/* ====== 共通スタイル ====== */
body {
  margin: 0;
  font-family: 'Helvetica Neue', sans-serif;
  background-color: #d0d0d0;
  color: #333;
}

/* ====== ヘッダー（PCデフォルト表示） ====== */
.site-header {
  background-color: #222;
  padding: 10px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
}

.site-header .logo {
  height: 40px;
}

.main-nav {
  display: flex;
  align-items: center;
}

.main-nav a {
  color: white;
  text-decoration: none;
  margin-left: 15px;
  font-weight: bold;
}

.main-nav a:hover {
  text-decoration: underline;
}

/* ====== ハンバーガー（スマホのみ） ====== */
.hamburger {
  display: none;
}

/* ====== 講師プロフィールセクション ====== */
.instructor-profile {
  max-width: 900px;
  margin: 20px auto;
  padding: 20px 20px 0;
  background-color: #fff;
  border-radius: 8px;
}

.instructor-profile img {
  width: 100%;
  max-width: 300px;
  height: auto;
  border-radius: 10px;
  display: block;
  margin: 0 auto 20px;
}

.instructor-name {
  margin-top: -15px;
  font-weight: 900;
  font-size: 2.5rem;
  text-align: center;
  color: #222;
}

/* ====== プロフィール項目グリッド ====== */
.profile-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin: 20px;
}

.profile-card {
  background-color: #ffffff;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 0 5px rgba(0,0,0,0.1);
}

.profile-card h2 {
  font-size: 1.2rem;
  margin-bottom: 10px;
  color: #222;
  border-left: 4px solid #ffcc00;
  padding-left: 10px;
}

/* ====== 動画セクション ====== */
.video-section {
  margin: 40px 20px;
}

.video-section h2 {
  font-size: 1.5rem;
  margin-bottom: 15px;
  text-align: center;
}

.video-container {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  max-width: 100%;
  border-radius: 12px;
}

.video-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

/* ====== スライダー下部講師一覧 ====== */
.instructor-slider {
  background-color: #d0d0d0;
  padding: 30px 20px;
}

.instructor-slider h2 {
  font-size: 1.5rem;
  margin-bottom: 15px;
  text-align: center;
  color: #333;
}

.slider-wrapper {
  overflow-x: auto;
  overflow-y: hidden;
  -webkit-overflow-scrolling: touch;
  white-space: nowrap;
}

.slider {
  display: flex;
  gap: 15px;
  scroll-snap-type: x mandatory;
  padding-bottom: 10px;
  width: 100%; /* ← 横幅を制限 */
  overflow-x: auto; /* ← 保険的に再指定 */
}

.slider a {
  flex: 0 0 auto;
  scroll-snap-align: start;
  text-decoration: none;
}


.slider img {
  width: 100%;
  height: auto;
  max-width: 180px;
  border-radius: 10px;
  display: block;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  transition: transform 0.3s;
}

.slider img:hover {
  transform: scale(1.05);
}

/* ====== スマホ用調整 ====== */
@media (max-width: 768px) {
  .hamburger {
    display: flex;
    flex-direction: column;
    cursor: pointer;
  }

  .hamburger span {
    background: white;
    height: 3px;
    margin: 4px 0;
    width: 25px;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background-color: #222;
    flex-direction: column;
    text-align: center;
    z-index: 1000;
  }

  .main-nav.active {
    display: flex;
  }

  .main-nav a {
    margin: 10px 0;
  }

  .profile-grid {
    grid-template-columns: 1fr;
    margin: 20px 10px;
  }

  .slider {
    gap: 6px;
  }

  .slider a {
    flex: 0 0 33.3%;
  }

  .slider img {
    max-width: 140px;
  }
}