:root {
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --danger-color: #e74c3c;
    --text-color: #2c3e50;
    --light-bg: #f5f7fa;
    --border-radius: 8px;
    --box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

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

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

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

/* Navigation Bar */
.navbar {
    background: white;
    padding: 1rem;
    box-shadow: var(--box-shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

/* Modern Cards */
.card {
    background: white;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--box-shadow);
    transition: transform 0.3s ease;
}

.card:hover {
    transform: translateY(-2px);
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

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

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(52,152,219,0.2);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

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

.btn-primary:hover {
    background: #2980b9;
    transform: translateY(-1px);
}

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

.btn-danger:hover {
    background: #c0392b;
}

/* Table Styling */
.table-container {
    overflow-x: auto;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

table {
    width: 100%;
    border-collapse: collapse;
}

th {
    background: var(--primary-color);
    color: white;
    padding: 1rem;
    text-align: left;
}

td {
    padding: 1rem;
    border-bottom: 1px solid #eee;
}

tr:hover {
    background: #f8f9fa;
}

/* Search Box */
.search-box {
    background: white;
    padding: 1rem;
    border-radius: var(--border-radius);
    margin-bottom: 1.5rem;
    box-shadow: var(--box-shadow);
}

.search-input {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .card {
        padding: 1rem;
    }
    
    .btn {
        width: 100%;
        margin-bottom: 0.5rem;
    }
    
    .table-container {
        margin: 0 -10px;
        border-radius: 0;
    }
    
    th, td {
        padding: 0.75rem;
    }
    
    .form-group {
        margin-bottom: 1rem;
    }
    
    /* Stack form elements on mobile */
    .form-row {
        flex-direction: column;
    }
    
    .form-row > * {
        width: 100%;
        margin-right: 0;
        margin-bottom: 1rem;
    }
}

/* Loading States */
.loading {
    position: relative;
    opacity: 0.7;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 2rem;
    height: 2rem;
    border: 3px solid #f3f3f3;
    border-top: 3px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: translate(-50%, -50%) rotate(0deg); }
    100% { transform: translate(-50%, -50%) rotate(360deg); }
}

/* Toast Notifications */
.toast {
    position: fixed;
    bottom: 20px;
    right: 20px;
    padding: 1rem 1.5rem;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    animation: slideIn 0.3s ease;
}

.toast-success {
    border-left: 4px solid var(--secondary-color);
}

.toast-error {
    border-left: 4px solid var(--danger-color);
}

@keyframes slideIn {
    from { transform: translateX(100%); }
    to { transform: translateX(0); }
}