/* Marfa Lights Field Guide — shared styles
   Themes: light, dark (default follows the device), and "night" (red-only, preserves dark adaptation). */
:root{
  --bg:#f3f4f6; --surface:#ffffff; --surface-2:#eceff3; --ink:#14181e; --ink-2:#3d4550; --muted:#5d6673;
  --rule:#d7dce2; --accent:#9a5700; --accent-ink:#ffffff; --link:#8a4d00;
  --vis:#2a78d6; --marg:#d9602a; --hid:#a3abb3; --rail:#7b4fb0; --road2:#d0368a; --zos:#2e9d5b; --r1:#86b6ef; --r2:#3987e5; --r3:#1c5cab; --r4:#0d366b; --power:#b08a00; --cell:#c03a3a; --town:#14181e;
  --shadow:0 1px 2px rgba(20,24,30,.06),0 4px 16px rgba(20,24,30,.06);
  --f-disp:"Barlow Condensed","Arial Narrow",system-ui,sans-serif;
  --f-body:"Source Sans 3","Segoe UI",system-ui,-apple-system,sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --radius:6px; --map-filter:none;
  color-scheme:light;
}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]):not([data-theme="night"]){color-scheme:dark;
    --bg:#0b0e13; --surface:#131922; --surface-2:#1a212c; --ink:#e9e7e1; --ink-2:#bcc2ca; --muted:#8b949e;
    --rule:#28313d; --accent:#f0a43a; --accent-ink:#141008; --link:#f3b561;
    --vis:#4b95ea; --marg:#e0703a; --hid:#5c6570; --rail:#b08ae0; --road2:#f06bb4; --zos:#45c07a; --r1:#184f95; --r2:#2a78d6; --r3:#6da7ec; --r4:#b7d3f6; --power:#e0c04a; --cell:#f06060; --town:#e9e7e1;
    --shadow:0 1px 2px rgba(0,0,0,.4),0 6px 20px rgba(0,0,0,.35); --map-filter:brightness(.85);}
}
:root[data-theme="dark"]{color-scheme:dark;
  --bg:#0b0e13; --surface:#131922; --surface-2:#1a212c; --ink:#e9e7e1; --ink-2:#bcc2ca; --muted:#8b949e;
  --rule:#28313d; --accent:#f0a43a; --accent-ink:#141008; --link:#f3b561;
  --vis:#4b95ea; --marg:#e0703a; --hid:#5c6570; --rail:#b08ae0; --road2:#f06bb4; --zos:#45c07a; --r1:#184f95; --r2:#2a78d6; --r3:#6da7ec; --r4:#b7d3f6; --power:#e0c04a; --cell:#f06060; --town:#e9e7e1;
  --shadow:0 1px 2px rgba(0,0,0,.4),0 6px 20px rgba(0,0,0,.35); --map-filter:brightness(.85);}
/* Night vision: red only, low luminance. Everything, including the map, goes red-on-black. */
:root[data-theme="night"]{color-scheme:dark;
  --bg:#000000; --surface:#0a0000; --surface-2:#140202; --ink:#f25a3e; --ink-2:#e8452e; --muted:#e0432d;
  --rule:#2a0805; --accent:#e5452f; --accent-ink:#000000; --link:#e5452f;
  --vis:#ff5a3c; --marg:#a8321f; --hid:#4a130b; --rail:#8e2a18; --road2:#e0482f; --zos:#7a2414; --r1:#4a130b; --r2:#7a2414; --r3:#b0301c; --r4:#e0482f; --power:#8e2a18; --cell:#c23421; --town:#d23a2a;
  --shadow:none; --map-filter:grayscale(1) brightness(.45) sepia(1) hue-rotate(-50deg) saturate(6);}

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:17px/1.6 var(--f-body)}
a{color:var(--link)}
a:hover{text-decoration-thickness:2px}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
img{max-width:100%}
[hidden]{display:none!important}
h1,h2,h3,h4{font-family:var(--f-disp);line-height:1.08;margin:0;text-wrap:balance;letter-spacing:.005em}
h1{font-size:clamp(38px,6.4vw,64px);font-weight:700}
h2{font-size:clamp(26px,3.4vw,34px);font-weight:600}
h3{font-size:21px;font-weight:600}
p{margin:0}
.mono,code{font-family:var(--f-mono);font-size:.9em}
.eyebrow{font:600 12.5px/1.2 var(--f-mono);letter-spacing:.1em;text-transform:uppercase;color:var(--accent)}
.muted{color:var(--muted)}
.num{font-variant-numeric:tabular-nums}

/* ---------- site bar */
.bar{position:sticky;top:env(safe-area-inset-top,0px);z-index:1000;background:color-mix(in srgb,var(--bg) 88%,transparent);
  backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border-bottom:1px solid var(--rule)}
.bar-in{max-width:1240px;margin:0 auto;padding-inline:16px;display:flex;align-items:center;gap:14px;min-height:54px}
.brand{font:700 20px/1 var(--f-disp);letter-spacing:.02em;color:var(--ink);text-decoration:none;white-space:nowrap;display:flex;align-items:center;gap:8px}
.brand svg{flex:none}
.brand{min-width:0}.brand>span{overflow:hidden;text-overflow:ellipsis}
/* four grouped menus; the current page's group is marked */
.nav{display:flex;gap:2px;margin-left:auto;align-items:center}
.ng{position:relative}
.ng-b{font:600 15px/1 var(--f-disp);letter-spacing:.03em;text-transform:uppercase;color:var(--ink-2);background:none;border:0;padding:10px 10px;border-radius:4px;cursor:pointer;display:flex;align-items:center;gap:6px}
.ng-b:hover,.ng-b[aria-expanded="true"]{background:var(--surface-2);color:var(--ink)}
.ng.cur .ng-b{color:var(--accent)}
.ng-b .caret{transition:transform .15s}
.ng-b[aria-expanded="true"] .caret{transform:rotate(180deg)}
.ng-p{position:absolute;top:calc(100% + 6px);left:-8px;min-width:290px;background:var(--surface);border:1px solid var(--rule);border-radius:8px;box-shadow:var(--shadow);padding:6px;display:grid;gap:2px;z-index:1100}
.ng:last-child .ng-p{left:auto;right:-8px}
.ng-p a,.msheet a{display:grid;gap:2px;text-decoration:none;color:var(--ink);padding:9px 10px;border-radius:5px}
.ng-p a b,.msheet a b{font:600 16px/1.2 var(--f-body)}
.ng-p a span,.msheet a span{font-size:13.5px;color:var(--muted);line-height:1.3}
.ng-p a:hover,.ng-p a:focus-visible,.msheet a:hover{background:var(--surface-2)}
.ng-p a[aria-current="page"] b,.msheet a[aria-current="page"] b{color:var(--accent)}
.app-btn{flex:none;font:700 14px/1 var(--f-disp);letter-spacing:.06em;text-transform:uppercase;text-decoration:none;color:var(--accent-ink);background:var(--accent);border-radius:99px;padding:10px 14px}
.menu-btn{display:none;flex:none;font:700 14px/1 var(--f-disp);letter-spacing:.06em;text-transform:uppercase;border:1px solid var(--rule);background:var(--surface);color:var(--ink);border-radius:99px;height:34px;padding:0 13px;cursor:pointer}
.theme-btn{flex:none;border:1px solid var(--rule);background:var(--surface);color:var(--ink);border-radius:99px;height:34px;padding:0 12px;
  font:600 13px/1 var(--f-disp);letter-spacing:.06em;text-transform:uppercase;cursor:pointer;display:flex;align-items:center;gap:6px}
.theme-btn .dot{width:9px;height:9px;border-radius:50%;background:var(--accent)}
.msheet{border-top:1px solid var(--rule);background:var(--bg);max-height:calc(100dvh - 60px);overflow-y:auto;padding:8px 16px 20px;display:grid;gap:14px}
.mg{display:grid;gap:2px}
.mg-t{font:600 12px/1.2 var(--f-mono);letter-spacing:.1em;text-transform:uppercase;color:var(--accent);padding:6px 10px 2px}
.fmap{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:14px 24px;padding-bottom:10px;margin-bottom:6px;border-bottom:1px solid var(--rule)}
.fmap div{display:grid;gap:4px;align-content:start}
.fmap .mg-t{padding:0 0 4px}
.fmap a{color:var(--ink-2);text-decoration:none;font-size:14.5px}
.fmap a:hover{color:var(--link);text-decoration:underline}
@media (min-width:861px){ .msheet{display:none!important} }
@media (max-width:860px){
  .nav{display:none}
  .menu-btn{display:block}
  .app-btn{padding:9px 12px;font-size:13px;margin-left:auto}
  .bar-in{gap:8px}
}
@media (max-width:600px){ .brand .bx{display:none} }
@media (max-width:430px){
  /* small phones: keep the title and the buttons on one line; the theme name stays available to screen readers */
  .brand{font-size:17px}
  .theme-btn{padding:0 10px}
  .theme-btn span:last-child{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
}
@media (max-width:340px){ .brand>span{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)} }

/* ---------- page layout */
.page{max-width:1240px;margin:0 auto;padding-inline:16px;padding-block:32px 72px;display:grid;gap:48px}
.prose{max-width:70ch;display:grid;gap:16px}
.prose h2{margin-top:18px}
.prose ul,.prose ol{margin:0;padding-left:22px;display:grid;gap:6px}
.lede{font-size:clamp(18px,2.1vw,21px);color:var(--ink-2);max-width:62ch}
.two{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,340px);gap:40px;align-items:start}
@media (max-width:900px){.two{grid-template-columns:1fr}}
.aside{border-left:3px solid var(--accent);padding:4px 0 4px 18px;display:grid;gap:10px;font-size:15.5px;color:var(--ink-2)}
.aside h3{color:var(--ink)}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,250px),1fr));gap:16px}
.card{background:var(--surface);border:1px solid var(--rule);border-radius:var(--radius);padding:18px;display:grid;gap:8px;align-content:start;
  color:inherit;text-decoration:none;box-shadow:var(--shadow)}
a.card:hover{border-color:var(--accent)}
.card h3{color:var(--ink)}
.card p{color:var(--ink-2);font-size:15.5px}
.card .go{font:600 13px var(--f-mono);color:var(--accent);letter-spacing:.04em}
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,200px),1fr));gap:1px;background:var(--rule);border:1px solid var(--rule);border-radius:var(--radius);overflow:hidden}
.stat{background:var(--surface);padding:16px 18px;display:grid;gap:4px}
.stat b{font:700 34px/1 var(--f-disp);font-variant-numeric:tabular-nums}
.stat span{font-size:14.5px;color:var(--ink-2)}
.btn{display:inline-flex;align-items:center;gap:8px;font:600 16px/1 var(--f-disp);letter-spacing:.06em;text-transform:uppercase;
  background:var(--accent);color:var(--accent-ink);border:0;border-radius:4px;padding:14px 18px;text-decoration:none;cursor:pointer}
.btn.ghost{background:transparent;color:var(--ink);border:1px solid var(--rule)}
.btn:hover{filter:brightness(1.06)}
.timeline{list-style:none;margin:0;padding:0;display:grid;gap:0;border-left:2px solid var(--rule)}
.timeline li{position:relative;padding:0 0 20px 22px}
.timeline li::before{content:"";position:absolute;left:-7px;top:6px;width:12px;height:12px;border-radius:50%;background:var(--bg);border:2px solid var(--accent)}
.timeline .yr{font:700 20px/1.2 var(--f-disp);color:var(--accent);display:block}
.refs{font-size:14.5px;color:var(--ink-2);display:grid;gap:6px;padding-left:22px;margin:0}
.refs li{padding-left:2px}
sup a{text-decoration:none;font-family:var(--f-mono);font-size:.72em;padding:0 1px}
.note{background:var(--surface-2);border-radius:var(--radius);padding:14px 16px;font-size:15.5px;color:var(--ink-2)}
.footer{border-top:1px solid var(--rule);color:var(--muted);font-size:14px}
.footer .page{padding-block:24px 40px;gap:8px}
table{border-collapse:collapse;width:100%;font-size:15px}
th,td{text-align:left;padding:8px 10px;border-bottom:1px solid var(--rule);vertical-align:top}
th{font:600 13px var(--f-mono);color:var(--muted);letter-spacing:.04em;text-transform:uppercase}
.tablewrap{overflow-x:auto}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}}

/* ---------- photographs and figures */
.photo{margin:0;display:grid;gap:6px;min-width:0}
.photo img{width:100%;height:auto;display:block;border-radius:var(--radius);background:var(--surface-2)}
.photo figcaption{font-size:13.5px;line-height:1.45;color:var(--muted)}
.photo figcaption b{color:var(--ink-2);font-weight:600}
.photo.banner img{aspect-ratio:21/8;object-fit:cover}
.photo.wide img{aspect-ratio:16/9;object-fit:cover}
.photo.plain img{background:#fff}
.photos2{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,300px),1fr));gap:16px;align-items:start}
.place .photo img{border-radius:4px}
.hero-photo{position:relative;border-radius:var(--radius);overflow:hidden;margin:0}
.hero-photo img{width:100%;height:auto;aspect-ratio:21/8;object-fit:cover;object-position:50% 72%;display:block}
.hero-photo figcaption{position:absolute;right:10px;bottom:8px;max-width:min(620px,70%);text-align:right;font-size:12px;line-height:1.35;color:#e8e8e8;text-shadow:0 0 3px #000}
@media (max-width:640px){.hero-photo figcaption{position:static;max-width:none;text-align:left;color:var(--muted);text-shadow:none;padding:6px 2px 0}}
.hero-photo figcaption a{color:#fff}
@media (max-width:640px){.photo.banner img,.hero-photo img{aspect-ratio:16/9}}
/* night vision: photos go dim and red so they don't spoil dark adaptation */
:root[data-theme="night"] .photo img,:root[data-theme="night"] .hero-photo img{filter:grayscale(1) sepia(1) hue-rotate(-50deg) saturate(5) brightness(.4)}
.prose .photo:not(.plain):not(.banner):not(.full) img{aspect-ratio:16/9;object-fit:cover}
.photo.full img{aspect-ratio:auto;object-fit:fill;background:#000}

/* ---------- fold-away detail */
details.more{border:1px solid var(--rule);border-radius:var(--radius);background:var(--surface);padding:0 16px}
details.more[open]{padding-bottom:14px}
details.more>summary{cursor:pointer;list-style:none;font:600 17px/1.3 var(--f-disp);letter-spacing:.02em;padding:13px 0;color:var(--ink);display:flex;align-items:center;gap:10px}
details.more>summary::-webkit-details-marker{display:none}
details.more>summary::before{content:"+";font:700 20px/1 var(--f-mono);color:var(--accent);width:16px}
details.more[open]>summary::before{content:"–"}
details.more>*+*{margin-top:12px}

/* app promo on the home page */
.app-promo{display:grid;grid-template-columns:96px 1fr;gap:18px;align-items:start;background:linear-gradient(135deg,#10151d,#1b2230);color:#ece9e2;border-radius:var(--radius);padding:20px 22px}
.app-promo img{border-radius:22px;box-shadow:0 6px 24px rgba(0,0,0,.4)}
.app-promo h2{margin:2px 0 8px;color:#fff}
.app-promo p{color:#c9ced6;margin:0 0 10px}
.app-promo .app-feats{list-style:none;padding:0;margin:0 0 14px;display:flex;flex-wrap:wrap;gap:6px 8px}
.app-promo .app-feats li{font-size:14px;border:1px solid #333d4b;border-radius:99px;padding:4px 10px;color:#dfe3e8}
:root[data-theme="night"] .app-promo{background:#120202;color:var(--ink)}
:root[data-theme="night"] .app-promo h2,:root[data-theme="night"] .app-promo p,:root[data-theme="night"] .app-promo li{color:var(--ink)}
@media (max-width:560px){.app-promo{grid-template-columns:1fr}.app-promo img{width:72px;height:72px}}

h2.h3{font-size:21px;font-weight:600;color:var(--ink)}
.sr-only{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}

/* science page: figure blocks */
.figs{display:grid;gap:56px}
.figblock{display:grid;gap:18px;scroll-margin-top:80px}
.figblock .photo.plain img{border:1px solid var(--rule)}
.figblock h3{font-size:24px}
.figlink{display:block;cursor:zoom-in}
:root[data-theme="night"] .figblock .photo.plain img{filter:grayscale(1) sepia(1) hue-rotate(-50deg) saturate(4) brightness(.55)}
.figblock .photo{max-width:1000px}

/* history page */
.coldopen{position:relative;border-radius:var(--radius);overflow:hidden;color:#ece9e2;
  background:linear-gradient(90deg,rgba(6,8,12,.94) 0%,rgba(6,8,12,.82) 55%,rgba(6,8,12,.35) 100%),url(../img/nps_chisos_night-1800.webp) center 70%/cover #06080c}
.coldopen .co-in{max-width:68ch;padding:clamp(24px,5vw,56px);display:grid;gap:14px}
.coldopen .eyebrow{color:#f0a43a}
.coldopen .co-big{font:600 clamp(22px,3vw,30px)/1.3 var(--f-disp);letter-spacing:.01em;color:#fff;margin:0}
.coldopen p{margin:0;color:#d5d9df;font-size:17px}
.coldopen a{color:#f3b561}
.coldopen .co-kicker{font:600 20px/1.3 var(--f-disp);color:#f0a43a;letter-spacing:.02em}
:root[data-theme="night"] .coldopen{background:#120202;color:var(--ink)}
:root[data-theme="night"] .coldopen p,:root[data-theme="night"] .coldopen .co-big{color:var(--ink)}
.names{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:8px}
.names li{font:600 16px/1 var(--f-disp);letter-spacing:.04em;text-transform:uppercase;border:1px solid var(--rule);background:var(--surface);border-radius:99px;padding:9px 14px;color:var(--ink)}
.names li:first-child{border-color:var(--accent);color:var(--accent)}
.era{margin-top:10px;display:grid;gap:2px;border-top:1px solid var(--rule);padding-top:14px}
.era h3{font-size:24px}
.voice{margin:0;border-left:3px solid var(--accent);padding:4px 0 4px 14px;font:600 18px/1.35 var(--f-disp);color:var(--ink);letter-spacing:.01em}
.voice cite{display:block;font:400 13.5px/1.4 var(--f-body);color:var(--muted);margin-top:6px;font-style:normal;letter-spacing:0}
.verdicts{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,300px),1fr));gap:14px;margin-top:18px}
.vcard{background:var(--surface);border:1px solid var(--rule);border-radius:var(--radius);padding:16px 18px;display:grid;gap:8px;align-content:start}
.vcard h3{font-size:19px;line-height:1.2}
.vcard p{margin:0;color:var(--ink-2);font-size:15px}
.badge{justify-self:start;font:600 11.5px/1 var(--f-mono);letter-spacing:.07em;text-transform:uppercase;padding:5px 8px;border-radius:4px;border:1px solid currentColor}
.b-doc{color:#1b7a47} .b-trad{color:#9a5700} .b-folk{color:#7a3fa0} .b-unver{color:#5d6673} .b-myth{color:#b42318} .b-open{color:#1c5cab}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]) .b-doc{color:#5fd08f}:root:not([data-theme="light"]) .b-trad{color:#f0a43a}:root:not([data-theme="light"]) .b-folk{color:#c9a0f0}:root:not([data-theme="light"]) .b-unver{color:#a9b1bb}:root:not([data-theme="light"]) .b-myth{color:#ff8a7a}:root:not([data-theme="light"]) .b-open{color:#8fbcf2}}
:root[data-theme="dark"] .b-doc{color:#5fd08f}:root[data-theme="dark"] .b-trad{color:#f0a43a}:root[data-theme="dark"] .b-folk{color:#c9a0f0}:root[data-theme="dark"] .b-unver{color:#a9b1bb}:root[data-theme="dark"] .b-myth{color:#ff8a7a}:root[data-theme="dark"] .b-open{color:#8fbcf2}
:root[data-theme="night"] .badge{color:var(--ink)}
.world{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,420px),1fr));gap:18px;margin-top:18px}
.wcard{background:var(--surface);border:1px solid var(--rule);border-radius:var(--radius);overflow:hidden;display:grid;align-content:start}
.wcard img{width:100%;height:auto;display:block;background:#fff}
.wcard .wbody{padding:16px 18px;display:grid;gap:10px}
.wcard h3{font-size:21px}
.wcard p{margin:0;color:var(--ink-2);font-size:15.5px}
.wcard .lesson{border-top:1px dashed var(--rule);padding-top:10px;color:var(--ink)}
.wcard .credit{font-size:12.5px;color:var(--muted)}
:root[data-theme="night"] .wcard img{filter:grayscale(1) sepia(1) hue-rotate(-50deg) saturate(4) brightness(.5)}
.culture{display:grid;gap:10px}
.prose .names{display:flex;flex-wrap:wrap;gap:8px;padding:0;list-style:none}
.world{align-items:start}