:root{--paper:#f6f4ed;--ink:#25352d;--sage:#dce6d9;--line:#d4d9ce;--muted:#536057;--white:#fff;--space:24px}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.55 -apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif}a{color:inherit;text-underline-offset:5px}a:focus-visible,button:focus-visible,video:focus-visible{outline:3px solid #52775f;outline-offset:5px}header{max-width:1100px;margin:auto;padding:28px 24px 24px;text-align:center}.brand{margin:0 0 24px;font:30px/1.1 Georgia,serif}.brand small{display:block;margin-top:6px;font:11px/1.5 -apple-system,BlinkMacSystemFont,sans-serif;letter-spacing:.18em;text-transform:uppercase}h1{font:clamp(38px,4vw,64px)/1.08 Georgia,serif;letter-spacing:-.025em;margin:0 auto 20px;max-width:1050px}.subtitle{font:22px/1.4 Georgia,serif;margin:0 0 10px}.boundary{font-size:14px;color:var(--muted);max-width:800px;margin:auto}main,footer{max-width:1510px;margin:auto;padding:0 40px}.topics{display:flex;flex-wrap:wrap;justify-content:center;gap:12px;margin:4px 0 26px}.topics a{border:1px solid #aeb9ae;border-radius:30px;min-height:48px;padding:10px 28px;text-decoration:none;font:17px/1.5 Georgia,serif}.topics a[aria-current="true"]{background:var(--sage);border-color:var(--sage)}.chapter{scroll-margin-top:24px;margin-bottom:64px}h2{font:30px/1.2 Georgia,serif;letter-spacing:-.01em;margin:0 0 20px}.chapter>h2{text-align:center}.pair{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:24px}figure{margin:0;background:var(--white);border:1px solid var(--line);border-radius:9px;overflow:hidden;min-width:0}figcaption{padding:12px 24px;border-bottom:1px solid var(--line);font-size:12px;letter-spacing:.08em;text-transform:uppercase;background:#ebece6}.capture{min-height:480px;display:flex;justify-content:center;align-items:flex-start;background:#e8e8df;padding:20px}.capture img{display:block;width:100%;height:auto;object-fit:contain}.capture.phone img{width:230px;max-width:100%;height:auto}.capture.desktop{padding:0;min-height:480px;align-items:center}.plain-site{padding:30px 40px;color:#606760;font:15px/1.5 Arial,sans-serif;min-height:480px}.plain-brand{font-size:24px;font-weight:bold;margin:0 0 20px}.plain-nav{border-block:1px solid #d8dcd6;padding:14px 0;font-size:12px}.plain-site h3{font:25px/1.2 Arial,sans-serif;margin:26px 0 16px;max-width:350px}.plain-site p{max-width:360px;margin:0 0 20px}.plain-picture{width:180px;max-width:100%;margin-bottom:20px;height:110px;overflow:hidden;background:#deded6;display:flex;align-items:center;justify-content:center;padding:12px;text-align:center;color:#677066;font-size:12px}.plain-picture img{width:360px;max-width:none;transform:translateX(-170px)}.plain-contact{display:inline-block;border:1px solid #aeb5ac;padding:6px 14px}.annotation{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:40px;align-items:start;border-top:1px solid var(--line);padding-top:20px;margin-top:24px}.annotation p{margin:0 0 10px;max-width:850px}.annotation .observed{font:23px/1.3 Georgia,serif}.annotation .check{color:var(--muted);font-size:14px}.annotation>a{max-width:250px;margin-top:4px}.js .chapter{display:none;margin-bottom:0}.js .chapter.active{display:block}.walkthrough{border-top:1px solid var(--line);margin-top:64px;padding-top:32px;display:grid;grid-template-columns:1fr 1.5fr;gap:24px;align-items:start}.walkthrough video{width:100%;background:var(--ink);border-radius:8px}.walkthrough>a{grid-column:2}footer{margin-top:48px;padding-top:24px;padding-bottom:32px;border-top:1px solid var(--line);display:flex;gap:24px;justify-content:space-between;color:var(--muted);font-size:13px}footer p{margin:0;max-width:700px}.skip{position:absolute;left:16px;top:-100px;z-index:2;background:var(--white);padding:10px}.skip:focus{top:12px}@media(min-width:1000px){.desktop-break{display:none}}@media(max-width:1000px){.annotation{grid-template-columns:1fr;gap:4px}.annotation>a{max-width:none}.topics a{padding-inline:20px}.plain-site{padding:24px}.capture{min-height:480px}}@media(max-width:700px){header{padding:24px 20px}.brand{font-size:26px;margin-bottom:24px}h1{font-size:38px}.subtitle{font-size:20px}.boundary{font-size:13px}.desktop-break{display:none}main,footer{padding-inline:20px}.topics{justify-content:flex-start;gap:8px}.topics a{padding:10px 17px;font-size:16px}.pair{grid-template-columns:1fr;gap:20px}.capture{min-height:0;padding:16px}.capture.phone img{width:250px}.capture.desktop{min-height:0;padding:0}.plain-site{min-height:0;padding:24px}.plain-site h3{font-size:24px;margin-top:20px}.plain-picture{float:right;width:120px;margin:0 0 16px 16px;height:85px}.plain-site:after{content:"";display:block;clear:both}.annotation .observed{font-size:24px}.walkthrough{grid-template-columns:1fr;margin-top:40px}.walkthrough>a{grid-column:auto}footer{display:block}footer a{display:block;margin-top:16px}h2{font-size:28px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto}}@media print{.topics,.walkthrough{display:none}.js .chapter{display:block;break-inside:avoid;margin-bottom:32px}a{overflow-wrap:anywhere}}
/* Proof workbench optical exception: on narrow screens show the actual website
   first; the clearly labelled schematic follows it. Source order stays before /
   current without CSS, and both figures remain readable by assistive tools. */
@media(max-width:700px){.pair .current{grid-row:1}.pair .before{grid-row:2}.plain-site{padding:16px;font-size:13px;line-height:1.5}.plain-site h3{font-size:20px;margin:0 0 10px}.plain-site p{margin-bottom:0}.plain-brand,.plain-nav,.plain-picture,.plain-contact,.plain-site>p:last-of-type{display:none}header{padding-top:20px;padding-bottom:20px}.brand{font-size:24px;margin-bottom:16px}h1{font-size:34px;margin-bottom:14px}.subtitle{font-size:18px;margin-bottom:8px}.boundary{font-size:12px}.topics{margin-bottom:20px}.chapter>h2{font-size:26px;margin-bottom:16px}}

/* V4 implemented review corrections (rendered acceptance pending): actual image proportions, no fixed dead field,
   current-first single-column tablet, readable phone image scale. */
.chapter>h2{position:absolute;width:1px;height:1px;margin:0;padding:0;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
.capture.desktop{min-height:0;align-items:flex-start;padding:0;aspect-ratio:auto}
.capture.desktop img{height:auto;width:100%}
.capture.phone{min-height:0;padding:16px;align-items:flex-start}
.capture.phone img{width:min(100%,390px);max-width:100%;height:auto;border:1px solid var(--line);border-radius:6px}
.plain-site{min-height:0;padding:20px}
.plain-brand{font-size:22px;margin-bottom:12px}
.plain-nav{padding:8px 0}
.plain-site h3{font-size:24px;max-width:none;margin:18px 0 12px}
.plain-site p{max-width:none;font-size:14px;margin-bottom:12px}
.plain-picture{height:56px;width:140px;margin-bottom:12px}
.plain-contact,.plain-site>p:last-of-type{display:none}
.scope{font-size:13px;line-height:1.5;margin:0;padding:12px 20px;border-bottom:1px solid var(--line);background:var(--sage)}
.header-actions{display:flex;justify-content:center;flex-wrap:wrap;gap:12px 24px;margin-top:14px;font-size:14px}
@media(max-width:1000px){.pair{grid-template-columns:1fr}.pair .current{grid-row:1}.pair .before{grid-row:2}.capture.desktop{min-height:0}.plain-site{padding:16px}.plain-brand,.plain-nav,.plain-picture{display:none}.plain-site h3{font-size:20px;margin:0 0 10px}.plain-site p{margin:0}.capture.phone img{width:min(100%,390px)}}

.capture picture{display:block;width:100%}
@media(max-width:1000px){.capture.responsive-project picture{width:min(100%,390px)}.capture.responsive-project{padding:16px}.capture.responsive-project img{width:100%;height:auto}}