body {
  font-family: sans-serif;
  margin: 0;
  padding: 0;
  background-color: #f4f4f4;
  color: #333;
}

header {
  background-color: #0077cc;
  color: white;
  padding: 1em;
  text-align: center;
  position: sticky; /* ← スクロールで固定される */
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
}

main {
  padding: 2em;
  max-width: 700px;
  margin: auto;
  background-color: white;
  margin-top: 2em;
}

h2 {
  border-bottom: 2px solid #0077cc;
  padding-bottom: 0.3em;
}

ul {
  padding-left: 1.5em;
}

footer {
  text-align: center;
  font-size: 0.9em;
  color: gray;
  margin-top: 2em;
}

/* ✅ 自己紹介は普通のブロック */
.profile {
  background: white;
  padding: 2em;
  text-align: center;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
  margin-top: 80px; /* ヘッダーの高さ分だけ余白 */
}
.profile img {
  max-width: 120px;
  border-radius: 50%;
  display: block;
  margin: 0 auto 1em;
}
.profile-title {
  font-size: 1.4em;
  margin-bottom: 0.5em;
  color: #0077cc;
}

/* アコーディオン */
.accordion-btn {
  width: 100%;
  padding: 1em;
  background: #0077cc;
  color: white;
  border: none;
  text-align: left;
  cursor: pointer;
  font-size: 1.1em;
  margin-top: 0.5em;
  border-radius: 5px;
  transition: background 0.3s;
}
.accordion-btn:hover {
  background: #005fa3;
}
.accordion-btn[aria-expanded="true"] {
  background: #005fa3;
}
.accordion-panel {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.4s ease;
  background: #f9f9f9;
  padding: 0 1em;
  border-radius: 5px;
}
.accordion-panel.show {
  max-height: 1000px;
  padding: 1em;
}