body {
  font-family: 'Arial', sans-serif;
  margin: 0;
  padding: 0;
  background: #fff;
}

header {
  text-align: center;
  padding: 2rem;
  background-color: #76a3de;
  color:#fff;
}

.category-tabs {
  display: flex;
  justify-content: center;
  gap: 1rem;
  padding: 1rem;
  background-color: #eee;
}

.category-tabs button {
  padding: 0.5rem 1rem;
  border: none;
  background-color: #ddd;
  cursor: pointer;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr); /* 常に4列 */
  gap: 2rem;
  padding: 2rem;
}

@media (max-width: 768px) {
  .video-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}


.video-card {
  background-color: #fff7f7;
  padding: 1rem;
  border-radius: 8px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
  text-align: center;
}

.video-card img {
  max-width: 100%;
  height: auto;
  border-radius: 4px;
}

.btn {
  display: inline-block;
  margin-top: 1rem;
  padding: 0.6rem 0.8rem;
  background-color: #ca0032;
  color: #fff;
  text-decoration: none;
  border-radius: 4px;
  font-weight: bold;
  font-size: small;
  transition: background-color 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
}

.btn:hover {
  background-color: #A5090C;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.btn2 {
  display: inline-block;
  padding: 0.6rem 0.8rem;
  background-color: #ca0032;
  color: #fff;
  text-decoration: none;
  border-radius: 4px;
  font-weight: bold;
  font-size: small;
  transition: background-color 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
}

.btn2:hover {
  background-color: #A5090C;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.iframeWrap-video {
  position: relative;
  width: 100%;
  max-width: 100%;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
}

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

.taC {
  text-align: center !important;
}

.ttl_jp{
font-size: 30px;
color: #ca0032;
font-weight: bold;
display: inline-block;
border-bottom: 2px solid #ca0032;
padding-bottom: 10px;
padding-top: 10px;
margin-left: 30px;
}

.taD {
  font-size: larger;
}

.resizeimage {
   max-width: 2000px; /* 最大幅 */
}
.resizeimage img { width: 100%; }