.prefecture-map {
  box-sizing: border-box;
  display: grid;
  grid-template-columns: repeat(29, minmax(0, 1fr));
  grid-template-rows: repeat(28, minmax(0, 1fr));
  gap: 2px;
  width: min(575px, 100%);
  aspect-ratio: 575 / 440;
  margin: 0 auto;
  padding: 0;
}

.prefecture-map__pref {
  box-sizing: border-box;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0.15rem;
  border: none;
  border-radius: 5px;
  appearance: none;
  -webkit-appearance: none;
  font-family: inherit;
  font-size: clamp(0.55rem, 1.7vw, 0.72rem);
  font-weight: 700;
  line-height: 1.2;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, filter 0.15s ease;
}

.prefecture-map__pref:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgb(0 0 0 / 18%);
  filter: brightness(1.05);
}

.prefecture-map__pref:focus {
  outline: none;
}

.prefecture-map__pref--light-text {
  color: #fff;
}

.prefecture-map__pref--dark-text {
  color: #111827;
}

/* 地域カラー */
.prefecture-map__pref--hokkaido      { background: #64b9df; }
.prefecture-map__pref--tohoku        { background: #2b9bcc; }
.prefecture-map__pref--kanto         { background: #48a852; }
.prefecture-map__pref--niigata       { background: #6dc076; }
.prefecture-map__pref--nagano        { background: #edecea; }
.prefecture-map__pref--yamanashi     { background: #16a34a; }
.prefecture-map__pref--shizuoka,
.prefecture-map__pref--gifu,
.prefecture-map__pref--aichi,
.prefecture-map__pref--mie           { background: #0d9488; }
.prefecture-map__pref--hokuriku      { background: #c480c6; }
.prefecture-map__pref--kansai-yellow { background: #f0a32f; }
.prefecture-map__pref--kansai-grey   { background: #edecea; }
.prefecture-map__pref--chugoku       { background: #ec5551; }
.prefecture-map__pref--chugoku-grey  { background: #edecea; }
.prefecture-map__pref--kyushu        { background: #ec5551; }
.prefecture-map__pref--kyushu-grey   { background: #edecea; }
.prefecture-map__pref--okinawa       { background: #ec5551; }

@media (max-width: 640px) {
  .prefecture-map {
    gap: 2px;
  }

  .prefecture-map__pref {
    border-radius: 4px;
    font-size: clamp(0.48rem, 2.4vw, 0.65rem);
  }
}

@media (prefers-reduced-motion: reduce) {
  .prefecture-map__pref {
    transition: none;
  }
}