/* Calibra Simulations — calibrasim.com
   Layout: full-bleed flight photo on the home page, then a measured column (max 1120px) where
   every section hangs off a left "scale" label, like dimensions on an engineering drawing.
   Colours follow the visitor's light/dark setting. */
@font-face{font-family:"Archivo";src:url(/assets/fonts/archivo.woff) format("woff");font-weight:400 800;font-stretch:100% 125%;font-display:swap}
@font-face{font-family:"IBM Plex Sans";src:url(/assets/fonts/plex-sans.woff) format("woff");font-weight:400 600;font-display:swap}
@font-face{font-family:"B612 Mono";src:url(/assets/fonts/b612-mono-400.woff) format("woff");font-weight:400;font-display:swap}
@font-face{font-family:"B612 Mono";src:url(/assets/fonts/b612-mono-700.woff) format("woff");font-weight:700;font-display:swap}
:root{
  --paper:#eef2f5;
  --surface:#ffffff;
  --ink:#0f2233;
  --muted:#51667a;
  --line:#c9d3dc;
  --amber:#a35100;
  --amber-bright:#ff8f1f;
  --band:#0f2233;
  --band-ink:#eef2f5;
  --on-photo:#ffffff;
  --photo-shade:rgba(8,18,28,.72);
  --display:"Archivo","Arial Narrow",Arial,sans-serif;
  --body:"IBM Plex Sans","Segoe UI",system-ui,sans-serif;
  --mono:"B612 Mono",ui-monospace,Consolas,monospace;
  color-scheme:light;
}
@media (prefers-color-scheme: dark){
  :root{
    --paper:#0c1721;--surface:#132230;--ink:#e8eef3;--muted:#93a6b7;--line:#263a4b;
    --amber:#ff9a33;--band:#132230;--band-ink:#e8eef3;color-scheme:dark;
  }
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
@media (prefers-reduced-motion: reduce){html{scroll-behavior:auto}}
body{margin:0;background:var(--paper);color:var(--ink);font:400 17px/1.6 var(--body)}
img{max-width:100%;height:auto}
a{color:inherit}
a:focus-visible,button:focus-visible{outline:2px solid var(--amber-bright);outline-offset:3px}
.wrap{max-width:1120px;margin-inline:auto;padding-inline:20px}
.mono{font-family:var(--mono);font-size:.74rem;letter-spacing:.08em;text-transform:uppercase}
.skip{position:absolute;left:-999px}
.skip:focus{left:12px;top:12px;z-index:9;background:var(--surface);color:var(--ink);padding:8px 12px}

/* ---------- header ---------- */
header.nav{background:var(--band);color:var(--band-ink)}
header.nav.on-photo{position:absolute;inset-inline:0;z-index:2;background:transparent;color:var(--on-photo)}
header.nav .wrap{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px 28px;padding-block:20px}
.brand{display:block;line-height:0}
.brand img{display:block;height:40px;width:auto}
nav ul{list-style:none;margin:0;padding:0;display:flex;flex-wrap:wrap;gap:6px 26px}
nav a{text-decoration:none;font-weight:500;font-size:.95rem}
nav a:hover,nav a[aria-current="page"]{text-decoration:underline;text-underline-offset:6px;text-decoration-color:var(--amber-bright)}

@media (max-width:760px){header.nav.on-photo{position:static;background:var(--band);color:var(--band-ink)}}

.subnav{background:var(--surface);border-bottom:1px solid var(--line)}
.subnav ul{gap:4px 26px;padding-block:13px}
.subnav a{font-family:var(--mono);font-size:.74rem;letter-spacing:.08em;text-transform:uppercase;font-weight:400;color:var(--muted)}
.subnav a:hover,.subnav a[aria-current="page"]{color:var(--ink);text-decoration-color:var(--amber)}

/* ---------- home hero ---------- */
.hero{position:relative;color:var(--on-photo);background:
  linear-gradient(180deg,rgba(8,18,28,.55) 0,rgba(8,18,28,0) 12vw,rgba(8,18,28,0) 22vw,#0c1721 48vw),
  url(/assets/img/air_sunset2.jpg) top center/100% auto no-repeat,#0c1721}
.hero .wrap{position:relative;padding-block:min(37vw,700px) 44px}
@media (max-width:640px){.hero{background-position:0 0,70% top,0 0}}
.hero h1{font:800 clamp(3.2rem,11vw,8rem)/.88 var(--display);font-stretch:125%;letter-spacing:-.02em;margin:10px 0 0}
.hero h1 small{display:block;font:500 clamp(1.05rem,2.2vw,1.45rem)/1.35 var(--body);letter-spacing:0;margin-top:20px;max-width:34ch}
.status{display:inline-flex;align-items:center;gap:10px;color:var(--amber-bright);background:#0c1721;border:1px solid var(--amber-bright);padding:7px 12px}
.status i{width:8px;height:8px;border-radius:50%;background:var(--amber-bright)}
.cta{display:flex;flex-wrap:wrap;gap:12px;margin-top:28px}
.btn{display:inline-block;text-decoration:none;font:600 .98rem/1 var(--body);padding:15px 22px;border:1.5px solid currentColor}
.btn.solid{background:var(--amber-bright);border-color:var(--amber-bright);color:#1a0f00}
.hero .btn:hover,.band .btn:hover{background:var(--on-photo);color:#0f2233;border-color:var(--on-photo)}
main .btn:hover{background:var(--ink);color:var(--paper);border-color:var(--ink)}
.spec{position:relative;display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid rgba(255,255,255,.35);margin:44px 0 0}
.spec div{padding:14px 16px 0 0}
.spec dt{font-family:var(--mono);font-size:.66rem;letter-spacing:.1em;text-transform:uppercase;opacity:.8}
.spec dd{margin:4px 0 0;font:600 1.05rem/1.25 var(--display)}
@media (max-width:640px){.spec{grid-template-columns:1fr 1fr;row-gap:6px}}

/* ---------- inner page title ---------- */
.pagehead{padding-block:clamp(40px,6vw,72px) clamp(28px,4vw,44px);border-bottom:1px solid var(--line)}
.pagehead .mono{color:var(--amber)}
.pagehead h1{font:800 clamp(2.4rem,6.5vw,4.6rem)/.95 var(--display);font-stretch:118%;letter-spacing:-.02em;margin:10px 0 14px;text-wrap:balance}
.pagehead p{font-size:1.15rem;max-width:60ch;margin:0}
.pagehead .benefit{margin-top:14px;font-size:1.02rem;color:var(--muted);max-width:62ch}
.ver{font-family:var(--body);font-weight:600;letter-spacing:.03em;text-transform:none}
.banner{display:block;width:100%;aspect-ratio:1800/640;object-fit:cover}

/* ---------- sections ---------- */
section{padding-block:clamp(56px,8vw,104px);border-bottom:1px solid var(--line)}
.row{display:grid;grid-template-columns:170px minmax(0,1fr);gap:20px 40px}
.row>.mono{color:var(--amber);padding-top:.7em;border-top:2px solid var(--amber);align-self:start}
@media (max-width:760px){.row{grid-template-columns:minmax(0,1fr)}.row>.mono{justify-self:start;padding-right:28px}}
h2{font:700 clamp(1.9rem,4.4vw,3.1rem)/1.02 var(--display);font-stretch:112%;letter-spacing:-.015em;margin:0 0 18px;text-wrap:balance}
h3{font:700 1.15rem/1.2 var(--display);margin:0 0 10px}
.lead{font-size:1.12rem;max-width:62ch;margin:0 0 28px}
p{max-width:65ch}
p a,li a,dd a{text-underline-offset:4px;text-decoration-color:var(--amber)}
code{font-family:var(--mono);font-size:.86em;overflow-wrap:anywhere}
.more{margin:28px 0 0;font-weight:600}

/* fuselage drawing */
.drawing{background:var(--surface);border:1px solid var(--line);padding:22px 18px 12px;overflow-x:auto}
.drawing svg{display:block;width:100%;min-width:560px;height:auto}
.drawing text{font-family:var(--mono);font-size:11px;fill:var(--muted)}
.drawing .lbl{fill:var(--ink);font-weight:700}
.drawing .cutlbl{fill:var(--amber);font-weight:700}
.pair{margin-top:28px;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px 14px}
.pair img{display:block;width:100%}
.pair figcaption{margin-top:8px;color:var(--muted)}
@media (max-width:640px){.pair{grid-template-columns:minmax(0,1fr)}}

/* engines */
.engines{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));border:1px solid var(--line);background:var(--surface)}
.engines article{padding:24px 22px 26px;display:flex;flex-direction:column;gap:8px}
.engines article+article{border-left:1px solid var(--line)}
.engines h3{font-size:1.5rem;line-height:1.05;margin:0}
.engines p{margin:0;font-size:.95rem;color:var(--muted)}
.tag{font-family:var(--mono);font-size:.68rem;letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}
.tag.in{color:var(--amber)}
.engines a{margin-top:auto;padding-top:10px;font-weight:600;font-size:.92rem;text-underline-offset:4px}
@media (max-width:760px){.engines{grid-template-columns:1fr}.engines article+article{border-left:0;border-top:1px solid var(--line)}}

/* definition lists used for feature and spec rows */
.feat{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,1fr);gap:36px;align-items:start}
.feat img{width:100%;display:block}
figure{margin:0}
.feat figcaption{margin-top:8px;color:var(--muted)}
dl.rows{margin:0}
dl.rows div{padding:14px 0;border-top:1px solid var(--line)}
dl.rows dt{font:700 1.08rem/1.25 var(--display)}
dl.rows dd{margin:3px 0 0;color:var(--muted);font-size:.96rem;max-width:65ch}
@media (max-width:860px){.feat{grid-template-columns:1fr}}

/* liveries */
.liv{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}
.liv img{display:block;width:100%;aspect-ratio:3840/2054;object-fit:cover}
.liv figcaption{display:flex;flex-wrap:wrap;justify-content:space-between;gap:4px 10px;padding-top:10px;font-weight:600}
.liv figcaption span{color:var(--muted);font-weight:400}
@media (max-width:760px){.liv{grid-template-columns:1fr}}

/* click-to-enlarge photos */
a.zoom{display:block;position:relative;cursor:zoom-in;overflow:hidden}
a.zoom::after{content:"View full size";position:absolute;inset:auto 0 0 0;padding:26px 12px 10px;font-family:var(--mono);font-size:.7rem;letter-spacing:.08em;text-transform:uppercase;color:var(--on-photo);background:linear-gradient(180deg,rgba(8,18,28,0),var(--photo-shade));opacity:0;transition:opacity .15s}
a.zoom:hover::after,a.zoom:focus-visible::after{opacity:1}
a.zoom img{transition:transform .25s}
a.zoom:hover img{transform:scale(1.03)}
@media (prefers-reduced-motion: reduce){a.zoom img,a.zoom::after{transition:none}a.zoom:hover img{transform:none}}
dialog.lightbox{border:0;padding:0;background:transparent;max-width:none;max-height:none;width:100vw;height:100dvh;display:none;flex-direction:column;align-items:center;justify-content:center;gap:10px}
dialog.lightbox[open]{display:flex}
dialog.lightbox::backdrop{background:rgba(6,12,18,.94)}
dialog.lightbox img{max-width:96vw;max-height:calc(100dvh - 80px);width:auto;height:auto;object-fit:contain;cursor:zoom-out}
.lightbox-bar{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:8px 22px;color:var(--on-photo);font-family:var(--mono);font-size:.74rem;letter-spacing:.08em;text-transform:uppercase}
.lightbox-bar a{color:var(--amber-bright)}
.lightbox-bar button{font:inherit;letter-spacing:inherit;text-transform:inherit;color:inherit;background:transparent;border:1px solid currentColor;padding:7px 14px;cursor:pointer}

/* steps, requirement tables, plain lists */
.two{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:40px}
@media (max-width:860px){.two{grid-template-columns:1fr}}
ol.steps{margin:0;padding:0;list-style:none;counter-reset:s}
ol.steps li{counter-increment:s;display:grid;grid-template-columns:2.4em minmax(0,1fr);padding:12px 0;border-top:1px solid var(--line)}
ol.steps li::before{content:counter(s);font-family:var(--mono);font-weight:700;color:var(--amber)}
ul.req{margin:0;padding:0;list-style:none}
ul.req li{padding:12px 0;border-top:1px solid var(--line);display:grid;grid-template-columns:9.5em minmax(0,1fr);gap:10px}
ul.req b{font-family:var(--mono);font-size:.7rem;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);padding-top:.3em;font-weight:400}
ul.plain{margin:0;padding:0;list-style:none;max-width:65ch}
ul.plain li{padding:10px 0;border-top:1px solid var(--line)}
.note{background:var(--surface);border:1px solid var(--line);border-left:3px solid var(--amber);padding:16px 18px;margin:24px 0 0;max-width:65ch}
.note p{margin:0}

.notes h3{margin:28px 0 4px}
.notes ul.plain li{padding:8px 0}

/* FAQ */
.faq details{border-top:1px solid var(--line);max-width:72ch}
.faq details:last-child{border-bottom:1px solid var(--line)}
.faq summary{cursor:pointer;padding:16px 28px 16px 0;font:700 1.08rem/1.3 var(--display);list-style:none;position:relative}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";position:absolute;right:4px;top:12px;font:400 1.4rem/1 var(--mono);color:var(--amber)}
.faq details[open] summary::after{content:"−"}
.faq details p{margin:0 0 16px;color:var(--muted)}

/* dark band (closing call on the home page) */
.band{background:var(--band);color:var(--band-ink);border-bottom:0}
.band .row>.mono{color:var(--amber-bright);border-color:var(--amber-bright)}
.fine{font-size:.86rem;opacity:.8;margin:14px 0 0}
.band ul.three{margin:0 0 28px;padding:0;list-style:none;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}
.band ul.three li{border-top:1px solid color-mix(in srgb,var(--band-ink) 35%,transparent);padding-top:12px;font-size:.96rem}
.band ul.three b{display:block;font:700 1.05rem/1.25 var(--display);margin-bottom:4px}
@media (max-width:760px){.band ul.three{grid-template-columns:1fr}}

/* footer */
footer{padding-block:44px 56px}
footer .wrap{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(0,1fr) minmax(0,1fr);gap:30px}
.footbrand{grid-column:1/-1}
.footbrand img{display:block;height:36px;width:auto}
.mark404{display:block;width:96px;height:96px;margin-bottom:18px}
footer h2{font-family:var(--mono);font-size:.7rem;font-stretch:100%;letter-spacing:.1em;text-transform:uppercase;color:var(--muted);margin:0 0 10px;font-weight:400}
footer ul{list-style:none;margin:0;padding:0;display:grid;gap:6px}
footer p{font-size:.88rem;color:var(--muted);margin:0 0 10px}
@media (max-width:760px){footer .wrap{grid-template-columns:1fr}}