:root {
  --bg: #0b0d1f;
  --bg2: #151936;
  --card: rgba(255, 255, 255, 0.05);
  --line: rgba(255, 255, 255, 0.09);
  --text: #eef0ff;
  --dim: #8e93c2;
  --moon: #ffd98a;
  --moon-2: #ffb86b;
  --accent: #8b7dff;
  --radius: 20px;
}

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

html, body { margin: 0; min-height: 100%; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Rounded", "Segoe UI", system-ui, sans-serif;
  color: var(--text);
  background: radial-gradient(120% 80% at 80% -10%, #2a2466 0%, transparent 60%),
              radial-gradient(90% 60% at 0% 110%, #1b2a55 0%, transparent 60%),
              linear-gradient(180deg, var(--bg2), var(--bg));
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
}

.stars {
  position: fixed; inset: 0; pointer-events: none; opacity: .55;
  background-image:
    radial-gradient(1px 1px at 12% 18%, #fff 50%, transparent 51%),
    radial-gradient(1px 1px at 72% 12%, #fff 50%, transparent 51%),
    radial-gradient(1.5px 1.5px at 40% 30%, #cfd3ff 50%, transparent 51%),
    radial-gradient(1px 1px at 88% 44%, #fff 50%, transparent 51%),
    radial-gradient(1px 1px at 22% 62%, #fff 50%, transparent 51%),
    radial-gradient(1.5px 1.5px at 60% 78%, #cfd3ff 50%, transparent 51%),
    radial-gradient(1px 1px at 8% 88%, #fff 50%, transparent 51%),
    radial-gradient(1px 1px at 94% 92%, #fff 50%, transparent 51%);
  animation: twinkle 6s ease-in-out infinite alternate;
}
@keyframes twinkle { from { opacity: .35; } to { opacity: .7; } }

.app {
  position: relative;
  max-width: 440px;
  margin: 0 auto;
  padding: calc(18px + env(safe-area-inset-top)) 18px calc(28px + env(safe-area-inset-bottom));
  display: flex; flex-direction: column; gap: 12px;
}

.top { display: flex; justify-content: space-between; align-items: center; padding: 4px 4px 6px; }
.brand { font-weight: 700; font-size: 18px; letter-spacing: -0.01em; }
.moon { display: inline-block; filter: drop-shadow(0 0 10px rgba(255, 217, 138, .6)); animation: bob 4s ease-in-out infinite; }
@keyframes bob { 50% { transform: translateY(-2px) rotate(-6deg); } }
.clock {
  font-variant-numeric: tabular-nums; font-size: 13px; color: var(--dim);
  padding: 6px 10px; border: 1px solid var(--line); border-radius: 999px;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.label { font-size: 12px; text-transform: uppercase; letter-spacing: .09em; color: var(--dim); font-weight: 600; }
.sub { font-size: 13px; color: var(--dim); margin-top: 4px; opacity: .8; }

.bill-row { display: flex; align-items: baseline; gap: 6px; margin-top: 6px; }
.currency { font-size: 34px; color: var(--dim); font-weight: 600; }
#bill {
  flex: 1; min-width: 0; background: none; border: 0; outline: 0;
  color: var(--text); font: inherit; font-size: 48px; font-weight: 700; letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums; caret-color: var(--moon);
}
#bill::placeholder { color: rgba(255, 255, 255, .18); }
.bill-card:focus-within { border-color: rgba(255, 217, 138, .45); box-shadow: 0 0 0 4px rgba(255, 217, 138, .08); }

.vibes { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin-top: 12px; }
.vibe {
  display: flex; flex-direction: column; align-items: center; gap: 2px;
  padding: 10px 4px; border-radius: 14px; border: 1px solid var(--line);
  background: rgba(255, 255, 255, .03); color: var(--text); font: inherit; cursor: pointer;
  transition: transform .15s ease, background .2s ease, border-color .2s ease;
}
.vibe:active { transform: scale(.95); }
.vibe .e { font-size: 22px; }
.vibe .p { font-weight: 700; font-size: 15px; font-variant-numeric: tabular-nums; }
.vibe .t { font-size: 10.5px; color: var(--dim); white-space: nowrap; }
.vibe.on {
  background: linear-gradient(160deg, rgba(255, 217, 138, .22), rgba(139, 125, 255, .18));
  border-color: rgba(255, 217, 138, .55);
}
.vibe.on .t { color: var(--moon); }

.slider-row { display: flex; align-items: center; gap: 12px; margin-top: 14px; }
#pct { flex: 1; -webkit-appearance: none; appearance: none; height: 6px; border-radius: 99px; background: rgba(255,255,255,.1); outline: none; }
#pct::-webkit-slider-thumb {
  -webkit-appearance: none; width: 24px; height: 24px; border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, #fff3cf, var(--moon) 55%, var(--moon-2));
  box-shadow: 0 0 14px rgba(255, 217, 138, .6); cursor: pointer; border: 0;
}
#pct::-moz-range-thumb {
  width: 24px; height: 24px; border-radius: 50%; border: 0;
  background: radial-gradient(circle at 35% 35%, #fff3cf, var(--moon) 55%, var(--moon-2));
  box-shadow: 0 0 14px rgba(255, 217, 138, .6);
}
#pctOut { min-width: 46px; text-align: right; font-weight: 700; font-variant-numeric: tabular-nums; color: var(--moon); }

.verdict { margin: 12px 0 0; font-size: 14px; color: var(--text); opacity: .85; min-height: 1.3em; transition: opacity .2s; }
.verdict.swap { opacity: 0; }

.split-card, .toggle-card { display: flex; justify-content: space-between; align-items: center; gap: 12px; }

.stepper { display: flex; align-items: center; gap: 4px; background: rgba(255,255,255,.05); border: 1px solid var(--line); border-radius: 999px; padding: 4px; }
.stepper button {
  width: 38px; height: 38px; border-radius: 50%; border: 0; cursor: pointer;
  background: rgba(255,255,255,.08); color: var(--text); font-size: 20px; line-height: 1;
  transition: transform .12s ease, background .2s;
}
.stepper button:active { transform: scale(.88); background: rgba(255,255,255,.16); }
.stepper button:disabled { opacity: .3; }
#people { min-width: 30px; text-align: center; font-weight: 700; font-size: 18px; font-variant-numeric: tabular-nums; }

.switch {
  width: 52px; height: 32px; border-radius: 999px; border: 0; padding: 3px; cursor: pointer;
  background: rgba(255,255,255,.12); transition: background .25s ease; flex-shrink: 0;
}
.switch span { display: block; width: 26px; height: 26px; border-radius: 50%; background: #fff; transition: transform .25s cubic-bezier(.3,1.4,.5,1); }
.switch[aria-checked="true"] { background: linear-gradient(90deg, var(--moon-2), var(--moon)); }
.switch[aria-checked="true"] span { transform: translateX(20px); }

.result {
  margin-top: 4px;
  border-radius: 24px;
  padding: 20px;
  background: linear-gradient(155deg, #fff1c9 0%, var(--moon) 45%, var(--moon-2) 100%);
  color: #1d1633;
  box-shadow: 0 18px 50px -18px rgba(255, 184, 107, .55);
}
.result .label { color: rgba(29, 22, 51, .6); }
.amount { font-size: 56px; font-weight: 800; letter-spacing: -0.04em; font-variant-numeric: tabular-nums; line-height: 1.05; margin-top: 4px; }
.amount.pop { animation: pop .28s ease; }
@keyframes pop { 40% { transform: scale(1.04); } }
.rows { margin-top: 14px; border-top: 1px solid rgba(29, 22, 51, .15); padding-top: 10px; display: grid; gap: 6px; }
.row { display: flex; justify-content: space-between; font-size: 15px; font-variant-numeric: tabular-nums; }
.row span:first-child { color: rgba(29, 22, 51, .65); }
.row span:last-child { font-weight: 700; }

.reset {
  margin-top: 4px; align-self: center; background: none; border: 1px solid var(--line); color: var(--dim);
  font: inherit; font-size: 14px; padding: 10px 20px; border-radius: 999px; cursor: pointer;
}
.reset:active { background: rgba(255,255,255,.06); }
.foot { text-align: center; font-size: 12px; color: var(--dim); opacity: .6; padding-top: 4px; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
}