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

body {
    font-family: 'Arial', sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

.container {
    width: 80%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: linear-gradient(135deg, #2c3e50, #3498db);
    color: white;
    padding: 60px 0;
    text-align: center;
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

header p {
    font-size: 1.2em;
    opacity: 0.9;
}

nav {
    background-color: #34495e;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
}

nav ul li {
    margin: 0 10px;
}

nav ul li a {
    display: block;
    padding: 15px 20px;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
}

nav ul li a:hover {
    background-color: #2c3e50;
    border-radius: 5px;
}

.section {
    padding: 60px 0;
}

.section:nth-child(even) {
    background-color: #ecf0f1;
}

.section h2 {
    text-align: center;
    margin-bottom: 40px;
    color: #2c3e50;
    font-size: 2em;
}

.server-banner {
    text-align: center;
    margin: 30px 0;
}

.server-banner img {
    max-width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.info-card {
    background-color: white;
    padding: 30px;
    margin: 20px 0;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.info-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0,0,0,0.15);
}

.info-card h3 {
    color: #3498db;
    margin-bottom: 15px;
    font-size: 1.3em;
}

.info-card ul {
    list-style: none;
    padding-left: 20px;
}

.info-card ul li {
    position: relative;
    padding-left: 20px;
    margin: 10px 0;
}

.info-card ul li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: #3498db;
    font-size: 1.2em;
}

.card-system {
    display: flex;
    flex-wrap: wrap;
    gap: 30px;
    justify-content: center;
}

.card-input, .card-info {
    flex: 1;
    min-width: 300px;
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.card-input h3, .card-info h3 {
    color: #3498db;
    margin-bottom: 20px;
    font-size: 1.3em;
}

.card-input input {
    width: 100%;
    padding: 12px;
    margin-bottom: 20px;
    border: 2px solid #ddd;
    border-radius: 5px;
    font-size: 1em;
}

.card-input input:focus {
    outline: none;
    border-color: #3498db;
}

.card-input button {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 5px;
    font-size: 1em;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.card-input button:hover {
    background-color: #2980b9;
}

#verify-result {
    margin-top: 20px;
    padding: 15px;
    border-radius: 5px;
    font-weight: bold;
}

#verify-result.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

#verify-result.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.admin-login, .admin-panel {
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    max-width: 600px;
    margin: 0 auto;
}

.admin-login h3, .admin-panel h3 {
    color: #3498db;
    margin-bottom: 20px;
    font-size: 1.3em;
}

.admin-login input {
    width: 100%;
    padding: 12px;
    margin-bottom: 20px;
    border: 2px solid #ddd;
    border-radius: 5px;
    font-size: 1em;
}

.admin-login input:focus {
    outline: none;
    border-color: #3498db;
}

.admin-login button, .admin-panel button {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 5px;
    font-size: 1em;
    cursor: pointer;
    transition: background-color 0.3s ease;
    margin-right: 10px;
    margin-bottom: 10px;
}

.admin-login button:hover, .admin-panel button:hover {
    background-color: #2980b9;
}

#login-result {
    margin-top: 20px;
    padding: 15px;
    border-radius: 5px;
    font-weight: bold;
}

#login-result.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

#login-result.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.admin-section {
    margin: 30px 0;
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 5px;
}

.admin-section h4 {
    color: #2c3e50;
    margin-bottom: 15px;
    font-size: 1.1em;
}

.card-setting {
    margin-bottom: 20px;
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.card-setting input {
    flex: 1;
    min-width: 200px;
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: 5px;
    font-size: 1em;
}

.card-setting input:focus {
    outline: none;
    border-color: #3498db;
}

.card-setting button {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 5px;
    font-size: 1em;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.delete-card {
    background-color: #e74c3c;
    color: white;
    border: none;
    padding: 5px 10px;
    border-radius: 3px;
    font-size: 0.8em;
    cursor: pointer;
    transition: background-color 0.3s ease;
    margin-left: 10px;
}

.delete-card:hover {
    background-color: #c0392b;
}

.card-list-user {
    flex: 1;
    min-width: 300px;
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.card-list-user h3 {
    color: #3498db;
    margin-bottom: 20px;
    font-size: 1.3em;
}

.card-list-user ul {
    list-style: none;
}

.card-list-user ul li {
    padding: 10px;
    border-bottom: 1px solid #eee;
    margin-bottom: 10px;
}

.card-list-user ul li:last-child {
    border-bottom: none;
}

#card-list {
    margin-top: 20px;
    padding: 15px;
    background-color: #f0f8ff;
    border-radius: 5px;
    max-height: 300px;
    overflow-y: auto;
}

#status-result {
    margin-top: 20px;
    padding: 15px;
    border-radius: 5px;
    font-weight: bold;
}

#status-result.online {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

#status-result.offline {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.contact-info {
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.contact-info p {
    margin: 10px 0;
    font-size: 1.1em;
}

.download-section {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 30px;
}

.download-item {
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    text-align: center;
    max-width: 400px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.download-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0,0,0,0.15);
}

.download-item h3 {
    color: #3498db;
    margin-bottom: 15px;
    font-size: 1.3em;
}

.download-item p {
    margin-bottom: 20px;
    color: #666;
}

.download-btn {
    display: inline-block;
    background-color: #3498db;
    color: white;
    padding: 12px 24px;
    border-radius: 5px;
    text-decoration: none;
    font-size: 1em;
    transition: background-color 0.3s ease;
}

.download-btn:hover {
    background-color: #2980b9;
}

footer {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 30px 0;
    margin-top: 60px;
}

footer p {
    opacity: 0.8;
}

@media (max-width: 768px) {
    .container {
        width: 90%;
    }
    
    header h1 {
        font-size: 2em;
    }
    
    nav ul {
        flex-direction: column;
        align-items: center;
    }
    
    nav ul li {
        margin: 5px 0;
    }
    
    .card-system {
        flex-direction: column;
    }
    
    .card-input, .card-info {
        min-width: 100%;
    }
}