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

body {
  font-family: Arial, sans-serif;
    max-width: 1200px;
    margin: 0 auto;   /* centers the page */
    padding: 20px;
    font-size: 18px;
}

/* Header */
.site-header {
  background: #333;
  color: #fff;
  padding: 10px 20px;
}

/* Sidebar + content layout */
.layout {
  display: flex;
  height: calc(100vh - 50px);  /* full height minus header */
}

/* Left sidebar */
.sidebar {
  width: 250px;
  background: #f0f0f0;
  padding: 15px;
  font-size: 14px;
}

.sidebar ul {
  list-style: none;
}

.sidebar li {
  margin-bottom: 8px;
}

.sidebar a {
  text-decoration: none;
  color: #333;
}
a:hover {
  text-decoration: underline;
}
/* Right content area */
.content {
  flex: 1;
}

/* Make iframe fill the content area */
.content iframe {
  width: 100%;
  height: 100%;
  border: none;
  font-size: 18px;
}