/* The Python guide's own stylesheet, lifted out of the source by
   _src/build-python-guide.py so it loads under style-src 'self'.
   Do not edit by hand. */
@font-face{font-family:'Noto Serif';src:url('/assets/fonts/noto-serif-latin.woff2') format('woff2');font-weight:400 700;font-style:normal;font-display:swap}
@font-face{font-family:'Archivo';src:url('/assets/fonts/archivo-latin.woff2') format('woff2');font-weight:600 900;font-style:normal;font-display:swap}
@font-face{font-family:'Inter';src:url('/assets/fonts/inter-latin.woff2') format('woff2');font-weight:400 700;font-style:normal;font-display:swap}

:root{
 --ink0:#1A2123; --ink1:#2A3335; --ink2:#222B2D;
 --paper1:#F4EEE5; --sand1:#DCC9B2; --stone:#8C8175; --slate:#4A5254;
 --petrol:#2E5A5E; --petroll:#6E9BA0; --seafoam:#A9C9C9; --sky:#C3D7DC;
 --gold:#D9A25F; --clay:#D18F6E;
 --line:rgba(244,238,229,.12);
 --serif:var(--font-editorial);
 --sans:var(--font-body);
 --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:78px;
 -webkit-text-size-adjust:100%;text-size-adjust:100%}
body{margin:0;overflow-x:hidden;background:var(--ink0);color:var(--sand1);
 font-family:var(--sans);font-size:17px;line-height:1.62;
 -webkit-font-smoothing:antialiased}
.shell{max-width:1180px;margin:0 auto;padding:0 26px 110px;
 display:grid;grid-template-columns:1fr;gap:0}

/* ---------- masthead ---------- */
.top{position:sticky;top:0;z-index:20;
 padding:14px 0;margin:0 -26px;padding-left:26px;padding-right:26px;
 display:flex;align-items:center;justify-content:space-between;gap:16px;
 flex-wrap:wrap;background:rgba(26,33,35,.94);
 -webkit-backdrop-filter:blur(9px);backdrop-filter:blur(9px);
 border-bottom:1px solid var(--line)}
.brand{line-height:0}
.brand .wm{height:30px;width:auto}


header.hero{padding:34px 0 10px}
.kicker{font-family:var(--mono);font-size:11.5px;letter-spacing:.16em;
 text-transform:uppercase;color:var(--stone);margin:0 0 16px}
h1{font-family:var(--serif);font-weight:400;
 font-size:clamp(34px,6vw,60px);line-height:1.06;letter-spacing:-.005em;
 margin:0 0 26px;color:var(--paper1);text-wrap:balance;max-width:19ch}
h1 .a{color:var(--seafoam)}
img.dm{max-width:min(430px,100%);width:100%;height:auto;display:block;
 margin:0 0 26px;border-radius:8px}
.lead{font-size:20px;line-height:1.55;color:var(--sky);max-width:60ch;margin:0 0 30px;
 padding-bottom:30px;border-bottom:1px solid var(--line)}

/* ---------- two-column body ---------- */
.body{display:grid;grid-template-columns:1fr;gap:0}
@media(min-width:1000px){
 .body{grid-template-columns:212px minmax(0,1fr);gap:56px;align-items:start}
 nav.toc{position:sticky;top:40px;padding-top:44px}
}
nav.toc{padding:26px 0 6px}
nav.toc .lab{font-family:var(--mono);font-size:10.5px;letter-spacing:.15em;
 text-transform:uppercase;color:var(--stone)}
nav.toc ol{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:1px}
nav.toc a{display:grid;grid-template-columns:22px 1fr;gap:8px;
 text-decoration:none;color:var(--stone);font-size:13.5px;line-height:1.35;
 padding:6px 0;border-bottom:1px solid transparent}
nav.toc a:hover{color:var(--paper1)}
nav.toc .tn{font-family:var(--mono);font-size:11.5px;color:var(--petroll);padding-top:1px}
nav.toc li.sub a{color:var(--slate);font-size:12.5px}
nav.toc li.sub a:hover{color:var(--sand1)}

main{padding-top:34px;max-width:900px}
h2{max-width:24ch;font-family:var(--serif);font-weight:400;font-size:clamp(25px,3.4vw,33px);
 line-height:1.18;color:var(--paper1);margin:52px 0 14px;
 padding-top:22px;border-top:1px solid var(--line);
 scroll-margin-top:24px;text-wrap:balance}
h2 .n{color:var(--seafoam);font-family:var(--mono);font-size:.52em;
 vertical-align:.42em;margin-right:.55em;letter-spacing:.02em}
main > h1{max-width:20ch;font-size:clamp(30px,5vw,46px);margin:74px 0 8px;
 padding-top:30px;border-top:1px solid var(--line);scroll-margin-top:24px}
p{margin:0 0 15px;max-width:68ch}
b,strong{color:var(--paper1);font-weight:600}
i,em{font-style:italic}
a{color:var(--petroll);text-decoration:none;
 border-bottom:1px solid rgba(110,155,160,.35);transition:border-color .15s,color .15s}
a:hover{color:var(--seafoam);border-bottom-color:var(--seafoam)}
a:focus-visible{outline:2px solid var(--seafoam);outline-offset:3px;border-radius:2px}
ul{margin:0 0 16px;padding-left:20px;max-width:68ch}
li{margin-bottom:7px}
li::marker{color:var(--petrol)}

.note{background:var(--ink1);border-left:3px solid var(--gold);
 padding:15px 18px;margin:20px 0;font-size:15.5px;line-height:1.55;
 border-radius:0 5px 5px 0;max-width:68ch}
.note p:last-child{margin-bottom:0}

/* numbered path */
.path{background:var(--ink1);border-radius:6px;padding:6px 20px;margin:20px 0;max-width:68ch}
.path > div{display:grid;grid-template-columns:24px 1fr;gap:14px;
 padding:13px 0;border-bottom:1px solid rgba(244,238,229,.08);align-items:start}
.path > div:last-child{border-bottom:none}
.path .i{font-family:var(--mono);font-size:12.5px;color:var(--seafoam);padding-top:3px}
.path .w{color:var(--paper1);font-weight:600;font-size:15.5px;display:block}
.path .t{grid-column:2;color:var(--stone);font-size:14.5px;display:block;margin-top:3px;line-height:1.5}
@media(min-width:760px){
 .path > div{grid-template-columns:24px 15rem 1fr;gap:16px}
 .path .t{grid-column:3;margin-top:0}
}

/* lettered steps */
.step{display:grid;grid-template-columns:26px 1fr;gap:14px;margin-bottom:16px;max-width:68ch}
.step .num{width:26px;height:26px;border-radius:6px;background:var(--gold);
 color:var(--ink0);font-weight:700;font-size:14px;
 display:flex;align-items:center;justify-content:center;margin-top:2px}

/* the slide trio */
.two{display:grid;grid-template-columns:1fr;gap:8px;margin:22px 0}
@media(min-width:1180px){ .two{grid-template-columns:1fr}}
.two .r{margin-top:20px}
.figtitle{font-family:var(--serif);font-weight:400;font-size:23px;
 color:var(--paper1);margin:0 0 16px}
header.hero{max-width:900px}
.two .r img{max-width:760px;width:100%;height:auto;display:block;border-radius:5px;
 border:1px solid var(--line);margin-bottom:8px}
.cap{font-family:var(--mono);font-size:12px;color:var(--stone);
 margin:0 0 26px;line-height:1.5}

/* tables -> cards on small screens */
.tw{margin:20px 0 34px}
table{border-collapse:collapse;width:100%;font-size:15px}
thead th,tr th{text-align:left;font-family:var(--mono);font-size:10.5px;
 letter-spacing:.13em;text-transform:uppercase;color:var(--slate);
 border-bottom:1px solid var(--petrol);padding:0 14px 9px 0;font-weight:500}
td{padding:14px 14px 14px 0;border-bottom:1px solid rgba(244,238,229,.08);
 vertical-align:top;color:var(--sand1);line-height:1.5}
td.name{color:var(--paper1);font-weight:600;width:19%}
td.url{font-family:var(--mono);font-size:12.5px;overflow-wrap:anywhere;width:29%}
td.url a{border-bottom-color:transparent}
td.url a:hover{border-bottom-color:var(--seafoam)}
.free,.paid{font-family:var(--mono);font-size:11px;letter-spacing:.05em;
 text-transform:uppercase;white-space:nowrap;font-weight:500}
.free{color:var(--seafoam)} .paid{color:var(--clay)}
@media(max-width:999px){
 .top{-webkit-backdrop-filter:none;backdrop-filter:none;background:var(--ink0)}
}
@media(max-width:719px){
 table,tbody,tr,td{display:block;width:100%}
 tr:first-child{display:none}
 tr{border:1px solid var(--line);border-radius:6px;padding:14px 16px;margin-bottom:12px;
    background:var(--ink2)}
 td{border:none;padding:2px 0}
 td.name{font-size:17px;margin-bottom:5px;width:auto}
 td.url{width:auto;margin-top:7px}
 .free,.paid{display:inline-block;margin-top:8px}
 td.url a{display:inline-block;padding:5px 0}
 .contact a{padding:4px 0}
}

footer{margin-top:64px;padding-top:24px;border-top:1px solid var(--line);
 font-size:13.5px;line-height:1.6;color:var(--stone);max-width:68ch}
.acts{display:flex;gap:10px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:8px;
 font-family:var(--sans);font-size:14px;font-weight:500;
 padding:9px 15px;border-radius:6px;cursor:pointer;
 text-decoration:none;border:1px solid var(--petrol);
 background:transparent;color:var(--seafoam);
 transition:background .15s,border-color .15s,color .15s;
 -webkit-tap-highlight-color:transparent}
.btn:hover{background:rgba(46,90,94,.22);border-color:var(--petroll);color:var(--sky)}
.btn:focus-visible{outline:2px solid var(--seafoam);outline-offset:2px}
.btn.primary{background:var(--petrol);color:var(--paper1);border-color:var(--petrol)}
.btn.primary:hover{background:var(--petroll);color:var(--ink0)}
.btn svg{width:15px;height:15px;flex:0 0 auto;stroke:currentColor;
 stroke-width:1.9;fill:none;stroke-linecap:round;stroke-linejoin:round}
.btn .ok{display:none}
.btn.done .ok{display:inline} .btn.done .idle{display:none}
.contact{display:flex;align-items:center;gap:11px 28px;flex-wrap:wrap;
 margin:0 0 20px;font-family:var(--mono);font-size:12.5px;letter-spacing:.02em;
 color:var(--stone)}
.contact a{display:inline-flex;align-items:center;gap:7px;
 color:var(--petroll);text-decoration:none;border-bottom:none;
 transition:color .15s}
.contact a:hover{color:var(--seafoam)}
.contact svg{width:15px;height:15px;flex:0 0 auto;fill:none;stroke:currentColor;
 stroke-width:5.6;vector-effect:non-scaling-stroke}
.contact .sep{color:#3A4547}
@media(max-width:520px){.contact{gap:10px 20px;font-size:12px}}
.endbar{margin-top:52px;padding-top:26px;border-top:1px solid var(--line)}
.endbar .acts{justify-content:flex-start}

/* collapsible contents */
nav.toc details{border:1px solid var(--line);border-radius:6px;overflow:hidden}
nav.toc summary{list-style:none;cursor:pointer;display:flex;align-items:center;
 justify-content:space-between;padding:13px 15px;background:var(--ink2)}
nav.toc summary::-webkit-details-marker{display:none}
nav.toc .chev{width:8px;height:8px;border-right:1.6px solid var(--stone);
 border-bottom:1.6px solid var(--stone);transform:rotate(45deg);
 transition:transform .18s;margin-top:-3px}
nav.toc details[open] .chev{transform:rotate(-135deg);margin-top:3px}
nav.toc details[open] ol{padding:6px 15px 12px}
/* ---------- lightbox for the dense slides ---------- */
img.zoomable{cursor:zoom-in}
.zh{color:var(--petroll)}
.lbx{position:fixed;inset:0;z-index:100;display:none;
 background:#12181A;overflow:auto;-webkit-overflow-scrolling:touch;
 padding:58px 12px 28px;text-align:center}
.lbx.on{display:block}
.lbx img{width:100%;max-width:1100px;height:auto;border-radius:5px;
 border:1px solid var(--line);cursor:zoom-in}
.lbx.zoom{text-align:left}
.lbx.zoom img{width:240%;max-width:none;cursor:zoom-out}
.lbx .lbcap{position:fixed;left:0;right:0;top:0;z-index:1;
 padding:15px 62px 13px 16px;background:#12181A;
 border-bottom:1px solid var(--line);text-align:left;
 font-family:var(--mono);font-size:11.5px;line-height:1.4;color:var(--stone)}
.lbx .x{position:fixed;top:8px;right:10px;z-index:2;
 width:44px;height:44px;padding:0;border-radius:50%;
 border:1px solid var(--petrol);background:rgba(26,33,35,.94);
 color:var(--seafoam);font:400 22px/1 var(--sans);cursor:pointer;
 display:flex;align-items:center;justify-content:center;
 -webkit-tap-highlight-color:transparent}
.lbx .x:hover{background:rgba(46,90,94,.4)}

/* ---------- phones ---------- */
@media(max-width:620px){
 body{font-size:16.5px;line-height:1.6}
 .shell{padding:0 17px 76px}
 .top{margin:0 -17px;padding:11px 17px}
 .brand .wm{height:26px}
 header.hero{padding:24px 0 6px}
 .kicker{margin-bottom:13px}
 h1{margin-bottom:20px;max-width:none}
 img.dm{margin-bottom:22px}
 .lead{font-size:18px;margin-bottom:24px;padding-bottom:24px}
 h2{margin:38px 0 12px;padding-top:20px;max-width:none}
 main > h1{max-width:none}
 main{padding-top:22px}
 main > h1{margin:50px 0 6px;padding-top:26px}
 nav.toc{padding:20px 0 4px}
 nav.toc summary{padding:15px 15px}
 nav.toc a{padding:10px 0}
 nav.toc li.sub a{font-size:13px}
 .path{padding:4px 16px}
 .path > div{padding:12px 0}
 .note{padding:14px 15px;margin:18px 0}
 .step{gap:12px}
 .figtitle{font-size:21px;margin-bottom:13px}
 .two{margin:18px 0}
 .two .r img{border-radius:4px}
 .cap{margin-bottom:22px}
 .tw{margin:18px 0 28px}
 tr{padding:13px 15px}
 footer{margin-top:46px}
 .endbar{margin-top:40px}
 .lbx{padding:56px 8px 24px}
}
@media(max-width:380px){
 .shell{padding:0 14px 70px}
 .top{margin:0 -14px;padding:10px 14px}
 body{font-size:16px}
 .lead{font-size:17px}
}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}
@media(min-width:1000px){
 nav.toc details{border:none;border-radius:0;overflow:visible}
 nav.toc details > ol{display:flex;padding:0}
 nav.toc details[open] ol{padding:0}
 nav.toc summary{padding:0 0 14px;background:transparent;cursor:default;
  pointer-events:none}
 nav.toc .chev{display:none}
}

/* The source's own top bar is the wordmark and nothing else, and the site
   header above it already carries that. */
.shell > .top{display:none}

/* The label role. The source sets these in monospace; on this site a small
   caps label is Archivo. What stays monospace below is what is actually
   code: the section numbers, the paths, and the URLs in the reading list. */
.kicker,nav.toc .lab,.cap,thead th,tr th,.free,.paid,.contact{
  font-family:var(--font-display)}

:root[data-theme='light']{
  --ink0:#FBF7F1; --ink1:#F4EEE5; --ink2:#E9E0D3;
  --paper1:#1A2123; --sand1:#2A3335; --stone:#5F594E; --slate:#8C8175;
  --petrol:#2E5A5E; --petroll:#2E5A5E; --seafoam:#2E5A5E; --sky:#4E7C82;
  --gold:#8A6220; --clay:#8F5641;
  --line:rgba(26,33,35,.14);
}

/* September 27 2026, added by hand in the web root (see _CLAUDE_HANDOFF.md):
   the read-later link under the contents, and the newsletter block at the end. */
nav.toc a.toc-mail{display:inline-flex;grid-template-columns:none;width:auto;flex-wrap:wrap;gap:4px 6px;margin-top:14px;padding:8px 12px;
  border:1px solid var(--line);border-radius:999px;font-size:12.5px;line-height:1.3;
  text-decoration:none;color:var(--paper1)}
nav.toc a.toc-mail .q{color:var(--stone)}
nav.toc a.toc-mail .a{color:var(--gold);font-weight:600}
nav.toc a.toc-mail:hover{border-color:var(--gold)}
nav.toc a.toc-mail:focus-visible{outline:2px solid var(--seafoam);outline-offset:2px}
.stay{margin-top:56px;padding:28px;border:1px solid var(--line);border-radius:8px;background:var(--ink2)}
.stay h2{margin-top:6px}
.stay p:last-child{margin-bottom:0}
@media (max-width:999px){nav.toc a.toc-mail{margin:10px 0 4px}}