/* Tokens from kaas.team src/styles/base.css: ink on paper, one light theme. Every custom property lives in this
   one :root block, because the EPUB copy resolves them to values and fails on any token left unresolved. */
@font-face{font-family:Geist;src:url(geist.woff2) format("woff2");font-weight:400 600;font-style:normal}
@font-face{font-family:"Geist Mono";src:url(geist-mono.woff2) format("woff2");font-weight:400;font-style:normal}
:root{--page:#f7f7f7;--surface:#fff;--panel:#fafafa;--ink:#171717;--ink-2:#3d3d3d;--muted:#5c5c5c;--line:#e5e5e5;--rule:#d4d4d4;
--focus:#2563eb;--on-focus:#fff;--fail:#b4233a;--fail-bg:#fcf0f0;--pass:#1f7a45;--pass-bg:#dff9e9;--wait-bg:#fdf6d3;
--sans:Geist,Inter,system-ui,-apple-system,"Segoe UI",sans-serif;--mono:"Geist Mono",ui-monospace,"SF Mono",Menlo,Consolas,monospace;
--code-bg:#fff;--code-bar:#fafafa;--code-fg:#171717;--code-num:#737373;--hl-bg:#eef5ff;--hl-edge:#0b63d6;--add-edge:#1f7a45;
--k:#c0156b;--s:#0f7a33;--c:#6b6b6b;--n:#0b5cc4;--f:#7323b8;--b:#9a4a00}
*{box-sizing:border-box}
html{background:var(--page);scroll-padding-top:72px}
body{margin:0;background:var(--page);color:var(--ink);font:17px/1.6 var(--sans)}
a{color:var(--focus)}
:focus-visible{outline:2px solid var(--focus);outline-offset:2px}
:not(pre)>code{font:.86em var(--mono);background:var(--panel);border:1px solid var(--line);border-radius:4px;padding:0 4px}
h1{font-size:44px;line-height:1.1;font-weight:400;letter-spacing:-.02em;margin:0 0 16px}
h2{font-size:28px;line-height:1.2;font-weight:500;letter-spacing:-.01em;margin:0 0 14px}
h3{font-size:18px;line-height:1.3;font-weight:600;margin:0 0 8px}
p,ul,ol,table{margin:0 0 14px}
li{margin:0 0 6px}

.top{position:sticky;top:0;z-index:5;display:flex;flex-wrap:wrap;gap:8px 16px;align-items:center;min-height:56px;padding:8px 24px;
  background:var(--page);border-bottom:1px solid var(--line);font-size:14px}
.top .brand{margin-right:auto;color:var(--ink);font-weight:600;text-decoration:none}
.top a{color:var(--muted);text-decoration:none}.top a:hover{color:var(--ink)}
.find{position:relative}
.find input{width:220px;height:34px;padding:0 10px;border:1px solid var(--line);border-radius:6px;background:var(--surface);font:inherit;color:var(--ink)}
.find ol{position:absolute;right:0;top:40px;width:360px;max-height:60vh;overflow:auto;list-style:none;margin:0;padding:6px;
  background:var(--surface);border:1px solid var(--line);border-radius:6px}
.find ol:empty{display:none}
.find li{margin:0}.find li a{display:block;padding:6px 8px;border-radius:4px;color:var(--ink)}
.find li a:hover,.find li a:focus{background:var(--panel)}.find li span{display:block;font-size:12px;color:var(--muted)}

.bkw{display:grid;grid-template-columns:240px minmax(0,1fr);max-width:1190px;margin:0 auto;border-left:1px solid var(--line);border-right:1px solid var(--line)}
.toc{position:sticky;top:56px;align-self:start;max-height:calc(100vh - 56px);overflow:auto;padding:28px 20px;border-right:1px solid var(--line);font-size:14px}
.toc h2{font-size:13px;font-weight:600;color:var(--muted);margin:16px 0 4px}
.toc ol{list-style:none;padding:0;margin:0}
.toc li{margin:0}
.toc a{display:block;padding:5px 0;line-height:1.35;color:var(--muted);text-decoration:none}
.toc a:hover,.toc a[aria-current]{color:var(--ink)}
.toc a[aria-current]{font-weight:600}
.bbody{min-width:0;padding:48px 56px 80px;background:var(--surface)}
.bbody>*{max-width:760px}
.kicker{font-size:15px;color:var(--muted);margin:0 0 12px}
.claim{font-size:22px;line-height:1.35;letter-spacing:-.01em;color:var(--ink);margin:0 0 18px}
.lede{font-size:19px;color:var(--ink-2)}
.stage{display:flex;gap:12px;align-items:baseline;margin:56px 0 0;padding:0 0 12px;border-bottom:2px solid var(--ink)}
.stage b{font-size:20px;font-weight:600;letter-spacing:-.01em}.stage span{color:var(--muted)}
.step{padding:36px 0 0}
.step+.step{border-top:1px solid var(--line);margin-top:36px}
.stage+.step{padding-top:24px}
table{border-collapse:collapse;font-size:15px}
th,td{text-align:left;vertical-align:top;padding:6px 14px 6px 0;border-bottom:1px solid var(--line)}
pre{background:var(--code-bg);border:1px solid var(--line);border-radius:8px;padding:14px 16px;overflow:auto;font:13px/20px var(--mono);color:var(--code-fg)}
pre code{font:inherit;background:none;border:0;padding:0}
.fig{margin:20px 0}
.note{padding:10px 14px;background:var(--wait-bg);border-radius:6px;font-size:15px}

.predict,.quiz .q{margin:18px 0;padding:14px 16px;border:1px solid var(--line);border-radius:6px;background:var(--panel)}
.predict .ask,.quiz .ask{font-weight:600;margin:0 0 8px}
.opts{list-style:none;padding:0;margin:0 0 8px}
.opts li{margin:0 0 4px}.opts b{display:inline-block;width:1.6em}
details summary{cursor:pointer;font-size:15px;font-weight:500;color:var(--focus)}
details p,details li{margin:8px 0 0}
.right{color:var(--pass);font-weight:600}
.wrong{color:var(--fail);font-weight:600}
.run{list-style:none;padding:0;margin:20px 0 10px;position:relative}
.run::before{content:"";position:absolute;left:5px;top:12px;bottom:12px;width:1px;background:var(--rule)}
.run>li{position:relative;display:grid;grid-template-columns:6em minmax(0,1fr);column-gap:8px;margin:0;padding:8px 0 8px 26px;font-size:15px;line-height:1.5}
.run>li>details{grid-column:2}
.run>li::before{content:"";position:absolute;left:0;top:14px;width:11px;height:11px;border-radius:50%;background:var(--surface);border:2px solid var(--muted)}
.run>li>b{padding-top:2px;font-size:13px;font-weight:600;color:var(--ink-2)}
.run>li.r-reply::before{background:var(--ink);border-color:var(--ink)}
.run>li[class*="r-stopped"]::before,.run>li[class*="r-refused"]::before{border-color:var(--fail)}
.run>li[class*="r-stopped"]>b{color:var(--fail)}
.run details{margin:4px 0 0}
.run summary{font-size:13px;font-weight:500;color:var(--muted);list-style:none}
.run summary::-webkit-details-marker{display:none}
.run summary::before{content:"";display:inline-block;width:6px;height:6px;margin:0 8px 2px 1px;border:solid currentColor;border-width:0 1.5px 1.5px 0;transform:rotate(-45deg);transition:transform .15s}
.run details[open]>summary::before{transform:rotate(45deg)}
.run summary:hover{color:var(--ink)}
.run pre{margin:8px 0 0;font-size:12.5px;line-height:19px;max-height:22rem}
.outcome{margin:0 0 14px;padding:10px 14px;border-radius:6px;font-weight:600;background:var(--panel)}
.outcome.good{background:var(--pass-bg);color:var(--pass)}.outcome.bad{background:var(--fail-bg);color:var(--fail)}
.terms dt{font-weight:600;margin:10px 0 2px}.terms dd{margin:0 0 6px;color:var(--ink-2)}

.code{position:relative;margin:4px 0;background:var(--code-bg);border:1px solid var(--line);border-radius:8px;overflow:hidden;font:13px/20px var(--mono)}
.code .file{display:flex;align-items:center;gap:12px;height:40px;padding:0 8px 0 14px;background:var(--code-bar);border-bottom:1px solid var(--line);color:var(--ink-2);font:13px var(--mono)}
.code .file>span:first-child{display:flex;align-items:center;gap:8px;margin-right:auto;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.code .file>span:first-child::before{content:"";flex:none;width:14px;height:14px;background:var(--muted);
  -webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none' stroke='black' stroke-width='1.5'%3E%3Cpath d='M9 1.75H3.75v12.5h8.5V5L9 1.75Z'/%3E%3Cpath d='M9 1.75V5h3.25'/%3E%3C/svg%3E") center/contain no-repeat;
  mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none' stroke='black' stroke-width='1.5'%3E%3Cpath d='M9 1.75H3.75v12.5h8.5V5L9 1.75Z'/%3E%3Cpath d='M9 1.75V5h3.25'/%3E%3C/svg%3E") center/contain no-repeat}
.code.block .file>span:first-child::before{
  -webkit-mask-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none' stroke='black' stroke-width='1.5'%3E%3Cpath d='m3 4.5 3.5 3.5L3 11.5M8.5 12H13'/%3E%3C/svg%3E");
  mask-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none' stroke='black' stroke-width='1.5'%3E%3Cpath d='m3 4.5 3.5 3.5L3 11.5M8.5 12H13'/%3E%3C/svg%3E")}
.code .file .note{padding:0;background:none;color:var(--code-num);font:13px var(--sans);white-space:nowrap}
.copy{display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;padding:0;border:0;border-radius:6px;background:none;color:var(--muted);cursor:pointer}
.copy:hover{background:var(--line);color:var(--ink)}
.copy svg{width:15px;height:15px}
.code .src{overflow-x:auto;padding:12px 0}
.code pre{margin:0;border:0;border-radius:0}
.code .ln{display:block;padding:0 16px 0 0;white-space:pre;color:var(--code-fg);box-shadow:inset 2px 0 transparent}
.code .ln i{display:inline-block;width:4em;padding-right:1.4em;text-align:right;color:var(--code-num);font-style:normal;user-select:none}
.code .ln.hl{background:var(--hl-bg);box-shadow:inset 2px 0 var(--hl-edge)}
.code .ln.add{background:var(--pass-bg);box-shadow:inset 2px 0 var(--add-edge)}
.code .ln.add i::before{content:"+";float:left;margin-left:.5em;color:var(--add-edge)}
.code .ln.gap{margin:6px 0;padding:4px 16px 4px 0;color:var(--code-num);font:13px var(--sans);background:var(--code-bar);border-block:1px dashed var(--line)}
.code .ln.gap i{visibility:hidden}
.t-k{color:var(--k)}.t-s{color:var(--s)}.t-c{color:var(--c)}.t-n{color:var(--n)}.t-f{color:var(--f)}.t-b{color:var(--b)}
/* Geist Mono joins -> and == into glyphs, and the font shorthand resets it, so this comes last; code must show what was typed. */
code,pre,.code,.code *{font-variant-ligatures:none;font-feature-settings:"liga" 0,"calt" 0}

.draw{width:100%;height:auto;display:block;background:var(--surface);border:1px solid var(--line);border-radius:6px;padding:8px}
.draw.tall{display:none}
.d-box{fill:var(--page);stroke:var(--ink-2);stroke-width:2}.d-box.d-money{stroke:var(--fail);stroke-width:3}
.d-guard{fill:var(--ink)}.d-guard-text{fill:var(--surface);font:600 24px var(--sans)}.d-guard-sub{fill:var(--surface)}
.d-text{fill:var(--ink);font:19px var(--sans)}.d-sub{fill:var(--muted);font:18px var(--sans)}.d-fail{fill:var(--fail);font-weight:600}
.d-label{paint-order:stroke;stroke:var(--surface);stroke-width:8px;stroke-linejoin:round}
.d-arrow{stroke:var(--ink-2);stroke-width:2.5;fill:none}.d-deny{stroke:var(--fail);stroke-width:3.5}.d-dash{stroke-dasharray:6 5}
.d-head{fill:var(--ink-2)}.d-head-deny{fill:var(--fail)}.d-lane{stroke:var(--muted);stroke-width:1.5;stroke-dasharray:4 6}

.pager{display:flex;flex-wrap:wrap;gap:12px;margin-top:56px;padding-top:24px;border-top:1px solid var(--line)}
.pager a{flex:1 1 16rem;padding:14px 18px;border:1px solid var(--line);border-radius:8px;color:var(--ink);text-decoration:none;font-weight:500;font-size:17px}
.pager a span{display:block;font-size:13px;font-weight:400;color:var(--muted)}
.pager a:hover{border-color:var(--ink)}.pager .next{text-align:right}
.foot{max-width:1190px;margin:0 auto;padding:24px;border:1px solid var(--line);border-bottom:0;font-size:14px;color:var(--muted)}

.cover{padding:8px 0 40px}
.cover h1{font-size:56px}
.btns{display:flex;flex-wrap:wrap;gap:8px;margin:20px 0 0}
.btn{display:inline-flex;align-items:center;height:36px;padding:0 14px;border:1px solid var(--line);border-radius:6px;background:var(--surface);
  color:var(--ink);font-size:14px;font-weight:500;text-decoration:none}
.btn.dark{background:var(--ink);border-color:var(--ink);color:var(--surface)}
.part{padding:40px 0 0}
.part h2{padding-bottom:12px;border-bottom:2px solid var(--ink);margin:0}
.lessons{list-style:none;padding:0;margin:0}
.lessons>li{margin:0;border-bottom:1px solid var(--line)}
.lessons a{display:grid;grid-template-columns:2.5rem minmax(0,1fr);column-gap:8px;padding:14px 8px 14px 0;color:var(--ink);text-decoration:none}
.lessons a:hover{background:var(--panel)}
.lessons .num{grid-row:span 2;padding-left:8px;color:var(--muted);font:15px/1.6 var(--mono)}
.lessons .nm{font-size:18px;font-weight:600;line-height:1.6}
.lessons .cl{color:var(--muted);font-size:15px;line-height:1.45}
.lessons a:hover .nm{text-decoration:underline;text-underline-offset:3px}

@media screen and (max-width:860px){
  .bkw{grid-template-columns:minmax(0,1fr)}.toc{display:none}
  .bbody{padding:32px 16px 64px}
  h1,.cover h1{font-size:34px}
  .draw.wide{display:none}.draw.tall{display:block;max-width:420px;margin:0 auto}
  .find input{width:150px}.find ol{width:min(360px,calc(100vw - 32px))}
}
@media print{
  @page{size:A4;margin:16mm 14mm}
  html,body,.bbody{background:#fff}
  body{font-size:11pt}
  .top,.toc,.pager,.foot,.find{display:none}
  .bkw{display:block;border:0;max-width:none}
  .bbody{padding:0}.bbody>*{max-width:none}
  .lesson{break-before:page}
  .code,.draw,.predict,.quiz .q,table{break-inside:avoid}
  .code .ln{white-space:pre-wrap}
  details>*{display:block}
  h2,h3,.stage{break-after:avoid}
  a{color:inherit;text-decoration:none}
}