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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    text-align: center;
    margin-bottom: 3rem;
    color: white;
}

header h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

header p {
    font-size: 1.2rem;
    font-weight: 300;
    opacity: 0.9;
}

main {
    flex: 1;
    display: grid;
    gap: 2rem;
    grid-template-columns: 1fr;
}

.input-section {
    background: white;
    padding: 2rem;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
}

.input-group {
    margin-bottom: 1.5rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #374151;
}

.input-group input {
    width: 100%;
    padding: 1rem;
    border: 2px solid #e5e7eb;
    border-radius: 12px;
    font-size: 1rem;
    transition: all 0.3s ease;
    background: #f9fafb;
}

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

.options {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.option-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #374151;
}

.option-group select,
.option-group input[type="color"] {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 0.9rem;
    background: #f9fafb;
    transition: all 0.3s ease;
}

.option-group select:focus,
.option-group input[type="color"]:focus {
    outline: none;
    border-color: #667eea;
    background: white;
}

.option-group input[type="color"] {
    height: 3rem;
    cursor: pointer;
}

.generate-btn {
    width: 100%;
    padding: 1rem 2rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.generate-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

.generate-btn:active {
    transform: translateY(0);
}

.demo-btn {
    width: 100%;
    padding: 0.75rem 1.5rem;
    background: transparent;
    color: #667eea;
    border: 2px solid #667eea;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 1rem;
}

.demo-btn:hover {
    background: #667eea;
    color: white;
    transform: translateY(-1px);
}

.result-section {
    background: white;
    padding: 2rem;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    text-align: center;
    display: none;
    animation: fadeInUp 0.5s ease;
}

.result-section.show {
    display: block;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.qr-container {
    margin-bottom: 2rem;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 200px;
}

.qr-code-wrapper {
    text-align: center;
}

#qr-code {
    padding: 1rem;
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    border: 2px solid #f3f4f6;
    transition: all 0.3s ease;
    display: inline-block;
}

#qr-code:hover {
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
    transform: translateY(-2px);
}

#qr-code canvas {
    display: block;
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}

.qr-code-label {
    display: block;
    margin-bottom: 1rem;
    font-size: 1.1rem;
    font-weight: 600;
    color: #374151;
}

.qr-loading {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 200px;
    font-size: 1rem;
    color: #6b7280;
    font-weight: 500;
}

.qr-loading::after {
    content: '';
    width: 20px;
    height: 20px;
    border: 2px solid #e5e7eb;
    border-top: 2px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-left: 0.5rem;
}

.actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 1rem;
}

.action-btn {
    padding: 0.75rem 1.5rem;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    background: white;
    color: #374151;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.action-btn:hover {
    border-color: #667eea;
    color: #667eea;
    transform: translateY(-1px);
}

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

.copy-btn:hover {
    background: #10b981;
    color: white;
    border-color: #10b981;
}

.url-display {
    padding: 1rem;
    background: #f3f4f6;
    border-radius: 8px;
    font-size: 0.9rem;
    color: #6b7280;
    word-break: break-all;
}

.url-display span:first-child {
    font-weight: 500;
}

.url-display span:last-child {
    color: #374151;
    font-weight: 600;
}

footer {
    text-align: center;
    margin-top: 2rem;
    color: white;
    opacity: 0.8;
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .input-section,
    .result-section {
        padding: 1.5rem;
    }
    
    .options {
        grid-template-columns: 1fr;
    }
    
    .actions {
        flex-direction: column;
        align-items: center;
    }
    
    .action-btn {
        width: 100%;
        max-width: 200px;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    header h1 {
        font-size: 1.8rem;
    }
    
    header p {
        font-size: 1rem;
    }
    
    .input-section,
    .result-section {
        padding: 1rem;
    }
}

/* Loading state */
.generate-btn.loading {
    opacity: 0.7;
    cursor: not-allowed;
    pointer-events: none;
}

.generate-btn.loading::after {
    content: '';
    width: 20px;
    height: 20px;
    border: 2px solid transparent;
    border-top: 2px solid white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-left: 0.5rem;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Success animations */
.copy-btn.success {
    background: #10b981 !important;
    color: white !important;
    border-color: #10b981 !important;
}

.copy-btn.success::after {
    content: ' ✓';
}