body {
  margin: 0;
  font-family: "MS UI Gothic", "ＭＳ ゴシック", monospace;
  background: #008080;
  color: #000;
}
p {
  line-height: 1.75em;
}
.wrapper {
  max-width: 1000px;
  margin: auto;
  padding: 8px;
}

.box {
  border: 3px ridge #c0c0c0;
  background: #e0e0e0;
  padding: 10px;
  margin-bottom: 10px;
}

header {
  background: navy;
  color: white;
  text-align: center;
  padding: 16px;
  border: 5px ridge #fff;
  margin-bottom: 10px;
}

header h1 {
  margin: 0;
  font-size: 28px;
  letter-spacing: 2px;
}

.blink {
  animation: blink 1.5s steps(2, start) infinite;
}
@keyframes blink {
  to {
    visibility: hidden;
  }
}

.layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 10px;
}

nav ul {
  list-style: none;
  padding: 0;
  margin: 10px 0;
}

nav li {
  margin-bottom: 6px;
}

nav ul a {
  display: block;
  background: #c0c0ff;
  padding: 6px;
  text-decoration: none;
  border: 2px outset #fff;
  color: black;
  font-weight: bold;
}

nav ul a:hover {
  background: yellow;
}

main {
  background: white;
  padding: 12px;
  border: 3px inset #aaa;
}

footer {
  text-align: center;
  font-size: 12px;
  padding: 8px;
}

.counter {
  font-family: monospace;
  background: black;
  color: lime;
  padding: 4px 8px;
  display: inline-block;
}

@media (max-width: 700px) {
  .layout {
    grid-template-columns: 1fr;
  }

  nav {
    order: 2;
  }

  main {
    order: 1;
  }

  header h1 {
    font-size: 20px;
  }
}

blockquote {
  margin: 10px 0;
  padding: 10px;
  background: #f0f0f0;
  border-left: 6px solid #808080;
  font-size: 14px;
}

blockquote::before {
  content: "＞ ";
  font-weight: bold;
  color: #555;
}

code {
  font-family: "Courier New", monospace;
  background: #222;
  color: #00ff00;
  padding: 2px 4px;
  border: 1px solid #555;
  font-size: 13px;
}

pre {
  background: black;
  color: #00ff00;
  font-family: "Courier New", monospace;
  padding: 10px;
  border: 2px inset #888;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.4;
  white-space: pre-line;
}

pre code {
  background: transparent;
  border: none;
  padding: 0;
  color: inherit;
}
.members {
  border: 2px ridge #c0c0c0;
}
.members th,
.members td {
  border: 2px ridge #ffffff; /* セルの枠線は太さ1ピクセル */
}
.members img {
  max-width: 200px;
  height: auto;
}