* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Segoe UI', Roboto, sans-serif; background: #fff; color: #333; line-height: 1.6; }
.container { display: flex; min-height: 100vh; }
.sidebar { width: 240px; background: #f5f5f5; border-right: 1px solid #ddd; padding: 20px; }
.sidebar .logo { display: flex; align-items: center; gap: 10px; margin-bottom: 30px; }
.sidebar .logo img { width: 40px; height: 40px; object-fit: contain; }
.sidebar .logo h1 { font-size: 1.2rem; font-weight: 500; }
.sidebar nav ul { list-style: none; }
.sidebar nav ul li { margin-bottom: 10px; }
.sidebar nav ul li a { display: block; padding: 8px 12px; color: #333; text-decoration: none; border-radius: 4px; }
.sidebar nav ul li a:hover, .sidebar nav ul li a.active { background: #e0e0e0; }
.content { flex: 1; padding: 30px; }
h2 { font-weight: 400; margin-bottom: 20px; border-bottom: 1px solid #eee; padding-bottom: 10px; }
.card { background: #fff; border: 1px solid #eee; border-radius: 6px; padding: 20px; margin-bottom: 20px; }
.btn { display: inline-block; background: #007bff; color: #fff; border: none; padding: 8px 16px; border-radius: 4px; cursor: pointer; text-decoration: none; font-size: 14px; }
.btn-secondary { background: #6c757d; }
table { width: 100%; border-collapse: collapse; }
table th, table td { text-align: left; padding: 12px 8px; border-bottom: 1px solid #eee; }
table th { font-weight: 500; color: #777; }
input, select, textarea { width: 100%; padding: 8px; border: 1px solid #ddd; border-radius: 4px; margin-bottom: 15px; font-family: inherit; }
label { font-weight: 500; display: block; margin-bottom: 5px; }
.modal { display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.5); align-items: center; justify-content: center; }
.modal.show { display: flex; }
.modal-content { background: #fff; width: 500px; max-width: 90%; border-radius: 6px; padding: 25px; }
.modal-content h3 { margin-bottom: 15px; }
.login-page { display: flex; justify-content: center; align-items: center; height: 100vh; }
.login-box { background: #f9f9f9; border: 1px solid #ddd; padding: 40px; width: 360px; border-radius: 6px; }
.login-box h2 { border: none; text-align: center; }
.error { color: #dc3545; margin-bottom: 15px; text-align: center; }