:root {
    --primary-color: #2c3e50;
    --secondary-color: #e67e22;
    --accent-color: #3498db;
    --bg-color: #f8f9fa;
    --text-color: #333;
    --card-bg: #ffffff;
    --success-color: #2ecc71;
    --danger-color: #e74c3c;
    --info-color: #17a2b8;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --border-radius: 8px;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 0;
    line-height: 1.6;
}

/* Layout */
.wrapper {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    background-color: var(--primary-color);
    color: white;
    padding: 1rem 0;
    box-shadow: var(--shadow);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.brand {
    font-size: 1.5rem;
    font-weight: bold;
    color: white;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 20px;
    margin: 0;
    padding: 0;
}

.nav-links a {
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: var(--secondary-color);
}

.main-content {
    flex: 1;
    max-width: 1200px;
    margin: 40px auto;
    padding: 0 20px;
    width: 100%;
    box-sizing: border-box;
}

/* Cards */
.card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 30px;
    margin-bottom: 20px;
}

.card-header {
    margin-bottom: 20px;
    border-bottom: 2px solid var(--bg-color);
    padding-bottom: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card-title {
    margin: 0;
    color: var(--primary-color);
}

/* Forms */
.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
input[type="date"],
select,
textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    box-sizing: border-box;
    font-size: 1rem;
}

input:focus, select:focus {
    outline: none;
    border-color: var(--accent-color);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 10px 20px;
    background-color: var(--secondary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    text-decoration: none;
    font-size: 1rem;
    transition: background 0.3s, transform 0.1s;
}

.btn:hover {
    background-color: #d35400;
}

.btn:active {
    transform: translateY(1px);
}

.btn-block {
    display: block;
    width: 100%;
}

.btn-danger {
    background-color: var(--danger-color);
}
.btn-danger:hover { background-color: #c0392b; }

.btn-success {
    background-color: var(--success-color);
}
.btn-success:hover { background-color: #27ae60; }

.btn-secondary {
    background-color: #95a5a6;
}
.btn-secondary:hover { background-color: #7f8c8d; }

.btn-info {
    background-color: var(--info-color);
}
.btn-info:hover { background-color: #138496; }

.btn-primary {
    background-color: var(--accent-color);
}
.btn-primary:hover { background-color: #2980b9; }

.btn-sm {
    padding: 5px 10px;
    font-size: 0.85rem;
}

/* Tables */
.table-responsive {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 10px;
}

th, td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid #eee;
}

th {
    background-color: var(--primary-color);
    color: white;
    font-weight: 600;
}

tr:hover {
    background-color: #f1f1f1;
}

/* Utilities */
.text-center { text-align: center; }
.mt-4 { margin-top: 1.5rem; }
.mb-4 { margin-bottom: 1.5rem; }
.flex { display: flex; gap: 10px; }
.justify-between { justify-content: space-between; }

.alert {
    padding: 15px;
    border-radius: var(--border-radius);
    margin-bottom: 20px;
    color: white;
    background-color: var(--accent-color);
}

.alert-success { background-color: var(--success-color); }
.alert-error { background-color: var(--danger-color); }

/* Login Specific */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
}

.login-box {
    background: white;
    padding: 40px;
    border-radius: var(--border-radius);
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
    width: 100%;
    max-width: 400px;
}

/* Print */
@media print {
    header, .btn, .card-header, .alert, .form-group {
        display: none !important;
    }
    
    .main-content {
        margin: 0;
        padding: 0;
    }
    
    .card {
        box-shadow: none;
        padding: 0;
    }
    
    table {
        font-size: 12px;
    }
    
    th, td {
        padding: 5px;
    }
}