* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: Arial, sans-serif;
  background: #f0f2f5;
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

h1 {
  text-align: center;
  color: #1a73e8;
  margin-bottom: 30px;
}

.search-box {
  margin-bottom: 20px;
}

#searchInput {
  width: 100%;
  padding: 12px;
  border: 2px solid #dfe1e5;
  border-radius: 24px;
  font-size: 16px;
  outline: none;
  transition: all 0.3s;
}

#searchInput:focus {
  border-color: #1a73e8;
  box-shadow: 0 1px 6px rgba(32,33,36,.28);
}

.links-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 20px;
}

.link-card {
  background: white;
  padding: 15px;
  border-radius: 8px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.12);
  transition: all 0.3s;
  cursor: pointer;
}

.link-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.link-number {
  font-weight: bold;
  color: #1a73e8;
  margin-bottom: 5px;
}

.popup {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.7);
  z-index: 1000;
}

.popup-content {
  position: relative;
  width: 90%;
  height: 90%;
  margin: 2% auto;
  background: white;
  border-radius: 8px;
  padding: 20px;
}

.close-btn {
  position: absolute;
  top: 10px;
  right: 20px;
  font-size: 30px;
  cursor: pointer;
  color: #666;
}

#popupFrame {
  width: 100%;
  height: 95%;
  border: none;
}

.nav-menu {
  background: #1a73e8;
  padding: 15px;
  text-align: center;
  margin-bottom: 20px;
}

.nav-menu a {
  color: white;
  text-decoration: none;
  padding: 8px 15px;
  margin: 0 5px;
  border-radius: 4px;
  transition: background 0.3s;
}

.nav-menu a:hover {
  background: rgba(255,255,255,0.1);
}

.nav-menu a.active {
  background: rgba(255,255,255,0.2);
  font-weight: bold;
}