--violet);font-size:10px;letter-spacing:.15em;font-weight:700;margin-bottom:18px}.opening-copy .eyebrow{color:#c7bdf2}.opening h1{font-size:46px;line-height:1.3;font-weight:650}.opening h1 span{font-size:31px;letter-spacing:-.03em;font-weight:450}.opening-summary{font-size:16px;line-height:1.9;color:#d6d8e3;margin:27px 0}.primary{display:inline-block;background:#e6dfff;color:#282139;padding:12px 24px;text-decoration:none;font-size:13px;font-weight:650;border:1px solid transparent}.primary:hover{background:#fff;color:#2f244c}.guide-identity{font-size:11px;color:#bbbcc9;margin:18px 0 0}.opening-photo{min-width:0;position:relative;overflow:hidden}.opening-photo img{width:100%;height:100%;object-fit:cover;object-position:46% center;display:block}.journey-navigation{max-width:1340px;margin:auto;display:grid;grid-template-columns:repeat(3,1fr);gap:20px;border-bottom:1px solid var(--line);padding:25px 0}.journey-navigation a{font-size:14px;text-decoration:none;color:var(--ink);display:flex;align-items:center;gap:15px}.journey-navigation span{font-size:11px;background:var(--light);color:var(--violet);padding:4px 12px}.journey-layout{max-width:1240px;display:grid;grid-template-columns:230px 1fr;gap:95px;margin:65px auto}.journey-side{align-self:start;position:sticky;top:25px;border-top:3px solid #8c7db8;padding-top:22px}.journey-side>span{font-size:11px;color:var(--violet)}.journey-side>p{font-size:18px;margin-top:15px}.journey-side .small-note{font-size:12px;color:var(--muted);max-width:180px}.checkpoint{padding:0 0 55px;margin-bottom:45px;border-bottom:1px solid var(--line)}.checkpoint-heading h2{font-size:29px;font-weight:600;margin-bottom:23px}.checkpoint-answer{font-size:17px;color:#474c5e}.purpose-table{margin:28px 0;background:#f5f5fa;padding:0 24px}.purpose-row{display:grid;grid-template-columns:160px 1fr;gap:25px;border-bottom:1px solid #dfe0e8;padding:18px 0;font-size:14px}.purpose-row:last-child{border-bottom:0}.purpose-row p{margin:0;color:var(--muted)}.purpose-row strong{font-weight:600}.table-heading{font-size:11px;color:var(--muted);padding:13px 0}.page-observation{font-size:14px;line-height:1.9;color:var(--muted);max-width:760px}.text-action{font-size:13px;display:inline-block;margin-top:8px}.installation-notes{display:grid;grid-template-columns:1fr;gap:25px;padding:8px 0}.installation-notes>div{display:grid;grid-template-columns:150px 1fr;gap:35px}.installation-notes h3{font-size:18px;font-weight:600;margin:0}.installation-notes p{font-size:15px;color:var(--muted);margin:0}.installation-boundary{background:#eeebf7;padding:23px 27px;margin-top:25px;border-left:3px solid #8672b3}.installation-boundary strong{font-size:15px}.installation-boundary p{font-size:14px;color:#5c5571;margin:7px 0 0}.account-checkpoint>p{font-size:16px;color:var(--muted)}.login-results{margin:27px 0;padding:0 0 0 25px;border-left:2px solid #bdb0d9}.login-results dt{font-size:17px;font-weight:650}.login-results dd{font-size:15px;color:var(--muted);margin:9px 0 25px}.account-action{background:var(--night);color:#fff}.account-action:hover{background:#514469;color:#fff}.compact-help{padding:0 0 15px}.compact-help h2{font-size:22px}.compact-help details{border-bottom:1px solid var(--line);padding:16px 0}.compact-help summary{cursor:pointer;font-size:16px}.compact-help p{font-size:14px;color:var(--muted);margin:14px 0 0}.reading-support{max-width:1240px;margin:0 auto 60px;padding-top:30px;border-top:1px solid var(--line)}.support-title{display:flex;align-items:baseline;justify-content:space-between;gap:20px}.support-title h2{font-size:24px;font-weight:600}.support-title>a{font-size:12px}.guide-link{padding:25px 0;border-bottom:1px solid var(--line);display:grid;grid-template-columns:1fr 95px;gap:35px}.guide-topic{font-size:10px;letter-spacing:.08em;color:var(--violet);margin-bottom:10px}.guide-link h3{font-size:20px;font-weight:600;margin-bottom:8px}.guide-link h3 a{text-decoration:none;color:var(--ink)}.guide-link p:last-child{font-size:13px;color:var(--muted);margin:0}.guide-link time{font-size:11px;color:var(--muted);padding-top:30px;white-space:nowrap}.site-end{border-top:1px solid var(--line);background:#f1f2f7;padding:35px max(50px,calc((100vw - 1240px)/2));display:grid;grid-template-columns:1fr 1fr;gap:24px}.end-brand{font-size:22px;font-weight:650;color:var(--ink);text-decoration:none}.site-end>div>p{font-size:12px;color:var(--muted);margin:8px 0 0}.site-end nav{display:flex;justify-content:flex-end;gap:25px;font-size:12px}.site-end nav a{color:var(--ink)}.identity-line{grid-column:1/-1;border-top:1px solid #dcdde8;padding-top:20px;color:var(--muted);font-size:11px;margin:0}.lesson-main{max-width:1240px;margin:auto;padding:25px 0 65px}.breadcrumbs{display:flex;flex-wrap:wrap;gap:12px;font-size:12px;margin-bottom:32px;color:var(--muted)}.lesson-heading{background:#f1eff8;padding:40px 44px;max-width:1130px;margin:0 0 35px}.lesson-heading h1{font-size:37px;font-weight:600;max-width:850px}.lesson-lead{font-size:17px;color:var(--muted);max-width:840px}.lesson-heading time{font-size:11px;color:var(--muted)}.lesson-layout{display:grid;grid-template-columns:220px 1fr;gap:55px}.lesson-outline{align-self:start;position:sticky;top:25px;padding:12px 0;font-size:12px}.lesson-outline>p{font-weight:650;color:var(--muted);margin-bottom:15px}.lesson-outline nav{display:flex;flex-direction:column;gap:15px;border-left:1px solid var(--line);padding-left:20px}.lesson-outline a{text-decoration:none;line-height:1.8;max-width:180px}.lesson-content{max-width:810px;font-size:17px;line-height:1.95}.direct-answer{border-left:3px solid #9280b8;padding:8px 0 8px 25px;color:#4b4361;margin-bottom:36px}.lesson-content>section{margin:36px 0}.lesson-content h2{font-size:26px;font-weight:600}.result-pairs{margin:25px 0;background:#f4f3f8;padding:25px}.result-pairs dt{font-weight:650}.result-pairs dd{margin:8px 0 25px;color:var(--muted)}.result-pairs dd:last-child{margin-bottom:0}code{font:inherit;font-weight:600;overflow-wrap:anywhere}.source-note{font-size:12px;color:var(--muted);border-top:1px solid var(--line);padding-top:25px;margin-top:40px}.source-note h2{font-size:19px}.information{max-width:1100px;min-height:65vh;margin:auto;padding:55px 45px 75px}.information h1{font-size:36px}.information h2{font-size:25px;margin-top:35px}.information>p{max-width:820px}@media(max-width:1440px){.journey-navigation{margin-left:50px;margin-right:50px}.journey-layout,.reading-support,.lesson-main{margin-left:50px;margin-right:50px}.journey-layout{gap:65px;grid-template-columns:200px 1fr}.opening h1{font-size:40px}.opening h1 span{font-size:28px}}@media(max-width:950px){.opening{grid-template-columns:1fr 1fr;min-height:430px}.opening-copy{padding:45px 30px}.opening h1{font-size:35px}.opening h1 span{font-size:24px}.opening-summary{font-size:14px}.journey-navigation{gap:12px}.journey-navigation a{font-size:12px;gap:8px}.journey-layout{grid-template-columns:145px 1fr;gap:40px}.journey-side>p{font-size:16px}.purpose-row{grid-template-columns:115px 1fr;gap:20px}.installation-notes>div{grid-template-columns:1fr;gap:8px}.lesson-layout{grid-template-columns:170px 1fr;gap:35px}}@media(max-width:650px){.masthead{padding:18px 21px;gap:15px;position:relative}.masthead>nav{display:none}.mobile-navigation{display:block}.mobile-navigation summary{cursor:pointer;font-size:12px;padding:4px 9px}.mobile-navigation nav{position:absolute;right:21px;top:62px;z-index:10;display:flex;flex-direction:column;gap:16px;background:#fff;border:1px solid var(--line);padding:20px 25px;box-shadow:0 12px 25px #292d3b12}.mobile-navigation nav a:last-child{display:block}.brand{font-size:20px;gap:6px}.brand b{font-size:16px}.cloud-symbol{width:21px;height:15px;margin-right:3px}.masthead nav{gap:14px;font-size:11px}.masthead nav a:last-child{display:none}.opening{display:flex;flex-direction:column;min-height:0}.opening-copy{padding:31px 23px 30px}.eyebrow{font-size:9px;margin-bottom:17px}.opening h1{font-size:33px}.opening h1 span{font-size:26px}.opening-summary{font-size:14px;margin:20px 0}.primary{font-size:12px;padding:11px 20px}.guide-identity{font-size:10px;margin-top:16px}.opening-photo{height:235px}.opening-photo img{object-position:48% center}.journey-navigation{margin:0 21px;padding:20px 0;gap:12px}.journey-navigation a{display:block;font-size:10px;line-height:1.8}.journey-navigation span{display:block;width:fit-content;font-size:10px;margin-bottom:7px;padding:3px 10px}.journey-layout{display:block;margin:32px 21px}.journey-side{position:static;display:none}.checkpoint{padding-bottom:32px;margin-bottom:32px}.checkpoint-heading h2{font-size:26px;margin-bottom:20px}.checkpoint-answer{font-size:15px}.purpose-table{padding:0 17px;margin:23px 0}.purpose-row{grid-template-columns:1fr;gap:7px;font-size:14px;padding:17px 0}.table-heading{display:none}.page-observation{font-size:13px}.installation-notes{gap:24px}.installation-notes h3{font-size:18px}.installation-notes p{font-size:14px}.installation-boundary{padding:20px;margin-top:20px}.installation-boundary strong{font-size:14px}.installation-boundary p{font-size:13px}.account-checkpoint>p{font-size:15px}.login-results{padding-left:20px}.login-results dt{font-size:16px}.login-results dd{font-size:14px}.compact-help summary{font-size:15px}.compact-help p{font-size:13px}.reading-support{margin:35px 21px}.support-title h2{font-size:22px}.guide-link{display:block;padding:23px 0}.guide-link h3{font-size:19px}.guide-link time{display:block;padding:0;margin-top:13px}.site-end{display:block;padding:30px 21px}.site-end nav{justify-content:flex-start;gap:24px;margin:24px 0}.identity-line{font-size:10px}.lesson-main{padding:23px 0 45px;margin:0 21px}.breadcrumbs{font-size:11px;gap:10px;margin-bottom:25px}.lesson-heading{padding:26px 22px;margin:0 -21px 25px}.lesson-heading h1{font-size:29px}.lesson-lead{font-size:15px}.lesson-layout{display:block}.lesson-outline{position:static;padding:0 0 20px;margin-bottom:25px;border-bottom:1px solid var(--line)}.lesson-outline>p{font-size:11px;margin-bottom:12px}.lesson-outline nav{gap:10px;padding-left:14px}.lesson-outline a{max-width:100%;font-size:12px}.lesson-content{font-size:16px}.direct-answer{padding-left:20px;margin-bottom:28px}.lesson-content>section{margin:30px 0}.lesson-content h2{font-size:23px}.result-pairs{padding:20px}.source-note{font-size:12px}.information{padding:35px 21px 55px}.information h1{font-size:30px}.information h2{font-size:24px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}