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

:root {
    --primary-color: #0066cc;
    --secondary-color: #f5f5f5;
    --text-color: #333;
    --text-light: #666;
    --border-color: #ddd;
    --success-color: #28a745;
    --danger-color: #dc3545;
}

html, body {
    height: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    color: var(--text-color);
    line-height: 1.6;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 600px;
}

.content {
    background: white;
    border-radius: 12px;
    padding: 40px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 40px;
    font-size: 28px;
}

.qrcode-display {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 300px;
    margin-bottom: 30px;
/*    background-color: var(--secondary-color);*/
    border-radius: 8px;
/*    border: 2px dashed var(--border-color);*/
}

.qrcode-display img {
    max-width: 100%;
    max-height: 300px;
    object-fit: contain;
    border-radius: 4px;
}

.loading {
    color: var(--text-light);
    font-size: 16px;
}

.button-group {
    display: flex;
    gap: 10px;
    justify-content: center;
    margin-bottom: 20px;
}

.btn {
    padding: 12px 30px;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
    display: inline-block;
    text-align: center;
    min-width: 120px;
}

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

.btn-primary:hover:not(:disabled) {
    background-color: #0052a3;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background-color: #e8e8e8;
    transform: translateY(-2px);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.message {
    padding: 12px 16px;
    border-radius: 6px;
    text-align: center;
    display: none;
    font-size: 14px;
    animation: slideIn 0.3s ease-out;
}

.message.show {
    display: block;
}

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

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

.message.info {
    background-color: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .content {
        padding: 30px 20px;
    }
    
    h1 {
        font-size: 24px;
        margin-bottom: 30px;
    }
    
    .qrcode-display {
        min-height: 250px;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .content {
        padding: 20px;
        border-radius: 8px;
    }
    
    h1 {
        font-size: 20px;
        margin-bottom: 20px;
    }
    
    .qrcode-display {
        min-height: 200px;
        margin-bottom: 20px;
    }
    
    .btn {
        padding: 10px 20px;
        font-size: 14px;
    }
}