:root {
  --bg: #070a12; --panel: rgba(14, 19, 32, .86); --line: #25304a; --text: #e8ecf5; --muted: #98a3bd;
  --accent: #6fd3ff; --bio: #ff6b6b; --sim: #b8c7ff; --yes: #5fe0b0; --no: #ff8a96; --maybe: #f0c75e;
  --a: #ff8a96; --b: #f0c75e; --c: #6fd3ff;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --sans: system-ui, -apple-system, "Segoe UI", sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; color-scheme: dark; }
body { margin: 0; background: var(--bg); color: var(--text); font: 17px/1.6 var(--sans); padding-bottom: 110px; }
#bg { position: fixed; inset: 0; width: 100%; height: 100%; z-index: 0; }
.vignette { position: fixed; inset: 0; z-index: 1; pointer-events: none;
  background: radial-gradient(ellipse at center, transparent 30%, var(--bg) 100%); opacity: .75; }
.top, main, footer, .gauge { position: relative; z-index: 2; }
.top { padding: 16px; }
.brand { font: 14px var(--mono); color: var(--accent); letter-spacing: .04em; }
.cursor { animation: blink 1.1s steps(1) infinite; }
@keyframes blink { 50% { opacity: 0; } }

main { max-width: 760px; margin: 0 auto; padding: 8px 16px 20px; outline: none; }
.step { animation: in .5s ease both; }
@keyframes in { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }
.tag { font: 12px var(--mono); letter-spacing: .08em; color: var(--accent); margin-bottom: 6px; }
h1 { font-size: clamp(30px, 6vw, 42px); line-height: 1.15; margin: 4px 0 14px; }
h2 { font-size: clamp(24px, 4.5vw, 31px); line-height: 1.25; margin: 4px 0 12px; }
h3 { font-size: 16px; margin: 26px 0 6px; }
p { margin: 0 0 14px; }
.muted { color: var(--muted); }
.ctx { color: #c5cde0; }

.visual { margin: 0 0 16px; min-height: 150px; display: flex; align-items: center; justify-content: center; }
.card { background: var(--panel); backdrop-filter: blur(6px); border: 1px solid var(--line); border-radius: 14px; padding: 24px 22px; }

/* aids and choices */
.aids { display: flex; gap: 8px; flex-wrap: wrap; margin: 4px 0 12px; }
.aid { background: none; border: 1px solid var(--line); color: var(--muted); border-radius: 999px; padding: 3px 12px; font: 12px var(--mono); cursor: pointer; }
.aid:hover, .aid.on { color: var(--accent); border-color: var(--accent); }
.aidp { border-left: 2px solid var(--accent); padding: 4px 0 4px 14px; margin: 0 0 14px; color: #c5cde0; font-size: 15.5px; }
.choices { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 18px 0; }
.choice { background: transparent; border: 1px solid var(--line); color: var(--text); border-radius: 10px; padding: 14px; font: 600 14px var(--mono); letter-spacing: .1em; text-transform: uppercase; cursor: pointer; transition: .15s; }
.choice:hover { transform: translateY(-1px); }
.choice.agree:hover, .choice.agree.sel { border-color: var(--yes); color: var(--yes); box-shadow: 0 0 18px -6px var(--yes); }
.choice.disagree:hover, .choice.disagree.sel { border-color: var(--no); color: var(--no); box-shadow: 0 0 18px -6px var(--no); }
.reflect { border: 1px solid var(--line); border-radius: 10px; padding: 14px 16px; margin: 0 0 16px; background: rgba(255,255,255,.02); }
.reflect p:last-child { margin-bottom: 0; }
.objs { display: grid; gap: 8px; margin: 8px 0 12px; }
.obj { text-align: left; background: transparent; border: 1px solid var(--line); color: var(--text); border-radius: 8px; padding: 9px 12px; font: 15px var(--sans); cursor: pointer; }
.obj:hover { border-color: var(--accent); }
.obj.sel { border-color: var(--accent); background: rgba(111, 211, 255, .08); }
.arg { margin-top: 8px; }
.commit { font: 13px var(--mono); color: var(--maybe); margin: 0; }
.row { display: flex; gap: 10px; flex-wrap: wrap; margin: 18px 0 4px; }
.btn { background: var(--accent); color: #04121c; border: 0; border-radius: 8px; padding: 10px 20px; font: 700 15px var(--sans); cursor: pointer; }
.btn.ghost { background: transparent; color: var(--text); border: 1px solid var(--line); font-weight: 500; }
.link { background: none; border: 0; color: var(--accent); cursor: pointer; font: inherit; text-decoration: underline; padding: 0; margin: 0 0 12px; text-align: left; }
footer .link { margin: 0 0 0 8px; font-size: 13px; }
button:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* progress  ● ━ ● ━ ○ */
.progress { display: flex; align-items: center; margin-top: 26px; }
.pd { background: none; border: 0; color: var(--muted); cursor: pointer; padding: 4px; display: flex; flex-direction: column; align-items: center; gap: 4px; }
.pd[disabled] { cursor: default; opacity: .45; }
.pd .dot { width: 14px; height: 14px; border-radius: 50%; border: 2px solid var(--line); background: transparent; }
.pd.agree .dot { background: var(--yes); border-color: var(--yes); }
.pd.disagree .dot { background: var(--no); border-color: var(--no); }
.pd.unsure .dot { background: var(--maybe); border-color: var(--maybe); }
.pd.current .dot { box-shadow: 0 0 0 4px rgba(111,211,255,.25); border-color: var(--accent); }
.pd .pl { font: 11px var(--mono); }
.bar { flex: 1; height: 2px; background: var(--line); min-width: 8px; margin-bottom: 18px; }

/* diagrams */
.dg { width: 100%; max-width: 640px; }
.dg text { font: 11px var(--mono); fill: var(--muted); text-anchor: middle; }
.brain path { fill: rgba(111,211,255,.08); stroke: var(--accent); stroke-width: 2; }
.brain .fold { fill: none; stroke-width: 1.5; opacity: .6; }
.flow { fill: none; stroke: var(--line); stroke-width: 2; stroke-dasharray: 4 5; }
.pulse { fill: var(--accent); filter: drop-shadow(0 0 4px var(--accent)); }
.model line { stroke: var(--accent); stroke-width: 1.2; opacity: .45; }
.model circle { fill: var(--accent); animation: glow 1.8s ease-in-out infinite; }
@keyframes glow { 50% { opacity: .3; } }
.sim-person circle:not(.aura), .sim-person path { fill: none; stroke: var(--sim); stroke-width: 2; stroke-dasharray: 3 3; }
.aura { fill: none; stroke: var(--sim); opacity: 0; }
.c-agree .sim-person circle:not(.aura), .c-agree .sim-person path { stroke-dasharray: none; fill: rgba(184,199,255,.15); filter: drop-shadow(0 0 8px var(--sim)); }
.c-agree .aura { opacity: .35; animation: ring 2.4s ease-out infinite; }
@keyframes ring { from { r: 30; opacity: .5; } to { r: 50; opacity: 0; } }
.c-disagree .sim-person { opacity: .3; }
.c-disagree .pulse.p2 { display: none; }
.c-unsure .sim-person { opacity: .65; }

.timeline { font-family: var(--mono); }
.tl-head { display: flex; justify-content: space-between; font-size: 11px; color: var(--muted); margin-bottom: 6px; }
.tl-track { position: relative; padding: 4px 0; background:
  linear-gradient(90deg, transparent 0, transparent 99%, var(--accent) 99%); border-bottom: 1px solid var(--line); }
.lane { position: relative; height: 12px; }
.trav { position: absolute; left: 0; top: 2px; width: 8px; height: 8px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 6px var(--accent);
  animation: travel var(--d) cubic-bezier(.4,0,.2,1) both; }
.trav.die { background: var(--no); box-shadow: none; animation: travel var(--d) cubic-bezier(.4,0,.2,1) both, fade .4s var(--d) forwards; }
.trav.ok { background: var(--yes); box-shadow: 0 0 8px var(--yes); }
@keyframes travel { to { left: var(--stop); } }
@keyframes fade { to { opacity: 0; } }
.x { position: absolute; top: -2px; font-size: 11px; color: var(--no); opacity: 0; animation: pop .3s forwards; transform: translateX(-3px); }
@keyframes pop { to { opacity: 1; } }
.tl-note { margin-top: 8px; font-size: 12px; color: var(--muted); text-align: center; }

.orig rect { fill: rgba(111,211,255,.1); stroke: var(--accent); }
.orig text { fill: var(--text); }
.branch { fill: none; stroke: var(--accent); stroke-width: 1.5; stroke-dasharray: 160; stroke-dashoffset: 160; animation: draw .8s ease forwards; }
.branch.ghost, .simw.ghost { opacity: .3; stroke-dasharray: 4 4; stroke-dashoffset: 0; animation: none; }
@keyframes draw { to { stroke-dashoffset: 0; } }
.simw { opacity: 0; animation: pop .4s forwards; }
.simw rect { fill: rgba(184,199,255,.12); stroke: var(--sim); }
.simw text { fill: var(--sim); }
.none, .dots { fill: var(--no); }

/* observer field */
.field { text-align: center; }
.field-dots { display: flex; flex-wrap: wrap; gap: 5px; justify-content: center; align-content: center; min-height: 100px; padding: 6px 4px; }
.d { display: inline-block; width: 9px; height: 9px; border-radius: 50%; }
.field-dots .d { opacity: 0; transform: scale(.3); animation: appear .4s ease forwards; }
@keyframes appear { to { opacity: 1; transform: none; } }
.d.sim { background: var(--sim); opacity: .7; }
.field-dots .d.sim { background: var(--sim); }
.d.bio { background: var(--bio); box-shadow: 0 0 10px var(--bio); width: 12px; height: 12px; }
.d.you { box-shadow: 0 0 0 3px var(--bg), 0 0 0 5px var(--accent), 0 0 14px var(--accent); background: #fff; width: 11px; height: 11px; opacity: 1; }
.legend { display: flex; flex-wrap: wrap; gap: 6px 18px; justify-content: center; font: 12px var(--mono); color: var(--muted); margin-top: 8px; }
.legend .d { vertical-align: middle; margin-right: 4px; animation: none; opacity: 1; transform: none; }
.legend .ratio { color: var(--accent); }
.field-note { font: 11px var(--mono); color: var(--muted); margin-top: 4px; min-height: 14px; }

/* result */
.trilemma { display: grid; gap: 10px; margin: 16px 0; }
.tcard { border: 1px solid var(--line); border-left-width: 5px; border-radius: 10px; padding: 12px 14px; opacity: .55; }
.tcard h3 { margin: 0 0 2px; color: inherit; }
.tcard.on { opacity: 1; }
.tcard.A { border-left-color: var(--a); } .tcard.A h3 { color: var(--a); }
.tcard.B { border-left-color: var(--b); } .tcard.B h3 { color: var(--b); }
.tcard.C { border-left-color: var(--c); } .tcard.C h3 { color: var(--c); }
.big { font: 700 42px var(--mono); color: var(--accent); }
.two { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.pane { border: 1px solid var(--line); border-radius: 10px; padding: 14px; font-size: 15px; }
.pane ul { padding-left: 18px; margin: 0 0 12px; }
@media (max-width: 620px) { .two { grid-template-columns: 1fr; } .pd .pl { display: none; } }
table { width: 100%; border-collapse: collapse; font: 14px var(--mono); margin: 10px 0 20px; }
th, td { text-align: left; padding: 7px 6px; border-bottom: 1px solid var(--line); }
th { color: var(--muted); font-weight: 500; }
td.now { color: var(--accent); font-weight: 700; }
.sliders label { display: block; font-size: 14px; margin: 14px 0 2px; }
.sliders input { width: 100%; accent-color: var(--accent); }

.gauge { position: fixed; left: 0; right: 0; bottom: 0; z-index: 6; background: rgba(7,10,18,.92); border-top: 1px solid var(--line); padding: 10px 16px; }
.gauge-in { max-width: 760px; margin: 0 auto; font: 13px var(--mono); color: var(--muted); }
.gauge-in strong { color: var(--text); }
.meter { height: 8px; background: var(--line); border-radius: 6px; overflow: hidden; margin-top: 6px; }
.meter i { display: block; height: 100%; background: var(--accent); transition: width .5s ease; }
footer { max-width: 760px; margin: 36px auto 0; padding: 0 16px; color: var(--muted); font-size: 13px; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .001s !important; animation-delay: 0s !important; transition: none !important; }
  html { scroll-behavior: auto; }
}