body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f4f7f6; margin: 0; display: flex; }
.sidebar { width: 250px; background-color: #2c3e50; color: white; height: 100vh; position: fixed; }
.sidebar h2 { text-align: center; padding: 20px 0; border-bottom: 1px solid #34495e; }
.sidebar ul { list-style: none; padding: 0; }
.sidebar ul li { padding: 15px 20px; border-bottom: 1px solid #34495e; cursor: pointer; transition: 0.3s; }
.sidebar ul li:hover { background-color: #34495e; }
.sidebar ul li a { color: white; text-decoration: none; display: block; }
.main-content { margin-left: 250px; padding: 30px; width: 100%; }
.card { background: white; padding: 20px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); margin-bottom: 20px; }
.stats-container { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px; }
.stat-card { background: #fff; padding: 20px; border-radius: 8px; text-align: center; border-left: 5px solid #3498db; }
.stat-card.sales { border-left-color: #2ecc71; }
.stat-card.expenses { border-left-color: #e74c3c; }
table { width: 100%; border-collapse: collapse; margin-top: 20px; }
th, td { padding: 12px; text-align: left; border-bottom: 1px solid #ddd; }
th { background-color: #f8f9fa; }
.btn { padding: 10px 15px; border: none; border-radius: 4px; cursor: pointer; text-decoration: none; color: white; }
.btn-primary { background-color: #3498db; }
.btn-success { background-color: #2ecc71; }
.form-group { margin-bottom: 15px; }
.form-group label { display: block; margin-bottom: 5px; }
.form-group input, .form-group select, .form-group textarea { width: 100%; padding: 8px; border: 1px solid #ddd; border-radius: 4px; }