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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 800px;
    margin: 0 auto;
}

.header {
    text-align: center;
    color: white;
    margin-bottom: 30px;
}

.header h1 {
    font-size: 2rem;
    margin-bottom: 8px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

.subtitle {
    font-size: 1rem;
    opacity: 0.95;
}

.demo-card {
    background: white;
    border-radius: 16px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
    padding: 20px;
    margin-bottom: 15px;
}

.card-header {
    text-align: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 2px solid #f0f0f0;
}

.card-header h2 {
    color: #667eea;
    margin-bottom: 5px;
    font-size: 1.3rem;
}

.card-header p {
    color: #666;
    font-size: 0.9rem;
}

.checkout-form {
    position: relative;
}

.form-section {
    display: none;
}

.form-section.active {
    display: block;
    animation: fadeIn 0.3s ease-in;
}

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

.section-title {
    color: #333;
    margin-bottom: 20px;
    font-size: 1.3rem;
}

.form-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 20px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group.full-width {
    grid-column: 1 / -1;
}

.form-group label {
    font-weight: 500;
    margin-bottom: 8px;
    color: #555;
    font-size: 0.9rem;
}

.form-group input,
.form-group select {
    padding: 12px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.payment-methods {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
}

.payment-option {
    flex: 1;
    display: flex;
    align-items: center;
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.payment-option:hover {
    border-color: #667eea;
    background: #f8f9ff;
}

.payment-option input[type="radio"] {
    margin-right: 10px;
}

.order-summary {
    background: #f8f9ff;
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 20px;
}

.summary-item {
    display: flex;
    justify-content: space-between;
    padding: 10px 0;
    border-bottom: 1px solid #e0e0e0;
}

.summary-item.total {
    border-bottom: none;
    font-size: 1.2rem;
    font-weight: bold;
    color: #667eea;
    padding-top: 15px;
    margin-top: 10px;
    border-top: 2px solid #667eea;
}

.checkbox-label {
    display: flex;
    align-items: center;
    cursor: pointer;
}

.checkbox-label input {
    margin-right: 10px;
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.button-group {
    display: flex;
    gap: 10px;
    margin-top: 20px;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    flex: 1;
}

.btn-primary {
    background: #667eea;
    color: white;
}

.btn-primary:hover {
    background: #5568d3;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: #e0e0e0;
    color: #333;
}

.btn-secondary:hover {
    background: #d0d0d0;
}

.btn-success {
    background: #10b981;
    color: white;
}

.btn-success:hover {
    background: #059669;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.4);
}

.info-card {
    background: white;
    border-radius: 16px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
    padding: 20px;
}

.info-card h3 {
    color: #667eea;
    margin-bottom: 12px;
    font-size: 1.1rem;
}

.info-card ul {
    list-style: none;
    margin-bottom: 12px;
}

.info-card li {
    padding: 6px 0;
    padding-left: 20px;
    position: relative;
    font-size: 0.9rem;
}

.info-card li:before {
    content: "→";
    position: absolute;
    left: 0;
    color: #667eea;
    font-weight: bold;
}

.tech-note {
    background: #f8f9ff;
    padding: 15px;
    border-radius: 8px;
    border-left: 4px solid #667eea;
    margin-top: 15px;
    font-weight: 500;
}

/* Demo Controls */
.demo-controls {
    position: fixed;
    bottom: 15px;
    right: 15px;
    background: white;
    border-radius: 8px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.2);
    padding: 8px;
    z-index: 9999;
    border: 2px solid #667eea;
}

.demo-buttons {
    display: flex;
    gap: 6px;
}

.btn-demo {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    color: white;
}

.btn-play {
    background: #10b981;
}

.btn-play:hover {
    background: #059669;
    transform: scale(1.05);
}

.btn-pause {
    background: #f59e0b;
}

.btn-pause:hover {
    background: #d97706;
    transform: scale(1.05);
}

.btn-stop {
    background: #ef4444;
}

.btn-stop:hover {
    background: #dc2626;
    transform: scale(1.05);
}

.btn-demo.hidden {
    display: none;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.toast {
    background: white;
    padding: 16px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 300px;
    animation: slideIn 0.3s ease;
    border-left: 4px solid #667eea;
}

.toast.success {
    border-left-color: #10b981;
}

.toast.error {
    border-left-color: #ef4444;
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10001;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: white;
    padding: 40px;
    border-radius: 16px;
    text-align: center;
    max-width: 400px;
    animation: scaleIn 0.3s ease;
}

@keyframes scaleIn {
    from {
        transform: scale(0.8);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

.success-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.modal-content h2 {
    color: #667eea;
    margin-bottom: 15px;
}

.modal-content p {
    color: #666;
    margin-bottom: 25px;
}

/* Responsive */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }
    
    .header {
        margin-bottom: 15px;
    }
    
    .header h1 {
        font-size: 1.5rem;
    }
    
    .subtitle {
        font-size: 0.9rem;
    }
    
    .demo-card {
        padding: 15px;
    }
    
    .card-header h2 {
        font-size: 1.1rem;
    }
    
    .form-grid {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        font-size: 1.1rem;
    }
    
    .demo-controls {
        bottom: 10px;
        right: 10px;
        padding: 6px;
    }
    
    .btn-demo {
        width: 32px;
        height: 32px;
        font-size: 0.9rem;
    }
    
    .toast-container {
        right: 10px;
        left: 10px;
    }
    
    .toast {
        min-width: auto;
        font-size: 0.9rem;
        padding: 12px 16px;
    }
}