* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Arial, Helvetica, sans-serif;
}

body {
  background: #f4f6f8;
  color: #333;
}

.header {
  background: #111827;
  color: #fff;
  padding: 15px 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.sidebar {
  width: 220px;
  background: #1f2933;
  height: 100vh;
  position: fixed;
  top: 60px;
  left: 0;
  padding-top: 20px;
}

.sidebar a {
  display: block;
  color: #cbd5e1;
  padding: 12px 20px;
  text-decoration: none;
}

.sidebar a:hover {
  background: #374151;
  color: #fff;
}

.content {
  margin-left: 220px;
  padding: 30px;
}

.card {
  background: #fff;
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 20px;
  box-shadow: 0 2px 6px rgba(0,0,0,.08);
}

.btn {
  background: #2563eb;
  color: #fff;
  border: none;
  padding: 10px 18px;
  border-radius: 6px;
  cursor: pointer;
}

.btn-danger {
  background: #dc2626;
}

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px,1fr));
  gap: 20px;
}

.stat {
  text-align: center;
}

.stat h2 {
  font-size: 28px;
  margin-bottom: 5px;
}

.list-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 0;
  border-bottom: 1px solid #e5e7eb;
}

.preview {
  background: #000;
  color: #fff;
  aspect-ratio: 16/9;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 32px;
  border-radius: 8px;
}