/* ── Aether Cosmology Research Group — Stellar Aberration sim ───────────── */

:root{
  --accent:#45b8e6;          /* ACRG blue */
  --star:#f2c14e;            /* true star / incoming ray */
  --app:#3fe0d0;            /* apparent / refracted ray */
  --vel:#ff5b6a;            /* velocity vector */
  --panel:rgba(12,18,30,.82);
  --edge:rgba(69,184,230,.35);
  --ink:#e9eef6;
  --dim:#9fb0c6;
}

*{box-sizing:border-box;margin:0}
html,body{height:100%;overflow:hidden;background:#05070d;color:var(--ink);
  font:14px/1.5 system-ui,-apple-system,Segoe UI,Roboto,sans-serif}

#scene{position:fixed;inset:0;width:100%;height:100%;display:block}

/* Glass panels */
.panel{position:fixed;z-index:2;width:330px;padding:16px 18px;
  background:var(--panel);border:1px solid var(--edge);border-radius:14px;
  backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
  box-shadow:0 10px 40px rgba(0,0,0,.5)}
#panel{top:16px;left:16px;width:360px;max-height:calc(100vh - 32px);overflow-y:auto}
.div{border:none;border-top:1px solid var(--edge);margin:18px 0 2px}
.panel h2{font-size:15px;margin-bottom:10px;color:#fff}
#desc{font-size:12.5px;color:var(--dim);margin:10px 0 14px}

/* Theory selector */
label.sel{display:block;font-size:12.5px;color:var(--dim)}
#theory,#view{width:100%;margin-top:6px;padding:8px 10px;border-radius:9px;
  background:#0e1726;color:#fff;border:1px solid var(--edge);font-size:13px;cursor:pointer}
#row-view{margin-bottom:14px}

/* Frame toggle */
#frame-wrap{margin-bottom:14px}
.toggle{display:flex;gap:6px}
.toggle button{flex:1;padding:8px 0;border:1px solid var(--edge);border-radius:9px;
  background:transparent;color:var(--dim);font-weight:600;font-size:12.5px;cursor:pointer;transition:.15s}
.toggle button:hover{color:#fff;border-color:var(--accent)}
.toggle button.active{background:var(--accent);color:#04121b;border-color:var(--accent)}

/* Sliders */
label{display:block;font-size:12.5px;color:var(--dim);margin-bottom:14px}
label b{color:#fff}
input[type=range]{-webkit-appearance:none;appearance:none;width:100%;height:4px;margin-top:8px;
  border-radius:3px;background:#26364c;outline:none}
input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;width:15px;height:15px;
  border-radius:50%;background:var(--accent);cursor:pointer;box-shadow:0 0 8px var(--accent)}
input[type=range]::-moz-range-thumb{width:15px;height:15px;border:none;border-radius:50%;
  background:var(--accent);cursor:pointer}
.check{display:flex;align-items:center;gap:8px}
.check input{accent-color:var(--accent)}

/* Colour key */
.key{list-style:none;display:flex;flex-wrap:wrap;gap:6px 14px;margin-top:4px;font-size:12px}
.key li{display:flex;align-items:center;gap:6px}
.dot{width:9px;height:9px;border-radius:50%}
.dot.star{background:var(--star)} .dot.app{background:var(--app)} .dot.vel{background:var(--vel)}

/* Source link */
.src{margin-top:14px;font-size:12px;color:var(--dim)}
.src a{color:var(--accent);text-decoration:none;font-weight:600}
.src a:hover{text-decoration:underline}

/* Math legend */
#panel .row{display:flex;justify-content:space-between;font-size:12.5px;padding:2px 0}
#panel .row span{color:var(--dim)} #panel .row b{color:#fff;font-variant-numeric:tabular-nums}
.formula{font:12.5px/1.6 ui-monospace,Menlo,Consolas,monospace;color:var(--app);
  background:rgba(63,224,208,.07);border-radius:8px;padding:8px 10px;white-space:pre-wrap;margin-bottom:10px}
.equal{margin:6px 0;font-size:12.5px;color:#fff;text-align:center;
  background:rgba(69,184,230,.1);border-radius:8px;padding:7px}
.equal .ok{color:#5fd07a} .equal .bad{color:#ff6a78}
/* Micrometer-scale numerics block */
.scale{margin-top:10px;padding:8px 10px;border:1px solid var(--edge);border-radius:8px;
  background:rgba(69,184,230,.06)}
.scale .sh{font-size:11px;font-weight:700;color:var(--accent);margin-bottom:4px;letter-spacing:.2px}
.scale .r{display:flex;justify-content:space-between;font-size:12px;padding:1px 0}
.scale .r span{color:var(--dim)} .scale .r b{color:#fff;font-variant-numeric:tabular-nums}
.scale .r.hit b{color:#5fd07a}

.note{margin-top:10px;font-size:11.5px;color:var(--dim)}

/* “What does reading mean” collapsible */
.help{margin-top:10px;font-size:11.5px}
.help summary{cursor:pointer;color:var(--star);font-weight:700;list-style:none}
.help summary::-webkit-details-marker{display:none}
.help summary::before{content:'▸ ';color:var(--star)}
.help[open] summary::before{content:'▾ '}
.help p{margin-top:7px;color:var(--dim)} .help b{color:#dbe6f4}

/* Micrometer conversion panel (right sector) */
#micro-panel{position:fixed;z-index:2;right:24px;top:50%;transform:translateY(-50%);
  width:372px;max-height:calc(100vh - 32px);overflow-y:auto;padding:20px 22px;
  background:var(--panel);border:1px solid var(--edge);border-radius:14px;
  backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
  box-shadow:0 10px 40px rgba(0,0,0,.5)}
#micro-panel[hidden]{display:none}
#micro-panel h3{font-size:13px;font-weight:700;letter-spacing:.4px;color:var(--accent);margin-bottom:16px}
.mstep{margin-bottom:16px;padding:2px 0 2px 13px;border-left:2px solid var(--edge)}
.mstep .lbl{font-size:12px;color:var(--dim);margin:2px 0}
.mstep .eq{font:17px/1.75 ui-monospace,Menlo,Consolas,monospace;color:var(--ink);
  font-variant-numeric:tabular-nums}
.mstep .eq.sm{font-size:14px;color:var(--dim)}
.mstep .eq .v{color:var(--accent);font-weight:700}
.mstep .eq .res{font-weight:700}
.mstep.measured{border-left-color:#cfe0f0}
.mstep.measured .res{color:#fff;font-size:21px}
.mstep.reads{border-left-color:#5fd07a}
.mstep.reads .res{color:#5fd07a;font-size:23px}
.mstep.implied{border-left-color:var(--app)}
.mstep.implied .res{color:var(--app);font-size:20px}
.mdefs{margin:16px 0 12px;padding:12px 14px;background:rgba(69,184,230,.06);
  border:1px solid var(--edge);border-radius:9px}
.mdefs .d{display:flex;gap:10px;padding:4px 0;font-size:12px;color:var(--dim);line-height:1.45}
.mdefs .d b{color:var(--accent);font-family:ui-monospace,Menlo,Consolas,monospace;
  min-width:18px;text-align:center;font-size:13px}
.mnull{font-size:12.5px;color:#5fd07a;text-align:center;
  background:rgba(95,208,122,.09);border:1px solid rgba(95,208,122,.3);border-radius:8px;padding:9px 10px}
.mnull b{color:#8fe6a5}

/* Brand (bottom-right, prominent) */
#brand{position:fixed;bottom:18px;right:20px;z-index:3;display:flex;flex-direction:column;
  align-items:center;gap:8px;pointer-events:none}
#brand a{pointer-events:auto;display:block;line-height:0}
#brand img{width:120px;height:120px;border-radius:50%;
  box-shadow:0 0 0 2px var(--edge),0 6px 26px rgba(0,0,0,.6);
  animation:acrgPulse 3.2s ease-in-out infinite}
@keyframes acrgPulse{
  0%,100%{transform:scale(1);     box-shadow:0 0 0 2px var(--edge),  0 6px 26px rgba(0,0,0,.6)}
  50%    {transform:scale(1.055); box-shadow:0 0 0 2px var(--accent),0 6px 34px rgba(69,184,230,.55)}}
@media (prefers-reduced-motion:reduce){#brand img{animation:none}}
#brand span{font-size:12px;font-weight:600;color:var(--dim);letter-spacing:.2px}

@media (max-width:860px){
  .panel{position:static;width:calc(100% - 32px);margin:16px}
  body{overflow:auto} #scene{position:fixed} #brand img{width:84px;height:84px}
}