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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f7fa;
}

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

header {
    text-align: center;
    margin-bottom: 30px;
    padding: 20px 0;
    background-color: #3498db;
    color: white;
    border-radius: 8px;
    position: relative;
}

h1, h2 {
    margin-bottom: 15px;
}

.join-section {
    text-align: center;
    margin-bottom: 40px;
    padding: 30px;
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.15);
    border: 2px solid #3498db;
}

.join-section h2 {
    font-size: 36px;
    color: #3498db;
    margin-bottom: 30px;
    font-weight: 700;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.1);
}

.join-instructions {
    margin-top: 25px;
    max-width: 400px;
    margin-left: auto;
    margin-right: auto;
    text-align: left;
    background-color: #f8f9fa;
    padding: 15px 25px;
    border-radius: 8px;
}

.join-instructions ol {
    padding-left: 20px;
}

.join-instructions li {
    margin-bottom: 10px;
    font-size: 16px;
    line-height: 1.5;
}

#joinQrCode {
    margin: 40px auto;
    width: 500px;
    height: 500px;
    max-width: 90vw;
    max-height: 90vw;
}

#joinQrCode img {
    width: 100%;
    height: 100%;
    display: block;
}

.form-section {
    margin-bottom: 40px;
    padding: 20px;
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.form-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
}

input, textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

.btn {
    display: inline-block;
    background-color: #3498db;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    transition: background-color 0.3s;
}

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

.participants-section {
    padding: 20px;
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.participants-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.participant-card {
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 15px;
    background-color: #f9f9f9;
    transition: transform 0.3s;
}

.participant-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.participant-name {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 10px;
}

.participant-links {
    margin: 15px 0;
}

.participant-links a {
    display: inline-block;
    margin-right: 10px;
    color: #3498db;
    text-decoration: none;
}

.participant-links a:hover {
    text-decoration: underline;
}

.participant-links a.vcard-download {
    display: block;
    margin-top: 8px;
    padding: 5px 8px;
    background-color: #27ae60;
    color: white;
    border-radius: 4px;
    text-align: center;
}

.participant-links a.vcard-download:hover {
    background-color: #219653;
    text-decoration: none;
}

.participant-qr {
    margin-top: 15px;
    text-align: center;
}

.participant-qr img {
    max-width: 150px;
    margin: 0 auto;
}

@media (max-width: 768px) {
    .participants-grid {
        grid-template-columns: 1fr;
    }
    
    .join-section, .form-section, .participants-section {
        padding: 15px;
    }
}

.sync-status {
    position: absolute;
    top: 10px;
    right: 10px;
    font-size: 14px;
}

.version-info {
    text-align: center;
    padding: 8px 15px;
    color: #666;
    font-size: 0.8em;
    margin-top: 30px;
    border-top: 1px solid #eee;
}

.sync-status.syncing {
    background-color: #fff3cd;
    color: #856404;
}

.sync-status.synced {
    background-color: #d4edda;
    color: #155724;
}

.sync-status.error {
    background-color: #f8d7da;
    color: #721c24;
    padding-right: 10px;
}

.sync-status span {
    margin-right: 5px;
}

.retry-button {
    background-color: #dc3545;
    color: white;
    border: none;
    border-radius: 12px;
    padding: 4px 10px;
    font-size: 12px;
    cursor: pointer;
    margin-left: 5px;
    transition: background-color 0.2s ease;
}

.retry-button:hover {
    background-color: #c82333;
}