/* Regional anaesthesia app: shared styles for the engine pages (truncal/, head-neck/, lower-limb/): app bar, components,
   block chapters, scan viewer, coverage map. Level control and tier hiding: levels.css (imported below).
   Design: DESIGN.md (paper, ink, one wine accent, square, hairlines, light only). Prefix: tb-.
   Teaching colours (nerves yellow, arteries red, veins blue, LA blue, ultrasound greys) are clinical codes. */

@import url('levels.css?v=20261015');
@import url('appnav.css?v=20261018'); /* desktop frame and rail, bar auto-hide, view transitions (shared with spinal/, brachial-plexus/, the landings) */
@font-face{font-family:'NTF Serif';src:url('../../../fonts/fraunces-roman.woff2') format('woff2');font-weight:300 600;font-display:swap}
@font-face{font-family:'NTF Serif';src:url('../../../fonts/fraunces-italic.woff2') format('woff2');font-style:italic;font-weight:300 600;font-display:swap}
@font-face{font-family:'NTF Sans';src:url('../../../fonts/inter.woff2') format('woff2');font-weight:300 700;font-display:swap}
@font-face{font-family:'NTF Mono';src:url('../../../fonts/jetbrains-mono.woff2') format('woff2');font-weight:400 500;font-display:swap}

/* ------------------------------------------------------------------ tokens */
body.tb-app{
  --tb-paper:#f7f5ef;--tb-inset:#eee9df;--tb-panel:#eeece5;--tb-hover:#e9e5dc;--tb-blush:#e8ded7;
  --tb-ink:#272722;--tb-ink-soft:#504e47;--tb-muted:#55534d;--tb-wine:#633d3c;--tb-wine-hover:#4b2e2d;--tb-ivory:#fffaf0;
  --tb-line:#d7d2c8;--tb-line-strong:#8f8574;--tb-control:#827b6d;
  --tb-danger:#a12a1c;--tb-danger-bg:#fbebe7;--tb-warn:#7a4f00;--tb-warn-bg:#fbf1db;
  --tb-la:#2c74b3;--tb-la-dark:#1d4f7c;--tb-la-bg:#e3eef7;
  --tb-serif:'NTF Serif','Fraunces',Georgia,serif;--tb-sans:'NTF Sans',Inter,Arial,sans-serif;--tb-mono:'NTF Mono','JetBrains Mono',ui-monospace,Menlo,monospace;
  --tb-header-h:0px; /* the site header scrolls away inside the app (one sticky bar); kept for older page CSS */
  margin:0;background:var(--tb-paper);color:var(--tb-ink);font:17px/1.65 var(--tb-sans);
  -webkit-text-size-adjust:100%;text-size-adjust:100%;overflow-x:hidden;
}
/* --ra-bar: height of the one sticky app bar. Deep-link targets land just below it. */
:root:has(body.tb-app){--ra-bar:56px}
/* Deep-link targets land 8px below the bar. Only scroll-margin is used: an html scroll-padding as well would add up
   and land targets a whole bar height too low. */
html:has(body.tb-app){color-scheme:light;scroll-padding-top:0;background:#f7f5ef}
.tb-app :is(main [id],.tb-chapter){scroll-margin-top:calc(var(--ra-bar,56px) + 8px)}
/* One sticky bar inside app pages: the site header scrolls away with the page (scoped to app pages only). */
body:is(.tb-app,.ra-app) .ntf-header{position:relative;z-index:60} /* scrolls away (only the app bar sticks); relative + z-index keep its phone menu above the bar and the page */

/* ------------------------------------------------------------------ base */
.tb-app *,.tb-app *::before,.tb-app *::after{box-sizing:border-box}
.tb-app :is(a,button,summary,select,input,textarea,[tabindex]):focus-visible{outline:2px solid var(--tb-wine);outline-offset:4px;border-radius:0}
.tb-app [tabindex="-1"]:is(:focus,:focus-visible){outline:none}
.tb-app :is(main,.tb-foot) a{color:var(--tb-wine);text-decoration:underline;text-decoration-thickness:1px;text-underline-offset:4px}
.tb-app :is(main,.tb-foot) a:hover{text-decoration-thickness:2px}
.tb-app main{display:block;position:relative;padding-bottom:40px}
.tb-app main :is(h1,h2,h3,h4){color:var(--tb-ink);margin:0;text-wrap:balance}
/* Chapters are authored h2 (title) > h3 > h4; the shell renders them one level up (h1 > h2 > h3) and keeps the
   authored look with .tb-ch-title / .tb-hv3 / .tb-hv4 (see shell.js tidyChapter). */
.tb-app main h2,.tb-app main h1.tb-ch-title{font:400 clamp(34px,4vw,48px)/1.12 var(--tb-serif);letter-spacing:-.03em;margin:0 0 14px;max-width:28ch}
.tb-app main :is(h3,.tb-hv3){font:400 28px/1.2 var(--tb-serif);letter-spacing:-.015em;margin:0 0 14px;max-width:none;text-transform:none}
.tb-app main :is(h4,.tb-hv4){font:600 13px/1.4 var(--tb-sans);text-transform:uppercase;letter-spacing:.08em;margin:22px 0 8px;max-width:none}
.tb-app main .tb-chapter>.tb-hv3{margin-top:48px}
.tb-app main :is(p,ul,ol,dl){margin:0 0 14px}
.tb-app main :is(p,li,dd){max-width:68ch}
.tb-app main :is(ul,ol):not([class]){padding-left:1.3em}
.tb-app main li:not([class])+li{margin-top:6px}
/* component lists are grids or rows: no list spacing (it pushed the first tile and the first step button 6px higher) */
.tb-app main :is(.tb-tiles,.tb-scan-steps,.tb-stepper-steps,.tb-hubch,.tb-sresults,.tb-layers,.tb-chmenu-list,.tb-chmenu-extra,.tb-ind-list)>li:not([class])+li{margin-top:0}
.tb-app main :is(ul,ol):not([class]) li::marker{color:var(--tb-muted)}
.tb-app main strong{font-weight:600}
.tb-app :is(code,.tb-mono){font-family:var(--tb-mono);font-size:.92em}
.tb-app ::selection{background:var(--tb-blush);color:var(--tb-ink)}
.tb-sr{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);clip-path:inset(50%);white-space:nowrap;border:0}
.tb-app .tb-skip{position:fixed;left:16px;top:-120px;z-index:100;padding:12px 16px;background:var(--tb-paper);color:var(--tb-ink);border:1px solid var(--tb-ink);font:500 15px/1.4 var(--tb-sans);text-decoration:none}
.tb-app .tb-skip:focus{top:12px}
.tb-app .tb-eyebrow,.tb-app .tb-ch-kicker{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-muted);margin:0 0 10px}
.tb-app .tb-ch-kicker{color:var(--tb-wine);margin:28px 0 6px}
.tb-app .tb-lead{font-size:19px;line-height:1.6;color:var(--tb-ink-soft);max-width:60ch;margin:0 0 18px}
.tb-app .tb-lead--small{font-size:16px}
.tb-app .tb-credit{font-size:14px;line-height:1.6;color:var(--tb-muted);margin:0 0 10px}
.tb-app .tb-hub-disclaimer{font-size:15px;line-height:1.6;color:var(--tb-ink-soft);margin:0 0 22px;padding:10px 14px;background:var(--tb-inset);border-left:3px solid var(--tb-wine);max-width:68ch}
/* breadcrumbs (13px, 44px targets) */
.tb-app .ntf-crumbs{font:13px/1.6 var(--tb-sans);color:var(--tb-muted)}
.tb-app .ntf-crumbs a{color:var(--tb-muted);display:inline-flex;align-items:center;min-height:44px}
.tb-app .ntf-crumbs [aria-current=page]{color:var(--tb-ink)}
.tb-app .ntf-crumbs a:focus-visible{outline:2px solid var(--tb-wine);outline-offset:2px}
/* phones: one line back to the region ("← Lower-limb blocks") */
@media (max-width:600px){
  .tb-app .ntf-crumbs>span,.tb-app .ntf-crumbs>a:not(:last-of-type){display:none}
  .tb-app .ntf-crumbs>a:last-of-type{display:inline-flex;gap:6px;color:var(--tb-ink);font-size:14px;text-decoration:none}
  .tb-app .ntf-crumbs>a:last-of-type::before{content:'←';color:var(--tb-wine)}
}
.tb-app .tb-prose>:last-child{margin-bottom:0}
.tb-app .tb-mount-error,.tb-app .tb-noscript{font-size:15px;color:var(--tb-danger);background:var(--tb-danger-bg);border-left:3px solid var(--tb-danger);padding:12px 16px;max-width:68ch}

/* ------------------------------------------------------------------ buttons, segmented, tools */
.tb-app .tb-btn,.tb-app .tb-seg-btn,.tb-app .tb-tool{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:44px;padding:8px 16px;border:1px solid var(--tb-line-strong);border-radius:0;background:var(--tb-paper);color:var(--tb-ink);font:500 15px/1.2 var(--tb-sans);cursor:pointer;transition:background-color .15s,border-color .15s}
.tb-app .tb-btn:hover,.tb-app .tb-seg-btn:hover,.tb-app .tb-tool:hover{border-color:var(--tb-wine);background:var(--tb-hover)}
.tb-app .tb-btn--primary{background:var(--tb-wine);border-color:var(--tb-wine);color:var(--tb-ivory)}
.tb-app .tb-btn--primary:hover{background:var(--tb-wine-hover);border-color:var(--tb-wine-hover);color:var(--tb-ivory)}
.tb-app .tb-btn:disabled{opacity:.45;cursor:not-allowed}
.tb-app .tb-seg{display:inline-flex;flex-wrap:wrap}
.tb-app .tb-seg .tb-seg-btn+.tb-seg-btn{margin-left:-1px}
.tb-app .tb-seg-btn[aria-pressed=true]{background:var(--tb-wine);border-color:var(--tb-wine);color:var(--tb-ivory);position:relative;z-index:1}
.tb-app .tb-seg-btn[aria-pressed=true]:focus-visible{outline-offset:2px}
.tb-app .tb-tool svg{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round;flex-shrink:0}

/* ------------------------------------------------------------------ sticky bar */
.tb-app .tb-bar{position:sticky;top:0;z-index:50;background:var(--tb-paper);border-bottom:1px solid var(--tb-line)}
.tb-app .tb-bar-inner{position:relative;display:flex;align-items:center;gap:8px;min-height:55px;padding-block:4px}
.tb-app .tb-bar-level{flex-shrink:0;display:flex}
.tb-app .tb-bar-home--back svg{stroke-width:1.9}
.tb-app .tb-bar-home{display:inline-flex;align-items:center;gap:6px;min-height:44px;padding:0 12px 0 8px;border:1px solid var(--tb-line-strong);color:var(--tb-ink);font:500 15px/1 var(--tb-sans);text-decoration:none;flex-shrink:0;background:var(--tb-paper)}
.tb-app .tb-bar-home svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.tb-app .tb-bar-home[hidden]{display:none}
.tb-app .tb-bar-home:hover{border-color:var(--tb-wine);background:var(--tb-hover)}
.tb-app .tb-chnav{flex:1;min-width:0;display:flex;align-items:center;gap:8px}
.tb-app .tb-chlist{display:none;list-style:none;margin:0;padding:0;gap:2px 16px;flex-wrap:nowrap;align-items:center;min-width:0;overflow:hidden}
.tb-app .tb-chlist a{display:flex;align-items:center;min-height:44px;font:14px/1.2 var(--tb-sans);color:var(--tb-muted);text-decoration:none;white-space:nowrap;border-bottom:2px solid transparent}
.tb-app .tb-chlist a:hover{color:var(--tb-ink)}
.tb-app .tb-chlist a[aria-current=page]{color:var(--tb-ink);border-bottom-color:var(--tb-wine);font-weight:500}
/* chapter menu (narrow screens): a disclosure button with a list of links */
.tb-app .tb-chmenu{position:relative;flex:1;min-width:0}
.tb-app .tb-chmenu-btn{display:flex;align-items:center;gap:8px;width:100%;min-height:44px;padding:0 12px;border:1px solid var(--tb-control);border-radius:0;background:var(--tb-paper);color:var(--tb-ink);font:16px/1.2 var(--tb-sans);cursor:pointer;text-align:left}
.tb-app .tb-chmenu-btn:hover{border-color:var(--tb-wine);background:var(--tb-hover)}
.tb-app .tb-chmenu-k{flex-shrink:0;font:400 12px/1 var(--tb-mono);text-transform:uppercase;letter-spacing:.06em;color:var(--tb-muted)}
.tb-app .tb-chmenu-cur{flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.tb-app .tb-chmenu-caret{flex-shrink:0;width:8px;height:8px;border-right:1.6px solid currentColor;border-bottom:1.6px solid currentColor;transform:translateY(-2px) rotate(45deg)}
.tb-app .tb-chmenu-btn[aria-expanded=true] .tb-chmenu-caret{transform:translateY(2px) rotate(-135deg)}
.tb-app .tb-chmenu-panel{position:absolute;left:0;top:calc(100% + 4px);z-index:60;width:max(100%,min(360px,calc(100vw - 32px)));max-width:calc(100vw - 16px);max-height:min(70vh,560px);overflow-y:auto;background:var(--tb-paper);border:1px solid var(--tb-line-strong);border-top:2px solid var(--tb-wine);box-shadow:0 12px 24px rgba(0,0,0,.14)}
.tb-app .tb-chmenu-panel[hidden]{display:none}
.tb-app .tb-chmenu-list{list-style:none;margin:0;padding:4px 0}
.tb-app .tb-chmenu-list li{margin:0}
.tb-app .tb-chmenu-list a{display:flex;align-items:center;min-height:44px;padding:8px 14px;color:var(--tb-ink);font:15px/1.35 var(--tb-sans);text-decoration:none}
.tb-app .tb-chmenu-list a:hover{background:var(--tb-hover)}
.tb-app .tb-chmenu-list a:focus-visible{outline-offset:-3px;background:var(--tb-hover)}
.tb-app .tb-chmenu-list a[aria-current=page]{background:var(--tb-blush);box-shadow:inset 3px 0 0 var(--tb-wine);font-weight:500}
/* extra rows under the chapter list: copy link (phones only), the region landing, the front door */
.tb-app .tb-chmenu-extra{list-style:none;margin:0;padding:4px 0;border-top:1px solid var(--tb-line)}
.tb-app .tb-chmenu-extra li{margin:0}
.tb-app .tb-chmenu-act{display:flex;align-items:center;gap:10px;width:100%;min-height:44px;padding:8px 14px;border:0;background:none;color:var(--tb-ink);font:15px/1.35 var(--tb-sans);text-align:left;text-decoration:none;cursor:pointer}
.tb-app .tb-chmenu-act:hover{background:var(--tb-hover)}
.tb-app .tb-chmenu-act:focus-visible{outline-offset:-3px;background:var(--tb-hover)}
.tb-app .tb-chmenu-act svg{width:18px;height:18px;flex-shrink:0;fill:none;stroke:var(--tb-wine);stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.tb-app :is(.tb-chmenu-share-li,.tb-chmenu-search-li){display:none}
@media (min-width:1240px){.tb-app .tb-bar:not(.tb-bar--menu) .tb-chlist{display:flex}.tb-app .tb-bar:not(.tb-bar--menu) .tb-chmenu{display:none}.tb-app .tb-chnav{justify-content:center}}
.tb-app .tb-bar-btn{flex-shrink:0;padding:0 14px;font-weight:400}
@media (max-width:1239px){.tb-app .tb-bar-btn{width:44px;padding:0}.tb-app .tb-bar-btn span{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);clip-path:inset(50%);white-space:nowrap}}
/* phones: home (icon), chapter menu, search, level. Copy link moves into the chapter menu; the menu spans the bar. */
@media (max-width:600px){
  .tb-app .tb-bar-inner{gap:6px}
  .tb-app .tb-bar-home span{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
  .tb-app .tb-bar-home{padding:0;min-width:44px;justify-content:center}
  .tb-app #tb-share{display:none}
  .tb-app .tb-chmenu-share-li{display:block}
  .tb-app .tb-chmenu{position:static}
  .tb-app .tb-chmenu-panel{left:var(--site-gutter,16px);right:var(--site-gutter,16px);width:auto;max-width:none}
  .tb-app .tb-chmenu-btn{padding:0 10px}
  .tb-app .tb-bar-level .ra-level-btn{padding:0 6px}
}
@media (max-width:480px){
  .tb-app .tb-chmenu-k{display:none}
  /* the chapter name may take two lines, so the bar still says where you are */
  .tb-app .tb-chmenu-cur{white-space:normal;display:-webkit-box;-webkit-box-orient:vertical;-webkit-line-clamp:2;line-clamp:2;font-size:14px;line-height:1.2;overflow-wrap:anywhere;-webkit-hyphens:auto;hyphens:auto}
}
/* very narrow phones: search moves into the chapter menu, which gives the chapter name the room */
@media (max-width:374px){
  .tb-app #tb-search-open{display:none}
  .tb-app .tb-chmenu-search-li{display:block}
}

/* search */
.tb-app .tb-sheet{position:absolute;z-index:56;left:0;right:0;top:100%;max-height:calc(100dvh - var(--ra-bar,56px) - 12px);overflow-y:auto;overscroll-behavior:contain;background:var(--tb-paper);border-bottom:2px solid var(--tb-wine);box-shadow:0 12px 24px rgba(0,0,0,.12)}
.tb-app .tb-sheet[hidden]{display:none}
.tb-app .tb-sheet-inner{padding-block:12px 16px}
.tb-app .tb-search-row{display:flex;gap:8px;align-items:stretch}
.tb-app .tb-search-input{flex:1;min-width:0;min-height:48px;padding:0 14px;border:1px solid var(--tb-control);border-radius:0;background:var(--tb-paper);color:var(--tb-ink);font:16px/1.2 var(--tb-sans);-webkit-appearance:none;appearance:none}
/* the browser's clear button: a plain wine cross, big enough to hit */
.tb-app .tb-search-input::-webkit-search-cancel-button{-webkit-appearance:none;appearance:none;width:20px;height:20px;margin-left:8px;cursor:pointer;background:linear-gradient(45deg,transparent 44%,var(--tb-wine) 44% 56%,transparent 56%),linear-gradient(-45deg,transparent 44%,var(--tb-wine) 44% 56%,transparent 56%)}
.tb-app .tb-sresults{list-style:none;margin:10px 0 0;padding:0;max-width:820px}
.tb-app .tb-sresults:empty{display:none}
.tb-app .tb-sresults li{margin:0;max-width:none}
.tb-app .tb-sres{display:block;padding:10px 12px;min-height:44px;border:1px solid var(--tb-line);border-top-width:0;background:var(--tb-paper);color:var(--tb-ink);text-decoration:none!important}
.tb-app .tb-sresults li:first-child .tb-sres{border-top-width:1px}
.tb-app .tb-sres:hover,.tb-app .tb-sres:focus-visible{background:var(--tb-hover)}
.tb-app .tb-sres-t{display:block;font:500 15px/1.35 var(--tb-sans)}
.tb-app .tb-sres-c{display:block;font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.06em;color:var(--tb-wine)}
.tb-app .tb-sres-s{display:block;font-size:14px;line-height:1.5;color:var(--tb-muted)}
.tb-app .tb-sres-tier{text-transform:none;letter-spacing:0;color:var(--tb-muted)}
.tb-app .tb-sres mark{background:var(--tb-warn-bg);color:var(--tb-ink);padding:0 1px}
.tb-app .tb-sres-none{padding:12px;color:var(--tb-muted);background:var(--tb-paper);border:1px solid var(--tb-line);list-style:none;font-size:15px}

/* ------------------------------------------------------------------ chapters + hub */
.tb-app .tb-chapter{display:block}
body.tb-app.tb-booting .tb-chapter:not(.is-current){position:absolute;left:-200vw;top:0;width:100%;visibility:hidden;pointer-events:none}
body.tb-app.tb-chapters-on .tb-chapter:not(.is-current){display:none}
.tb-app .tb-hub{padding-block:32px 24px}
.tb-app .tb-hub h1{font:400 clamp(44px,5.5vw,72px)/1.08 var(--tb-serif);letter-spacing:-.03em;margin:0 0 14px;max-width:18ch}
.tb-app .tb-hub-search{max-width:720px}
.tb-app main .tb-hub-h{font:400 clamp(26px,2.8vw,34px)/1.2 var(--tb-serif);letter-spacing:-.02em;margin:40px 0 14px}
.tb-app .tb-tiles{list-style:none;padding:0;margin:0;display:grid;gap:10px;grid-template-columns:1fr}
@media (min-width:600px){.tb-app .tb-tiles{grid-template-columns:repeat(auto-fill,minmax(250px,1fr))}}
.tb-app .tb-tiles li{margin:0;max-width:none}
.tb-app main a.tb-tile{display:flex;flex-direction:column;justify-content:center;gap:2px;min-height:68px;height:100%;padding:10px 14px;border:1px solid var(--tb-line-strong);border-left:4px solid var(--tb-wine);background:var(--tb-paper);color:var(--tb-ink);text-decoration:none}
.tb-app main a.tb-tile:hover,.tb-app main a.tb-tile:focus-visible{background:var(--tb-blush)}
.tb-app .tb-tile-t{font:500 16px/1.3 var(--tb-sans)}
.tb-app .tb-tile-d{font-size:14px;line-height:1.45;color:var(--tb-muted)}
.tb-app main .tb-hubch{list-style:none;margin:0;padding:0;max-width:820px;counter-reset:hubch}
.tb-app main .tb-hubch li{margin:0;max-width:none;counter-increment:hubch;border-top:1px solid var(--tb-line)}
.tb-app main .tb-hubch li:last-child{border-bottom:1px solid var(--tb-line)}
.tb-app main .tb-hubch a{display:grid;grid-template-columns:30px 1fr;column-gap:10px;align-items:baseline;min-height:56px;padding:10px 4px;color:var(--tb-ink);text-decoration:none}
.tb-app main .tb-hubch a::before{content:counter(hubch);grid-row:span 2;font:500 14px/1.6 var(--tb-mono);color:var(--tb-muted)}
.tb-app main .tb-hubch a:hover,.tb-app main .tb-hubch a:focus-visible{background:var(--tb-hover)}
.tb-app .tb-hubch-t{font:500 16px/1.35 var(--tb-sans)}
.tb-app .tb-hubch-d{font-size:14px;line-height:1.45;color:var(--tb-muted)}
.tb-app .tb-hub-back{margin-top:28px;font-size:15px;line-height:1.4}
.tb-app main .tb-hub-back a{display:inline-block;padding-block:11px;line-height:22px}
/* inline links in the credit lines: at least 24px tall to tap */
.tb-app :is(.tb-credit,.tb-foot) a{padding-block:4px}
.tb-app .tb-pager{display:grid;grid-template-columns:1fr;gap:8px;margin:44px 0 8px;padding-top:20px;border-top:1px solid var(--tb-line-strong)}
@media (min-width:700px){.tb-app .tb-pager{grid-template-columns:1fr auto 1fr}}
.tb-app main a.tb-pager-a{display:flex;flex-direction:column;justify-content:center;min-height:56px;padding:8px 14px;border:1px solid var(--tb-line-strong);background:var(--tb-paper);color:var(--tb-ink);text-decoration:none}
.tb-app main a.tb-pager-a:hover,.tb-app main a.tb-pager-a:focus-visible{background:var(--tb-hover);border-color:var(--tb-wine)}
.tb-app .tb-pager-a small{font:400 12px/1.5 var(--tb-mono);text-transform:uppercase;letter-spacing:.06em;color:var(--tb-muted)}
.tb-app .tb-pager-a span{font:500 15px/1.35 var(--tb-sans)}
.tb-app .tb-pager-next{text-align:right;align-items:flex-end}
.tb-app .tb-pager-hub{align-items:center;text-align:center}

/* ------------------------------------------------------------------ components */
.tb-app .tb-callout{--c:var(--tb-wine);--cb:var(--tb-inset);margin:20px 0;padding:14px 18px;background:var(--cb);border-left:3px solid var(--c);max-width:72ch}
.tb-app .tb-callout--warn{--c:var(--tb-danger);--cb:var(--tb-danger-bg)}
.tb-app .tb-callout--pearl{--c:var(--tb-wine);--cb:var(--tb-blush)}
.tb-app .tb-callout--note{--c:var(--tb-muted);--cb:var(--tb-panel)}
.tb-app .tb-callout-label{display:flex;align-items:center;gap:7px;margin:0 0 4px;font:600 12px/1.4 var(--tb-sans);text-transform:uppercase;letter-spacing:.08em;color:var(--c)}
.tb-app .tb-callout-label svg{width:16px;height:16px;flex-shrink:0}
.tb-app .tb-callout-title{font:600 16px/1.45 var(--tb-sans);margin:0 0 4px}
.tb-app .tb-callout-body{font-size:15px;line-height:1.65}
.tb-app .tb-callout-body>:last-child{margin-bottom:0}
.tb-app .tb-keypoints{margin:0 0 28px;padding:14px 18px 6px;max-width:72ch;background:var(--tb-inset);border-left:4px solid var(--tb-wine)}
.tb-app .tb-keypoints-title{margin:0 0 8px;font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-wine)}
.tb-app main .tb-keypoints ul{list-style:none;margin:0 0 8px;padding:0}
.tb-app main .tb-keypoints li{position:relative;margin:0 0 6px;padding-left:16px;font-size:16px;line-height:1.55}
.tb-app main .tb-keypoints li::before{content:'';position:absolute;left:0;top:.6em;width:6px;height:6px;background:var(--tb-wine)}
.tb-app .tb-steps{list-style:none;margin:16px 0;padding:0;max-width:72ch}
.tb-app .tb-step{display:grid;grid-template-columns:32px minmax(0,1fr);gap:14px;padding:14px 0;border-top:1px solid var(--tb-line)}
.tb-app .tb-step:last-child{border-bottom:1px solid var(--tb-line)}
.tb-app .tb-step-n{display:flex;align-items:center;justify-content:center;width:30px;height:30px;border-radius:50%;background:var(--tb-ink);color:var(--tb-paper);font:500 14px/1 var(--tb-mono)}
.tb-app .tb-step-title{font:600 16px/1.45 var(--tb-sans);margin:3px 0 4px}
.tb-app .tb-step-body{font-size:16px;line-height:1.6;color:var(--tb-ink-soft)}
.tb-app .tb-step-body>:last-child{margin-bottom:0}
.tb-app .tb-table-wrap{margin:20px 0;max-width:100%}
.tb-app .tb-table{width:100%;border-collapse:collapse;font-size:15px;line-height:1.55}
.tb-app .tb-table caption{caption-side:top;text-align:left;font:400 20px/1.35 var(--tb-serif);padding:0 0 10px}
.tb-app .tb-table thead th{font:600 12px/1.4 var(--tb-sans);text-transform:uppercase;letter-spacing:.06em;color:var(--tb-ink-soft);background:var(--tb-inset);text-align:left;padding:12px 14px;border-bottom:1px solid var(--tb-line-strong)}
.tb-app .tb-table :is(td,tbody th){padding:11px 14px;border-bottom:1px solid var(--tb-line);text-align:left;vertical-align:top}
.tb-app .tb-table tbody th{font-weight:600}
/* links in table cells jump to a block: at least 24px tall to tap */
.tb-app .tb-table a{display:inline-block;min-height:24px;padding-block:2px}
.tb-app .tb-table-scroll{overflow-x:auto}
@media (max-width:640px){
  .tb-app .tb-table--stack,.tb-app .tb-table--stack :is(tbody,tr,td,tbody th){display:block;width:100%}
  .tb-app .tb-table--stack caption{display:block}
  .tb-app .tb-table--stack thead{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}
  .tb-app .tb-table--stack tr{border:1px solid var(--tb-line);padding:12px;margin:0 0 10px;background:var(--tb-paper)}
  .tb-app .tb-table--stack :is(td,tbody th){border:0;padding:3px 0}
  .tb-app .tb-table--stack :is(td,tbody th)[data-label]::before{content:attr(data-label);display:block;font:400 12px/1.5 var(--tb-mono);text-transform:uppercase;letter-spacing:.05em;color:var(--tb-muted)}
}
.tb-app .tb-details{border-top:1px solid var(--tb-line);max-width:72ch}
.tb-app .tb-details:last-of-type{border-bottom:1px solid var(--tb-line)}
.tb-app .tb-details>summary{display:flex;align-items:center;justify-content:space-between;gap:16px;min-height:48px;padding:10px 0;cursor:pointer;list-style:none;font:500 16px/1.45 var(--tb-sans);color:var(--tb-ink)}
.tb-app .tb-details>summary::-webkit-details-marker{display:none}
.tb-app .tb-details>summary::after{content:'+';flex-shrink:0;width:20px;text-align:center;font:400 20px/1 var(--tb-mono);color:var(--tb-wine)}
.tb-app .tb-details[open]>summary::after{content:'−'}
.tb-app .tb-details>summary:hover{color:var(--tb-wine)}
.tb-app .tb-details-body{padding:0 0 16px;font-size:16px;line-height:1.65}

/* ------------------------------------------------------------------ block chapter */
.tb-app .tb-bhead{padding:4px 0 8px}
.tb-app .tb-ind{display:flex;flex-wrap:wrap;align-items:baseline;gap:4px 12px;margin:0 0 16px}
.tb-app .tb-ind-k{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-muted);margin:0}
.tb-app main .tb-ind-list{list-style:none;display:flex;flex-wrap:wrap;gap:6px;margin:0;padding:0}
.tb-app main .tb-ind-list li{margin:0;padding:3px 10px;border:1px solid var(--tb-line-strong);font-size:15px;line-height:1.4}
.tb-app .tb-glance{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));margin:8px 0 24px;border-top:1px solid var(--tb-line-strong);border-bottom:1px solid var(--tb-line)}
.tb-app .tb-glance>div{padding:10px 14px 12px 0;border-right:1px solid var(--tb-line);margin-right:14px}
.tb-app .tb-glance>div:last-child{border-right:0}
.tb-app .tb-glance dt{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-muted)}
.tb-app .tb-glance dd{margin:2px 0 0;font-size:15px;line-height:1.5}
@media (max-width:600px){.tb-app .tb-glance{grid-template-columns:1fr}.tb-app .tb-glance>div{border-right:0;border-bottom:1px solid var(--tb-line);margin-right:0}.tb-app .tb-glance>div:last-child{border-bottom:0}}
.tb-app .tb-bsec{padding:30px 0 6px;border-top:1px solid var(--tb-line)}
.tb-app .tb-bsec>:is(h3,.tb-hv3){font-size:26px}
.tb-app .tb-bgrid{display:grid;gap:0 48px}
@media (min-width:900px){.tb-app .tb-bgrid{grid-template-columns:1fr 1fr}}
.tb-app .tb-layers-wrap{margin:10px 0 18px}
.tb-app .tb-layers-k{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-muted);margin:0 0 6px}
.tb-app main .tb-layers{list-style:none;counter-reset:ly;margin:0;padding:0;max-width:52ch}
.tb-app main .tb-layers li{counter-increment:ly;display:grid;grid-template-columns:30px 1fr;padding:6px 0;border-top:1px solid var(--tb-line);font-size:16px;margin:0}
.tb-app main .tb-layers li:last-child{border-bottom:1px solid var(--tb-line)}
.tb-app main .tb-layers li::before{content:counter(ly);font:500 14px/1.65 var(--tb-mono);color:var(--tb-muted)}
.tb-app .tb-dose{max-width:72ch;padding:16px 18px;background:var(--tb-inset);border-left:4px solid var(--tb-ink)}
.tb-app main .tb-dose p{margin:0 0 8px}
.tb-app .tb-dose-k{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-muted)}
.tb-app main .tb-dose-line{font:500 21px/1.45 var(--tb-sans);margin:0 0 6px}
.tb-app .tb-dose-v{font:500 21px/1.45 var(--tb-mono)}
.tb-app .tb-dose-note{font-size:15px;color:var(--tb-ink-soft)}
.tb-app main .tb-dose-last{margin:12px 0 0;padding-top:10px;border-top:1px solid var(--tb-line);font-size:15px}
.tb-app .tb-cov-grid{display:grid;gap:20px 40px;align-items:start}
@media (min-width:900px){.tb-app .tb-cov-grid{grid-template-columns:minmax(300px,440px) minmax(0,1fr)}}
@media (min-width:900px){.tb-app .tb-cov-grid--text{grid-template-columns:minmax(0,1fr)}}
.tb-app .tb-cov{margin:0;max-width:440px}
.tb-app .tb-cov-stage{border:1px solid var(--tb-line);background:#fbf9f4;padding:8px}
.tb-app .tb-cov-svg{display:block;width:100%;height:auto}
.tb-app main .tb-cov-legend{list-style:none;margin:10px 0 0;padding:0}
.tb-app main .tb-cov-legend li{display:flex;align-items:center;gap:10px;margin:0 0 6px;font-size:15px;line-height:1.4}
.tb-app .tb-cov-sw{flex:none;width:28px;height:18px;border:1px solid var(--tb-la-dark)}
.tb-app .tb-cov-sw--dense{background:rgba(44,116,179,.78)}
.tb-app .tb-cov-sw--moderate{background:repeating-linear-gradient(45deg,var(--tb-la-dark) 0 2px,rgba(44,116,179,.32) 2px 6px)}
.tb-app .tb-cov-sw--patchy{background:radial-gradient(circle,var(--tb-la-dark) 1.1px,transparent 1.4px) 0 0/6px 6px,rgba(44,116,179,.12)}
.tb-app main .tb-cov-note{color:var(--tb-muted);font-size:14px}
.tb-app main .tb-cov-lm{font-size:14px;color:var(--tb-muted);margin:4px 0 0}
.tb-app .tb-cov-sum{font-size:17px}
.tb-app .tb-cov-text :is(h4,.tb-hv4):first-of-type{margin-top:4px}
.tb-app main .tb-list ul,.tb-app main ul.tb-pearls{padding-left:1.2em}
.tb-app main ul.tb-pearls li+li{margin-top:8px}
.tb-app .tb-bsec--examcorner{border-top:2px solid var(--tb-wine)}
.tb-app .tb-exam{display:grid;gap:16px;max-width:76ch}
.tb-app .tb-exam-q{padding:14px 18px 6px;background:var(--tb-inset);border-left:4px solid var(--tb-wine)}
.tb-app main .tb-exam-src{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-wine);margin:0 0 4px}
.tb-app .tb-exam-text{font-size:17px}
.tb-app .tb-exam-text>:last-child{margin-bottom:8px}
.tb-app .tb-exam .tb-details{border-top:1px solid var(--tb-line-strong);border-bottom:0}
.tb-app main .tb-exam-pts{padding-left:1.2em;margin:0 0 12px}
.tb-app main .tb-exam-pts li{font-size:16px;margin:0 0 6px}

/* ------------------------------------------------------------------ scan viewer */
.tb-app .tb-scan-wrap{margin:8px 0 34px}
.tb-app .tb-scan{margin:0;border-top:1px solid var(--tb-line-strong);padding-top:14px}
.tb-app .tb-scan-head{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 18px;margin:0 0 12px}
.tb-app main .tb-scan-title{font:400 22px/1.3 var(--tb-serif);margin:0;letter-spacing:-.01em}
.tb-app .tb-scan-ctrls{display:flex;flex-wrap:wrap;gap:8px}
/* Labels toggle: pressed = blush with a wine border and a ticked box; not pressed = plain with an empty box */
.tb-app .tb-scan-labbtn::before{content:'';flex-shrink:0;width:14px;height:14px;border:1.6px solid currentColor;box-sizing:border-box}
.tb-app .tb-scan-labbtn[aria-pressed=true]{background:var(--tb-blush);color:var(--tb-ink);border-color:var(--tb-wine)}
.tb-app .tb-scan-labbtn[aria-pressed=true]::before{border-color:var(--tb-wine);background:var(--tb-wine);box-shadow:inset 0 0 0 2px var(--tb-blush)}
.tb-app .tb-scan-labbtn[aria-pressed=true]:hover{background:var(--tb-blush)}
.tb-app .tb-scan-labbtn[aria-pressed=false]{background:var(--tb-paper);color:var(--tb-ink);border-color:var(--tb-line-strong)}
.tb-app .tb-scan-grid{display:grid;grid-template-columns:minmax(0,1fr);gap:16px 24px;align-items:start}
@media (min-width:1000px){.tb-app .tb-scan-grid{grid-template-columns:minmax(0,1fr) 320px}}
/* The scan teacher fits its pane, not the window: two columns (image, then the 320px step panel) only when its own box
   is wide enough (from 1000 px, as before, and in the reading column beside the desktop rail from about 1360 px); in a
   narrow box the image, steps, step text and Back · Play · Next come first. Phones (.is-phone) are laid out by scan.js. */
@media (min-width:760px){.tb-app .tb-scan-wrap{container:ra-scan / inline-size}}
@supports (container-type:inline-size){
  @media (min-width:1000px){
    .tb-app .tb-scan-grid{grid-template-columns:minmax(0,1fr)}
    @container ra-scan (min-width:780px){.tb-app .tb-scan-grid{grid-template-columns:minmax(0,1fr) 320px}}
  }
  @container ra-scan (max-width:619px){
    .tb-app .tb-scan:not(.is-phone) .tb-scan-grid{display:flex;flex-direction:column;align-items:stretch;gap:12px}
    .tb-app .tb-scan:not(.is-phone) :is(.ra-scan-col,.tb-scan-panel){display:contents}
    .tb-app .tb-scan:not(.is-phone) .tb-scan-stage{order:1}
    .tb-app .tb-scan:not(.is-phone) .ra-scan-test{order:2}
    .tb-app .tb-scan:not(.is-phone) .tb-scan-injwrap{order:3}
    .tb-app .tb-scan:not(.is-phone) .tb-scan-steps{order:4}
    .tb-app .tb-scan:not(.is-phone) .tb-scan-text{order:5;min-height:0}
    .tb-app .tb-scan:not(.is-phone) .tb-scan-nav{order:6}
    .tb-app .tb-scan:not(.is-phone) .ra-scan-info{order:7}
    .tb-app .tb-scan:not(.is-phone) .ra-scan-cov{order:8}
    .tb-app .tb-scan:not(.is-phone) .ra-scan-legend{order:9}
    .tb-app .tb-scan:not(.is-phone) .tb-scan-probe{order:10}
  }
}
.tb-app .tb-scan-stage{position:relative;display:flex;justify-content:center;background:var(--tb-panel);min-height:200px;outline-offset:4px}
.tb-app .tb-scan-stage.is-us{background:#111}
.tb-app .tb-scan-box{position:relative;max-width:100%}
.tb-app .tb-scan-box canvas{display:block}
.tb-app .tb-scan-ov{position:absolute;inset:0;pointer-events:none;font-family:var(--tb-sans);overflow:visible}
.tb-app .tb-scan-busy{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;margin:0;color:#ddd;font-size:15px;background:#111}
.tb-app .tb-scan-busy[hidden]{display:none}
/* overlay: ultrasound view = light text on dark chips; diagram view = ink on paper chips */
.tb-scan-ov .tb-ov-lab rect{fill:rgba(10,10,10,.72);stroke:rgba(255,255,255,.35);stroke-width:1}
.tb-scan-ov .tb-ov-lab text{fill:#fff;text-anchor:middle;font-weight:500}
.tb-scan-ov .tb-ov-lab line{stroke:rgba(255,255,255,.85);stroke-width:1.2}
.tb-scan-ov .tb-ov-lab circle{fill:#fff}
.tb-scan-ov[data-view=dia] .tb-ov-lab rect{fill:rgba(251,249,244,.93);stroke:#8f8574}
.tb-scan-ov[data-view=dia] .tb-ov-lab text{fill:#272722}
.tb-scan-ov[data-view=dia] .tb-ov-lab line{stroke:#272722}
.tb-scan-ov[data-view=dia] .tb-ov-lab circle{fill:#272722}
.tb-scan-ov .tb-ov-lab--nerve rect{stroke:#f2c230;stroke-width:1.6}
.tb-scan-ov .tb-ov-lab--artery rect{stroke:#e0574a;stroke-width:1.6}
.tb-scan-ov .tb-ov-lab--vein rect{stroke:#5b8fe0;stroke-width:1.6}
.tb-scan-ov .tb-ov-lab--label rect{stroke-dasharray:4 3;stroke-width:1.2}
.tb-scan-ov .tb-ov-lab--label text{font-style:italic}
.tb-scan-ov .tb-ov-orient text,.tb-scan-ov .tb-ov-ruler text{fill:#e9e9e9;font-weight:500;paint-order:stroke;stroke:rgba(0,0,0,.75);stroke-width:3px}
.tb-scan-ov .tb-ov-ruler line{stroke:#d9d9d9;stroke-width:1}
.tb-scan-ov[data-view=dia] .tb-ov-orient text,.tb-scan-ov[data-view=dia] .tb-ov-ruler text{fill:#272722;stroke:rgba(251,249,244,.9)}
.tb-scan-ov[data-view=dia] .tb-ov-ruler line{stroke:#55534d}
.tb-scan-ov .tb-ov-marker{fill:#4fb3ff}
.tb-scan-ov .tb-ov-target ellipse{fill:none;stroke:#7fd0ff;stroke-width:2;stroke-dasharray:5 4}
.tb-scan-ov[data-view=dia] .tb-ov-target ellipse{stroke:#1d5f96}
.tb-scan-ov .tb-ov-pop{fill:#ffe27a;font-weight:600;paint-order:stroke;stroke:#000;stroke-width:3px}
.tb-scan-ov[data-view=dia] .tb-ov-pop{fill:#633d3c;stroke:#fbf9f4}
.tb-app .tb-scan-panel{display:flex;flex-direction:column;gap:12px}
.tb-app main .tb-scan-steps{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));border:1px solid var(--tb-line-strong)}
.tb-app main .tb-scan-steps li{margin:0;max-width:none}
.tb-app .tb-scan-step{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:2px;width:100%;min-height:56px;padding:6px 2px;border:0;border-left:1px solid var(--tb-line-strong);border-radius:0;background:var(--tb-paper);color:var(--tb-ink);font:500 14px/1.2 var(--tb-sans);cursor:pointer}
.tb-app .tb-scan-steps li:first-child .tb-scan-step{border-left:0}
.tb-app .tb-scan-step:hover{background:var(--tb-hover)}
.tb-app .tb-scan-step-n{display:inline-flex;align-items:center;justify-content:center;width:22px;height:22px;border-radius:50%;border:1px solid currentColor;font:500 12px/1 var(--tb-mono)}
.tb-app .tb-scan-step.is-done .tb-scan-step-n{background:var(--tb-ink);color:var(--tb-paper);border-color:var(--tb-ink)}
.tb-app .tb-scan-step[aria-current=step]{background:var(--tb-wine);color:var(--tb-ivory)}
.tb-app .tb-scan-step[aria-current=step] .tb-scan-step-n{background:var(--tb-ivory);color:var(--tb-wine);border-color:var(--tb-ivory)}
.tb-app .tb-scan-step:focus-visible{outline-offset:-5px}
.tb-app .tb-scan-step[aria-current=step]:focus-visible{outline-color:var(--tb-ivory)}
.tb-app .tb-scan-text{min-height:120px;padding:12px 14px;background:var(--tb-inset);border-left:3px solid var(--tb-wine)}
.tb-app main .tb-scan-text-k{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-wine);margin:0 0 4px}
.tb-app .tb-scan-text-b{font-size:16px;line-height:1.55}
.tb-app .tb-scan-text-b>:last-child{margin-bottom:0}
.tb-app .tb-scan-nav{display:grid;grid-template-columns:1fr 1.3fr 1fr;gap:8px}
.tb-app .tb-scan-injwrap{display:flex;flex-direction:column;gap:6px}
.tb-app main .tb-scan-injlab{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-muted);margin:0}
.tb-app .tb-scan-inj{display:grid;grid-template-columns:repeat(auto-fit,minmax(90px,1fr))}
.tb-app .tb-scan-inj .tb-seg-btn{white-space:normal;text-align:center;padding:6px 8px;font-size:14px}
.tb-app .tb-scan-probe{display:grid;grid-template-columns:96px 1fr;gap:12px;align-items:center;margin:0;padding-top:12px;border-top:1px solid var(--tb-line)}
.tb-app .tb-probe-svg{width:96px;height:auto;display:block}
.tb-app .tb-scan-probe figcaption{font-size:15px;line-height:1.5;color:var(--tb-ink-soft)}
.tb-app .tb-scan-probe-k{font:400 12px/1.6 var(--tb-mono);text-transform:uppercase;letter-spacing:.08em;color:var(--tb-muted)}
.tb-app .tb-scan-cap{margin-top:14px;font-size:15px;line-height:1.55;color:var(--tb-ink-soft)}
.tb-app main .tb-scan-view{margin:0 0 8px;max-width:90ch}
.tb-app .tb-scan-view strong{color:var(--tb-ink)}
.tb-app main .tb-scan-key{display:flex;flex-wrap:wrap;gap:4px 18px;margin:0 0 8px}
.tb-app .tb-scan-key div{display:flex;gap:6px;font-size:14px}
.tb-app .tb-scan-key dt{font:500 14px/1.5 var(--tb-mono);color:var(--tb-ink)}
.tb-app main .tb-scan-key dd{margin:0}
.tb-app main .tb-scan-note{font-size:14px;color:var(--tb-muted);margin:0}
@media (max-width:999px){.tb-app .tb-scan-probe{grid-template-columns:80px 1fr}.tb-app .tb-probe-svg{width:80px}}

/* ------------------------------------------------------------------ disclaimer + credit foot */
.tb-app .tb-foot{border-top:1px solid var(--tb-line);padding:30px 0 34px;background:var(--tb-paper);color:var(--tb-muted);font-size:15px;line-height:1.7}
.tb-app .tb-foot p{margin:0 0 10px;max-width:80ch}
.tb-app .tb-foot p:last-child{margin:0}
.tb-app .tb-disclaimer{color:var(--tb-ink)}
.tb-app .ntf-footer{margin:0}

@media (max-width:760px){
  .tb-app .tb-hub{padding-top:22px}
  .tb-app main h2,.tb-app main h1.tb-ch-title{font-size:clamp(30px,8.4vw,38px)}
  .tb-app .tb-lead{font-size:17px}
  .tb-app .tb-bsec>:is(h3,.tb-hv3){font-size:24px}
  .tb-app .tb-btn,.tb-app .tb-seg-btn{padding:8px 12px}
}
@media (max-width:480px){:root:has(body.tb-app){--site-gutter:16px}}
@media (prefers-reduced-motion:reduce){.tb-app *,.tb-app *::before,.tb-app *::after{transition:none!important;animation:none!important;scroll-behavior:auto!important}}
@media print{
  .tb-app :is(.ntf-header,.ntf-footer,.tb-bar,.tb-sheet,.tb-pager,.tb-skip,.tb-scan-nav,.tb-scan-ctrls){display:none!important}
  body.tb-app .tb-chapter:not(.is-current){display:none!important}
}

/* ------------------------------------------------------------------ shared stepper (ui.js stepper()) */
.tb-app .tb-stepper{display:grid;gap:12px}
.tb-app main .tb-stepper-steps{margin:0}
.tb-app .tb-stepper-nav{grid-template-columns:1fr 1fr}

/* ------------------------------------------------------------------ level hints, long sections, 3D card, animation */
.tb-app main .ra-hidden-hint{max-width:72ch}
.tb-app main .ra-tier-badge{margin:0 0 8px}
.tb-app .tb-bsec>.ra-tier-badge+:is(h2,h3){margin-top:0}
.tb-app .ra-more{margin-top:8px}
.tb-app .ra-more>summary{font-size:15px;color:var(--tb-wine)}
.tb-app .ra-a3d{padding:14px 16px;background:var(--tb-inset);border-left:3px solid var(--tb-wine);max-width:72ch}
.tb-app .ra-a3d-lead{margin:0 0 12px;font-size:16px}
.tb-app .ra-a3d-actions{display:flex;flex-wrap:wrap;gap:8px}
.tb-app main .ra-a3d-actions a.tb-btn{text-decoration:none;color:var(--tb-ink)}
.tb-app .ra-a3d-host{margin-top:12px;min-height:200px;background:var(--tb-paper);border:1px solid var(--tb-line)}
.tb-app .ra-a3d-host[hidden]{display:none}
.tb-app .ra-a3d-loading{margin:0;padding:16px;color:var(--tb-muted);font-size:15px}
.tb-app .ra-a3d-error{margin:0;padding:16px;font-size:15px;color:var(--tb-ink)}
/* phones: the 3D card opens the explorer page (no embedded explorer in a narrow card) and sits flush */
@media (max-width:600px){
  .tb-app .ra-a3d{padding:12px;border-left-width:3px}
  .tb-app .ra-a3d-open{display:none}
}
/* chapter hidden by a level the reader just chose */
.tb-app .ra-ch-stub{padding-block:8px 32px}
.tb-app .ra-ch-stub[hidden]{display:none}
.tb-app .ra-ch-stub-actions{display:flex;flex-wrap:wrap;gap:8px;margin-top:8px}
.tb-app main .ra-ch-stub-actions a.tb-btn{text-decoration:none;color:var(--tb-ink)}
.tb-app .ra-watch{max-width:none}
.tb-app .ra-watch-fig{margin:0}
.tb-app .ra-watch-frame{display:block;width:100%;height:520px;border:1px solid var(--tb-line);background:var(--tb-paper)}
.tb-app .ra-watch-cap{margin-top:8px;font-size:15px;line-height:1.6;color:var(--tb-muted)}
.tb-app main .ra-watch-cap a{display:inline-block;min-height:24px;padding-block:2px}
@media print{.tb-app .ra-watch,.tb-app .ra-a3d-actions{display:none!important}}
/* "Back to MO" after a deep link raised the level: below 1024px the bar has no room, and a popover would cover text,
   so the chapter's hint line carries it in the page flow ("Showing Consultant content for this view · Back to MO") */
@media (max-width:1023px){
  .tb-app .tb-bar-level .ra-level-back{display:none}
}
/* footer copyright: no text under 12px (the site footer sets 10px) */
body.tb-app .ntf-footer .ntf-footer-identity>.ntf-copyright{font-size:12px}

/* ------------------------------------------------------------------ desktop: rail beside the chapters
   (frame and rail: appnav.css). With the rail, the bar names the chapter in its menu instead of repeating the list. */
@media (min-width:1024px){
  body.tb-app.ra-has-rail .tb-bar .tb-chlist{display:none!important}
  body.tb-app.ra-has-rail .tb-bar .tb-chmenu{display:block!important}
  body.tb-app.ra-has-rail .tb-hub{padding-top:28px}
}
/* Bars without a menu at this width show Settings as a button (js/appnav.js settingsButton). */
.tb-app .tb-bar .ra-settings-btn{display:none}
@media (min-width:1240px){.tb-app .tb-bar:not(.tb-bar--menu) .ra-settings-btn{display:inline-flex}}
body.tb-app.ra-has-rail .tb-bar .ra-settings-btn:not(.is-always){display:none!important}
.tb-app .tb-bar .ra-settings-btn.is-always{display:inline-flex}
.tb-app .tb-chmenu-extra .ra-settings-li svg{stroke:var(--tb-wine)}