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

:root {
    /* Color Palette */
    --color-primary: #F8B195;
    --color-secondary: #F67280;
    --color-accent: #C06C84;
    --color-dark: #6C5B7B;
    --color-darker: #355C7D;
    
    /* Light Theme */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-card: #ffffff;
    --text-primary: #2c3e50;
    --text-secondary: #6c757d;
    --border-color: #e9ecef;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 20px rgba(0, 0, 0, 0.15);
    
    /* Typography */
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-size-base: 16px;
    --font-size-sm: 14px;
    --font-size-lg: 18px;
    --font-size-xl: 24px;
    --font-size-xxl: 32px;
    --line-height: 1.6;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-xxl: 3rem;
    
    /* Border Radius */
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* Dark Theme */
[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --bg-card: #2d2d2d;
    --text-primary: #ffffff;
    --text-secondary: #b0b0b0;
    --border-color: #404040;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 4px 20px rgba(0, 0, 0, 0.4);
}

/* Base Styles */
html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    line-height: var(--line-height);
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: background-color var(--transition-normal), color var(--transition-normal);
    overflow-x: hidden;
}

/* Container */
.container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Header */
.header {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
    padding: var(--spacing-xl) 0;
    margin-bottom: var(--spacing-xl);
    border-radius: 0 0 var(--border-radius-lg) var(--border-radius-lg);
    box-shadow: var(--shadow);
}

.header__content {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    position: relative;
}

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

.header__subtitle {
    font-size: var(--font-size-lg);
    opacity: 0.9;
    margin-bottom: var(--spacing-md);
}

.header__controls {
    position: absolute;
    top: 0;
    right: 0;
}

/* Theme Toggle */
.theme-toggle {
    background: rgba(255, 255, 255, 0.2);
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    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-lg);
    transition: transform var(--transition-normal);
}

.theme-toggle:hover .theme-toggle__icon {
    transform: rotate(180deg);
}

/* Main Content */
.main {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

/* Cards */
.card {
    background: var(--bg-card);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    transition: all var(--transition-normal);
}

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

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

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

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

/* Form Styles */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.form-label {
    font-weight: 600;
    color: var(--text-primary);
    font-size: var(--font-size-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-label--secondary {
   
    color: var(--text-secondary);
    font-size: var(--font-size-xs);
    margin-top: -var(--spacing-xs);
    margin-bottom: var(--spacing-md);
  
}

.form-input {
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-md);
    font-size: var(--font-size-base);
    background: var(--bg-secondary);
    color: var(--text-primary);
    transition: all var(--transition-normal);
    outline: none;
}

.form-input:focus {
    border-color: var(--color-primary);
    background: var(--bg-card);
    box-shadow: 0 0 0 3px rgba(248, 177, 149, 0.1);
}

.form-input:invalid {
    border-color: var(--color-secondary);
}

/* Buttons */
.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(--border-radius-md);
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-decoration: none;
    outline: none;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left var(--transition-slow);
}

.btn:hover::before {
    left: 100%;
}

.btn--primary {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
    box-shadow: 0 4px 15px rgba(248, 177, 149, 0.3);
}

.btn--primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(248, 177, 149, 0.4);
}

.btn--secondary {
    background: var(--color-accent);
    color: white;
    box-shadow: 0 4px 15px rgba(192, 108, 132, 0.3);
}

.btn--secondary:hover {
    background: var(--color-dark);
    transform: translateY(-2px);
}

.btn--danger {
    background: var(--color-secondary);
    color: white;
    box-shadow: 0 4px 15px rgba(246, 114, 128, 0.3);
}

.btn--danger:hover {
    background: #e55a6b;
    transform: translateY(-2px);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

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

/* Results Grid */
.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
}

.result-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: var(--spacing-lg);
    background: var(--bg-secondary);
    border-radius: var(--border-radius-md);
    border: 2px solid transparent;
    transition: all var(--transition-normal);
}

.result-item:hover {
    border-color: var(--color-primary);
    transform: scale(1.02);
}

.result-item__label {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

.result-item__value {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-darker);
}

/* Simulator */
.simulator {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.simulator .form-group {
    flex-direction: row;
    align-items: flex-end;
    gap: var(--spacing-md);
}

.simulator .form-group .form-input {
    flex: 1;
}

.simulator-results {
    padding: var(--spacing-lg);
    background: var(--bg-secondary);
    border-radius: var(--border-radius-md);
    text-align: center;
}

.profit-loss {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
}

.profit-loss__label {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

.profit-loss__value {
    font-size: var(--font-size-xxl);
    font-weight: 700;
}

.profit-loss__percentage {
    font-size: var(--font-size-lg);
    font-weight: 600;
}

.profit-loss--positive .profit-loss__value,
.profit-loss--positive .profit-loss__percentage {
    color: #28a745;
}

.profit-loss--negative .profit-loss__value,
.profit-loss--negative .profit-loss__percentage {
    color: #dc3545;
}

/* Table */
.table-container {
    overflow-x: auto;
    border-radius: var(--border-radius-md);
    border: 1px solid var(--border-color);
}

.purchases-table {
    width: 100%;
    border-collapse: collapse;
    font-size: var(--font-size-sm);
}

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

.purchases-table th {
    background: var(--bg-secondary);
    font-weight: 600;
    color: var(--text-primary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    position: sticky;
    top: 0;
    z-index: 1;
}

.purchases-table tbody tr {
    transition: background-color var(--transition-fast);
}

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

.empty-state td {
    text-align: center;
    color: var(--text-secondary);
    font-style: italic;
    padding: var(--spacing-xxl);
}

.delete-btn {
    background: var(--color-secondary);
    color: white;
    border: none;
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-xs) var(--spacing-sm);
    cursor: pointer;
    font-size: 12px;
    transition: all var(--transition-fast);
}

.delete-btn:hover {
    background: #e55a6b;
    transform: scale(1.1);
}

/* FAQ */
.faq {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.faq-item {
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-md);
    overflow: hidden;
    transition: all var(--transition-normal);
}

.faq-item:hover {
    border-color: var(--color-primary);
}

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

.faq-question:hover {
    background: var(--color-primary);
    color: white;
}

.faq-icon {
    font-size: var(--font-size-lg);
    font-weight: 300;
    transition: transform var(--transition-normal);
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 var(--spacing-lg);
    background: var(--bg-card);
    max-height: 0;
    overflow: hidden;
    transition: all var(--transition-normal);
}

.faq-item.active .faq-answer {
    padding: var(--spacing-lg);
    max-height: 200px;
}

.faq-answer p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* Footer */
.footer {
    margin-top: var(--spacing-xxl);
    padding: var(--spacing-xl) 0;
    border-top: 1px solid var(--border-color);
    background: var(--bg-secondary);
}

.footer__content {
    text-align: center;
}

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

.footer__link {
    color: var(--color-accent);
    text-decoration: none;
    font-weight: 600;
    transition: color var(--transition-fast);
}

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

/* Toast Notification */
.toast {
    position: fixed;
    bottom: var(--spacing-lg);
    right: var(--spacing-lg);
    background: var(--color-darker);
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-hover);
    transform: translateX(100%);
    transition: transform var(--transition-normal);
    z-index: 1000;
    max-width: 300px;
}

.toast.show {
    transform: translateX(0);
}

.toast--success {
    background: #28a745;
}

.toast--error {
    background: #dc3545;
}

.toast--warning {
    background: #ffc107;
    color: #000;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .header {
        padding: var(--spacing-lg) 0;
        margin-bottom: var(--spacing-lg);
    }
    
    .header__title {
        font-size: var(--font-size-xl);
    }
    
    .header__subtitle {
        font-size: var(--font-size-base);
    }
    
    .header__controls {
        position: static;
        margin-top: var(--spacing-md);
    }
    
    .card {
        padding: var(--spacing-lg);
    }
    
    .card__header {
        flex-direction: column;
        align-items: stretch;
    }
    
    .card__actions {
        justify-content: center;
    }
    
    .form-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .results-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }
    
    .simulator .form-group {
        flex-direction: column;
        align-items: stretch;
    }
    
    .btn {
        padding: var(--spacing-md);
        font-size: var(--font-size-sm);
    }
    
    .toast {
        bottom: var(--spacing-sm);
        right: var(--spacing-sm);
        left: var(--spacing-sm);
        max-width: none;
    }
    
    .purchases-table {
        font-size: 12px;
    }
    
    .purchases-table th,
    .purchases-table td {
        padding: var(--spacing-sm);
    }
}

@media (max-width: 480px) {
    .results-grid {
        grid-template-columns: 1fr;
    }
    
    .result-item__value {
        font-size: var(--font-size-lg);
    }
    
    .profit-loss__value {
        font-size: var(--font-size-xl);
    }
}

/* Animation Classes */
.fade-in {
    animation: fadeIn 0.5s ease-in;
}

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

.slide-in {
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        transform: translateX(-100%);
    }
    to {
        transform: translateX(0);
    }
}

/* Loading States */
.loading {
    position: relative;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin: -10px 0 0 -10px;
    border: 2px solid transparent;
    border-top: 2px solid var(--color-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

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

/* Focus styles for keyboard navigation */
.btn:focus,
.form-input:focus,
.theme-toggle:focus,
.faq-question:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
        --shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
    }
    
    [data-theme="dark"] {
        --border-color: #ffffff;
        --text-secondary: #ffffff;
    }
}

/* Print styles */
@media print {
    .header__controls,
    .card__actions,
    .btn,
    .toast {
        display: none !important;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #000;
        break-inside: avoid;
    }
    
    .container {
        max-width: none;
        padding: 0;
    }
}