:root {
  --navy: #0b2545;
  --navy-2: #13315c;
  --ink: #f6f1e3;
  --muted: #c3cbe0;
  --gold: #e8b84a;
  --gold-light: #fff1b8;
  --gold-deep: #9a6b12;
  --panel: rgb(255 255 255 / 0.07);
  --panel-border: rgb(232 184 74 / 0.35);
  --error-bg: #5c1a1a;
  --error-ink: #ffd6d6;
  --serif: "Georgia", "Times New Roman", serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { background: var(--navy); }
body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  font: 17px/1.5 var(--sans);
  background:
    radial-gradient(ellipse at 50% -10%, #1f4a85 0%, transparent 60%),
    url("/pattern.svg") center / 180px repeat,
    linear-gradient(180deg, var(--navy-2), var(--navy));
  background-attachment: fixed;
  overflow-x: hidden;
}
.vault {
  max-width: 520px;
  margin: 0 auto;
  padding: 32px 16px 48px;
  text-align: center;
}
.eyebrow {
  margin: 0;
  font-size: 0.8rem;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--gold);
  font-weight: 700;
}
h1 {
  margin: 4px 0 8px;
  font-family: var(--serif);
  font-size: clamp(2rem, 7vw, 2.8rem);
  line-height: 1.1;
  color: var(--gold-light);
  text-shadow: 0 2px 0 var(--gold-deep), 0 6px 18px rgb(0 0 0 / 0.4);
}
.lead { margin: 0 auto 8px; max-width: 30em; color: var(--muted); }

/* ---------- The coin ---------- */
.stage { perspective: 900px; padding: 20px 0 4px; }
.coin {
  position: relative;
  width: min(62vw, 240px);
  aspect-ratio: 1;
  margin: 0 auto;
  padding: 0;
  border: 0;
  background: none;
  cursor: pointer;
  transform-style: preserve-3d;
  transition: transform 1.2s cubic-bezier(.2, .8, .2, 1);
  animation: float 3.5s ease-in-out infinite;
  -webkit-tap-highlight-color: transparent;
}
.coin:focus-visible { outline: 3px dashed var(--gold); outline-offset: 10px; border-radius: 50%; }
.coin .face {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  filter: drop-shadow(0 10px 18px rgb(0 0 0 / 0.45));
}
.coin .face svg { width: 100%; height: 100%; display: block; }
.coin .reverse { transform: rotateY(180deg); }
.coin.flipped { transform: rotateY(180deg); }
.coin.spin { animation: spin 0.9s cubic-bezier(.3, .7, .3, 1); }
.coin.flipped.spin { animation: spin-flipped 0.9s cubic-bezier(.3, .7, .3, 1); }
.coin.searching { animation: searching 0.6s linear infinite; }
.coin.shake { animation: shake 0.5s ease; }

.rim-text {
  font: 700 13px var(--serif);
  letter-spacing: 2px;
  fill: #6b4a08;
}
.big-yn {
  font: 700 58px var(--serif);
  fill: #7a5409;
  stroke: #fff1b8;
  stroke-width: 1;
  paint-order: stroke;
}
.reverse-text {
  position: absolute;
  inset: 0;
  display: grid;
  place-content: center;
  color: #5e3f05;
  text-shadow: 0 1px 0 rgb(255 241 184 / 0.8);
}
.reverse-text .value {
  font: 700 clamp(2rem, 13vw, 3.4rem) / 1 var(--serif);
  font-variant-numeric: tabular-nums;
}
.reverse-text .value.long { font-size: clamp(1.5rem, 9vw, 2.4rem); }
.reverse-text .denom {
  margin-top: 4px;
  font: 700 0.8rem var(--serif);
  letter-spacing: 0.2em;
  text-transform: uppercase;
}
.coin-shadow {
  width: min(40vw, 150px);
  height: 14px;
  margin: 14px auto 0;
  border-radius: 50%;
  background: rgb(0 0 0 / 0.35);
  filter: blur(6px);
  animation: shadow 3.5s ease-in-out infinite;
}

@keyframes float { 50% { translate: 0 -10px; } }
@keyframes shadow { 50% { scale: 0.8; opacity: 0.6; } }
@keyframes spin { from { transform: rotateY(0); } to { transform: rotateY(720deg); } }
@keyframes spin-flipped { from { transform: rotateY(180deg); } to { transform: rotateY(900deg); } }
@keyframes searching { to { transform: rotateY(360deg); } }
@keyframes shake {
  20%, 60% { translate: -10px 0; }
  40%, 80% { translate: 10px 0; }
}

/* ---------- Coin slot form ---------- */
.slot {
  margin: 24px auto 0;
  padding: 18px;
  text-align: left;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 18px;
}
.slot label {
  display: block;
  margin-bottom: 8px;
  font-weight: 700;
  color: var(--gold-light);
}
.slot-row { display: flex; gap: 10px; }
.slot input {
  flex: 1;
  min-width: 0;
  font: 700 1.4rem var(--sans);
  letter-spacing: 0.08em;
  padding: 12px 14px;
  border: 2px solid transparent;
  border-radius: 12px;
  background: #06172d;
  color: var(--ink);
  box-shadow: inset 0 3px 8px rgb(0 0 0 / 0.6);
}
.slot input::placeholder { color: #5f6f8f; font-weight: 400; letter-spacing: 0; }
.slot input:focus { outline: none; border-color: var(--gold); }

button#go, .ghost {
  font: 700 1.05rem var(--sans);
  border-radius: 12px;
  cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}
button#go {
  padding: 12px 20px;
  border: 0;
  color: #3b2605;
  background: linear-gradient(180deg, var(--gold-light), var(--gold) 55%, #c8911f);
  box-shadow: 0 4px 0 var(--gold-deep), 0 8px 16px rgb(0 0 0 / 0.3);
}
button#go:hover { transform: translateY(-2px); }
button#go:active { transform: translateY(3px); box-shadow: 0 1px 0 var(--gold-deep); }
button#go:disabled { opacity: 0.7; cursor: wait; transform: none; }
.ghost {
  padding: 10px 16px;
  border: 1px solid var(--panel-border);
  background: transparent;
  color: var(--gold-light);
}
.ghost:hover { background: rgb(232 184 74 / 0.12); }
.ghost.small { font-size: 0.9rem; padding: 6px 12px; }

.error {
  margin: 16px 0 0;
  padding: 12px 14px;
  border-radius: 12px;
  background: var(--error-bg);
  color: var(--error-ink);
}

/* ---------- Result ---------- */
.result {
  margin-top: 20px;
  padding: 20px;
  border-radius: 18px;
  background: linear-gradient(180deg, rgb(232 184 74 / 0.18), rgb(232 184 74 / 0.05));
  border: 1px solid var(--panel-border);
  animation: pop 0.5s cubic-bezier(.2, 1.4, .4, 1);
}
.result-line { margin: 0; color: var(--muted); }
.result-total {
  margin: 2px 0 6px;
  font: 700 clamp(1.8rem, 8vw, 2.4rem) / 1.15 var(--serif);
  color: var(--gold-light);
}
.rank {
  display: inline-block;
  margin: 0 0 14px;
  padding: 6px 14px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.95rem;
  color: #1a1204;
  background: var(--rank-color, var(--gold));
}
@keyframes pop { from { opacity: 0; scale: 0.9; } }

/* ---------- Fun fact ---------- */
.fact {
  margin-top: 28px;
  padding: 16px 18px;
  text-align: left;
  border-radius: 16px;
  background: var(--panel);
  border-left: 4px solid var(--gold);
}
.fact-title {
  margin: 0 0 6px;
  font-weight: 700;
  color: var(--gold);
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
#fact-text { margin: 0 0 10px; min-height: 3em; }
.help { margin: 24px 0 0; font-size: 0.9rem; color: var(--muted); }

/* ---------- Falling coins ---------- */
.coin-rain { position: fixed; inset: 0; pointer-events: none; overflow: hidden; z-index: 10; }
.coin-rain span {
  position: absolute;
  top: -60px;
  width: var(--size, 28px);
  aspect-ratio: 1;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 30%, var(--gold-light), var(--gold) 55%, var(--gold-deep));
  box-shadow: inset 0 0 0 2px rgb(154 107 18 / 0.7);
  animation: fall var(--dur, 2.4s) cubic-bezier(.4, 0, .8, .6) var(--delay, 0s) forwards;
}
.coin-rain span.silver { background: radial-gradient(circle at 35% 30%, #ffffff, #c9ced6 55%, #7d8591); box-shadow: inset 0 0 0 2px rgb(90 97 108 / 0.7); }
.coin-rain span.copper { background: radial-gradient(circle at 35% 30%, #ffd3b0, #c8733a 55%, #7a3d14); box-shadow: inset 0 0 0 2px rgb(110 50 15 / 0.7); }
@keyframes fall {
  to { transform: translate(var(--drift, 0), 110vh) rotateX(var(--flips, 720deg)) rotate(var(--turn, 200deg)); }
}

@media (max-width: 380px) {
  .slot-row { flex-direction: column; }
}
@media (prefers-reduced-motion: reduce) {
  .coin, .coin-shadow { animation: none !important; transition: none; }
  .coin.searching { animation: none !important; opacity: 0.7; }
  .coin-rain { display: none; }
  .result { animation: none; }
}