@font-face{font-family:"Literata";font-style:normal;font-weight:300 700;font-display:swap;src:url(fonts/literata-latin.woff2?v=d060c55d) format("woff2");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}
@font-face{font-family:"Literata";font-style:normal;font-weight:300 700;font-display:swap;src:url(fonts/literata-latin-ext.woff2?v=d060c55d) format("woff2");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF}
@font-face{font-family:"Plex Sans";font-weight:400;font-display:swap;src:url(fonts/ibmplexsans-400-lat.woff2?v=d060c55d) format("woff2");unicode-range:U+0000-00FF,U+2000-206F,U+2212}
@font-face{font-family:"Plex Sans";font-weight:400;font-display:swap;src:url(fonts/ibmplexsans-400-ext.woff2?v=d060c55d) format("woff2");unicode-range:U+0100-02FF}
@font-face{font-family:"Plex Sans";font-weight:600;font-display:swap;src:url(fonts/ibmplexsans-600-lat.woff2?v=d060c55d) format("woff2");unicode-range:U+0000-00FF,U+2000-206F,U+2212}
@font-face{font-family:"Plex Sans";font-weight:600;font-display:swap;src:url(fonts/ibmplexsans-600-ext.woff2?v=d060c55d) format("woff2");unicode-range:U+0100-02FF}
@font-face{font-family:"Plex Mono";font-weight:400;font-display:swap;src:url(fonts/ibmplexmono-400-lat.woff2?v=d060c55d) format("woff2");unicode-range:U+0000-00FF,U+2000-206F,U+2212}
@font-face{font-family:"Plex Mono";font-weight:400;font-display:swap;src:url(fonts/ibmplexmono-400-ext.woff2?v=d060c55d) format("woff2");unicode-range:U+0100-02FF}

:root{
  --bg:#f6f1e4;--card:#fffaf0;--ink:#1d1b16;--ink-2:#4d4839;--rule:#dcd3bd;--grid:#e8e0cb;--link:#8a3b00;
  --sun:#b86200;--sun-soft:rgba(232,150,20,.22);--you:#1b4f9c;--you-soft:rgba(27,79,156,.16);--earth:#e9e1cc;--ground:#e3d8bd;--shadow:#3a3326;--bar-bg:rgba(246,241,228,.92);
  --curve:#b86200;color-scheme:light;
}
:root[data-theme="dark"]{--bg:#0f1115;--card:#171a21;--ink:#ece6d8;--ink-2:#bcb5a4;--rule:#2d313b;--grid:#22262f;--link:#ffb870;--sun:#ffb347;--sun-soft:rgba(255,179,71,.2);--you:#8fb8ff;--you-soft:rgba(143,184,255,.18);--earth:#1f232c;--ground:#262219;--shadow:#050608;--bar-bg:rgba(15,17,21,.9);--curve:#ffb347;color-scheme:dark}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){--bg:#0f1115;--card:#171a21;--ink:#ece6d8;--ink-2:#bcb5a4;--rule:#2d313b;--grid:#22262f;--link:#ffb870;--sun:#ffb347;--sun-soft:rgba(255,179,71,.2);--you:#8fb8ff;--you-soft:rgba(143,184,255,.18);--earth:#1f232c;--ground:#262219;--shadow:#050608;--bar-bg:rgba(15,17,21,.9);--curve:#ffb347;color-scheme:dark}}

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:400 1.125rem/1.62 "Literata",Georgia,serif;overflow-x:hidden}
a{color:var(--link);text-underline-offset:.18em;text-decoration-thickness:1px}
:focus-visible{outline:3px solid var(--curve);outline-offset:3px;border-radius:4px}
b,strong{font-weight:640}
[hidden]{display:none!important}
html:not(.js) .js-only{display:none!important}
.nojs-note{display:none}
html:not(.js) .nojs-note{display:block}
.skip{position:absolute;left:-999px;top:0;background:var(--card);color:var(--ink);padding:.5rem .8rem;z-index:99}
.skip:focus{left:.5rem;top:.5rem}
section[id]{scroll-margin-top:3.5rem}

/* ---- top bar ---- */
.topbar{position:sticky;top:0;z-index:40;display:flex;align-items:center;gap:.9rem;height:2.75rem;padding:0 1rem;background:var(--bar-bg);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);border-bottom:1px solid var(--rule);font:400 .9rem/1 "Plex Sans",system-ui,sans-serif}
.topbar a{color:var(--ink);text-decoration:none}
.topbar .home{font-weight:600;white-space:nowrap}
.topnav{display:flex;gap:1rem;overflow-x:auto;scrollbar-width:none;min-width:0;flex:0 1 auto}
.topnav::-webkit-scrollbar{display:none}
.topnav a{white-space:nowrap;color:var(--ink-2)}
.topnav a:hover,.topnav a[aria-current="true"]{color:var(--ink);text-decoration:underline}
.spacer{flex:1 1 0}
.chip{position:relative;border:1px solid var(--ink-2);border-radius:99px;padding:.25rem .7rem;font-size:.82rem;white-space:nowrap}
.chip::after{content:"";position:absolute;left:-4px;right:-4px;top:50%;height:44px;transform:translateY(-50%)}
.icon-btn{display:inline-grid;place-items:center;width:2.75rem;height:2.75rem;margin-right:-.6rem;background:none;border:0;color:var(--ink);cursor:pointer;border-radius:50%}
.icon-btn svg[hidden]{display:none}
@media (max-width:760px){.topnav{display:none}.topbar{gap:.6rem}}

/* ---- rail ---- */
.rail{position:fixed;right:.9rem;top:50%;transform:translateY(-50%);z-index:30;display:flex;flex-direction:column;gap:.55rem;font-family:"Plex Sans",system-ui,sans-serif}
.rail a{display:flex;align-items:center;justify-content:flex-end;gap:.5rem;text-decoration:none;color:var(--ink-2);font-size:.8rem;min-height:24px}
.rail a span{opacity:0;transform:translateX(6px);transition:opacity .2s,transform .2s;background:var(--card);border:1px solid var(--rule);color:var(--ink);padding:.1rem .5rem;border-radius:4px;white-space:nowrap}
.rail a:hover span,.rail a:focus-visible span{opacity:1;transform:none}
.rail i{width:8px;height:8px;border-radius:50%;border:1.5px solid var(--ink-2);flex:none;transition:background .2s,transform .2s}
.rail a[aria-current="true"] i{background:var(--curve);border-color:var(--curve);transform:scale(1.35)}
@media (max-width:1100px){.rail{display:none}}

/* ---- page ---- */
main{padding:0 1rem}
article{max-width:68rem;margin:0 auto}
article{max-width:68rem;margin:0 auto}
.vh{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}

/* ---- hero ---- */
.hero{padding:1.8rem 0 1rem;max-width:68rem;margin:0 auto}
h1{font-weight:640;font-size:clamp(2.1rem,6vw,4.2rem);line-height:1.02;letter-spacing:-.018em;margin:0 0 .9rem;max-width:16ch;text-wrap:balance}
.deck{font-size:clamp(1.08rem,1.8vw,1.32rem);color:var(--ink-2);max-width:40rem;margin:0 0 1.3rem}
.today{font:400 1rem/1.45 "Plex Sans",system-ui,sans-serif;background:var(--card);border:1px solid var(--rule);border-radius:14px;padding:.9rem 1rem;max-width:40rem}
.place{display:flex;flex-wrap:wrap;align-items:baseline;gap:.2rem .6rem}
.place-name{font-weight:600;font-size:1.15rem}
.place-how{color:var(--ink-2);font-size:.88rem}
.noon{font:400 clamp(1.25rem,3.2vw,1.7rem)/1.3 "Literata",Georgia,serif;margin:.5rem 0 .2rem}
.noon b{color:var(--sun);font-variant-numeric:tabular-nums}
.count{margin:0;font-weight:600;color:var(--ink)}
.window{margin:.3rem 0 0;color:var(--ink-2);font-size:.92rem}
.static-noon{font-size:1.02rem;color:var(--ink-2);max-width:40rem}
.link-btn{background:none;border:0;padding:.5rem .1rem;min-height:44px;font:inherit;font-size:.92rem;color:var(--link);text-decoration:underline;cursor:pointer}
.picker{margin:.4rem 0 0}
.picker input{width:100%;font:400 1.05rem "Plex Sans",system-ui,sans-serif;min-height:44px;padding:.4rem .7rem;border:1.5px solid var(--rule);border-radius:8px;background:var(--bg);color:var(--ink)}
#hits{list-style:none;padding:0;margin:.3rem 0 0}
#hits button{display:block;width:100%;text-align:left;min-height:44px;padding:.4rem .6rem;background:none;border:0;border-bottom:1px solid var(--rule);font:inherit;color:var(--ink);cursor:pointer}
#hits button:hover,#hits button:focus-visible{background:var(--sun-soft)}
.scene{margin:1rem 0 0;max-width:46rem}
#scene{display:block;width:100%;height:auto}
.ground{fill:var(--ground)}
.horizon{stroke:var(--ink-2);stroke-width:1}
.ray{stroke:var(--sun);stroke-width:1.2;opacity:.55}
.ray.key{opacity:1;stroke-width:2}
.shadow{fill:var(--shadow);opacity:.75}
.pencil{fill:#e0a526;stroke:var(--ink);stroke-width:1}
.tip{fill:var(--ink)}
.arc{fill:none;stroke:var(--you);stroke-width:2}
.lbl{font:400 15px "Plex Sans",system-ui,sans-serif;fill:var(--ink);paint-order:stroke;stroke:var(--bg);stroke-width:4px;stroke-linejoin:round}
.lbl.small{font-size:13px}
.lbl.end{text-anchor:end}
.lbl.mid{text-anchor:middle}

/* ---- blocks ---- */
.block{max-width:68rem;margin:0 auto;padding:2.8rem 0 1rem;border-top:1px solid var(--rule)}
.block > h2,.block > p,.block > ol,.block > ul,.block > h3,.block > form,.block > .note{max-width:40rem}
h2{font-size:clamp(1.5rem,2.8vw,2.05rem);line-height:1.16;margin:0 0 1rem;font-weight:620;text-wrap:balance}
h2 .anchor{color:inherit;text-decoration:none}
h2 .anchor:hover{text-decoration:underline}
h3{font:600 1.1rem "Plex Sans",system-ui,sans-serif;margin:1.8rem 0 .7rem}
p{margin:0 0 1rem}
.note{font-size:.97rem;color:var(--ink-2)}
.small{font-size:.95rem;color:var(--ink-2)}
.steps{padding-left:1.4rem;margin:0 0 1.4rem}
.steps li{margin-bottom:.8rem;padding-left:.2rem}
.steps li::marker{font:600 1.1rem "Plex Sans",system-ui,sans-serif;color:var(--sun)}
.plan{padding-left:1.4rem}
.plan li{margin-bottom:.8rem}
.nots{padding-left:1.2rem}
.nots li{margin-bottom:.9rem}

/* ---- lab ---- */
.lab,.class-lab{background:var(--card);border:1px solid var(--rule);border-radius:14px;padding:1rem;margin:0 0 1rem;font-family:"Plex Sans",system-ui,sans-serif}
.fields{display:flex;flex-wrap:wrap;gap:.8rem 1rem;align-items:flex-end}
.fields label{display:flex;flex-direction:column;gap:.25rem;font-size:.9rem;color:var(--ink-2)}
.fields input{font:600 1.5rem/1 "Plex Mono",ui-monospace,monospace;width:7ch;min-height:3rem;padding:.35rem .55rem;border:2px solid var(--rule);border-bottom-width:5px;border-radius:8px;background:var(--bg);color:var(--ink)}
.fields input[type=time]{width:auto;font-size:1.2rem}
.fields input:focus{outline:none;border-color:var(--sun)}
.tol{border:0;padding:0;margin:.9rem 0 0;display:flex;flex-wrap:wrap;gap:.2rem 1rem;font-size:.92rem;color:var(--ink-2)}
.tol legend{padding:0;margin-bottom:.3rem;flex-basis:100%}
.tol label{display:inline-flex;align-items:center;gap:.35rem;min-height:44px;color:var(--ink)}
.tol input{width:1.15rem;height:1.15rem;accent-color:var(--sun)}
.readout{font:400 1.08rem/1.5 "Plex Sans",system-ui,sans-serif;margin:.9rem 0 0}
.readout b{color:var(--you)}
.btn{min-height:44px;padding:.5rem 1.1rem;border-radius:99px;border:1.5px solid var(--sun);background:var(--sun);color:#fff;font:600 .98rem "Plex Sans",system-ui,sans-serif;cursor:pointer}
:root[data-theme="dark"] .btn{color:#1a1206}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]) .btn{color:#1a1206}}
.btn.ghost{background:transparent;color:var(--ink);border-color:var(--rule)}
.btn.ghost[aria-pressed="true"]{border-color:var(--sun);box-shadow:inset 0 0 0 1px var(--sun)}
.actions{display:flex;flex-wrap:wrap;gap:.6rem;margin:1rem 0 .6rem}

/* ---- two columns: prose beside its figure ---- */
.duo{display:grid;gap:1.4rem}
.duo .prose{max-width:40rem}
@media (min-width:980px){.duo{grid-template-columns:minmax(0,40rem) minmax(0,1fr);gap:2.6rem;align-items:start}.duo .globe{position:sticky;top:4rem}}
.globe{margin:0}
.globe svg{display:block;width:100%;max-width:30rem;height:auto;margin:0 auto}
.earth{fill:var(--earth);stroke:var(--ink-2);stroke-width:1.2}
.earth.ghost{fill:none;stroke:var(--ink-2);stroke-dasharray:4 5}
.earth.mine{fill:var(--you-soft);stroke:var(--you);stroke-width:2.2}
.bandring{fill:none;stroke:var(--you);stroke-width:1;stroke-dasharray:2 4;opacity:.8}
.eq{stroke:var(--ink-2);stroke-width:1;stroke-dasharray:3 4}
.radius{stroke:var(--ink-2);stroke-width:1.3}
.radius.you{stroke:var(--you);stroke-width:2}
.band{fill:var(--you-soft);stroke:none}
.pen{stroke:#e0a526;stroke-width:5;stroke-linecap:round}
.dot{fill:var(--ink)}
.dot.you{fill:var(--you);stroke:var(--card);stroke-width:2}
.dot.sun{fill:var(--sun)}
.dot.far{fill:var(--ink-2);opacity:.5}
.result{margin:1.2rem 0;padding:1rem 1.1rem;border-left:4px solid var(--you);background:var(--card);border-radius:0 12px 12px 0;font-family:"Plex Sans",system-ui,sans-serif;font-size:1rem}
.result:empty{display:none}
.result .big{font:400 1.3rem/1.4 "Literata",Georgia,serif}
.result .big b{color:var(--you)}
.result .warn,.warn{color:var(--link)}
.result p:last-child{margin-bottom:0}
.wait{color:var(--ink-2)}

/* ---- class ---- */
#strip{display:block;width:100%;height:auto;margin:1rem 0 0}
.axis{stroke:var(--ink-2);stroke-width:1}
.townline{stroke:var(--ink-2);stroke-width:1;stroke-dasharray:3 3}
.median{stroke:var(--you);stroke-width:3}
.rows{list-style:none;padding:0;margin:.6rem 0;font-size:.95rem}
.rows li{border-bottom:1px solid var(--rule);display:flex;justify-content:space-between;align-items:center;gap:.6rem;font-variant-numeric:tabular-nums}

/* ---- stade bars ---- */
.bars{margin:0 0 1.4rem;max-width:44rem;font:400 .95rem "Plex Sans",system-ui,sans-serif}
.bar{display:grid;grid-template-columns:minmax(0,15rem) minmax(0,1fr) auto;gap:.3rem .8rem;align-items:center;padding:.45rem 0}
.bt{display:block;width:100%;height:14px}
.bt .track{fill:var(--grid)}
.bt .fill{fill:var(--sun)}
.bar.truth .bt .fill{fill:var(--you)}
.bar.truth{font-weight:600}
.bv{font-variant-numeric:tabular-nums;white-space:nowrap}
.bars figcaption{color:var(--ink-2);font-size:.88rem;margin-top:.5rem}
@media (max-width:620px){.bar{grid-template-columns:1fr auto}.bt{grid-column:1/-1;grid-row:2}}
.end{font-size:1.22rem;line-height:1.5;margin-top:2rem;padding-top:1.4rem;border-top:1px solid var(--rule)}
.more{padding-left:1.1rem}
.more li{margin-bottom:.6rem}

/* ---- sources, footer ---- */
.method{font-size:.97rem;color:var(--ink-2);max-width:40rem}
.srcs{font-size:.88rem;color:var(--ink-2);padding-left:1.1rem;max-width:40rem}
.srcs li{margin-bottom:.35rem;overflow-wrap:anywhere}
.foot{max-width:40rem;margin:3rem auto 0;padding:1.5rem 1rem 3rem;border-top:1px solid var(--rule);font:400 .9rem "Plex Sans",system-ui,sans-serif;color:var(--ink-2)}
.nf main{max-width:40rem;margin:4rem auto;padding:0 1rem}
.totop{position:fixed;right:1rem;bottom:1rem;z-index:35;display:grid;place-items:center;width:44px;height:44px;border-radius:50%;background:var(--card);border:1px solid var(--rule);color:var(--ink);text-decoration:none;font:600 1.1rem "Plex Sans",system-ui,sans-serif;box-shadow:0 2px 8px rgba(0,0,0,.15)}
@media (min-width:1101px){.totop{display:none}}
@media (prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}
/* On a classroom projector, bigger is better: the numbers the class reads together. */
@media (min-width:1400px){.noon{font-size:2rem}.result .big{font-size:1.5rem}body{font-size:1.2rem}}
.count:empty{display:none}
:root .btn.ghost,:root[data-theme="dark"] .btn.ghost{color:var(--ink)}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]) .btn.ghost{color:var(--ink)}}
html:not(.js) .scene,html:not(.js) .globe,html:not(.js) #strip{display:none}