/* Big World Quiz · The Atlas Edition
   Palette, type stack and tone lifted from the app itself (index.html tokens). */

:root{
  --bg:#E7ECEF;
  --surface:#FFFFFF;
  --surface-2:#F3F6F8;
  --ink:#15222B;
  --muted:#5B6B78;
  --faint:#8A98A4;
  --line:#D8DFE5;
  --line-strong:#C4CDD5;
  --brand:#14586B;
  --brand-2:#0E4353;
  --brand-deep:#0F3B4C;
  --brand-tint:#E1EDF0;
  --good:#1E7A52;
  --bad:#B23A2C;
  --amber:#C8862F;
  --amber-soft:#D9A45B;
  --paper-ink-05:rgba(21,34,43,.05);
  --serif:'Fraunces', Georgia, 'Times New Roman', serif;
  --sans:'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --mono:'IBM Plex Mono', ui-monospace, 'SF Mono', Menlo, monospace;
  --wrap:1120px;
  --grain:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)' opacity='.5'/%3E%3C/svg%3E");
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
html,body{margin:0}
body{
  font-family:var(--sans);
  background:var(--bg);
  color:var(--ink);
  line-height:1.55;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
#panel-home img{max-width:100%;display:block}
a{color:var(--brand)}
h1,h2{font-family:var(--serif);font-weight:600;line-height:1.04;margin:0;text-wrap:balance}

.skip{
  position:absolute;left:-999px;top:8px;z-index:99;
  background:var(--surface);color:var(--brand);padding:8px 14px;border:1px solid var(--line-strong);
}
.skip:focus{left:8px}

:focus-visible{outline:2px solid var(--amber);outline-offset:2px}

/* ---------- Buttons ---------- */
.btn{
  display:inline-block;font-family:var(--mono);font-size:13px;letter-spacing:.08em;text-transform:uppercase;
  text-decoration:none;padding:14px 26px;border:1px solid transparent;
  transition:transform .18s ease,background .18s ease,color .18s ease,border-color .18s ease;
}
.btn:active{transform:translateY(1px)}
.btn-primary{background:var(--amber);color:var(--brand-deep);font-weight:500}
.btn-primary:hover{background:var(--amber-soft)}
.btn-line{border-color:rgba(255,255,255,.5);color:#fff}
.btn-line:hover{border-color:#fff;background:rgba(255,255,255,.08)}
.btn-ghost{border-color:rgba(255,255,255,.45);color:#fff;padding:9px 16px;font-size:12px}
.btn-ghost:hover{border-color:#fff;background:rgba(255,255,255,.1)}
.nav.solid .btn-ghost{border-color:var(--line-strong);color:var(--brand)}
.nav.solid .btn-ghost:hover{border-color:var(--brand);background:var(--brand-tint)}

/* ---------- Nav ---------- */
.nav{
  position:fixed;inset:0 0 auto 0;z-index:20;
  display:flex;align-items:center;justify-content:space-between;
  padding:14px clamp(16px,4vw,40px);
  color:#fff;
  transition:background .25s ease,color .25s ease,box-shadow .25s ease;
}
.nav.solid{
  background:color-mix(in srgb, var(--bg) 88%, transparent);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
  color:var(--ink);
  box-shadow:inset 0 -1px 0 var(--line);
}
.nav-brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:inherit}
@keyframes rose{to{transform:rotate(360deg)}}
.nav-q{height:30px;width:auto;display:block}
.nav-q-dark{display:none}
.nav.solid .nav-q-light{display:none}
.nav.solid .nav-q-dark{display:block}
.nav-word{font-family:var(--serif);font-weight:600;font-size:19px;letter-spacing:.01em;white-space:nowrap}
.nav-word em{font-style:italic;font-weight:400;color:var(--amber-soft)}
.nav.solid .nav-word em{color:var(--amber)}
.nav-links{display:flex;gap:clamp(14px,2.4vw,26px);margin-left:auto;margin-right:clamp(14px,2.4vw,26px)}
.nav-links a{
  font-family:var(--mono);font-size:11.5px;letter-spacing:.15em;text-transform:uppercase;
  text-decoration:none;color:rgba(255,255,255,.78);padding:6px 0;
  border-bottom:2px solid transparent;transition:color .16s ease,border-color .16s ease;
}
.nav-links a:hover{color:#fff;border-bottom-color:var(--amber)}
.nav.solid .nav-links a{color:var(--muted)}
.nav.solid .nav-links a:hover{color:var(--brand);border-bottom-color:var(--amber)}
@media (max-width:880px){
  .nav-links{gap:12px;margin-right:12px}
  .nav-links a{font-size:10.5px;letter-spacing:.1em}
}
@media (max-width:620px){.nav-links{display:none}}

/* ---------- Hero ---------- */
.hero{
  position:relative;min-height:100svh;
  display:flex;flex-direction:column;justify-content:center;
  color:#fff;overflow:hidden;background:var(--brand-deep);
}
.hero-media{position:absolute;inset:0;will-change:transform}
.hero-zoom{position:absolute;inset:0;animation:kb 44s ease-in-out infinite alternate;transform-origin:50% 42%}
@keyframes kb{from{transform:scale(1)}to{transform:scale(1.06)}}
/* Height stays exactly 100vh: the masthead's band reproduces this same
   cover crop via fixed-attachment backgrounds, and any oversize here would
   shift the crop and break that registration. */
.hero-img,.hero-video{
  position:absolute;inset:0;width:100%;height:100%;object-fit:cover;object-position:center 38%;
}
.hero-video{opacity:0;transition:opacity 1.2s ease}
.hero-video.ready{opacity:1}
/* Once the loop carries the motion, retire the still's own motion layers */
.hero-zoom:has(.hero-video.ready){animation:none}
.hero-zoom:has(.hero-video.ready) .hero-routes{display:none}
.hero-routes{
  position:absolute;inset:0;width:100%;height:100%;
  mix-blend-mode:screen;pointer-events:none;
}
.hero-routes .route path{
  fill:none;stroke:#F0B25E;stroke-width:2;stroke-linecap:round;
  stroke-dasharray:100;stroke-dashoffset:100;opacity:0;
  animation:routeDraw 13.5s linear infinite;
}
.hero-routes .route circle{fill:#F0B25E;opacity:0;animation:nodePulse 13.5s linear infinite}
.hero-routes .r2 path,.hero-routes .r2 circle{animation-delay:4.5s}
.hero-routes .r3 path,.hero-routes .r3 circle{animation-delay:9s}
@keyframes routeDraw{
  0%{stroke-dashoffset:100;opacity:0}
  6%{opacity:.85}
  30%{stroke-dashoffset:0;opacity:.85}
  44%{opacity:0}
  100%{stroke-dashoffset:0;opacity:0}
}
@keyframes nodePulse{
  0%{opacity:0}
  6%,34%{opacity:.9}
  46%,100%{opacity:0}
}
.hero-veil{
  position:absolute;inset:0;
  background:
    var(--grain) repeat,
    linear-gradient(92deg, rgba(13,34,44,.84) 0%, rgba(13,34,44,.5) 38%, rgba(13,34,44,.1) 64%, rgba(13,34,44,0) 78%),
    linear-gradient(180deg, rgba(15,59,76,.5) 0%, rgba(15,59,76,.16) 32%, rgba(14,37,48,.38) 74%, rgba(13,31,40,.85) 100%);
  background-blend-mode:overlay,normal,normal;
}
.hero-inner{
  position:relative;z-index:2;
  width:min(var(--wrap),100%);margin:0 auto;padding:150px 20px 40px;
}
@media (max-width:640px){.hero-inner{padding-top:185px}}
.kicker{
  font-family:var(--mono);font-size:12.5px;letter-spacing:.22em;text-transform:uppercase;
  color:var(--amber-soft);margin:0 0 22px;
}
.hero h1{font-size:clamp(37px,6.2vw,82px);text-shadow:0 2px 30px rgba(13,31,40,.45)}
.hero .lede{
  max-width:34em;font-size:clamp(16px,2.1vw,19.5px);line-height:1.6;
  color:rgba(255,255,255,.88);margin:26px 0 38px;
}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap}
.hero-foot{
  position:absolute;left:0;right:0;bottom:0;z-index:2;
  display:flex;align-items:center;justify-content:space-between;
  padding:18px clamp(16px,4vw,40px);
  font-family:var(--mono);font-size:11px;letter-spacing:.18em;text-transform:uppercase;
  color:rgba(255,255,255,.55);
}
.scroll-cue{display:flex;align-items:center;gap:10px}
.scroll-cue i{
  display:block;width:1px;height:34px;background:rgba(255,255,255,.4);position:relative;overflow:hidden;
}
.scroll-cue i::after{
  content:"";position:absolute;left:0;top:-50%;width:1px;height:50%;
  background:var(--amber);animation:drip 2.2s ease-in-out infinite;
}
@keyframes drip{60%,100%{top:110%}}
@media (max-width:640px){.hero-foot .coords{display:none}.hero-foot{justify-content:center}}

/* ---------- Stats ---------- */
.stats{background:var(--bg);border-bottom:1px solid var(--line)}
.stats-grid{
  width:min(var(--wrap),100%);margin:0 auto;padding:54px 20px;
  display:grid;grid-template-columns:repeat(4,1fr);gap:28px;
}
.stat b{
  display:block;font-family:var(--serif);font-weight:600;font-size:clamp(40px,5.4vw,64px);
  color:var(--brand);line-height:1;font-variant-numeric:tabular-nums;
}
.stat b::before{content:"";display:block;width:26px;height:2px;background:var(--amber);margin:0 0 16px}
.stat span{
  display:block;margin-top:10px;font-family:var(--mono);font-size:11.5px;
  letter-spacing:.16em;text-transform:uppercase;color:var(--muted);
}
@media (max-width:640px){.stats-grid{grid-template-columns:1fr 1fr;gap:34px 18px}}

/* ---------- Flag ribbon ---------- */
.ribbon{overflow:hidden;background:var(--surface-2);border-bottom:1px solid var(--line);padding:16px 0}
.ribbon-track{display:flex;width:max-content}
.ribbon-track.ready{animation:slide 60s linear infinite}
.ribbon:hover .ribbon-track{animation-play-state:paused}
.ribbon-set{display:flex;align-items:center;gap:30px;padding-right:30px}
.ribbon-set img{height:21px;width:auto;border:1px solid var(--line);box-shadow:0 1px 2px rgba(21,34,43,.08)}
@keyframes slide{to{transform:translateX(-50%)}}

/* ---------- Chapters ---------- */
.chapter{
  position:relative;overflow:hidden;background:var(--bg);
  scroll-margin-top:calc(var(--mast-h, 72px) + 8px);
}
.chapter.alt{background:var(--surface-2)}
.chapter{padding:clamp(72px,10vw,128px) 20px}
.chapter > .ch-copy,.chapter > .plate{position:relative;z-index:1}
.chapter{
  display:grid;grid-template-columns:1fr 1fr;gap:clamp(36px,6vw,84px);align-items:center;
}
.chapter .ch-copy,.chapter .plate{width:100%}
.chapter .ch-copy{max-width:520px;justify-self:end}
.chapter .plate{justify-self:start}
.chapter.alt .ch-copy{order:2;justify-self:start}
.chapter.alt .plate{order:1;justify-self:end}
@media (min-width:901px){
  .chapter{padding-left:max(20px,calc((100vw - var(--wrap)) / 2));padding-right:max(20px,calc((100vw - var(--wrap)) / 2))}
}
.ch-numeral{
  position:absolute;top:2px;width:auto;font-family:var(--serif);font-weight:300;font-size:clamp(180px,26vw,340px);
  line-height:.8;color:var(--brand);opacity:.07;pointer-events:none;user-select:none;z-index:0;
}
.chapter:not(.alt) .ch-numeral{left:-.05em}
.chapter.alt .ch-numeral{right:-.05em}
.ch-label{
  font-family:var(--mono);font-size:12px;letter-spacing:.2em;text-transform:uppercase;
  color:var(--brand);margin:0 0 18px;
}
.ch-label::before{content:"";display:inline-block;width:22px;height:1px;background:var(--amber);vertical-align:middle;margin-right:12px}
.ch-label.gold{color:var(--amber-soft)}
.ch-label.center::before{display:none}
.chapter h2,.event h2,.modes h2{font-size:clamp(32px,4.4vw,46px)}
.chapter p,.event p{color:var(--muted);font-size:16.5px;max-width:56ch}
.chapter h2 + p,.event h2 + p{margin-top:20px}
.chapter p + p{margin-top:14px}
.chips{
  list-style:none;display:flex;flex-wrap:wrap;gap:10px;margin:28px 0 0;padding:0;
}
.chips li{
  font-family:var(--mono);font-size:11px;letter-spacing:.1em;text-transform:uppercase;
  color:var(--brand-2);border:1px solid var(--line-strong);border-radius:999px;padding:6px 13px;
  background:var(--surface);
}
/* Each section's way in: a mono link into the tab it describes */
.ch-link{
  display:inline-block;margin:22px 0 0;
  font-family:var(--mono);font-size:12px;letter-spacing:.14em;text-transform:uppercase;
  color:var(--brand);text-decoration:none;
  border-bottom:1px solid var(--amber);padding-bottom:3px;
}
.ch-link::after{content:" \2192";color:var(--amber);}
.ch-link:hover{color:var(--amber);}
.event .ch-link{color:#EAD9B0;}
.event .ch-link:hover{color:#fff;}

/* Museum plate frames */
.plate{
  margin:0;background:var(--surface);border:1px solid var(--line-strong);
  padding:12px;box-shadow:0 1px 2px rgba(21,34,43,.06),0 14px 40px -18px rgba(21,34,43,.25);
}
.plate img{border:1px solid var(--line);width:100%;height:auto}
.plate figcaption{
  font-family:var(--mono);font-size:10.5px;letter-spacing:.16em;text-transform:uppercase;
  color:var(--muted);padding:11px 2px 2px;display:flex;align-items:center;gap:9px;
}
.plate figcaption::before{content:"";width:7px;height:7px;background:var(--amber);flex:none}
.plate.dark{border-color:rgba(255,255,255,.16);background:rgba(255,255,255,.04);box-shadow:none}
.plate.dark img{border-color:rgba(255,255,255,.12)}
.plate.dark figcaption{color:rgba(255,255,255,.55)}

@media (max-width:900px){
  .chapter{grid-template-columns:1fr;gap:40px}
  .chapter .ch-copy,.chapter.alt .ch-copy{order:1;justify-self:stretch;max-width:640px}
  .chapter .plate,.chapter.alt .plate{order:2;justify-self:stretch;max-width:640px}
}

/* ---------- Event band ---------- */
.event{
  background:
    var(--grain) repeat,
    radial-gradient(1100px 500px at 78% -10%, rgba(200,134,47,.16), transparent 60%),
    linear-gradient(160deg, var(--brand-deep), #0B2731 70%);
  background-blend-mode:overlay,normal,normal;
  color:#fff;padding:clamp(76px,10vw,130px) 20px;
}
.event-inner{
  width:min(var(--wrap),100%);margin:0 auto;
  display:grid;grid-template-columns:1fr 1.15fr;gap:clamp(36px,6vw,84px);align-items:center;
}
.event h2{color:#fff}
.event p{color:rgba(255,255,255,.78)}
@media (max-width:900px){.event-inner{grid-template-columns:1fr}}

/* A chapter whose plate never arrives: the img's onerror drops the figure and
   sets this, so the section closes up into one centered column instead of
   leaving an empty half grid. The copy is the point; the engraving is the
   frame around it. */
.chapter.plateless{grid-template-columns:1fr}
.chapter.plateless .ch-copy,.chapter.alt.plateless .ch-copy{
  justify-self:center;max-width:660px;text-align:center;
}
.chapter.plateless p{margin-left:auto;margin-right:auto}
.chapter.plateless .ch-label::before{display:none}
.chapter.plateless .chips{justify-content:center}

/* ---------- Modes ---------- */
.modes{background:var(--bg);padding:clamp(76px,10vw,130px) 20px}
.center{text-align:center}
.modes h2{margin-bottom:10px}
.modes-grid{
  width:min(var(--wrap),100%);margin:48px auto 0;
  display:grid;grid-template-columns:repeat(5,1fr);gap:16px;
}
.mode{
  background:var(--surface);border:1px solid var(--line-strong);padding:26px 22px 30px;
  position:relative;transition:transform .22s ease,box-shadow .22s ease;
}
.mode::before{
  content:"";position:absolute;left:-1px;right:-1px;top:-1px;height:3px;background:var(--amber);
  transform:scaleX(0);transform-origin:left;transition:transform .3s ease;
}
.mode:hover{transform:translateY(-4px);box-shadow:0 16px 34px -18px rgba(21,34,43,.35)}
.mode:hover::before{transform:scaleX(1)}
.mode-tag{
  display:flex;align-items:center;gap:9px;margin:0 0 14px;
  font-family:var(--mono);font-size:12px;letter-spacing:.18em;text-transform:uppercase;color:var(--ink);
}
.mode-tag i{width:9px;height:9px;background:var(--dot,var(--brand));flex:none}
.mode-q{
  margin:0;font-family:var(--serif);font-style:italic;font-weight:400;
  font-size:19px;line-height:1.4;color:var(--brand-2);
}
@media (max-width:980px){.modes-grid{grid-template-columns:1fr 1fr}}
@media (max-width:560px){.modes-grid{grid-template-columns:1fr}}

/* ---------- Footer ---------- */
.foot{
  background:#0B2028;text-align:center;
  padding:38px 20px 42px;
}
.foot-links{display:flex;justify-content:center;flex-wrap:wrap;gap:clamp(18px,4vw,40px)}
.foot-links a{
  font-family:var(--mono);font-size:11.5px;letter-spacing:.15em;text-transform:uppercase;
  text-decoration:none;color:rgba(255,255,255,.62);padding:4px 0;
  border-bottom:2px solid transparent;transition:color .16s ease,border-color .16s ease;
}
.foot-links a:hover{color:#fff;border-bottom-color:var(--amber)}
.foot-brand{
  margin:22px 0 0;font-family:var(--serif);font-weight:600;font-size:16px;
  color:rgba(255,255,255,.5);
}
.foot-brand em{font-style:italic;font-weight:400;color:var(--amber-soft);opacity:.8}

/* ---------- Reveals ---------- */
.rv{opacity:0;transform:translateY(20px);transition:opacity .7s ease,transform .7s ease}
.rv.on{opacity:1;transform:none}
.plate.rv{transition-delay:.12s}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  .rv{opacity:1;transform:none;transition:none}
  .ribbon-track,.scroll-cue i::after{animation:none}
  .hero-zoom,.hero-routes .route path,.hero-routes .route circle{animation:none}
  .hero-routes{display:none}
  .hero-media{transform:none !important}
  .mode,.btn{transition:none}
}