body {
  margin: 0;
  font-family: 'BIZ UDPGothic', 'Segoe UI', 'Meiryo', sans-serif;
  background: #f7f7f7;
  color: #222;
}
header {
  width: 100%;
  background: #fff;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 16px 0 8px 0;
}
header img {
  max-width: 320px;
  width: 80vw;
  height: auto;
  display: block;
}
.contents-section {
  max-width: 1200px;
  margin: 40px auto 0 auto;
  padding: 24px 32px;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  text-align: center;
}
.contents-section h2 {
  font-size: 2.2em;
  margin-bottom: 20px;
  text-align: center;
}
.tiles {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  justify-content: center;
  margin-top: 24px;
  padding-left: 16px;
  padding-right: 16px;
}
@media (min-width: 600px) {
  .tiles {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    padding-left: 24px;
    padding-right: 24px;
  }
}
@media (min-width: 800px) {
  .tiles {
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    padding-left: 32px;
    padding-right: 32px;
  }
}
.tile {
  position: relative;
  aspect-ratio: 1/1;
  background: #e0e0e0;
  border-radius: 10px;
  overflow: hidden;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
  transition: transform 0.15s, box-shadow 0.15s;
}
.tile.cleared {
  box-shadow: 0 0 0 3px #4caf50, 0 2px 8px rgba(0,0,0,0.06);
  animation: glow-green 2s ease-in-out infinite alternate;
}
.tile.extra-cleared {
  box-shadow: 0 0 0 3px #00bcd4, 0 2px 8px rgba(0,0,0,0.06);
  animation: glow-cyan 2s ease-in-out infinite alternate;
}
@keyframes glow-green {
  from {
    box-shadow: 0 0 0 3px #4caf50, 0 2px 8px rgba(0,0,0,0.06);
  }
  to {
    box-shadow: 0 0 0 3px #4caf50, 0 0 20px rgba(76, 175, 80, 0.6), 0 2px 8px rgba(0,0,0,0.06);
  }
}
@keyframes glow-cyan {
  from {
    box-shadow: 0 0 0 3px #00bcd4, 0 2px 8px rgba(0,0,0,0.06);
  }
  to {
    box-shadow: 0 0 0 3px #00bcd4, 0 0 20px rgba(0, 188, 212, 0.6), 0 2px 8px rgba(0,0,0,0.06);
  }
}
.tile:hover {
  transform: translateY(-4px) scale(1.03);
  box-shadow: 0 8px 24px rgba(0,0,0,0.12);
}
.tile img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  border-radius: 10px;
}
.tile-desc {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.78);
  color: #fff;
  opacity: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  height: 100%;
  padding: 8px 8px;
  text-align: center;
  transition: opacity 0.2s;
  font-size: 0.90em;
  line-height: 1.4;
}
.tile:hover .tile-desc,
.tile:focus .tile-desc {
  opacity: 1;
}
.tile-desc b {
  font-size: 1.1em;
  margin-bottom: 0.5em;
  display: block;
}
.tile-desc .level {
  font-size: 0.95em;
  margin-bottom: 0.5em;
  font-weight: bold;
  color: #fff;
}
.howtoplay {
  max-width: 900px;
  margin-top: 32px;
  margin-left: 4vw;
  margin-right: 4vw;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  padding: 24px 32px;
  text-align: center;
}
.howtoplay h1 {
  font-size: 2.2em;
}
.howtoplay h2{
  font-size: 1.8em;
}
.howtoplay p {
  font-size: 1.25em;
  line-height: 1.8;
  margin-left: 8px;
  margin-right: 8px;
}
.howtoplay h3 {
  font-size: 1.2em;
  font-weight: bold;
  margin: 20px 0 10px 0;
  color: #333;
}
.howtoplay, .contents-section, .updates {
  max-width: 900px;
  margin: 0 4vw 32px 4vw;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  text-align: center;
  padding-left: 4vw;
  padding-right: 4vw;
}

/* 上下margin/paddingは各セクションで個別指定 */
.howtoplay {
  margin-top: 32px;
  margin-bottom: 0;
  padding: 24px 0;
}
.contents-section {
  margin-top: 32px;
  margin-bottom: 0;
  padding: 24px 0;
}
.updates {
  margin-top: 20px;
  margin-bottom: 32px;
  padding: 12px 0;
}
  .updates h2 {
    margin-top: 0;
    margin-bottom: 8px;
    font-size: 1.1em;
  }
  .updates ul {
    padding-left: 0;
    margin-top: 0;
    margin-bottom: 0;
    list-style: none;
    display: flex;
    flex-direction: column;
    align-items: center;
  }
  .updates li {
    text-align: left;
    position: relative;
    padding-left: 1.2em;
    margin-bottom: 0.5em;
  }
  .updates li::before {
    content: "▶";
    position: absolute;
    left: 0;
    color: #666;
    font-size: 0.85em;
  }

@media (min-width: 900px) {
  .howtoplay, .contents-section, .updates {
    padding-left: 32px;
    padding-right: 32px;
  }
}
@media (min-width: 1200px) {
  .howtoplay, .contents-section, .updates {
    margin-left: auto;
    margin-right: auto;
  }
}
#noticePopup .popup-content {
  line-height: 1.8;
  
}
#noticePopup button {
  font-size: 1.15em;
  padding: 10px 32px;
  border-radius: 6px;
  background: #888;
  color: #fff;
  border: none;
  margin-top: 16px;
  cursor: pointer;
  font-weight: bold;
  transition: background 0.2s;
}
#noticePopup button:hover {
  background: #444;
}

/* フッター */
footer {
  background: #fff;
  border-top: 1px solid #e0e0e0;
  padding: 24px 16px;
  margin-top: 48px;
  text-align: center;
  color: #666;
  font-size: 0.9em;
}

footer p {
  margin: 8px 0;
  line-height: 1.6;
}

footer a {
  color: #222;
  text-decoration: none;
  border-bottom: 1px solid #ccc;
  transition: border-color 0.2s;
}

footer a:hover {
  border-bottom-color: #222;
}