:root {
    --primary: #6750A4;
    --on-primary: #FFFFFF;
    --primary-container: #EADDFF;
    --on-primary-container: #21005D;
    --surface: #FFFFFF;
    --on-surface: #1C1B1F;
    --surface-variant: #E7E0EC;
    --on-surface-variant: #49454F;
    --outline: #79747E;
    --success: #4CAF50;
    --error: #F44336;
    --warning: #FFB300;
    --background: #FAFAFA;
    --spacing-xs: 8px; 
    --spacing-sm: 12px; 
    --spacing-md: 16px; 
    --spacing-lg: 24px; 
    --spacing-xl: 32px;
    --radius-sm: 8px; 
    --radius-md: 12px; 
    --radius-lg: 20px;
    --font-family: 'Inter', sans-serif;
}

@media (prefers-color-scheme: dark) {
    :root {
        --primary: #D0BCFF;
        --on-primary: #381E72;
        --primary-container: #4F378B;
        --on-primary-container: #EADDFF;
        --surface: #1C1B1F;
        --on-surface: #E6E1E5;
        --surface-variant: #49454F;
        --on-surface-variant: #CAC4D0;
        --outline: #938F99;
        --background: #121115;
    }
}

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

body {
    font-family: var(--font-family);
    background: var(--background);
    color: var(--on-surface);
    line-height: 1.6;
    min-height: 100vh;
    padding-bottom: 80px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-md);
}

.app-header {
    text-align: center;
    padding: var(--spacing-xl) 0 var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.app-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-md);
    background: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--on-primary);
    font-size: 36px;
}

.app-title {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.app-subtitle {
    font-size: 16px;
    color: var(--on-surface-variant);
    font-weight: 400;
}

.main-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    margin-bottom: var(--spacing-lg);
    border: 1px solid var(--outline);
}

.input-section {
    margin-bottom: var(--spacing-lg);
}

.input-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-size: 14px;
    font-weight: 500;
    color: var(--primary);
}

.text-input {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid var(--surface-variant);
    border-radius: var(--radius-md);
    font-size: 18px;
    font-family: monospace;
    background: var(--surface);
    color: var(--on-surface);
    transition: all 0.2s;
}

.text-input:focus {
    outline: none;
    border-color: var(--primary);
}

.text-input::placeholder {
    color: var(--on-surface-variant);
    opacity: 0.7;
}

.action-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
}

.btn {
    padding: var(--spacing-md);
    border: none;
    border-radius: var(--radius-md);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    transition: all 0.2s;
}

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

.btn-primary:hover {
    opacity: 0.9;
}

.btn-secondary {
    background: var(--surface-variant);
    color: var(--on-surface-variant);
}

.btn-secondary:hover {
    background: color-mix(in srgb, var(--surface-variant) 90%, var(--on-surface-variant));
}

.result-card {
    background: var(--primary-container);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    margin-top: var(--spacing-lg);
    display: none;
}

.result-card.visible {
    display: block;
}

.result-status {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--on-primary-container);
}

.result-document {
    font-size: 28px;
    font-weight: 700;
    font-family: monospace;
    margin-bottom: var(--spacing-lg);
    color: var(--on-primary-container);
    word-break: break-all;
}

.result-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.btn-outline {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 2px solid var(--outline);
    background: transparent;
    color: var(--on-primary-container);
    border-radius: var(--radius-md);
    font-weight: 500;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all 0.2s;
}

.btn-outline:hover {
    background: rgba(255,255,255,0.1);
    border-color: var(--on-primary-container);
}

.utility-buttons {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-sm);
    margin: var(--spacing-lg) 0;
}

.btn-utility {
    padding: var(--spacing-md);
    border: 1px solid var(--outline);
    background: var(--surface);
    color: var(--on-surface);
    border-radius: var(--radius-md);
    font-weight: 500;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all 0.2s;
}

.btn-utility:hover {
    background: var(--surface-variant);
}

.btn-utility i {
    font-size: 20px;
    color: var(--primary);
}

.footer {
    text-align: center;
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--surface-variant);
    color: var(--on-surface-variant);
    font-size: 14px;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-md);
}

.footer-link {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
}

.footer-link:hover {
    text-decoration: underline;
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    max-width: 500px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
}

.modal-title {
    font-size: 20px;
    font-weight: 600;
    color: var(--on-surface);
}

.modal-close {
    background: none;
    border: none;
    color: var(--on-surface-variant);
    cursor: pointer;
    font-size: 24px;
    line-height: 1;
}

.modal-section {
    margin-bottom: var(--spacing-lg);
}

.modal-section h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--on-surface);
}

.modal-section p {
    color: var(--on-surface-variant);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.toast {
    position: fixed;
    bottom: var(--spacing-lg);
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--on-surface);
    color: var(--surface);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 1001;
    max-width: 90%;
    text-align: center;
    font-weight: 500;
}

.toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

@media (max-width: 600px) {
    .container {
        padding: var(--spacing-sm);
    }
    
    .utility-buttons {
        grid-template-columns: 1fr;
    }
    
    .action-buttons {
        grid-template-columns: 1fr;
    }
    
    .result-actions {
        flex-direction: column;
    }
    
    .result-document {
        font-size: 22px;
    }
    
    .btn {
        padding: var(--spacing-sm);
    }
}

.status-valid {
    color: var(--success);
}

.status-invalid {
    color: var(--error);
}

.status-generated {
    color: var(--warning);
}