:root {
    --primary-blue: #003366;
    --secondary-blue: #288cfa;
    --background: #F5F5F5;
    --text-primary: #242c34;
    --success-green: #2E865F;
    --warning-amber: #FF9800;
    --error-red: #D32F2F;
    --white: #ffffff;
    --gray-light: #e0e0e0;
    --gray: #9e9e9e;
}

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

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
.navbar {
    background: var(--primary-blue);
    color: var(--white);
    padding: 1rem 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--white);
    text-decoration: none;
}

.nav-links {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-links a {
    color: var(--white);
    text-decoration: none;
    transition: color 0.3s;
}

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 4px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
}

.btn-primary {
    background: var(--primary-blue);
    color: var(--white);
}

.btn-primary:hover {
    background: var(--secondary-blue);
}

.btn-success {
    background: var(--success-green);
    color: var(--white);
}

.btn-warning {
    background: var(--warning-amber);
    color: var(--white);
}

.btn-danger {
    background: var(--error-red);
    color: var(--white);
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
}

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--gray-light);
    border-radius: 4px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-control:focus {
    outline: none;
    border-color: var(--secondary-blue);
}

/* Cards */
.card {
    background: var(--white);
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.card-header {
    border-bottom: 1px solid var(--gray-light);
    padding-bottom: 1rem;
    margin-bottom: 1rem;
}

.card-header h2 {
    color: var(--primary-blue);
    font-size: 1.25rem;
}

/* Dashboard Grid */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.stat-card {
    background: var(--white);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    text-align: center;
}

.stat-value {
    font-size: 2rem;
    font-weight: bold;
    color: var(--primary-blue);
    margin: 0.5rem 0;
}

.stat-label {
    color: var(--gray);
    font-size: 0.875rem;
}

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

.table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
}

.table th,
.table td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--gray-light);
}

.table th {
    background: var(--primary-blue);
    color: var(--white);
    font-weight: 500;
}

.table tr:hover {
    background: rgba(40, 140, 250, 0.05);
}

/* Status Badges */
.badge {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 500;
}

.badge-success {
    background: var(--success-green);
    color: var(--white);
}

.badge-warning {
    background: var(--warning-amber);
    color: var(--white);
}

.badge-danger {
    background: var(--error-red);
    color: var(--white);
}

/* Alerts */
.alert {
    padding: 1rem;
    border-radius: 4px;
    margin: 1rem 0;
}

.alert-success {
    background: rgba(46, 134, 95, 0.1);
    border: 1px solid var(--success-green);
    color: var(--success-green);
}

.alert-danger {
    background: rgba(211, 47, 47, 0.1);
    border: 1px solid var(--error-red);
    color: var(--error-red);
}

.alert-warning {
    background: rgba(255, 152, 0, 0.1);
    border: 1px solid var(--warning-amber);
    color: var(--warning-amber);
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
}

.modal-content {
    background: var(--white);
    margin: 10% auto;
    padding: 2rem;
    border-radius: 8px;
    max-width: 500px;
    position: relative;
}

.close {
    position: absolute;
    right: 1rem;
    top: 1rem;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--gray);
}

.close:hover {
    color: var(--text-primary);
}

/* Loading Spinner */
.spinner {
    border: 3px solid var(--gray-light);
    border-top: 3px solid var(--primary-blue);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 20px auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .dashboard-grid {
        grid-template-columns: 1fr;
    }
    
    .modal-content {
        margin: 20% 20px;
        width: auto;
    }
}