html{scroll-padding-top:env(safe-area-inset-top,0px)}
body{margin:0}
img{max-width:100%}
[hidden]{display:none!important}
/* Layout: three glass planets above one question panel, with a narrow three-step orbit rail on the left. */
:root{
 --ml-ground:#EEF3FC;--ml-surface:#FFFFFF;--ml-surface-2:#E3EBF9;--ml-line:#CBD6EA;
 --ml-ink:#101B33;--ml-ink-soft:#47546C;--ml-accent:#2160E0;--ml-on-accent:#FFFFFF;
 --ml-highlight:#DCE8FE;--ml-on-highlight:#123A8C;--ml-code-bg:#101B33;--ml-code-ink:#BCE6FF;
 --ml-radius:999px;--ml-radius-lg:28px;--ml-depth:0;
 --ml-font-display:-apple-system,BlinkMacSystemFont,"SF Pro Display","Segoe UI",Roboto,Helvetica,Arial,sans-serif;
 --ml-font-text:-apple-system,BlinkMacSystemFont,"SF Pro Text","Segoe UI",Roboto,Helvetica,Arial,sans-serif;
 --ml-font-code:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
 --ml-logo-ink:#101B33;--ml-logo-satellite:#FFC600;--ml-logo-planet:#EEF3FC;--ml-logo-rim:#00A9FF;
}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){
 --ml-ground:#0B1222;--ml-surface:#141E33;--ml-surface-2:#1C2842;--ml-line:#2F3D5C;
 --ml-ink:#EDF2FC;--ml-ink-soft:#A8B4CB;--ml-accent:#7FA9FF;--ml-on-accent:#0B1222;
 --ml-highlight:#1E3263;--ml-on-highlight:#D9E5FF;--ml-code-bg:#050A14;--ml-code-ink:#BCE6FF;
 --ml-logo-ink:#EDF2FC;--ml-logo-planet:#0B1222;color-scheme:dark;}}
:root[data-theme="dark"]{
 --ml-ground:#0B1222;--ml-surface:#141E33;--ml-surface-2:#1C2842;--ml-line:#2F3D5C;
 --ml-ink:#EDF2FC;--ml-ink-soft:#A8B4CB;--ml-accent:#7FA9FF;--ml-on-accent:#0B1222;
 --ml-highlight:#1E3263;--ml-on-highlight:#D9E5FF;--ml-code-bg:#050A14;--ml-code-ink:#BCE6FF;
 --ml-logo-ink:#EDF2FC;--ml-logo-planet:#0B1222;color-scheme:dark;}
*{box-sizing:border-box}
html{height:100%;-webkit-text-size-adjust:100%}
body{min-height:100%;background:var(--ml-ground);color:var(--ml-ink);font:400 16px/1.5 var(--ml-font-text);font-synthesis:none;-webkit-font-smoothing:antialiased}
button{font:inherit;color:inherit;cursor:pointer}
a{color:var(--ml-accent)}
a:focus-visible,button:focus-visible,summary:focus-visible,[tabindex]:focus-visible{outline:3px solid var(--ml-ink);outline-offset:3px}
h2[tabindex]:focus,h2[tabindex]:focus-visible{outline:none}
.vh{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
.app{position:relative;isolation:isolate;min-height:100vh;display:grid;grid-template-rows:auto 1fr auto;overflow-x:clip;
 background:radial-gradient(90% 60% at 50% 34%,color-mix(in srgb,var(--ml-accent) 12%,transparent),transparent 72%),var(--ml-ground)}
.wrap{padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px))}
.waves{position:absolute;inset:auto 0 56px;height:38vh;width:100%;z-index:-1;pointer-events:none}
.waves path:nth-child(1){fill:color-mix(in srgb,var(--ml-accent) 9%,transparent)}
.waves path:nth-child(2){fill:color-mix(in srgb,lavender 16%,color-mix(in srgb,var(--ml-accent) 12%,transparent))}
.waves path:nth-child(3){fill:color-mix(in srgb,var(--ml-accent) 14%,transparent)}

.top{display:flex;align-items:center;justify-content:space-between;gap:12px;padding-block:18px 0;max-width:1200px;width:100%;margin-inline:auto}
.brand{display:flex;align-items:center;gap:10px;font:600 16px/1.2 var(--ml-font-display);color:var(--ml-ink);text-decoration:none}
.theme{display:flex;gap:2px;padding:3px;border-radius:999px;background:color-mix(in srgb,var(--ml-surface) 70%,transparent);border:1px solid var(--ml-line)}
.theme button{display:grid;place-items:center;width:32px;height:30px;border:0;border-radius:999px;background:none;color:var(--ml-ink-soft)}
.theme button[aria-pressed="true"]{background:var(--ml-surface);color:var(--ml-ink);box-shadow:0 1px 3px color-mix(in srgb,var(--ml-ink) 18%,transparent)}
.theme svg{width:17px;height:17px}

main{min-width:0;padding-block:6px 28px}
.title{text-align:center}
h1{font:700 clamp(25px,3.4vw,34px)/1.15 var(--ml-font-display);letter-spacing:-.018em;margin:0;text-wrap:balance}
.title p{margin:6px 0 0;color:var(--ml-ink-soft)}
.layout{display:grid;grid-template-columns:minmax(88px,11%) minmax(0,1fr) minmax(0,11%);max-width:1200px;margin-inline:auto;align-items:start}

/* Three-step rail */
.steps{list-style:none;margin:0;padding:40px 0 0;display:flex;flex-direction:column;align-items:center;gap:30px}
.step{position:relative;display:grid;justify-items:center;gap:6px;font-size:13px;color:var(--ml-ink-soft)}
.step+.step::before{content:"";position:absolute;top:-30px;left:50%;height:30px;width:1px;background:var(--ml-line)}
.bubble{display:grid;place-items:center;width:64px;height:64px;border-radius:50%;background:color-mix(in srgb,var(--ml-surface) 70%,transparent);border:1px solid var(--ml-line);color:var(--ml-ink-soft);text-align:center;font:600 12px/1.1 var(--ml-font-text);padding:4px;overflow-wrap:anywhere}
.bubble svg{width:24px;height:24px}
.step.current .bubble{background:var(--ml-accent);border-color:var(--ml-accent);color:var(--ml-on-accent);box-shadow:0 8px 22px color-mix(in srgb,var(--ml-accent) 32%,transparent)}
.step.current{color:var(--ml-ink);font-weight:600}
.step.done .bubble{background:var(--ml-surface);color:var(--ml-ink);border-color:var(--ml-accent)}
.step.skip .bubble{border-style:dashed;background:none}

/* Planets */
#stage{position:relative;height:clamp(290px,46vh,430px);margin-top:4px}
.orbits{position:absolute;inset:0;width:100%;height:100%;overflow:visible;pointer-events:none}
.orbits ellipse{fill:none;stroke:color-mix(in srgb,var(--ml-accent) 34%,transparent);stroke-width:1;vector-effect:non-scaling-stroke}
.orbits circle{fill:var(--ml-accent)}
.orb{position:absolute;top:50%;left:50%;display:grid;place-items:center;align-content:center;gap:2px;border-radius:50%;text-align:center;animation:float 7s ease-in-out infinite}
.orb b{font:700 1.45em/1.1 var(--ml-font-display)}
.orb .name{display:block;max-width:76%;font-weight:600;line-height:1.2;transition:opacity .2s;overflow-wrap:anywhere}
.orb1{--x:-50%;--y:-50%;z-index:3;width:clamp(200px,38vh,330px);height:clamp(200px,38vh,330px);font-size:clamp(15px,2.5vh,20px);color:white;
 background:radial-gradient(38% 30% at 34% 20%,color-mix(in srgb,white 58%,transparent),transparent),radial-gradient(90% 62% at 50% -6%,color-mix(in srgb,white 26%,transparent),transparent),radial-gradient(circle at 50% 62%,color-mix(in srgb,royalblue 74%,navy) 0,color-mix(in srgb,royalblue 62%,navy) 58%,color-mix(in srgb,royalblue 88%,white) 100%);
 box-shadow:inset 0 -18px 42px color-mix(in srgb,white 28%,transparent),inset 0 8px 24px color-mix(in srgb,white 24%,transparent),0 26px 54px color-mix(in srgb,royalblue 34%,transparent)}
.orb2,.orb3{z-index:2;width:clamp(110px,21vh,180px);height:clamp(110px,21vh,180px);font-size:clamp(12px,1.75vh,15px);color:var(--ml-ink);
 background:radial-gradient(44% 34% at 34% 24%,color-mix(in srgb,var(--ml-surface) 86%,transparent),transparent),radial-gradient(circle at 50% 55%,color-mix(in srgb,var(--ml-surface) 78%,transparent) 0,color-mix(in srgb,var(--ml-surface-2) 86%,transparent) 66%,color-mix(in srgb,var(--ml-accent) 34%,var(--ml-surface)) 100%);
 border:1px solid color-mix(in srgb,var(--ml-surface) 46%,transparent);box-shadow:inset 0 -10px 22px color-mix(in srgb,var(--ml-accent) 16%,transparent),0 14px 30px color-mix(in srgb,var(--ml-accent) 14%,transparent);backdrop-filter:blur(6px)}
.orb2{--x:calc(-50% + clamp(170px,23vw,270px));--y:-58%;animation-delay:-2.5s}
.orb3{--x:calc(-50% - clamp(170px,23vw,270px));--y:-44%;animation-delay:-5s}
.orb2 b,.orb3 b{font-size:1.2em}
@keyframes float{0%,100%{transform:translate(var(--x),var(--y))}50%{transform:translate(var(--x),calc(var(--y) - 7px))}}
.orb{transform:translate(var(--x),var(--y))}

/* Question panel */
.panel{position:relative;z-index:4;width:min(660px,100%);margin:8px auto 0;padding:22px 24px 16px;text-align:center;border-radius:var(--ml-radius-lg);border:1px solid color-mix(in srgb,var(--ml-surface) 60%,var(--ml-line));background:color-mix(in srgb,var(--ml-surface) 72%,transparent);backdrop-filter:blur(18px);box-shadow:0 18px 44px color-mix(in srgb,var(--ml-accent) 12%,transparent)}
.panel.wide{width:min(760px,100%);text-align:left}
h2{font:700 clamp(20px,2.6vw,23px)/1.2 var(--ml-font-display);letter-spacing:-.012em;margin:0;text-wrap:balance}
.help{margin:4px 0 0;color:var(--ml-ink-soft);font-size:16px}
.opts{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;margin-top:14px}
.opt{display:flex;align-items:center;justify-content:center;gap:8px;flex:0 1 calc(33.33% - 7px);min-height:46px;padding:9px 14px;border-radius:var(--ml-radius);border:1px solid var(--ml-line);background:color-mix(in srgb,var(--ml-surface-2) 62%,transparent);font-size:15px;line-height:1.2;transition:background .15s,border-color .15s}
.n4 .opt{flex-basis:calc(50% - 5px)}
.opt svg{flex:none;width:18px;height:18px}
.opt:hover{border-color:var(--ml-accent);background:var(--ml-surface)}
.opt[aria-pressed="true"]{background:var(--ml-highlight);border-color:var(--ml-accent);color:var(--ml-on-highlight);font-weight:600}
.foot{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-top:12px;min-height:36px;font-size:14px;color:var(--ml-ink-soft)}
.link{background:none;border:0;padding:8px 2px;color:var(--ml-accent);font-size:14px}

/* Result inside the same panel */
.rows{margin:12px 0 0;display:grid;gap:0}
.rows>div{display:grid;grid-template-columns:104px minmax(0,1fr);gap:4px 16px;padding-block:9px;border-top:1px solid var(--ml-line)}
.rows dt{color:var(--ml-ink-soft);font-size:14px;padding-top:1px}
.rows dd{margin:0;min-width:0}
.rows strong{font-weight:600}
.soft{color:var(--ml-ink-soft)}
.notes{margin:10px 0 0;padding:10px 14px;border-radius:16px;background:var(--ml-surface-2);font-size:16px;display:grid;gap:6px}
.notes p{margin:0}
.ctrl{display:flex;flex-wrap:wrap;gap:8px;margin-top:14px}
.ctrl .opt{flex:0 1 auto;min-height:42px;padding-inline:16px}
.extra{margin-top:10px;font-size:16px}
.extra p{margin:6px 0 0}
.extra:empty{display:none}
details{margin-top:12px;border-top:1px solid var(--ml-line);padding-top:8px}
summary{cursor:pointer;color:var(--ml-accent);font-size:15px;padding-block:4px}
details h3{font:600 15px/1.3 var(--ml-font-display);margin:12px 0 4px}
details ol,details ul{margin:0;padding-left:20px;display:grid;gap:3px;font-size:16px}
.scroll{overflow-x:auto}
table{border-collapse:collapse;width:100%;font-size:14px;font-variant-numeric:tabular-nums}
th,td{padding:6px 10px 6px 0;text-align:left;border-bottom:1px solid var(--ml-line);vertical-align:top}
.n{text-align:right;white-space:nowrap}
.src{display:block;font-size:14px;color:var(--ml-ink-soft)}

.right{display:flex;align-items:center;gap:14px}
.hlink{font-size:15px;color:var(--ml-ink);text-underline-offset:3px}
.how{position:relative;z-index:4;width:min(840px,100%);margin:18px auto 0;padding:24px clamp(16px,4vw,36px) 26px;border-radius:var(--ml-radius-lg);border:1px solid color-mix(in srgb,var(--ml-surface) 60%,var(--ml-line));background:color-mix(in srgb,var(--ml-surface) 86%,transparent);backdrop-filter:blur(18px)}
.how h2{font-size:clamp(25px,3.4vw,32px);margin-top:6px}
.how h3{font:600 19px/1.3 var(--ml-font-display);margin:26px 0 6px}
.how p{margin:8px 0 0;max-width:68ch}
.how ul{margin:8px 0 0;padding-left:20px;display:grid;gap:5px;max-width:68ch}
.how figure{margin:12px 0 0}
.how figcaption{margin-top:6px;color:var(--ml-ink-soft)}
.how .scroll svg{display:block;min-width:640px;width:100%;height:auto}
.how .scroll table{min-width:620px}
.how th{font-weight:600}
.back{display:inline-block;font-size:15px}
.tb{fill:none;stroke:var(--ml-ink-soft);stroke-width:1.25}
.te{fill:var(--ml-surface-2);stroke:var(--ml-ink-soft);stroke-width:1.25}
.tm{fill:var(--ml-highlight);stroke:var(--ml-accent);stroke-width:2}
.tl{fill:none;stroke:var(--ml-ink-soft);stroke-width:1.25}
.ta{fill:var(--ml-ink-soft)}
.tn{fill:var(--ml-ink);font:600 13px var(--ml-font-text);text-anchor:middle}
.ts{fill:var(--ml-ink-soft);font:400 11.5px var(--ml-font-text);text-anchor:middle}
footer{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:6px 20px;padding-block:12px;background:var(--ml-ground);font-size:13px;color:var(--ml-ink-soft)}
footer .by{display:flex;align-items:center;gap:10px}
footer .none{margin:0;max-width:88ch}

@media (max-width:860px){
 .layout{grid-template-columns:minmax(0,1fr)}
 .layout>.gap{display:none}
 .steps{flex-direction:row;justify-content:center;gap:34px;padding:12px 0 0}
 .step+.step::before{top:27px;left:-34px;width:34px;height:1px}
 .bubble{width:54px;height:54px;font-size:11px}
 .bubble svg{width:20px;height:20px}
 .orb2{--x:calc(-50% + 31vw)}
 .orb3{--x:calc(-50% - 31vw)}
}
@media (max-width:560px){
 #stage{height:250px}
 .orb1{width:172px;height:172px;font-size:14px}
 .orb2,.orb3{width:104px;height:104px;font-size:11.5px}
 .orb2 .name,.orb3 .name{max-width:82%}
 .orb2{--x:calc(-50% + 29vw);--y:-82%}
 .orb3{--x:calc(-50% - 29vw);--y:-18%}
 .panel{padding:18px 16px 12px}
 .opt,.n4 .opt{flex-basis:100%;justify-content:flex-start}
 .ctrl .opt{flex-basis:100%;justify-content:center}
 .rows>div{grid-template-columns:minmax(0,1fr)}
 .waves{height:30vh}
}
@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}
.ml-logo .ring{fill:none;stroke:var(--ml-logo-ink);stroke-width:34;stroke-linecap:round}
.ml-logo .gring{fill:none;stroke-width:34;stroke-linecap:round}
.ml-logo .sat{fill:var(--ml-logo-satellite)}
.ml-logo .m{fill:var(--ml-logo-ink)}
.ml-logo .planet{fill:var(--ml-logo-planet)}
.ml-logo .rim{fill:none;stroke:var(--ml-logo-rim);stroke-width:18}
.s-light{stop-color:color-mix(in srgb,var(--ml-accent) 45%,white)}
.s-mid{stop-color:color-mix(in srgb,var(--ml-accent) 78%,white)}
.s-accent{stop-color:var(--ml-accent)}
.s-glow{stop-color:var(--ml-logo-rim);stop-opacity:.34}
.s-fade{stop-color:var(--ml-logo-rim);stop-opacity:0}