:root {
  --bg: #0b1220;
  --bg-elev: #121a2b;
  --line: rgba(255, 255, 255, 0.1);
  --text: #eef3ff;
  --muted: #9aa8c3;
  --accent: #5eead4;
  --accent-2: #38bdf8;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  --glass: rgba(255, 255, 255, 0.22);
  --radius: 22px;
  --bottle-w: 62px;
  --bottle-h: 220px;
  --layer-h: 44px;
}

* {
  box-sizing: border-box;
}

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

body {
  font-family: "Hiragino Sans", "Yu Gothic", "Noto Sans JP", system-ui, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

.bg-glow {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse at 20% 0%, rgba(56, 189, 248, 0.16), transparent 42%),
    radial-gradient(ellipse at 90% 10%, rgba(94, 234, 212, 0.12), transparent 38%),
    radial-gradient(ellipse at 50% 100%, rgba(167, 139, 250, 0.1), transparent 40%);
  z-index: 0;
}

.site-header,
main,
.site-footer {
  position: relative;
  z-index: 1;
  width: min(920px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  padding: 36px 0 12px;
  text-align: center;
}

.eyebrow {
  margin: 0 0 8px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 0.72rem;
  color: var(--accent);
}

h1 {
  margin: 0;
  font-size: clamp(1.7rem, 4vw, 2.4rem);
  letter-spacing: 0.02em;
}

.lede {
  margin: 12px auto 0;
  max-width: 38rem;
  color: var(--muted);
}

.panel {
  margin-top: 22px;
  padding: 20px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.05), rgba(255, 255, 255, 0.02));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.hud {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.stat {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.stat-label {
  color: var(--muted);
  font-size: 0.9rem;
}

.stat-value {
  font-variant-numeric: tabular-nums;
  font-size: 1.5rem;
  font-weight: 700;
}

.actions,
.modal-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.btn {
  appearance: none;
  border: 0;
  border-radius: 999px;
  padding: 0.7rem 1.15rem;
  font: inherit;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, box-shadow 0.15s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

.btn-primary {
  color: #042f2e;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  font-weight: 700;
}

.btn-ghost {
  color: var(--text);
  background: transparent;
  border: 1px solid var(--line);
}

.board {
  display: grid;
  grid-template-columns: repeat(6, var(--bottle-w));
  justify-content: center;
  gap: 22px 28px;
  margin: 28px 0 8px;
  min-height: calc(var(--bottle-h) + 36px);
}

.bottle {
  position: relative;
  width: var(--bottle-w);
  height: var(--bottle-h);
  padding: 10px 8px 12px;
  border: 0;
  background: transparent;
  cursor: pointer;
  display: flex;
  flex-direction: column-reverse;
  align-items: stretch;
  gap: 0;
  filter: drop-shadow(0 10px 12px rgba(0, 0, 0, 0.28));
}

.bottle::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 12px 12px 28px 28px;
  border: 3px solid var(--glass);
  border-top-color: rgba(255, 255, 255, 0.4);
  background: linear-gradient(90deg, rgba(255, 255, 255, 0.07), transparent 28%, transparent 72%, rgba(255, 255, 255, 0.08));
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.08);
  pointer-events: none;
}

.bottle::after {
  content: "";
  position: absolute;
  top: -10px;
  left: 12px;
  right: 12px;
  height: 16px;
  border: 3px solid rgba(255, 255, 255, 0.38);
  border-bottom: 0;
  border-radius: 8px 8px 0 0;
  background: rgba(18, 26, 43, 0.45);
  pointer-events: none;
}

.bottle.selected {
  transform: translateY(-12px);
}

.bottle.selected::before {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(94, 234, 212, 0.18);
}

.bottle.complete::before {
  border-color: rgba(74, 222, 128, 0.7);
}

.layer {
  height: var(--layer-h);
  margin: 0 6px;
  background: var(--c);
  box-shadow: inset 0 8px 10px rgba(255, 255, 255, 0.18), inset 0 -6px 10px rgba(0, 0, 0, 0.18);
}

.layer:first-child {
  border-radius: 0 0 20px 20px;
}

.layer + .layer {
  margin-top: 0;
}

.status {
  text-align: center;
  color: var(--muted);
  min-height: 1.6em;
  margin: 8px 0 0;
}

.howto {
  margin: 28px 0 12px;
  padding: 8px 4px 24px;
}

.howto h2 {
  margin: 0 0 10px;
  font-size: 1.1rem;
}

.howto ol {
  margin: 0;
  padding-left: 1.2rem;
  color: var(--muted);
}

.site-footer {
  padding: 8px 0 32px;
  color: var(--muted);
  font-size: 0.85rem;
  text-align: center;
}

.modal {
  position: fixed;
  inset: 0;
  z-index: 20;
  display: grid;
  place-items: center;
  background: rgba(5, 8, 16, 0.62);
  padding: 20px;
}

.modal[hidden] {
  display: none;
}

.modal-card {
  width: min(420px, 100%);
  padding: 28px 24px;
  border-radius: 24px;
  background: var(--bg-elev);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  text-align: center;
}

.modal-kicker {
  margin: 0;
  color: var(--accent);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 0.75rem;
}

.modal-card h2 {
  margin: 8px 0 6px;
  font-size: 2rem;
}

.modal-card p {
  color: var(--muted);
}

.modal-actions {
  justify-content: center;
  margin-top: 18px;
}

@media (max-width: 720px) {
  :root {
    --bottle-w: 52px;
    --bottle-h: 196px;
    --layer-h: 38px;
  }

  .board {
    grid-template-columns: repeat(3, var(--bottle-w));
    gap: 28px 36px;
  }

  .panel {
    padding: 16px 14px 18px;
  }

  .actions {
    width: 100%;
  }

  .btn {
    flex: 1;
  }
}

@media (max-width: 380px) {
  :root {
    --bottle-w: 46px;
    --bottle-h: 180px;
    --layer-h: 34px;
  }

  .board {
    gap: 22px 18px;
  }
}