:root {
  color-scheme: dark;
  --paper: #f5efd9;
  --paper-quiet: #c9c5ae;
  --ink: #142d2a;
  --cream: #fff8df;
  --gold: #f0c96a;
  --gold-deep: #b78934;
  --coral: #d97555;
  --aqua: #75c0b3;
  --line: rgba(244, 231, 190, 0.2);
  --shadow: 0 28px 90px rgba(0, 0, 0, 0.38);
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { min-width: 320px; scroll-behavior: smooth; }
body {
  min-height: 100vh;
  margin: 0;
  overflow-x: hidden;
  background: radial-gradient(circle at 48% -20%, #234748 0, transparent 38rem), linear-gradient(160deg, #071718 0%, #03090b 70%, #081618 100%);
  color: var(--cream);
  font: 17px/1.6 "Trebuchet MS", "Segoe UI", sans-serif;
}
button, input, summary { font: inherit; }
button, summary { touch-action: manipulation; }
button { color: inherit; }
button:focus-visible, a:focus-visible, summary:focus-visible, input:focus-visible { outline: 3px solid var(--gold); outline-offset: 4px; }
[tabindex="-1"]:focus { outline: none; }
a { color: inherit; }
.skip-link {
  position: fixed; z-index: 100; top: -100px; left: 18px;
  padding: 12px 16px; border-radius: 0 0 12px 12px;
  background: var(--cream); color: var(--ink); font-weight: 700;
}
.skip-link:focus-visible { top: 0; }
.stars { position: fixed; z-index: -4; inset: 0; overflow: hidden; pointer-events: none; }
.star {
  position: absolute; width: var(--size); height: var(--size); border-radius: 50%;
  opacity: var(--opacity); background: #fff7cf;
  box-shadow: 0 0 calc(var(--size) * 4) rgba(255, 245, 197, 0.48);
  animation: twinkle var(--duration) ease-in-out infinite alternate;
  animation-delay: var(--delay);
}
.nebula {
  position: fixed; z-index: -3; width: 40rem; height: 40rem; border-radius: 50%;
  opacity: 0.16; filter: blur(70px); pointer-events: none;
}
.nebula-one { top: 22%; left: -22rem; background: #348d87; }
.nebula-two { right: -25rem; bottom: -12rem; background: #a5523f; }
.site-header, .page-footer { width: min(1280px, calc(100% - 40px)); margin: 0 auto; }
.site-header {
  display: flex; align-items: center; justify-content: space-between;
  min-height: 98px; gap: 24px; border-bottom: 1px solid var(--line);
}
.brand { display: inline-flex; align-items: center; gap: 13px; color: var(--cream); text-decoration: none; }
.brand > span:last-child { display: flex; flex-direction: column; line-height: 1; }
.brand strong { font: 700 18px/1.05 Georgia, serif; letter-spacing: .01em; }
.brand small { margin-top: 5px; color: var(--paper-quiet); font-size: 10px; letter-spacing: .2em; text-transform: uppercase; }
.brand-orbit {
  position: relative; display: grid; width: 52px; height: 52px; place-items: center;
  border: 1px solid rgba(240, 201, 106, .5); border-radius: 50%; transform: rotate(-16deg);
}
.brand-orbit::after {
  position: absolute; width: 6px; height: 6px; border-radius: 50%;
  background: var(--gold); box-shadow: 0 0 13px var(--gold);
  content: ""; transform: translateX(26px);
}
.brand-orbit span {
  width: 22px; height: 22px; border-radius: 48% 52% 45% 55%;
  background: radial-gradient(circle at 66% 28%, #b7d29d 0 11%, transparent 12%), radial-gradient(circle at 32% 60%, #b7d29d 0 15%, transparent 16%), linear-gradient(145deg, #77b9b8, #2e6974);
  transform: rotate(16deg);
}
.header-actions { display: flex; align-items: center; gap: 9px; }
.quiet-button, .footer-link { border: 1px solid var(--line); background: rgba(255, 255, 255, .03); }
.quiet-button {
  display: inline-flex; align-items: center; min-height: 44px; gap: 9px;
  padding: 7px 12px; border-radius: 999px; color: var(--paper-quiet); cursor: pointer;
}
.switch-track {
  display: flex; width: 35px; height: 20px; align-items: center; padding: 3px;
  border-radius: 99px; background: rgba(240, 201, 106, .2);
}
.switch-thumb { width: 14px; height: 14px; border-radius: 50%; background: var(--gold); transition: transform 180ms ease; }
html[lang="es"] .switch-thumb { transform: translateX(15px); }
main { width: min(1280px, calc(100% - 40px)); margin: 0 auto; padding: 42px 0 70px; }
.journey-shell {
  overflow: hidden; border: 1px solid var(--line); border-radius: 8px 28px 28px 28px;
  background: linear-gradient(145deg, rgba(14, 40, 40, .82), rgba(4, 14, 16, .94));
  box-shadow: var(--shadow), inset 7px 0 0 rgba(240, 201, 106, .7);
  backdrop-filter: blur(18px);
}
.location-bar { padding: 20px 30px; border-bottom: 1px solid var(--line); background: rgba(2, 10, 11, .35); }
.location-bar ol {
  display: grid; grid-template-columns: repeat(5, 1fr);
  max-width: 890px; margin: 0 auto; padding: 0; list-style: none;
}
.location-bar li { position: relative; min-width: 0; }
.location-bar li:not(:last-child)::after {
  position: absolute; z-index: 0; top: 10px; left: calc(50% + 13px); right: calc(-50% + 13px);
  height: 1px; background: var(--line); content: "";
}
.step-button {
  position: relative; z-index: 1; display: flex; width: 100%;
  flex-direction: column; align-items: center; gap: 7px; padding: 0 5px;
  border: 0; background: transparent; color: #7f918b; cursor: pointer;
}
.step-dot {
  display: grid; width: 21px; height: 21px; place-items: center;
  border: 1px solid rgba(241, 227, 184, .3); border-radius: 50%;
  background: #0a1b1c; transition: background 180ms ease, border-color 180ms ease, transform 180ms ease;
}
.step-dot::after { width: 5px; height: 5px; border-radius: 50%; background: currentColor; content: ""; }
.step-name { overflow: hidden; max-width: 100%; font-size: 11px; letter-spacing: .04em; text-overflow: ellipsis; white-space: nowrap; }
.step-button.is-past { color: var(--aqua); }
.step-button[aria-current="step"] { color: var(--gold); }
.step-button[aria-current="step"] .step-dot {
  border-color: var(--gold); background: rgba(240, 201, 106, .12);
  box-shadow: 0 0 20px rgba(240, 201, 106, .28); transform: scale(1.18);
}
.journey-grid { display: grid; grid-template-columns: minmax(310px, .78fr) minmax(520px, 1.22fr); min-height: 650px; }
.story-panel {
  position: relative; z-index: 2; padding: clamp(38px, 5vw, 72px);
  border-right: 1px solid var(--line);
  background: linear-gradient(135deg, rgba(250, 241, 208, .98), rgba(230, 225, 199, .94)), var(--paper);
  color: var(--ink);
}
.story-panel::before {
  position: absolute; top: 22px; right: 22px; width: 46px; height: 46px;
  border: 1px solid rgba(20, 45, 42, .16); border-radius: 50%; content: "";
}
.story-panel::after {
  position: absolute; top: 37px; right: 11px; width: 70px; height: 16px;
  border-top: 1px solid rgba(20, 45, 42, .14); border-radius: 50%; content: ""; transform: rotate(-18deg);
}
.stage-number, .stage-kicker { margin: 0; text-transform: uppercase; }
.stage-number { color: var(--gold-deep); font: 700 11px/1 "Trebuchet MS", sans-serif; letter-spacing: .18em; }
.stage-kicker { margin-top: 34px; color: #5f7066; font-size: 11px; font-weight: 700; letter-spacing: .14em; }
.story-panel h1 {
  max-width: 620px; margin: 11px 0 22px;
  font: 400 clamp(42px, 5vw, 71px)/.97 Georgia, "Times New Roman", serif;
  letter-spacing: -.05em;
}
.essential { max-width: 590px; margin: 0; color: #344b45; font: 400 clamp(18px, 1.8vw, 22px)/1.52 Georgia, serif; }
.question-card {
  display: grid; grid-template-columns: 44px 1fr; align-items: center; gap: 14px;
  margin: 34px 0 24px; padding: 17px 19px;
  border: 1px solid rgba(183, 137, 52, .26); border-radius: 4px 18px 18px 4px;
  background: rgba(255, 249, 226, .6); box-shadow: inset 5px 0 0 var(--gold-deep);
}
.question-card p { margin: 0; font-weight: 700; line-height: 1.4; }
.question-mark {
  display: grid; width: 38px; height: 38px; place-items: center;
  border: 1px solid rgba(183, 137, 52, .42); border-radius: 50%;
  color: #8d6828; font: 700 20px Georgia, serif;
}
.detail-drawer { border-top: 1px solid rgba(20, 45, 42, .16); border-bottom: 1px solid rgba(20, 45, 42, .16); }
.detail-drawer summary {
  display: flex; align-items: center; justify-content: space-between; min-height: 54px; gap: 18px;
  cursor: pointer; font-size: 14px; font-weight: 700; list-style: none;
}
.detail-drawer summary::-webkit-details-marker { display: none; }
.summary-icon {
  display: grid; width: 28px; height: 28px; flex: 0 0 auto; place-items: center;
  border: 1px solid rgba(20, 45, 42, .22); border-radius: 50%; transition: transform 180ms ease;
}
.detail-drawer[open] .summary-icon { transform: rotate(45deg); }
.detail-content { padding: 0 0 18px; }
.detail-item {
  display: grid; grid-template-columns: minmax(105px, .32fr) 1fr; gap: 17px;
  padding: 15px 0; border-top: 1px dashed rgba(20, 45, 42, .14);
}
.detail-item strong { color: #956d29; font-size: 11px; letter-spacing: .08em; text-transform: uppercase; }
.detail-item p { margin: 0; font-size: 14px; line-height: 1.55; }
.scale-note { margin: 20px 0 0; color: #65746b; font-size: 11px; }
.cosmos-window {
  position: relative; display: grid; min-height: 650px; grid-template-rows: auto 1fr auto;
  overflow: hidden; background: radial-gradient(circle at 50% 46%, rgba(44, 98, 98, .2), transparent 45%), linear-gradient(145deg, #08191a, #03090b);
  isolation: isolate;
}
.cosmos-window::before {
  position: absolute; z-index: -1; inset: 0; opacity: .27;
  background-image: linear-gradient(rgba(255, 255, 255, .035) 1px, transparent 1px), linear-gradient(90deg, rgba(255, 255, 255, .035) 1px, transparent 1px);
  background-size: 48px 48px; content: ""; mask-image: radial-gradient(circle, black 0, transparent 72%);
}
.window-label {
  z-index: 5; display: inline-flex; align-items: center; justify-self: start; gap: 9px;
  margin: 24px 26px 0; color: #9caaa3; font-size: 11px; letter-spacing: .11em; text-transform: uppercase;
}
.live-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--coral); box-shadow: 0 0 11px rgba(217, 117, 85, .7); }
.scene {
  position: relative; display: grid; min-height: 475px; place-items: center; padding: 35px;
  transition: opacity 180ms ease, transform 260ms ease;
}
.scene.is-leaving { opacity: 0; transform: scale(.96); }
.interaction-dock {
  z-index: 6; display: flex; min-height: 92px; align-items: center; justify-content: center;
  padding: 17px 24px; border-top: 1px solid var(--line); background: rgba(2, 10, 11, .54);
}
.interaction-card { display: flex; width: min(100%, 560px); align-items: center; justify-content: space-between; gap: 18px; }
.interaction-card p { margin: 0; color: #bec8c1; font-size: 13px; }
.interaction-button {
  min-height: 44px; flex: 0 0 auto; padding: 10px 17px;
  border: 1px solid rgba(240, 201, 106, .55); border-radius: 999px;
  background: rgba(240, 201, 106, .1); color: var(--cream);
  cursor: pointer; font-size: 13px; font-weight: 700;
}
.interaction-button:hover { background: rgba(240, 201, 106, .18); }
.journey-controls {
  display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 14px;
  padding: 19px 26px; border-top: 1px solid var(--line); background: rgba(3, 12, 13, .8);
}
.control-button, .earth-button { min-height: 48px; border-radius: 999px; cursor: pointer; font-weight: 700; }
.control-button { display: inline-flex; align-items: center; gap: 11px; border: 1px solid var(--line); padding: 11px 19px; }
.control-button.secondary { justify-self: start; background: transparent; }
.control-button.primary { grid-column: 3; justify-self: end; border-color: var(--gold); background: var(--gold); color: #1d2a26; }
.control-button:disabled { opacity: .35; cursor: default; }
.earth-button { display: inline-flex; align-items: center; gap: 10px; border: 0; background: transparent; color: #b7c1bb; }
.mini-earth {
  width: 24px; height: 24px; border: 1px solid rgba(255, 255, 255, .25); border-radius: 50%;
  background: radial-gradient(circle at 68% 28%, #b7d29d 0 10%, transparent 11%), radial-gradient(circle at 35% 60%, #b7d29d 0 15%, transparent 16%), linear-gradient(145deg, #77b9b8, #2e6974);
}
/* Earth */
.earth-scene { position: relative; display: grid; width: min(410px, 80vw); aspect-ratio: 1; place-items: center; }
.sun-glow {
  position: absolute; top: -18%; right: -26%; width: 54%; height: 54%; border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 234, 148, .32), rgba(255, 221, 120, .05) 45%, transparent 70%);
}
.earth-orbit-ring {
  position: absolute; width: 98%; height: 44%; border: 1px solid rgba(240, 201, 106, .17);
  border-radius: 50%; transform: rotate(-15deg);
}
.earth-visual {
  position: relative; width: 54%; aspect-ratio: 1; overflow: hidden;
  border: 1px solid rgba(192, 240, 229, .34); border-radius: 50%;
  background: radial-gradient(ellipse at 70% 18%, #a4c78e 0 9%, transparent 10%), radial-gradient(ellipse at 26% 52%, #accb8f 0 13%, transparent 14%), radial-gradient(ellipse at 58% 68%, #7da96f 0 10%, transparent 11%), radial-gradient(circle at 34% 30%, rgba(255, 255, 255, .42), transparent 18%), linear-gradient(145deg, #73c6ce, #226c7e 65%, #0b3544);
  box-shadow: inset -50px -18px 55px rgba(0, 0, 0, .54), inset 22px 14px 25px rgba(255, 255, 255, .14), 0 0 70px rgba(72, 174, 181, .27);
}
.earth-visual::before, .earth-visual::after {
  position: absolute; border: 6px solid rgba(255, 255, 255, .18); border-left-color: transparent;
  border-right-color: transparent; border-radius: 50%; content: "";
}
.earth-visual::before { inset: 18% -7% 55% -7%; transform: rotate(12deg); }
.earth-visual::after { inset: 57% -12% 17% -12%; transform: rotate(-8deg); }
.earth-visual.is-spinning { animation: earth-turn 3.8s linear infinite; }
.moon-orbit {
  position: absolute; width: 76%; height: 34%; border: 1px solid rgba(245, 239, 217, .22);
  border-radius: 50%; animation: orbit-turn 12s linear infinite;
}
.moon {
  position: absolute; top: 50%; right: -8px; width: 19px; height: 19px; border-radius: 50%;
  background: radial-gradient(circle at 35% 30%, #f6f1db, #8f948d);
  box-shadow: 0 0 15px rgba(255, 248, 223, .18); transform: translateY(-50%);
}
/* Solar system */
.solar-scene { width: min(100%, 750px); }
.solar-rail {
  position: relative; display: grid; grid-template-columns: 78px repeat(8, 1fr);
  align-items: center; min-height: 310px; gap: clamp(4px, 1.1vw, 13px);
}
.solar-rail::before {
  position: absolute; z-index: -1; top: 50%; left: 7%; right: 0; height: 1px;
  background: linear-gradient(90deg, rgba(240, 201, 106, .6), rgba(255, 255, 255, .08)); content: "";
}
.sun {
  width: 70px; aspect-ratio: 1; border-radius: 50%;
  background: radial-gradient(circle at 35% 30%, #fff8bd, #f5bc4a 40%, #db6c31 72%);
  box-shadow: 0 0 55px rgba(240, 167, 62, .55);
}
.planet-button {
  display: flex; min-width: 44px; min-height: 80px; flex-direction: column; align-items: center;
  justify-content: center; gap: 11px; border: 0; background: transparent; cursor: pointer;
}
.planet-sphere {
  position: relative; display: block; width: var(--planet-size); height: var(--planet-size);
  min-width: 10px; min-height: 10px; border-radius: 50%; background: var(--planet-color);
  box-shadow: inset -5px -2px 8px rgba(0, 0, 0, .35); transition: transform 180ms ease, box-shadow 180ms ease;
}
.planet-button:hover .planet-sphere, .planet-button:focus-visible .planet-sphere, .planet-button.is-selected .planet-sphere {
  box-shadow: inset -5px -2px 8px rgba(0, 0, 0, .28), 0 0 22px rgba(240, 201, 106, .55);
  transform: scale(1.22);
}
.planet-number { color: #849792; font-size: 10px; }
.planet-button.is-selected .planet-number { color: var(--gold); }
.planet-sphere.mercury { --planet-size: 13px; --planet-color: linear-gradient(145deg, #c7b9a6, #665e56); }
.planet-sphere.venus { --planet-size: 18px; --planet-color: linear-gradient(145deg, #f1d28d, #a87340); }
.planet-sphere.earth { --planet-size: 19px; --planet-color: linear-gradient(145deg, #75bfc3, #326c84); }
.planet-sphere.mars { --planet-size: 15px; --planet-color: linear-gradient(145deg, #d87a54, #793728); }
.planet-sphere.jupiter {
  --planet-size: 52px; --planet-color: repeating-linear-gradient(175deg, #d6b58f 0 7px, #9f6d4e 8px 12px, #ead2ac 13px 18px);
}
.planet-sphere.saturn { --planet-size: 44px; --planet-color: linear-gradient(145deg, #e6d5a2, #a88a57); }
.planet-sphere.saturn::after {
  position: absolute; inset: 40% -30%; border: 4px double rgba(225, 203, 143, .74);
  border-radius: 50%; content: ""; transform: rotate(-16deg);
}
.planet-sphere.uranus { --planet-size: 30px; --planet-color: linear-gradient(145deg, #b8e2db, #5b9b9f); }
.planet-sphere.neptune { --planet-size: 29px; --planet-color: linear-gradient(145deg, #6f9ed5, #244b8b); }
.planet-readout { min-height: 65px; margin-top: -18px; text-align: center; }
.planet-readout strong { display: block; color: var(--gold); font: 400 23px Georgia, serif; }
.planet-readout span { color: #b6c1ba; font-size: 13px; }
/* Milky Way */
.galaxy-scene { position: relative; width: min(560px, 86vw); aspect-ratio: 1.55; }
.galaxy {
  position: absolute; inset: 8%; border-radius: 50%;
  background: radial-gradient(ellipse at center, #fff8d4 0 3%, #e8c474 4%, rgba(195, 152, 94, .32) 10%, transparent 22%), repeating-radial-gradient(ellipse at center, transparent 0 8%, rgba(102, 179, 176, .09) 9% 11%, transparent 12% 18%);
  box-shadow: inset 0 0 80px rgba(102, 179, 176, .13); transform: rotate(-12deg);
}
.galaxy::before, .galaxy::after {
  position: absolute; inset: 10% 5%; border: 20px solid transparent;
  border-top-color: rgba(213, 233, 220, .28); border-radius: 50%;
  content: ""; filter: blur(3px); transform: rotate(24deg);
}
.galaxy::after { border-top-color: rgba(99, 168, 166, .25); transform: rotate(204deg) scale(.82); }
.galaxy-stars { position: absolute; inset: 0; }
.galaxy-stars i {
  position: absolute; width: var(--s); height: var(--s); border-radius: 50%;
  background: rgba(255, 249, 218, var(--a)); box-shadow: 0 0 8px rgba(255, 245, 197, .35);
}
.sun-marker {
  position: absolute; z-index: 4; top: 61%; left: 66%; display: grid; width: 48px; height: 48px;
  place-items: center; border: 1px solid transparent; border-radius: 50%; background: transparent; cursor: pointer;
}
.sun-marker span { width: 8px; height: 8px; border-radius: 50%; background: var(--gold); box-shadow: 0 0 9px var(--gold), 0 0 22px rgba(240, 201, 106, .5); }
.sun-marker::after {
  position: absolute; width: 26px; height: 26px; border: 1px solid rgba(240, 201, 106, .42);
  border-radius: 50%; content: ""; animation: pulse-ring 2s ease-out infinite;
}
.sun-marker.is-found::before {
  position: absolute; bottom: -18px; left: 50%; color: var(--gold);
  content: "☀"; font-size: 16px; transform: translateX(-50%);
}
/* Cosmic web */
.web-scene { width: min(620px, 90vw); }
.cosmic-web { width: 100%; height: auto; overflow: visible; }
.web-line {
  opacity: .05; stroke: #8ccfc3; stroke-linecap: round; stroke-width: 1.2;
  transition: opacity 550ms ease, stroke-dashoffset 900ms ease;
  stroke-dasharray: 8 6; stroke-dashoffset: 90;
}
.web-node { fill: #e7d49f; filter: drop-shadow(0 0 5px rgba(231, 212, 159, .65)); }
.web-halo { fill: rgba(95, 170, 164, .06); stroke: rgba(95, 170, 164, .08); }
.cosmic-web.is-revealed .web-line { opacity: .52; stroke-dashoffset: 0; }
.cosmic-web.is-revealed .web-halo { fill: rgba(95, 170, 164, .1); stroke: rgba(95, 170, 164, .24); }
/* Observable universe */
.observable-scene {
  display: grid; width: min(620px, 90vw);
  grid-template-columns: minmax(250px, 1fr) minmax(160px, .65fr);
  align-items: center; gap: 30px;
}
.horizon {
  position: relative; display: grid; width: min(380px, 70vw); aspect-ratio: 1;
  place-items: center; justify-self: center; border: 1px solid rgba(240, 201, 106, .38);
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 249, 218, .95) 0 1.2%, transparent 1.5%), radial-gradient(circle, rgba(82, 155, 152, .12), rgba(25, 66, 67, .08) 44%, transparent 70%);
  box-shadow: inset 0 0 70px rgba(69, 151, 147, .12), 0 0 40px rgba(240, 201, 106, .06);
}
.horizon-ring {
  position: absolute; inset: var(--inset);
  border: 1px solid rgba(166, 202, 192, var(--alpha)); border-radius: 50%;
  transition: border-color 180ms ease, background 180ms ease;
}
.horizon::after {
  position: absolute; inset: 2%; border: 1px dashed rgba(240, 201, 106, .24);
  border-radius: 50%; content: "";
}
.lookback-label { color: var(--gold); font: 400 21px/1.25 Georgia, serif; text-align: center; }
.lookback-label span {
  display: block; margin-top: 7px; color: #9faea6;
  font: 11px/1.4 "Trebuchet MS", sans-serif; letter-spacing: .08em; text-transform: uppercase;
}
.horizon-copy { color: #b9c5be; font-size: 13px; }
.horizon-copy strong { display: block; margin-bottom: 8px; color: var(--cream); font: 400 22px Georgia, serif; }
.time-control { display: grid; width: min(100%, 570px); grid-template-columns: 1fr; gap: 7px; }
.time-control label { color: #b8c4bd; font-size: 12px; }
.time-control input { width: 100%; accent-color: var(--gold); cursor: pointer; }
.time-scale { display: flex; justify-content: space-between; color: #738781; font-size: 9px; }
.science-note {
  display: grid; grid-template-columns: .8fr 1.2fr; align-items: center; gap: 36px;
  margin: 36px 0 0; padding: 28px 34px;
  border: 1px solid rgba(240, 201, 106, .24); border-radius: 4px 19px 19px 4px;
  background: rgba(240, 201, 106, .07); box-shadow: inset 5px 0 0 rgba(240, 201, 106, .6);
}
.note-label { margin: 0 0 6px; color: var(--gold); font-size: 10px; font-weight: 700; letter-spacing: .16em; text-transform: uppercase; }
.science-note h2, .sources-card h2 { margin: 0; font: 400 clamp(23px, 2.5vw, 34px)/1.15 Georgia, serif; }
.science-note > p { margin: 0; color: #bdc7c1; }
.page-footer {
  display: flex; min-height: 92px; align-items: center; justify-content: space-between;
  gap: 20px; border-top: 1px solid var(--line); color: #84938e; font-size: 12px;
}
.footer-link { min-height: 44px; padding: 8px 14px; border-radius: 999px; color: #aeb9b2; cursor: pointer; }
.sources-panel {
  position: fixed; z-index: 60; inset: 0; display: grid; place-items: end center;
  padding: 22px; background: rgba(0, 7, 8, .72); backdrop-filter: blur(8px);
}
.sources-card {
  position: relative; width: min(680px, 100%); max-height: min(680px, calc(100vh - 44px));
  overflow: auto; padding: 38px; border: 1px solid #d7cda8;
  border-radius: 8px 25px 25px 8px; background: var(--paper);
  box-shadow: var(--shadow), inset 6px 0 0 var(--gold-deep); color: var(--ink);
}
.close-sources {
  position: absolute; top: 16px; right: 16px; display: grid; width: 42px; height: 42px;
  place-items: center; border: 1px solid rgba(20, 45, 42, .18); border-radius: 50%;
  background: transparent; color: var(--ink); cursor: pointer; font-size: 24px;
}
.sources-card ul { margin: 28px 0 0; padding: 0; list-style: none; }
.sources-card li { border-top: 1px solid rgba(20, 45, 42, .14); }
.sources-card a { display: block; padding: 13px 0; text-underline-offset: 4px; }
.sources-disclaimer { margin: 25px 0 0; color: #5c7068; font-size: 13px; }
.noscript { margin: 20px; padding: 18px; border: 1px solid #d37a5b; background: #fff3dc; color: #263a35; }
@keyframes twinkle { to { opacity: .18; transform: scale(.7); } }
@keyframes earth-turn { to { transform: rotate(360deg); } }
@keyframes orbit-turn { to { transform: rotate(360deg); } }
@keyframes pulse-ring { from { opacity: .8; transform: scale(.55); } to { opacity: 0; transform: scale(1.55); } }
@media (max-width: 980px) {
  .journey-grid { grid-template-columns: 1fr; }
  .story-panel { padding: 42px; border-right: 0; border-bottom: 1px solid rgba(20, 45, 42, .14); }
  .story-panel h1 { font-size: clamp(44px, 8vw, 66px); }
  .cosmos-window { min-height: 590px; }
  .scene { min-height: 420px; }
}
@media (max-width: 720px) {
  .site-header, .page-footer, main { width: min(100% - 24px, 1280px); }
  .site-header { min-height: 82px; }
  main { padding-top: 22px; }
  .brand-orbit { width: 44px; height: 44px; }
  .location-bar { padding: 17px 10px; }
  .step-name { display: none; }
  .story-panel { padding: 34px 25px 32px; }
  .story-panel h1 { font-size: clamp(39px, 13vw, 58px); }
  .essential { font-size: 18px; }
  .detail-item { grid-template-columns: 1fr; gap: 6px; }
  .cosmos-window { min-height: 535px; }
  .scene { min-height: 360px; padding: 23px 15px; }
  .window-label { margin: 20px 18px 0; }
  .solar-scene { overflow-x: auto; padding: 0 10px 8px; scrollbar-color: rgba(240, 201, 106, .4) transparent; }
  .solar-rail { width: 690px; min-height: 250px; }
  .observable-scene { grid-template-columns: 1fr; gap: 10px; }
  .horizon { width: min(290px, 75vw); }
  .horizon-copy { text-align: center; }
  .interaction-card { flex-direction: column; gap: 10px; text-align: center; }
  .interaction-button { width: 100%; }
  .journey-controls { grid-template-columns: 1fr 1fr; padding: 15px; }
  .control-button.secondary { grid-column: 1; }
  .control-button.primary { grid-column: 2; }
  .earth-button { grid-column: 1 / -1; grid-row: 2; justify-self: center; }
  .control-button { width: 100%; justify-content: center; }
  .science-note { grid-template-columns: 1fr; gap: 14px; padding: 25px; }
  .page-footer { flex-direction: column; justify-content: center; padding: 22px 0; }
}
@media (max-width: 430px) {
  body { font-size: 16px; }
  .brand strong { font-size: 16px; }
  .brand small { font-size: 9px; }
  .quiet-button { gap: 6px; padding: 6px 9px; font-size: 12px; }
  .journey-shell { border-radius: 5px 20px 20px 20px; box-shadow: 0 20px 55px rgba(0, 0, 0, .34), inset 5px 0 0 rgba(240, 201, 106, .7); }
  .question-card { grid-template-columns: 36px 1fr; padding: 15px; }
  .question-mark { width: 32px; height: 32px; }
  .earth-scene { width: 290px; }
  .galaxy-scene, .web-scene { width: 300px; }
  .interaction-dock { min-height: 118px; padding: 14px 15px; }
  .control-button { padding: 10px 12px; font-size: 13px; }
  .sources-panel { padding: 10px; }
  .sources-card { padding: 34px 25px 28px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    scroll-behavior: auto !important; animation-duration: .001ms !important;
    animation-iteration-count: 1 !important; transition-duration: .001ms !important;
  }
}
@media (prefers-contrast: more) {
  :root { --line: rgba(255, 248, 223, .48); }
  .story-panel { background: #fff8df; }
}

/* En-tête partagé avec Cérébrine Academy. */
.cerebrine-top{background:#f2eedf;color:#24453d;border-bottom:1px solid #c7d0bd}
.cerebrine-header{max-width:1200px;min-height:116px;margin:auto;padding:25px 30px;display:flex;align-items:center;justify-content:space-between;gap:20px}
.cerebrine-brand{display:flex;align-items:center;gap:10px;color:#24453d;text-decoration:none;font-size:16px;font-weight:bold;white-space:nowrap}
.cerebrine-brand-mascot{display:block;width:64px;height:64px;flex-shrink:0;object-fit:cover;border-radius:50%;border:3px solid #b89a57;box-shadow:0 3px 10px rgba(46,75,64,.14)}
.cerebrine-main-nav{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:8px}
.cerebrine-main-nav a{display:inline-flex;min-height:44px;flex-direction:column;align-items:center;justify-content:center;gap:3px;padding:10px 14px;border:1px solid transparent;border-radius:25px;color:#24453d;text-decoration:none;text-align:center;font-size:14px;line-height:1.25}
.cerebrine-main-nav a:hover{background:#e5eddf}
.cerebrine-main-nav a[aria-current=page]{background:#24453d;color:#fffdf6}
.cerebrine-main-nav .nav-label{font-weight:600}
.cerebrine-main-nav .nav-translation{font-size:10px;line-height:1.2;font-weight:400;opacity:.82}
.universe-toolbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:12px 24px;border-bottom:1px solid var(--line);background:rgba(2,10,11,.52)}
.universe-toolbar p{margin:0;color:#aebcb5;font-size:11px;font-weight:bold;letter-spacing:.1em;text-transform:uppercase}
.universe-toolbar .quiet-button{flex:0 0 auto}
@media(max-width:900px){.cerebrine-header{align-items:flex-start;flex-direction:column}.cerebrine-main-nav{justify-content:flex-start}}
@media(max-width:520px){.cerebrine-header{min-height:auto;padding:19px 20px}.cerebrine-brand{font-size:15px;gap:12px}.cerebrine-brand-mascot{width:56px;height:56px}.cerebrine-main-nav{width:100%;gap:3px}.cerebrine-main-nav a{padding:9px 9px;font-size:12px}.universe-toolbar{padding:10px 14px}.universe-toolbar p{max-width:160px}}