body {
  font-family: Arial, Helvetica, sans-serif;
  background: linear-gradient(135deg, #f8f9fa 0%, #e3ecec 100%);
  margin: 0;
  padding: 0;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 2rem;
  text-align: center;
}

h1 {
  color: #333;
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.slides {
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  border-radius: 4px;
  overflow: hidden;
}

.pdf-container {
  position: relative;
}

.page-wrapper {
  position: relative;
}

.slide-link {
  position: absolute;
  top: 43%;
  left: 4%;
  width: 52%;
  height: 38%;
  display: block;
  cursor: pointer;
  text-decoration: none;
  border: 2px solid rgba(255, 0, 0, 0.6);
  box-sizing: border-box;
}

#pdf-viewer {
  width: 100%;
}

.pdf-page {
  width: 100%;
  height: auto;
  display: block;
  margin-bottom: 1rem;
}
nav {
  margin-bottom: 1rem;
  position: relative;
  z-index: 10;
}

.tabs {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  justify-content: center;
  gap: 0.5rem;
}

.tabs > li {
  position: relative;
}

.tabs > li > a,
.tabs > li > span {
  display: block;
  padding: 0.5rem 1rem;
  text-decoration: none;
  background: #fff;
  color: #333;
  border-radius: 4px;
}

.tabs > li > span {
  cursor: pointer;
}

.tabs > li > a:hover,
.submenu a:hover {
  background: #eee;
}

.dropdown .submenu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  z-index: 1000;
  list-style: none;
  margin: 0;
  padding: 0.25rem 0;
  background: #fff;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.dropdown:hover .submenu {
  display: block;
}

.dropdown.open .submenu {
  display: block;
}

.submenu li a {
  display: block;
  padding: 0.5rem 1rem;
  white-space: nowrap;
  text-decoration: none;
  color: #555;
  font-size: 0.9rem;
}