:root {
  --bg: #0f1115; --card: #1a1d24; --fg: #eef1f6; --muted: #9aa3b2;
  --accent: #4f8cff; --line: #2a2f3a;
  --green: #2ec27e; --amber: #f5a623; --red: #ef4d4d;
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--bg); color: var(--fg);
  font: 16px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  padding: max(16px, env(safe-area-inset-top)) 16px 32px;
}
main { max-width: 560px; margin: 0 auto; }
h1 { font-size: clamp(1.4rem, 6vw, 2rem); margin: .3em 0 .2em; }
.sub { color: var(--muted); margin: 0 0 1.4em; }

form { display: flex; flex-wrap: wrap; gap: 10px; }
#reg {
  flex: 1 1 180px; min-width: 0; font-size: 1.25rem; letter-spacing: .12em;
  text-transform: uppercase; text-align: center; font-weight: 700;
  padding: 12px 14px; min-height: 48px; border-radius: 10px;
  border: 2px solid var(--line); background: #fbe94a; color: #111;
}
#reg::placeholder { color: #7a7330; font-weight: 600; letter-spacing: .06em; }
#go {
  flex: 0 0 auto; min-height: 48px; padding: 0 22px; font-size: 1.05rem; font-weight: 700;
  border: 0; border-radius: 10px; background: var(--accent); color: #fff; cursor: pointer;
}
#go:disabled { opacity: .5; cursor: progress; }

.status { min-height: 1.4em; color: var(--muted); margin: 14px 2px; }
.status.error { color: var(--red); }

#result { margin-top: 8px; }
#gauge { width: 100%; }
#gauge svg { display: block; width: 100%; height: auto; }

.verdict { text-align: center; font-size: 1.05rem; margin: 4px 0 18px; color: var(--muted); }
.verdict b { font-size: 1.15rem; }

.facts {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 10px; margin: 0; padding: 0;
}
.facts div { background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 10px 12px; }
.facts dt { color: var(--muted); font-size: .78rem; text-transform: uppercase; letter-spacing: .04em; }
.facts dd { margin: 2px 0 0; font-size: 1.05rem; font-weight: 600; }

#explain {
  margin-top: 18px; background: var(--card); border: 1px solid var(--line);
  border-radius: 10px; padding: 14px 12px 6px;
}
#explain h2 {
  color: var(--muted); font-size: .78rem; font-weight: 600;
  text-transform: uppercase; letter-spacing: .04em; margin: 0 0 10px;
}
#waterfall svg { display: block; width: 100%; height: auto; }
#explain .note { color: var(--muted); font-size: .78rem; margin: 6px 0 8px; }

.disclaimer { color: var(--muted); font-size: .82rem; margin: 18px 2px 0; }
footer { margin-top: 28px; padding-top: 14px; border-top: 1px solid var(--line); }
footer p { color: var(--muted); font-size: .8rem; }
footer a, .disclaimer a { color: var(--accent); }

.visually-hidden {
  position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0);
}
@media (prefers-reduced-motion: no-preference) {
  #gauge svg .needle, #gauge svg .arc-fill { transition: all .6s cubic-bezier(.2,.7,.2,1); }
}