body {
  font-family: Arial, sans-serif;
  margin: 0;
  background: #f4f4f9;
  color: #333;
  overflow-x: hidden;
}

header {
  text-align: center;
  padding: 2rem 1rem 1rem;
}

h2 {
  margin-top: 2.5rem;
  text-align: center;
  font-size: 1.5rem;
  color: #444;
}

.card {
  background: #fff;
  border-radius: 12px;
  padding: 0;
  text-align: center;
  cursor: pointer;
  overflow: hidden;
  position: relative;
  z-index: 1;
  transition: transform 0.3s ease;
  max-width: 350px;
  min-width: 200px;
  margin: 0 auto;
}

.card h3 {
  margin: 0.5rem 0;
  font-size: 1rem;
}

.card p {
  font-size: 0.75rem;
  margin: 0.25rem 0;
  color: #666;
}

.card iframe {
  width: 100%;
  height: calc(100% - 3rem);
  border: none;
  border-radius: 8px;
  display: none;
}

.card-close {
  position: absolute;
  top: 8px;
  right: 8px;
  width: 30px;
  height: 30px;
  border: none;
  background: rgba(0, 0, 0, 0.6);
  color: #fff;
  border-radius: 50%;
  cursor: pointer;
  display: none;
  z-index: 1010;
  padding: 0;
  align-items: center;
  justify-content: center;
}

.preview-wrapper {
  width: 100%;
  height: calc(100% - 3rem);
  border-radius: 8px;
  overflow: hidden;
  position: relative;
  overflow: auto;
  -webkit-overflow-scrolling: touch;
}

.preview-img,
.preview-iframe {
  width: 100%;
  border: none;
  display: none;
}

.github-button {
  position: absolute;
  bottom: 10px;
  right: 10px;
  background: #24292e;
  color: #fff;
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  font-size: 0.8rem;
  text-decoration: none;
  z-index: 1001;
  display: none;
}

.overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.3);
  z-index: 999;
}

.overlay.active {
  display: block;
}