:root {
  --green-dark: #2f5d33;
  --green: #4c8a50;
  --green-light: #eaf4e6;
  --ink: #2c352a;
  --paper: #fffdf5;
  --accent: #ef8f2c;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Hiragino Maru Gothic ProN", "Hiragino Sans", "Noto Sans JP", sans-serif;
  background: var(--green-light);
  color: var(--ink);
  line-height: 1.6;
}

.site-header {
  background: var(--green-dark);
  color: #fff;
  text-align: center;
  padding: 18px 12px 14px;
}
.site-header h1 { margin: 0; font-size: 1.55rem; letter-spacing: 0.04em; }
.header-sub { margin: 4px 0 0; font-size: 0.88rem; opacity: 0.9; }
.intro { max-width: 640px; margin: 12px auto; padding: 0 12px; font-size: 0.92rem; line-height: 1.7; }

main {
  max-width: 480px;
  margin: 0 auto;
  padding: 10px 12px 20px;
}

.ad-box {
  border: 2px dashed #b9c8b4;
  background: #f4f8f1;
  color: #8ba184;
  text-align: center;
  padding: 26px 0;
  margin: 10px 0;
  font-size: 0.85rem;
  border-radius: 8px;
}

.hud {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--paper);
  border: 2px solid var(--green);
  border-radius: 12px;
  padding: 8px 14px;
  gap: 8px;
}
.hud-item { display: flex; flex-direction: column; align-items: center; min-width: 64px; }
.hud-label { font-size: 0.72rem; color: var(--green-dark); font-weight: bold; }
.hud-value { font-size: 1.3rem; font-weight: bold; line-height: 1.2; }
.hud-next { min-width: 64px; }
#nextCanvas { width: 48px; height: 48px; }

.controls {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin: 10px 0;
  flex-wrap: wrap;
}
.btn {
  font: inherit;
  font-size: 0.9rem;
  border: 2px solid var(--green-dark);
  background: #fff;
  color: var(--green-dark);
  border-radius: 999px;
  padding: 6px 16px;
  cursor: pointer;
}
.btn:active { transform: translateY(1px); }
.btn-main {
  background: var(--accent);
  border-color: #c96f14;
  color: #fff;
  font-weight: bold;
  padding: 10px 26px;
}
.btn-toggle[aria-pressed="false"] { opacity: 0.55; }

.game-frame {
  position: relative;
  background: #fdf6e3;
  border: 3px solid #8a6d4b;
  border-radius: 10px;
  overflow: hidden;
}
#gameCanvasWrap { line-height: 0; }
#gameCanvasWrap canvas {
  width: 100%;
  height: auto;
  display: block;
  touch-action: none;
}

.gameover-overlay {
  position: absolute;
  inset: 0;
  background: rgba(30, 40, 28, 0.82);
  color: #fff;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 16px;
  z-index: 5;
}
.gameover-overlay[hidden] { display: none; }
.gameover-title { font-size: 1.6rem; font-weight: bold; margin: 0 0 8px; }
.gameover-score { font-size: 1.15rem; margin: 0 0 2px; }
.gameover-best { margin: 0 0 14px; font-size: 0.9rem; color: #ffd9a0; min-height: 1.2em; }
.gameover-link { margin-top: 14px; font-size: 0.85rem; }
.gameover-link a { color: #ffe9c4; }

.play-hint { font-size: 0.8rem; color: #5c6b58; text-align: center; margin: 8px 0 0; }

.howto, .chart {
  background: var(--paper);
  border-radius: 12px;
  padding: 14px 18px;
  margin-top: 16px;
}
.howto h2, .chart h2 { margin: 0 0 8px; font-size: 1.1rem; color: var(--green-dark); }
.howto ul { margin: 0; padding-left: 1.2em; font-size: 0.92rem; }
.chart p { margin: 0 0 8px; font-size: 0.92rem; }
.chart-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px 14px;
  font-size: 0.92rem;
}
.chart-dot {
  display: inline-block;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  border: 1px solid rgba(0,0,0,0.25);
  vertical-align: -3px;
  margin-right: 6px;
}

.site-footer {
  background: var(--green-dark);
  color: #eaf4e6;
  text-align: center;
  padding: 18px 12px 26px;
  margin-top: 10px;
}
.sister-title { font-weight: bold; margin: 0 0 6px; }
.sister-links ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px 16px;
}
.sister-links a { color: #ffe9c4; font-size: 0.9rem; }
.footer-note { font-size: 0.78rem; opacity: 0.85; margin: 12px 0 0; }