/* Isolated 1440 prototype. Existing frozen five-degree metrics and palette only.
   No production selectors, shared header ownership or mobile design changes. */
html,body { overflow-x:visible; }
.c3b-documentary { margin:0 32px; color:var(--ink); }
.c3b-documentary * { box-sizing:border-box; }
.c3b-documentary :is(h1,h2,p,figure) { margin:0; }
.c3b-documentary .title { font-family:'Source Sans 3',sans-serif; font-size:32px; line-height:36px; font-weight:400; letter-spacing:-.32px; }
.c3b-documentary .text { font-family:'Source Sans 3',sans-serif; font-size:16px; line-height:24px; font-weight:400; letter-spacing:-.16px; }
.c3b-documentary .system { font-family:'PT Mono',monospace; font-size:13px; line-height:18px; font-weight:400; letter-spacing:normal; }
.c3b-documentary .micro { font-family:'PT Mono',monospace; font-size:11px; line-height:14px; font-weight:400; letter-spacing:normal; }
.c3b-opening { padding-top:52px; padding-bottom:32px; }
.c3b-register,.c3b-special-register { display:flex; justify-content:space-between; gap:24px; color:var(--muted); }
.c3b-opening-grid { display:grid; grid-template-columns:2fr 1fr; gap:48px; margin-top:36px; }
.c3b-series-name { margin-top:16px!important; }
.c3b-lead { max-width:42ch; }
.c3b-local-nav { display:flex; gap:32px; margin-top:32px; }
.c3b-documentary a { color:var(--ink); text-decoration:none; }
.c3b-documentary a:hover { color:var(--ui-accent); text-decoration:underline; }
.c3b-documentary :is(a,button):focus-visible { outline:2px solid var(--ui-accent); outline-offset:4px; }
.c3b-film { padding:32px 0 64px; border-top:1px solid var(--rule); scroll-margin-top:90px; }
.c3b-film-register { display:flex; justify-content:space-between; gap:24px; margin-bottom:24px; color:var(--muted); }
.c3b-film-grid { display:grid; grid-template-columns:repeat(12,minmax(0,1fr)); gap:32px; }
.c3b-film-media { grid-column:1 / span 8; }
.c3b-film-copy { grid-column:9 / span 4; }
.c3b-film-copy h2 { margin-bottom:24px; }
.c3b-film-copy p+p { margin-top:16px; }
.c3b-film-copy p:not(:first-of-type) { color:var(--muted); }
.c3b-player { position:relative; aspect-ratio:16/9; background:var(--surface); }
.c3b-player img { display:block; width:100%; height:100%; object-fit:contain; }
.c3b-player iframe { position:absolute; inset:0; width:100%; height:100%; border:0; }
.c3b-play { position:absolute; inset:0; width:100%; height:100%; padding:0; border:0; background:none; color:var(--surface); cursor:pointer; }
.c3b-play span { position:absolute; left:50%; top:50%; transform:translate(-50%,-50%); display:flex; align-items:center; gap:16px; background:var(--ink); padding:12px 16px; white-space:nowrap; }
.c3b-play b { font-weight:400; }
.c3b-play:hover span { background:var(--ui-accent); }
.c3b-film-caption { display:flex; justify-content:space-between; gap:24px; margin-top:12px; color:var(--muted); }
.c3b-film-caption a { color:var(--muted); }
.c3b-film--reverse .c3b-film-media { grid-column:5 / span 8; grid-row:1; }
.c3b-film--reverse .c3b-film-copy { grid-column:1 / span 4; grid-row:1; }
.c3b-special { padding-top:32px; border-top:1px solid var(--ink); scroll-margin-top:90px; }
.c3b-special-heading { display:flex; align-items:baseline; gap:32px; margin:32px 0; }
.c3b-special .c3b-film { border-top:0; padding-top:0; }
.c3b-special .c3b-film-media { grid-column:1 / span 7; }
.c3b-special .c3b-film-copy { grid-column:9 / span 4; }
.c3b-sources { border-top:1px solid var(--rule); padding:32px 0 64px; scroll-margin-top:90px; }
.c3b-source-grid { display:grid; grid-template-columns:1fr 1fr; gap:64px; margin-top:24px; max-width:1100px; color:var(--muted); }
.c3b-source-grid--credits { row-gap:0; min-height:120px; align-content:start; }
.c3b-source-grid--credits > p { grid-column:1 / -1; }
/* C3B.1: local text/evidence hierarchy in the existing grid only. */
.c3b-frame-label { color:var(--muted); margin-bottom:16px!important; }
#research-frame h2+p.c3b-frame-label { margin-top:32px; }
#research-frame .text+.text { margin-top:16px; }
.c3b-frame-formula { margin-top:32px!important; color:var(--muted); }
.c3b-text-credit { margin-top:24px!important; color:var(--muted); }
.c3b-documentary-still { margin-top:24px!important; width:100%; max-width:240px; }
.c3b-documentary-still img { display:block; width:100%; height:auto; }
.c3b-documentary-still figcaption { margin-top:8px; color:var(--muted); }
#result h2 { margin-bottom:24px; color:var(--ink); }
#result .text+.text { margin-top:16px; }