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

:root {
    /* Color Palette */
    --color-primary: #F6DFEB;
    --color-secondary: #E4C1F9;
    --color-accent: #D0F4DE;
    --color-highlight: #FCF6BD;
    --color-tertiary: #FFB7C5;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    --gradient-secondary: linear-gradient(135deg, var(--color-accent), var(--color-highlight));
    --gradient-tertiary: linear-gradient(135deg, var(--color-secondary), var(--color-tertiary));
    --gradient-card: linear-gradient(145deg, rgba(246, 223, 235, 0.8), rgba(228, 193, 249, 0.6));
    
    /* Light Theme Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --text-primary: #2d3748;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --border-color: #e2e8f0;
    --shadow-light: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 16px rgba(0, 0, 0, 0.15);
    --shadow-heavy: 0 8px 32px rgba(0, 0, 0, 0.2);
    
    /* 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;
    --font-size-4xl: 2.25rem;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    
    /* Transitions */
    --transition-fast: 0.15s ease-in-out;
    --transition-base: 0.3s ease-in-out;
    --transition-slow: 0.5s ease-in-out;
}

/* Dark Theme */
[data-theme="dark"] {
    --bg-primary: #1a202c;
    --bg-secondary: #2d3748;
    --text-primary: #f7fafc;
    --text-secondary: #e2e8f0;
    --text-muted: #a0aec0;
    --border-color: #4a5568;
    --shadow-light: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-medium: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-heavy: 0 8px 32px rgba(0, 0, 0, 0.5);
}

/* Base Styles */
html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-primary);
    transition: background-color var(--transition-base), color var(--transition-base);
}

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

/* Header Styles */
.header {
    background: var(--gradient-primary);
    padding: var(--spacing-xl) var(--spacing-md);
    text-align: center;
    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="50" cy="50" r="1" fill="rgba(255,255,255,0.1)"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>');
    opacity: 0.3;
}

.header__content {
    position: relative;
    z-index: 1;
    max-width: 1200px;
    margin: 0 auto;
}

.header__title {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.header__subtitle {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

/* Theme Toggle */
.theme-toggle {
    position: absolute;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    background: rgba(255, 255, 255, 0.2);
    border: none;
    border-radius: 50%;
    width: 3rem;
    height: 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-base);
    backdrop-filter: blur(10px);
}

.theme-toggle:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.1);
}

.theme-toggle__icon {
    font-size: var(--font-size-xl);
}

/* Main Content */
.main {
    flex: 1;
    padding: var(--spacing-2xl) var(--spacing-md);
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

/* Form Styles */
.investment-form {
    margin-bottom: var(--spacing-3xl);
}

.form-container {
    background: var(--gradient-card);
    border-radius: var(--radius-2xl);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-medium);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.form-container__title {
    font-size: var(--font-size-2xl);
    font-weight: 600;
    margin-bottom: var(--spacing-xl);
    color: var(--text-primary);
    text-align: center;
}

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

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

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

.form-group__label {
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

.form-group__input,
.form-group__select {
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-base);
    background: var(--bg-primary);
    color: var(--text-primary);
    transition: all var(--transition-base);
}

.form-group__input:focus,
.form-group__select:focus {
    outline: none;
    border-color: var(--color-secondary);
    box-shadow: 0 0 0 3px rgba(228, 193, 249, 0.2);
}

.form-group__input::placeholder {
    color: var(--text-muted);
}

/* Checkbox Styles */
.checkbox-group {
    display: flex;
    align-items: center;
    cursor: pointer;
    user-select: none;
}

.checkbox-group__input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
}

.checkbox-group__checkmark {
    width: 1.25rem;
    height: 1.25rem;
    background: var(--bg-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    margin-right: var(--spacing-md);
    position: relative;
    transition: all var(--transition-base);
}

.checkbox-group__input:checked + .checkbox-group__checkmark {
    background: var(--gradient-secondary);
    border-color: var(--color-accent);
}

.checkbox-group__input:checked + .checkbox-group__checkmark::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: var(--text-primary);
    font-weight: bold;
    font-size: var(--font-size-sm);
}

.checkbox-group__label {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
}

/* Button Styles */
.btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-lg);
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    text-decoration: none;
    min-height: 3rem;
}

.btn--primary {
    background: var(--gradient-tertiary);
    color: var(--text-primary);
    box-shadow: var(--shadow-light);
}

.btn--primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

.btn--secondary {
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border: 2px solid var(--border-color);
}

.btn--secondary:hover {
    background: var(--bg-primary);
    border-color: var(--color-secondary);
}

.btn--danger {
    background: linear-gradient(135deg, #ff6b6b, #ee5a52);
    color: white;
}

.btn--danger:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

.btn--small {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    min-height: 2rem;
}

/* Investment Cards */
.investments-list {
    margin-bottom: var(--spacing-3xl);
}

.investments-container__title {
    font-size: var(--font-size-2xl);
    font-weight: 600;
    margin-bottom: var(--spacing-xl);
    color: var(--text-primary);
    text-align: center;
}

.investments-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.investment-card {
    background: var(--gradient-card);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-light);
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.investment-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-tertiary);
}

.investment-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-medium);
}

.investment-card__header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--spacing-lg);
}

.investment-card__title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.investment-card__type {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    background: rgba(255, 255, 255, 0.3);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
}

.investment-card__details {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.investment-card__detail {
    text-align: center;
}

.investment-card__detail-label {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: var(--spacing-xs);
}

.investment-card__detail-value {
    font-size: var(--font-size-base);
    font-weight: 600;
    color: var(--text-primary);
}

.investment-card__actions {
    display: flex;
    gap: var(--spacing-sm);
}

/* Results Section */
.results {
    margin-bottom: var(--spacing-3xl);
}

.results-container__title {
    font-size: var(--font-size-2xl);
    font-weight: 600;
    margin-bottom: var(--spacing-xl);
    color: var(--text-primary);
    text-align: center;
}

/* Summary Cards */
.summary-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
}

.summary-card {
    background: var(--gradient-card);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    text-align: center;
    box-shadow: var(--shadow-light);
    border: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    overflow: hidden;
}

.summary-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-secondary);
}

.summary-card--best::before {
    background: var(--gradient-tertiary);
}

.summary-card__icon {
    font-size: var(--font-size-3xl);
    margin-bottom: var(--spacing-md);
}

.summary-card__title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.summary-card__value {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.summary-card__subtitle {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
}

.summary-card__badge {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background: var(--gradient-tertiary);
    color: var(--text-primary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
}

/* Chart Container */
.chart-container {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
    box-shadow: var(--shadow-light);
    border: 1px solid var(--border-color);
}

.chart-canvas {
    width: 100%;
    height: 400px;
}

/* Results Table */
.results-table-container {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-light);
    border: 1px solid var(--border-color);
}

.results-table {
    width: 100%;
    border-collapse: collapse;
}

.results-table th,
.results-table td {
    padding: var(--spacing-md);
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.results-table th {
    background: var(--gradient-secondary);
    font-weight: 600;
    color: var(--text-primary);
    font-size: var(--font-size-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.results-table td {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
}

.results-table tr:hover {
    background: var(--bg-secondary);
}

.results-table__best {
    background: rgba(208, 244, 222, 0.3);
}

/* FAQ Section */
.faq {
    margin-bottom: var(--spacing-3xl);
}

.faq-container__title {
    font-size: var(--font-size-2xl);
    font-weight: 600;
    margin-bottom: var(--spacing-xl);
    color: var(--text-primary);
    text-align: center;
}

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

.faq-item {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-md);
    box-shadow: var(--shadow-light);
    border: 1px solid var(--border-color);
    overflow: hidden;
}

.faq-item__question {
    width: 100%;
    padding: var(--spacing-lg);
    background: none;
    border: none;
    text-align: left;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: var(--font-size-base);
    font-weight: 600;
    color: var(--text-primary);
    transition: background-color var(--transition-base);
}

.faq-item__question:hover {
    background: var(--bg-secondary);
}

.faq-item__question[aria-expanded="true"] .faq-item__icon {
    transform: rotate(45deg);
}

.faq-item__icon {
    font-size: var(--font-size-xl);
    transition: transform var(--transition-base);
}

.faq-item__answer {
    padding: 0 var(--spacing-lg) var(--spacing-lg);
    color: var(--text-secondary);
    line-height: 1.6;
    display: none;
}

.faq-item__answer.active {
    display: block;
    animation: fadeInDown 0.3s ease-out;
}

/* Footer */
.footer {
    background: var(--gradient-primary);
    padding: var(--spacing-lg);
    text-align: center;
    margin-top: auto;
}

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

.footer__text a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 600;
}

.footer__text a:hover {
    text-decoration: underline;
}

/* Utility Classes */
.hidden {
    display: none !important;
}

.text-center {
    text-align: center;
}

.text-right {
    text-align: right;
}

.mt-auto {
    margin-top: auto;
}

/* Loading Spinner */
.loading-spinner {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.spinner {
    width: 3rem;
    height: 3rem;
    border: 4px solid var(--color-primary);
    border-top: 4px solid var(--color-secondary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.toast {
    background: var(--gradient-card);
    color: var(--text-primary);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-medium);
    border: 1px solid rgba(255, 255, 255, 0.2);
    min-width: 300px;
    animation: slideInRight 0.3s ease-out;
}

.toast--success {
    background: linear-gradient(135deg, var(--color-accent), #a8e6cf);
}

.toast--error {
    background: linear-gradient(135deg, #ff6b6b, #ee5a52);
    color: white;
}

.toast--warning {
    background: linear-gradient(135deg, var(--color-highlight), #ffd93d);
}

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

@keyframes slideInRight {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

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

/* Responsive Design */
@media (max-width: 768px) {
    :root {
        --font-size-4xl: 1.875rem;
        --font-size-3xl: 1.5rem;
        --font-size-2xl: 1.25rem;
    }
    
    .main {
        padding: var(--spacing-lg) var(--spacing-sm);
    }
    
    .form-container,
    .investment-card {
        padding: var(--spacing-lg);
    }
    
    .form-grid {
        grid-template-columns: 1fr;
    }
    
    .theme-toggle {
        top: var(--spacing-md);
        right: var(--spacing-md);
        width: 2.5rem;
        height: 2.5rem;
    }
    
    .header {
        padding: var(--spacing-lg) var(--spacing-sm);
    }
    
    .investment-card__details {
        grid-template-columns: 1fr;
    }
    
    .investment-card__actions {
        flex-direction: column;
    }
    
    .summary-cards {
        grid-template-columns: 1fr;
    }
    
    .results-table-container {
        overflow-x: auto;
    }
    
    .results-table {
        min-width: 600px;
    }
    
    .toast-container {
        left: var(--spacing-sm);
        right: var(--spacing-sm);
    }
    
    .toast {
        min-width: auto;
    }
}

@media (max-width: 480px) {
    .header__title {
        font-size: var(--font-size-2xl);
    }
    
    .header__subtitle {
        font-size: var(--font-size-base);
    }
    
    .investments-grid {
        grid-template-columns: 1fr;
    }
    
    .chart-canvas {
        height: 300px;
    }
}

/* Print Styles */
@media print {
    .theme-toggle,
    .investment-form,
    .faq {
        display: none;
    }
    
    .main {
        padding: 0;
    }
    
    .investment-card,
    .summary-card,
    .results-table-container {
        box-shadow: none;
        border: 1px solid #ccc;
    }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000;
        --shadow-light: 0 2px 8px rgba(0, 0, 0, 0.3);
        --shadow-medium: 0 4px 16px rgba(0, 0, 0, 0.4);
    }
    
    .form-group__input,
    .form-group__select {
        border-width: 3px;
    }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}