/* ===== 昔のホームページ風スタイル ===== */

body {
  background-color: #000080;
  background-image: url("data:image/svg+xml,%3Csvg width='4' height='4' viewBox='0 0 4 4' xmlns='http://www.w3.org/2000/svg'%3E%3Crect x='0' y='0' width='2' height='2' fill='%23000070' /%3E%3Crect x='2' y='2' width='2' height='2' fill='%23000070' /%3E%3C/svg%3E");
  color: #ffffff;
  font-family: "MS Gothic", "ＭＳ ゴシック", monospace;
  margin: 0;
  padding: 8px;
}

h1 {
  text-align: center;
  font-size: 2.4rem;
  color: #ffff00;
  border-top: 3px ridge #c0c0c0;
  border-bottom: 3px ridge #c0c0c0;
  padding: 6px 0;
}

h2 {
  margin-left: 10%;
  color: #ffff00;
  padding: 6px 0;
}

hr {
  border: 3px solid #c0c0c0;
}

/* ===== 全体レイアウト ===== */

.layout {
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

/* ===== メインコンテンツ ===== */

.main-content {
  flex: 1;
  min-width: 50%;
}

.img-grid {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.img-left {
  width: calc(30% - 1rem);
  height: auto;
  position: relative;
  z-index: 2;
  margin-right: -5rem;
}

.img-center {
  width: 20%;
  height: 20%;
  margin-top: 10%;
  position: relative;
  z-index: 1;
  border-radius: 40%;
}

.img-right {
  width: calc(30% - 1rem);
  height: auto;
  position: relative;
  z-index: 2;
  margin-left: -5rem;
}

a {
  display: contents;
}

/* ===== スポンサードリンク ===== */

.sponsor {
  width: 200px;
  flex-shrink: 0;
  background-color: #ffffff;
  border: 3px ridge #c0c0c0;
  padding: 6px;
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.sponsor-label {
  font-size: 0.65rem;
  color: #333333;
  margin: 0;
  text-align: center;
  border-bottom: 1px solid #c0c0c0;
  padding-bottom: 4px;
  width: 100%;
}

.sponsor a {
  display: block;
}

.sponsor a img {
  width: 100%;
  height: auto;
  display: block;
  border: 1px solid #c0c0c0;
}

.sponsor-left {
  margin-top: 100px;
}

.sponsor-right {
  margin-top: 200px;
}

@keyframes marquee {
  0% {
    transform: translateX(100%);
  }

  100% {
    transform: translateX(-100%);
  }
}

.marquee {
  animation: marquee 10s linear infinite;
}

/* ===== スマホでは非表示 ===== */

@media (max-width: 600px) {
  .sponsor {
    display: none;
  }

  .img-left,
  .img-center,
  .img-right {
    width: 35%;
  }
}