* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #f0f4f8;
    color: #333;
    line-height: 1.6;
}
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}
.navbar {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 15px 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}
.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    color: #fff;
    font-size: 24px;
    font-weight: bold;
    text-decoration: none;
}
.nav-links {
    list-style: none;
    display: flex;
    gap: 25px;
}
.nav-links a {
    color: #fff;
    text-decoration: none;
    font-size: 16px;
    transition: opacity 0.3s;
}
.nav-links a:hover {
    opacity: 0.8;
}
main {
    min-height: 60vh;
    padding: 40px 0;
}
footer {
    background: #2d3748;
    color: #fff;
    text-align: center;
    padding: 20px 0;
}
h1 {
    font-size: 32px;
    margin-bottom: 20px;
    color: #2d3748;
}
h2 {
    font-size: 24px;
    margin-bottom: 15px;
    color: #4a5568;
}
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
    margin-top: 30px;
}
.card {
    background: #fff;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
}
.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.12);
}
.card h3 {
    font-size: 20px;
    margin-bottom: 10px;
    color: #667eea;
}
.card p {
    color: #666;
    margin-bottom: 8px;
}
.btn {
    display: inline-block;
    background: #667eea;
    color: #fff;
    padding: 10px 20px;
    border-radius: 6px;
    text-decoration: none;
    transition: background 0.3s;
}
.btn:hover {
    background: #5a67d8;
}
.admin-table {
    width: 100%;
    border-collapse: collapse;
    background: #fff;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}
.admin-table th, .admin-table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #e2e8f0;
}
.admin-table th {
    background: #667eea;
    color: #fff;
}
.admin-table tr:hover {
    background: #f7fafc;
}
.form-group {
    margin-bottom: 15px;
}
.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
    color: #4a5568;
}
.form-group input, .form-group textarea, .form-group select {
    width: 100%;
    padding: 10px;
    border: 1px solid #cbd5e0;
    border-radius: 6px;
    font-size: 14px;
}
.form-actions {
    display: flex;
    gap: 10px;
    margin-top: 15px;
}
.alert {
    padding: 12px;
    border-radius: 6px;
    margin-bottom: 15px;
}
.alert-success {
    background: #c6f6d5;
    color: #22543d;
}
.alert-error {
    background: #fed7d7;
    color: #822727;
}
@media (max-width: 768px) {
    .navbar .container {
        flex-direction: column;
        gap: 10px;
    }
    .nav-links {
        flex-wrap: wrap;
        justify-content: center;
    }
}