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

body {
  font-family: 'Segoe UI', sans-serif;
  background-color: #f9f9f9;
  color: #333;
}

header {
  background-color: #4a90e2;
  color: white;
  padding: 20px;
  text-align: center;
  font-size: 24px;
  font-weight: bold;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.container {
  display: flex;
  height: calc(100vh - 70px);
}

.sidebar {
  width: 220px;
  background-color: #ffffff;
  border-right: 1px solid #e0e0e0;
  padding: 20px;
}

.sidebar h2 {
  font-size: 18px;
  margin-bottom: 20px;
  color: #4a90e2;
}

.sidebar a {
  display: block;
  padding: 10px;
  margin-bottom: 10px;
  background-color: #f1f1f1;
  border-radius: 6px;
  color: #333;
  text-decoration: none;
  transition: background-color 0.2s;
}

.sidebar a:hover {
  background-color: #e0e0e0;
}

.content {
  flex: 1;
  background-color: #fff;
}

iframe {
  width: 100%;
  height: 100%;
  border: none;
}