/* Textbook lessons: restrained editorial hierarchy, clearly separated sources and self-authored visuals */
.bm-hero{padding:42px 0 44px;background:linear-gradient(120deg,var(--bg-soft),var(--panel));border-bottom:1px solid var(--line)}.bm-breadcrumb{font-size:13px;color:var(--muted)}.bm-breadcrumb a{text-decoration:underline;text-underline-offset:3px}.bm-eyebrow{display:block;margin:14px 0 8px;text-transform:uppercase;letter-spacing:.1em;color:var(--accent);font-size:11px;font-weight:800}.bm-hero h1{max-width:1000px;font-size:clamp(31px,4vw,51px);letter-spacing:-.035em;margin:12px 0}.bm-hero p{font-size:15px;color:var(--muted)}.bm-status{padding:11px 15px;border-left:3px solid #607d9b;background:var(--panel);max-width:910px;border-radius:5px;font-size:13px;line-height:1.7}.bm-layout{display:grid;grid-template-columns:minmax(0,1fr) 310px;gap:28px;padding-top:33px;padding-bottom:90px;align-items:start}.bm-article,.bm-sidebar section{background:var(--panel);border:1px solid var(--line);border-radius:15px;box-shadow:var(--shadow)}.bm-article{padding:27px 33px}.bm-outcomes{padding:20px 22px;background:var(--bg-soft);border-radius:12px;margin-bottom:24px}.bm-outcomes h2{margin:0 0 10px;font-size:19px}.bm-outcomes li{padding:3px 0;font-size:14px}.bm-unit{padding:14px 0 25px;border-bottom:1px solid var(--line)}.bm-section-no{display:block;font-size:11px;letter-spacing:.11em;color:var(--accent);font-weight:700;text-transform:uppercase}.bm-unit h2,.bm-worked h2,.bm-practice h2{font-size:24px;line-height:1.3;margin:10px 0}.bm-unit p,.bm-worked p,.bm-practice p{font-size:16px;line-height:1.95;max-width:72ch;color:var(--text)}.bm-worked,.bm-practice{margin:22px 0;padding:20px 23px;border:1px solid var(--line);border-radius:12px}.bm-worked{border-left:3px solid #377dbb}.bm-practice{border-left:3px solid #2a9372}.bm-practice button{margin:10px 0}.bm-practice #bm-answer{padding:12px 15px;background:var(--bg-soft);border-radius:7px}.bm-figure{margin:27px 0 33px;background:#fff;border:1px solid #c5d4e4;border-radius:14px;color:#1f354d;overflow:hidden}.bm-figure-top{display:flex;justify-content:space-between;gap:12px;padding:15px 20px;border-bottom:1px solid #dae3ed;background:#eff4f9;font-size:13px;font-weight:700}.bm-figure-top small{font-size:11px;color:#52667e;font-weight:400}.bm-figure label{display:flex;align-items:center;gap:9px;padding:14px 18px 2px;font-size:13px;font-weight:700}.bm-figure label span{margin-left:auto;font-variant-numeric:tabular-nums}.bm-range{display:flex;gap:12px;align-items:center;padding:8px 18px 10px;font-size:11px;color:#5a6880}.bm-range input{width:100%;flex:1;accent-color:#275f90;cursor:pointer}.bm-render{padding:10px 14px;min-height:244px}.bm-render svg{width:100%;height:auto;display:block}.bm-figure figcaption{background:#f9fbfd;font-size:11px;padding:9px 16px;color:#5c6d80;border-top:1px solid #e6ebf2}.bm-sidebar{position:sticky;top:84px;max-height:calc(100vh - 100px);overflow:auto;display:grid;gap:14px}.bm-sidebar section{padding:18px}.bm-sidebar h2{font-size:17px;margin:0 0 10px}.bm-fine{font-size:12px;line-height:1.7;color:var(--muted)}.bm-sidebar ol{margin:0;padding-left:18px;font-size:12px}.bm-sidebar li{padding:9px 0;border-bottom:1px solid var(--line);line-height:1.55}.bm-sidebar li small{display:block;color:var(--muted)}.bm-chapters{display:flex;flex-direction:column;gap:3px}.bm-chapters a{font-size:12px;padding:8px;border-radius:7px;line-height:1.5}.bm-chapters a:hover,.bm-chapters a.selected{background:var(--bg-soft);color:var(--accent)}.bm-bottomnav{display:flex;justify-content:space-between;gap:8px;flex-wrap:wrap;margin:32px 0 6px}.bm-course-strip{padding:25px;background:var(--panel);border:1px solid var(--line);border-radius:17px;margin-bottom:19px}.bm-course-strip h2{font-size:23px;margin:5px 0}.bm-course-strip p{font-size:14px;color:var(--muted);max-width:750px}.bm-strip-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin:15px 0}.bm-strip-grid a{display:flex;flex-direction:column;gap:7px;background:var(--bg-soft);padding:14px;border:1px solid var(--line);border-radius:10px;font-size:12px}.bm-strip-grid a>b{color:var(--ink);font-size:14px}.bm-strip-grid a:hover{border-color:var(--accent)}.bm-course-strip>a{font-size:13px;text-decoration:underline;color:var(--accent)}.bm-lesson-link{border-left:3px solid var(--accent);padding:12px 15px;background:var(--bg-soft);font-size:13px;margin:14px 0}.bm-lesson-link a{color:var(--accent);font-weight:700;text-decoration:underline}.bm-lesson-link small{display:block;color:var(--muted);margin-top:5px}.bm-book-toc{grid-column:1;padding:20px 24px;background:var(--panel);border:1px solid var(--line);border-radius:14px}.bm-book-toc h2{font-size:21px}.bm-book-toc-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}.bm-book-toc-grid a{background:var(--bg-soft);border:1px solid var(--line);padding:12px 15px;border-radius:9px;display:grid;gap:4px}.bm-book-toc-grid a:hover{border-color:var(--accent)}.bm-book-toc-grid small{color:var(--muted)}.bm-book-toc-grid strong{font-size:13px}.bm-book-toc-grid span{font-size:11px;color:var(--accent)}@media(max-width:960px){.bm-layout{grid-template-columns:1fr}.bm-sidebar{position:static;max-height:none}.bm-book-toc-grid{grid-template-columns:1fr}}@media(max-width:650px){.bm-article{padding:17px}.bm-layout{padding-top:15px}.bm-range{gap:7px}.bm-render{padding:4px;min-height:130px}.bm-strip-grid{grid-template-columns:1fr}.bm-course-strip{padding:18px}.bm-figure-top{flex-wrap:wrap}}
/* Prevent long textbook section names and controls from widening mobile grids. */
.bm-layout>*{min-width:0}.bm-sidebar section,.bm-article,.bm-unit{min-width:0;overflow-wrap:anywhere}.bm-range input{min-width:35px}.bm-figure{max-width:100%;min-width:0}.bm-render svg{min-width:0}.bm-book-toc-grid a{min-width:0}
.bm-inline{border:1px solid var(--line);border-radius:11px;margin:26px 0;background:var(--panel);overflow:hidden}.bm-inline summary{padding:15px 19px;cursor:pointer;display:grid;gap:3px;background:var(--bg-soft)}.bm-inline summary span{font-size:11px;font-weight:800;color:var(--accent);letter-spacing:.08em;text-transform:uppercase}.bm-inline summary b{font-size:15px;color:var(--ink)}.bm-inline summary small{color:var(--muted);font-size:12px}.bm-inline-content{padding:18px 22px}.bm-inline-content h3{font-size:17px;margin:10px 0 2px}.bm-inline-content p{font-size:14px;line-height:1.8}.bm-inline-content section{border-bottom:1px solid var(--line);padding-bottom:10px}.bm-inline-content section:last-of-type{border-bottom:0}
.bm-figure-map{border:1px solid var(--line);border-radius:13px;padding:17px 22px;margin-top:22px}.bm-figure-map h2{font-size:21px}.bm-figure-map p{font-size:13px;color:var(--muted);line-height:1.75}.bm-figure-map-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.bm-figure-map-grid>div{display:grid;gap:5px;background:var(--bg-soft);padding:11px 13px;border-radius:8px;font-size:12px}.bm-figure-map-grid b{color:var(--accent)}.bm-figure-map-grid small{color:var(--muted)}@media(max-width:650px){.bm-figure-map-grid{grid-template-columns:1fr}}
/* Original source PDF is opened locally and never copied into the website. */
.bm-read-original{display:flex;align-items:center;gap:9px;flex-wrap:wrap;margin:16px 0 0}
.bm-open-pdf{font:inherit;border:1px solid var(--line);background:var(--panel);border-radius:7px;cursor:pointer;padding:6px 9px;color:var(--accent);font-size:12px}
.bm-open-pdf:hover{border-color:var(--accent);background:var(--bg-soft)}
.bm-figure-map-grid small button{margin-top:5px}
#bm-pdf-dialog{width:min(1100px,96vw);height:min(93vh,900px);max-height:94vh;max-width:96vw;border:none;border-radius:15px;padding:0;background:var(--panel);color:var(--text);box-shadow:0 10px 60px #111b344f;overflow:hidden}
#bm-pdf-dialog::backdrop{background:#071328bd}
#bm-pdf-dialog[open]{display:flex;flex-direction:column}
.bm-pdf-head{display:flex;justify-content:space-between;align-items:center;gap:10px;padding:15px 22px;background:var(--bg-soft);border-bottom:1px solid var(--line)}
.bm-pdf-head strong{display:block;font-size:17px}.bm-pdf-head small{display:block;margin-top:3px;font-size:12px;color:var(--muted)}
.bm-pdf-head button{border:1px solid var(--line);background:var(--panel);border-radius:8px;padding:9px 12px;cursor:pointer;color:var(--text)}
.bm-pdf-instructions{display:flex;align-items:center;flex-wrap:wrap;gap:8px;padding:13px 20px;font-size:13px}.bm-pdf-instructions input{max-width:100%}
.bm-pdf-instructions span{color:var(--muted);font-size:12px}
.bm-pdf-note{font-size:12px;color:var(--muted);line-height:1.6;margin:0;padding:0 20px 12px}
#bm-pdf-frame{width:100%;flex:1;border:0;min-height:270px;background:white}
@media(max-width:620px){#bm-pdf-dialog{width:100vw;height:95vh;max-width:100vw;max-height:95vh}.bm-pdf-head{padding:12px 14px}.bm-pdf-instructions{padding:10px 13px}}

/* v4 - small-screen scientific figures and accessible scrolling. */
.bm-figure .bm-render{overflow-x:auto;overscroll-behavior-x:contain}.bm-figure .bm-render>svg{min-width:620px;max-width:100%}.bm-figure:focus-within{outline:2px solid var(--accent);outline-offset:1px}.bm-worked p{white-space:normal}.bm-inline .bm-figure{margin:18px 0}.bm-inline .bm-figure figcaption{line-height:1.65}

/* Algorithm Design v5: pseudocode must keep visual structure and remain scrollable. */
.algo-code{font:500 .9rem/1.7 ui-monospace,SFMono-Regular,Consolas,monospace; white-space:pre;overflow:auto;max-width:100%;padding:20px 22px;color:#21374e;background:#eef3fa;border:1px solid #d0dce8;border-radius:12px;tab-size:4}
.bm-render svg{width:100%;height:auto;max-height:370px}
@media(max-width:500px){.algo-code{font-size:.73rem;padding:12px}}