/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette */
    --color-primary: #00ADB5;
    --color-secondary: #FFD369;
    --color-dark: #222831;
    --color-medium: #393E46;
    --color-light: #EEEEEE;
    --color-white: #FFFFFF;
    --color-success: #28a745;
    --color-warning: #ffc107;
    --color-danger: #dc3545;
    --color-info: #17a2b8;
    
    /* Typography */
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-dark);
    background-color: var(--color-light);
    overflow-x: hidden;
}

.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Header Styles */
.header {
    background: linear-gradient(135deg, var(--color-dark) 0%, var(--color-medium) 100%);
    color: var(--color-white);
    padding: var(--spacing-xl) 0;
    position: relative;
    overflow: hidden;
}

.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="75" cy="75" r="1" fill="rgba(255,255,255,0.1)"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>');
    opacity: 0.1;
}

.header__content {
    position: relative;
    z-index: 1;
    text-align: center;
}

.header__title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.header__icon {
    font-size: var(--font-size-2xl);
    animation: pulse 2s infinite;
}

.header__subtitle {
    font-size: var(--font-size-lg);
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* Main Content */
.main {
    flex: 1;
    padding: var(--spacing-2xl) 0;
}

/* Card Styles */
.card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    border: 1px solid rgba(0, 173, 181, 0.1);
    transition: var(--transition-normal);
}

.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.card__title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--color-dark);
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    justify-content: space-between;
}

.card__icon {
    font-size: var(--font-size-lg);
}

/* Form Styles */
.form__group {
    margin-bottom: var(--spacing-lg);
}

.form__group--hidden {
    display: none;
}

.form__label {
    display: block;
    font-weight: 500;
    color: var(--color-dark);
    margin-bottom: var(--spacing-sm);
    font-size: var(--font-size-sm);
}

.form__input,
.form__select {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid var(--color-light);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    transition: var(--transition-fast);
    background-color: var(--color-white);
}

.form__input:focus,
.form__select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(0, 173, 181, 0.1);
}

.form__input:invalid {
    border-color: var(--color-danger);
}

.form__help {
    display: block;
    font-size: var(--font-size-xs);
    color: var(--color-medium);
    margin-top: var(--spacing-xs);
}

.form__error {
    display: block;
    font-size: var(--font-size-xs);
    color: var(--color-danger);
    margin-top: var(--spacing-xs);
    min-height: 1rem;
}

.form__checkbox {
    width: auto;
    margin-right: var(--spacing-sm);
}

/* Button Styles */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition-fast);
    position: relative;
    overflow: hidden;
}

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

.btn--primary:hover {
    background-color: #009ca3;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn--secondary {
    background-color: var(--color-secondary);
    color: var(--color-dark);
}

.btn--secondary:hover {
    background-color: #e6be5a;
    transform: translateY(-1px);
}

.btn--small {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
}

.btn--full {
    width: 100%;
}

.btn--toggle {
    justify-content: space-between;
    width: 100%;
}

.btn__icon {
    font-size: var(--font-size-sm);
}

.btn__arrow {
    transition: var(--transition-fast);
}

.btn--toggle.active .btn__arrow {
    transform: rotate(180deg);
}

/* Optional Fields */
.optional-fields {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-normal);
}

.optional-fields.show {
    max-height: 500px;
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--color-light);
}

/* Results Styles */
.results-section,
.comparison-section,
.chart-section {
    display: none;
}

.results-section.show,
.comparison-section.show,
.chart-section.show {
    display: block;
    animation: fadeInUp var(--transition-normal);
}

.results {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.result-item {
    background: linear-gradient(135deg, var(--color-light) 0%, var(--color-white) 100%);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border-left: 4px solid var(--color-primary);
    transition: var(--transition-fast);
}

.result-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.result-item__label {
    font-size: var(--font-size-sm);
    color: var(--color-medium);
    margin-bottom: var(--spacing-xs);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.result-item__value {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--color-dark);
}

.result-item--highlight {
    border-left-color: var(--color-secondary);
    background: linear-gradient(135deg, rgba(255, 211, 105, 0.1) 0%, var(--color-white) 100%);
}

.result-item--negative {
    border-left-color: var(--color-danger);
    background: linear-gradient(135deg, rgba(220, 53, 69, 0.1) 0%, var(--color-white) 100%);
}

/* Comparison Styles */
.comparison {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
}

.comparison-item {
    background: var(--color-white);
    border: 2px solid var(--color-light);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
    transition: var(--transition-fast);
}

.comparison-item:hover {
    border-color: var(--color-primary);
    transform: translateY(-2px);
}

.comparison-item__title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--color-dark);
}

.comparison-item--without-tax {
    border-color: var(--color-success);
}

.comparison-item--with-tax {
    border-color: var(--color-danger);
}

/* Chart Styles */
.chart-container {
    position: relative;
    height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
}

#resultsChart {
    max-width: 100%;
    height: auto;
}

/* History Styles */
.history {
    max-height: 400px;
    overflow-y: auto;
}

.history__empty {
    text-align: center;
    color: var(--color-medium);
    font-style: italic;
    padding: var(--spacing-xl);
}

.history-item {
    background: var(--color-light);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    border-left: 3px solid var(--color-primary);
}

.history-item__header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}

.history-item__date {
    font-size: var(--font-size-sm);
    color: var(--color-medium);
}

.history-item__amount {
    font-weight: 600;
    color: var(--color-primary);
}

.history-item__details {
    font-size: var(--font-size-sm);
    color: var(--color-medium);
}

/* Footer Styles */
.footer {
    background-color: var(--color-dark);
    color: var(--color-light);
    padding: var(--spacing-lg) 0;
    text-align: center;
    margin-top: auto;
}

.footer__text {
    font-size: var(--font-size-sm);
}

.footer__link {
    color: var(--color-primary);
    text-decoration: none;
    transition: var(--transition-fast);
}

.footer__link:hover {
    color: var(--color-secondary);
    text-decoration: underline;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(34, 40, 49, 0.8);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.loading-overlay.show {
    display: flex;
}

.loading-spinner {
    text-align: center;
    color: var(--color-white);
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid rgba(0, 173, 181, 0.3);
    border-top: 4px solid var(--color-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

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

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.1);
    }
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .header__title {
        font-size: var(--font-size-2xl);
        flex-direction: column;
        gap: var(--spacing-xs);
    }
    
    .header__subtitle {
        font-size: var(--font-size-base);
    }
    
    .card {
        padding: var(--spacing-lg);
        margin-bottom: var(--spacing-lg);
    }
    
    .card__title {
        font-size: var(--font-size-lg);
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    .results {
        grid-template-columns: 1fr;
    }
    
    .comparison {
        grid-template-columns: 1fr;
    }
    
    .chart-container {
        height: 300px;
    }
    
    .btn--toggle {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .history-item__header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-xs);
    }
}

@media (max-width: 480px) {
    .main {
        padding: var(--spacing-lg) 0;
    }
    
    .card {
        padding: var(--spacing-md);
        border-radius: var(--radius-md);
    }
    
    .form__input,
    .form__select {
        padding: var(--spacing-sm);
    }
    
    .btn {
        padding: var(--spacing-sm) var(--spacing-md);
    }
    
    .result-item {
        padding: var(--spacing-md);
    }
    
    .result-item__value {
        font-size: var(--font-size-lg);
    }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --color-primary: #0099a3;
        --color-secondary: #cc9900;
        --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
    }
    
    .card {
        border: 2px solid var(--color-medium);
    }
    
    .form__input,
    .form__select {
        border-width: 2px;
    }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .header__icon {
        animation: none;
    }
}

/* Print styles */
@media print {
    .header,
    .footer,
    .btn,
    .optional-fields,
    .loading-overlay {
        display: none !important;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #000;
        break-inside: avoid;
    }
    
    .main {
        padding: 0;
    }
    
    body {
        background: white;
        color: black;
    }
}
#resultsChart {
    width: 100% !important;
    height: auto;
    display: block;
}