:root{--bg:#fbfaf4;--surface:#ffffff;--ink:#1c2939;--muted:#4c596a;--accent:#1f57a5;--accent-ink:#ffffff;--accent2:#c8323a;--line:#cfdeef;--hero-ink:#1c2939;--r:3px;--maxw:1180px;--measure:68ch;--hf:'Karma', Georgia, serif;--bf:'Source Sans 3', system-ui, sans-serif}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:17px/1.65 var(--bf)}
img{max-width:100%;height:auto;display:block}
a{color:var(--accent);text-underline-offset:.18em}
h1,h2,h3,h4{font-family:var(--hf);line-height:1.18;margin:1.6em 0 .5em;font-weight:600;letter-spacing:-.01em}
h1{font-size:clamp(2rem,5vw,3.5rem);margin-top:0}
h2{font-size:clamp(1.4rem,3vw,2rem)}h3{font-size:1.2rem}
p,ul,ol,table,details{margin:0 0 1.1em}
.wrap{max-width:max(var(--maxw),min(88vw,1760px));margin:0 auto;padding:0 20px}
@media(min-width:1800px){body article.prose>:is(p,ul,ol,h2,h3,h4,blockquote,dl,details,.callout,.disclosure,.table-wrap){max-width:52rem}}
.skip{position:absolute;left:-999px}.skip:focus{left:10px;top:10px;background:var(--surface);padding:8px;z-index:9}
header.site{border-bottom:1px solid var(--line);background:var(--surface)}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;gap:16px;padding-top:14px;padding-bottom:14px;flex-wrap:wrap}
.brand{font-family:var(--hf);font-weight:800;font-size:1.25rem;color:var(--ink);text-decoration:none;display:flex;align-items:center;gap:10px}
.brand svg{flex:none}
nav.main ul{list-style:none;display:flex;flex-wrap:wrap;gap:4px 18px;margin:0;padding:0}
nav.main a{color:var(--ink);text-decoration:none;font-size:.95rem;padding:4px 0;border-bottom:2px solid transparent}
nav.main a[aria-current]{border-color:var(--accent)}
.menu-btn{display:none}
@media(max-width:760px){.menu-btn{display:inline-block;background:none;border:1px solid var(--line);color:var(--ink);border-radius:var(--r);padding:6px 12px;font:inherit}
nav.main{width:100%;display:none}nav.main.open{display:block}nav.main ul{flex-direction:column;gap:6px}}
.hero{position:relative;overflow:hidden}
.hero .wrap{padding-top:56px;padding-bottom:56px}
.hero .lead{font-size:1.18rem;color:var(--muted);max-width:60ch}
.hero.full{color:var(--hero-ink);min-height:440px;display:flex;align-items:flex-end}
.hero.full img.bg{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.hero.full::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(0,0,0,.05),rgba(0,0,0,.62))}
.hero.full .wrap{position:relative;z-index:1;width:100%}.hero.full .lead{color:inherit;opacity:.92}
.hero.split .wrap{display:grid;grid-template-columns:1.1fr .9fr;gap:40px;align-items:center}
.hero.split img{border-radius:var(--r);aspect-ratio:4/3;object-fit:cover;width:100%}
.hero.banner img{width:100%;max-height:380px;object-fit:cover;border-radius:var(--r);margin-top:28px}
.hero.plain{background:var(--surface);border-bottom:1px solid var(--line)}
@media(max-width:760px){.hero.split .wrap{grid-template-columns:1fr}.hero.full{min-height:340px}.hero .wrap{padding-top:36px;padding-bottom:36px}}
.page{display:grid;gap:48px;padding-top:40px;padding-bottom:64px}
.page.toc-layout{grid-template-columns:220px minmax(0,1fr)}
.page.toc-layout .toc{position:sticky;top:20px;align-self:start;font-size:.92rem;border-left:3px solid var(--accent);padding-left:14px}
.page.toc-layout .toc ul{list-style:none;padding:0;margin:0}.page.toc-layout .toc li{margin:.35em 0}
.page.toc-layout .toc a{color:var(--muted);text-decoration:none}
@media(max-width:860px){.page.toc-layout{grid-template-columns:1fr}.page.toc-layout .toc{position:static}}
/* Content uses the full container width (cards, grids, tables); only running text keeps a readable measure. */
article.prose{max-width:none;min-width:0}
article.prose>:is(p,ul,ol,h2,h3,h4,blockquote,dl,details,.callout,.disclosure,.table-wrap){max-width:47.5rem;margin-left:auto;margin-right:auto}
.page.toc-layout article.prose>*{margin-left:0;margin-right:0}
/* A heading that introduces a full-width block (cards, grid, table) lines up with that block, not the text column. */
body article.prose>:is(h2,h3):has(+ :is(.cards,nav,div,table,section,ul.grid)){max-width:none;margin-left:0;margin-right:0}
.page.wide article.prose>*{max-width:none}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px;margin:0 0 1.4em}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:20px}
.card h3{margin-top:0}.card p:last-child{margin-bottom:0}
a.card{display:block;color:var(--ink);text-decoration:none}a.card:hover{border-color:var(--accent)}
.callout{border-left:4px solid var(--accent2);background:var(--surface);padding:14px 18px;border-radius:0 var(--r) var(--r) 0;margin:0 0 1.2em}
.table-wrap{overflow-x:auto;margin:0 0 1.2em}
table{border-collapse:collapse;width:100%;font-size:.95rem}
th,td{border-bottom:1px solid var(--line);padding:9px 10px;text-align:left;vertical-align:top}
th{font-family:var(--hf);background:var(--surface)}
details{border:1px solid var(--line);border-radius:var(--r);padding:10px 16px;background:var(--surface)}
summary{cursor:pointer;font-weight:600}
.steps{counter-reset:s;list-style:none;padding:0}.steps li{counter-increment:s;position:relative;padding-left:44px;margin-bottom:1em}
.steps li::before{content:counter(s);position:absolute;left:0;top:0;width:30px;height:30px;border-radius:50%;background:var(--accent);color:var(--accent-ink);display:grid;place-items:center;font-weight:700;font-size:.9rem}
.btn{display:inline-block;background:var(--accent);color:var(--accent-ink);padding:10px 18px;border-radius:var(--r);text-decoration:none;font-weight:600;border:0;font:inherit;cursor:pointer}
.aff{border:1px dashed var(--accent);border-radius:var(--r);padding:16px 18px;margin:0 0 1.2em;background:var(--surface)}
.aff .tag{font-size:.75rem;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}
.disclosure{font-size:.88rem;color:var(--muted);border:1px solid var(--line);border-radius:var(--r);padding:10px 14px;margin:0 0 1.6em}
.meta{font-size:.88rem;color:var(--muted)}
dl dt{font-family:var(--hf);font-weight:700;margin-top:1em}dl dd{margin:.2em 0 0 0;color:var(--ink)}
footer.site{border-top:1px solid var(--line);background:var(--surface);font-size:.92rem;color:var(--muted)}
footer.site .wrap{padding-top:32px;padding-bottom:32px;display:grid;gap:18px}
footer.site ul{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:6px 18px}
footer.site a{color:var(--muted)}
.ps{font-size:17.5px}
/* Header: a white strip with a blue binding edge */
.ps header.site{background:#fff;border-bottom:0;box-shadow:inset 0 4px 0 var(--accent),0 1px 0 var(--line)}
.ps header.site .wrap{padding-top:18px;padding-bottom:14px}
.ps .brand{font-weight:700;font-size:1.45rem;color:#173f78;letter-spacing:0}
.ps nav.main a{font-weight:600;font-size:.93rem;color:#2a3a50}
.ps nav.main a:hover{color:var(--accent)}
.ps nav.main a[aria-current]{border-color:var(--accent2);color:var(--accent)}
/* Main area: faint ruled paper with a red margin line on wide screens */
.ps main{background:repeating-linear-gradient(180deg,transparent 0 33px,#edf3fa 33px 34px),var(--bg)}
@media(min-width:1100px){.ps main{background:linear-gradient(90deg,transparent 0 58px,rgba(200,50,58,.45) 58px 60px,transparent 60px),repeating-linear-gradient(180deg,transparent 0 33px,#edf3fa 33px 34px),var(--bg)}}
/* Hero: a notebook page */
.ps .hero.plain{background:linear-gradient(90deg,transparent 0 58px,rgba(200,50,58,.55) 58px 60px,transparent 60px),repeating-linear-gradient(180deg,#fff 0 31px,#cfe0f3 31px 32px);border-bottom:2px solid var(--line)}
@media(max-width:760px){.ps .hero.plain{background:linear-gradient(90deg,transparent 0 12px,rgba(200,50,58,.55) 12px 14px,transparent 14px),repeating-linear-gradient(180deg,#fff 0 31px,#cfe0f3 31px 32px)}}
.ps .hero .wrap{padding-top:52px;padding-bottom:52px}
.ps .hero .kicker{display:inline-block;margin:0 0 1em;font-weight:700;font-size:.78rem;letter-spacing:.14em;text-transform:uppercase;color:var(--accent2);border-bottom:2px solid var(--accent2);padding-bottom:2px}
.ps .hero h1{color:#173f78;max-width:21ch;line-height:1.12}
.ps .hero .lead{color:#33435a;max-width:60ch;font-size:1.2rem}
.ps .hero.plain .wrap:has(.art){display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);grid-template-rows:1fr auto auto auto 1fr;column-gap:64px}
.ps .hero.plain .wrap:has(.art)>:not(.art){grid-column:1}
.ps .hero.plain .wrap:has(.art)>.kicker{grid-row:2;justify-self:start}.ps .hero.plain .wrap:has(.art)>h1{grid-row:3}.ps .hero.plain .wrap:has(.art)>.lead{grid-row:4}
.ps .hero.plain .art{grid-column:2;grid-row:1/6;align-self:center}
.ps .art img{aspect-ratio:4/3;object-fit:cover;width:100%;border:8px solid #fff;box-shadow:0 1px 0 var(--line),0 14px 30px rgba(23,63,120,.16);transform:rotate(-1deg)}
.ps .nb{position:relative;background:#fff;border:1px solid #c9d9ec;padding:20px 18px 14px 48px;box-shadow:6px 6px 0 #e3ecf7,0 14px 30px rgba(23,63,120,.12);transform:rotate(-.8deg)}
.ps .nb::before{content:"";position:absolute;left:14px;top:0;bottom:0;width:14px;background:radial-gradient(circle at 7px 50%,#fbfaf4 5px,#b9cbe2 5.5px,transparent 6.5px) 0 18px/14px 33.3% repeat-y}
.ps .nb .rv{margin:0;border:0;box-shadow:none;padding:0;background:none}
.ps .nb .rv .fine{display:none}
@media(max-width:860px){.ps .hero.plain .wrap:has(.art){grid-template-columns:1fr;grid-template-rows:none}.ps .hero.plain .wrap:has(.art)>*{grid-row:auto!important}.ps .hero.plain .art{grid-column:1;margin-top:26px}.ps .nb{transform:none}}
/* Headings */
.ps .prose h2{color:#173f78;padding-bottom:.3em;border-bottom:2px solid #cfe0f3;position:relative}
.ps .prose h2::after{content:"";position:absolute;left:0;bottom:-2px;width:64px;height:2px;background:var(--accent2)}
.ps .prose h3{color:var(--accent)}
/* Guide cards: notebook pages with a red margin */
.ps .cards.gd{grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:20px}
.ps .gd a.card{position:relative;padding:20px 20px 18px 54px;border:1px solid #cddcee;border-radius:2px;background:linear-gradient(90deg,transparent 0 40px,rgba(200,50,58,.5) 40px 41.5px,transparent 41.5px),repeating-linear-gradient(180deg,#fff 0 29px,#e4edf8 29px 30px);transition:transform .15s,box-shadow .15s}
.ps .gd a.card:hover{transform:translateY(-2px);box-shadow:0 10px 22px rgba(23,63,120,.14);border-color:var(--accent)}
.ps .gd .no{position:absolute;left:10px;top:20px;font:700 .8rem/1 var(--bf);color:var(--accent2)}
.ps .gd h3{margin:0 0 .3em;color:#173f78;font-size:1.22rem}
.ps .gd p{color:var(--muted);font-size:.96rem}
/* Review plans (signature) */
.ps .rvs{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,460px),1fr));gap:22px;margin:0 0 1.6em}
.ps .rv{margin:0 0 1.6em;background:#fff;border:1px solid #c9d9ec;padding:18px 18px 12px;box-shadow:4px 4px 0 #e3ecf7}
.ps .rvs .rv{margin:0}
.ps .rv figcaption{margin:0 0 10px}
.ps .rv figcaption strong{display:block;font-family:var(--hf);font-size:1.18rem;color:#173f78;line-height:1.25}
.ps .rv figcaption span{display:block;color:var(--muted);font-size:.93rem;margin-top:.2em}
.ps svg.mc{display:block;width:100%;height:auto}
.ps .mc .paper{fill:#fff}.ps .mc .rule{stroke:#cfe0f3;stroke-width:1}
.ps .mc .margin{stroke:#c8323a;stroke-width:1.6;opacity:.75}
.ps .mc .area{fill:rgba(31,87,165,.10)}.ps .mc .ln{fill:none;stroke:#1f57a5;stroke-width:2.6;stroke-linejoin:round}
.ps .mc .rev{fill:#c8323a;stroke:#fff;stroke-width:2}
.ps .mc .test{fill:#173f78}.ps .mc .testline{stroke:#173f78;stroke-width:1.4;stroke-dasharray:4 4}
.ps .mc text{font:600 14px var(--bf);fill:#4c596a}.ps .mc .yl{text-anchor:end}.ps .mc .xl{text-anchor:middle}.ps .mc .cap{text-anchor:end;font-weight:400}
.ps ol.days{list-style:none;margin:10px 0 6px;padding:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(34px,1fr));gap:3px}
.ps ol.days li{border:1px solid #dce7f4;text-align:center;padding:3px 1px;font-size:.72rem;color:#566275;background:#fbfdff}
.ps ol.days li b{display:block;font-weight:600}
.ps ol.days li span{display:block;font-size:.6rem;letter-spacing:.04em;text-transform:uppercase;font-weight:700}
.ps ol.days li.l{background:#1f57a5;border-color:#1f57a5;color:#fff}
.ps ol.days li.r{background:#fdecec;border-color:#e7a3a6;color:#9b2129}
.ps ol.days li.t{background:#173f78;border-color:#173f78;color:#fff}
.ps .rv .fine{font-size:.8rem;color:var(--muted);margin:.4em 0 0}
/* Tables, callouts, steps, FAQ */
.ps th{background:#eaf1fa;color:#173f78;font-family:var(--bf);font-size:.84rem;text-transform:uppercase;letter-spacing:.06em}
.ps td{background:rgba(255,255,255,.7)}
.ps .callout{border-left:4px solid var(--accent2);background:#fff;box-shadow:inset 0 0 0 1px #f0d6d7}
.ps .steps li::before{background:#fff;color:var(--accent2);border:2px solid var(--accent2);border-radius:50%}
.ps details{background:#fff;border-color:#cddcee;border-radius:2px;margin-bottom:.6em}
.ps summary{color:#173f78}
.ps .ph{margin:0 0 1.4em}.ps .ph img{width:100%;aspect-ratio:16/7;object-fit:cover;border:6px solid #fff;box-shadow:0 1px 0 var(--line)}
.ps .hero.banner{background:repeating-linear-gradient(180deg,#fff 0 31px,#cfe0f3 31px 32px);border-bottom:2px solid var(--line)}
.ps .hero.banner img{border:6px solid #fff;box-shadow:0 10px 24px rgba(23,63,120,.14);border-radius:0}
.ps .page.toc-layout .toc{border-left:2px solid var(--accent2)}
.ps .page.toc-layout .toc strong{font-family:var(--hf);color:#173f78}
.ps .layout{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,220px),1fr));gap:14px;margin:0 0 1.4em}
.ps .layout div{background:#fff;border:1px solid #cddcee;padding:12px 14px;border-top:3px solid var(--accent)}
.ps .layout div:nth-child(2){border-top-color:var(--accent2)}
.ps .layout strong{display:block;font-family:var(--hf);color:#173f78}
/* Footer: dark notebook cover */
.ps footer.site{background:#173f78;color:#dbe6f5;border-top:6px solid var(--accent2)}
.ps footer.site a{color:#fff}
@media(min-width:1800px){.ps{font-size:19px}.ps .hero h1{max-width:24ch}.ps .cards.gd{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(min-width:2300px){.ps{font-size:20.5px}.ps .rvs{grid-template-columns:repeat(2,minmax(0,1fr))}}