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

:root {
    /* Color Palette */
    --color-primary: #355C7D;
    --color-secondary: #6C5B7B;
    --color-tertiary: #C06C84;
    --color-quaternary: #F67280;
    --color-quinary: #F8B195;
    
    /* Gradient Definitions */
    --gradient-primary: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    --gradient-secondary: linear-gradient(135deg, var(--color-secondary) 0%, var(--color-tertiary) 100%);
    --gradient-tertiary: linear-gradient(135deg, var(--color-tertiary) 0%, var(--color-quaternary) 100%);
    --gradient-quaternary: linear-gradient(135deg, var(--color-quaternary) 0%, var(--color-quinary) 100%);
    --gradient-success: linear-gradient(135deg, #28a745 0%, #20c997 100%);
    --gradient-warning: linear-gradient(135deg, #ffc107 0%, #fd7e14 100%);
    --gradient-info: linear-gradient(135deg, #17a2b8 0%, #6f42c1 100%);
    --gradient-card: linear-gradient(135deg, rgba(248, 177, 149, 0.1) 0%, rgba(53, 92, 125, 0.1) 100%);
    
    /* Light Theme Variables */
    --bg-color: #ffffff;
    --text-color: #333333;
    --card-bg: #ffffff;
    --border-color: #dee2e6;
    --shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
    --shadow-lg: 0 1rem 3rem rgba(0, 0, 0, 0.175);
    
    /* Typography */
    --font-family-base: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-size-base: 1rem;
    --line-height-base: 1.5;
    
    /* Spacing */
    --spacer: 1rem;
    --border-radius: 0.375rem;
    --border-radius-lg: 0.5rem;
    
    /* Transitions */
    --transition-base: all 0.3s ease-in-out;
}

/* Dark Theme Variables */
[data-theme="dark"] {
    --bg-color: #1a1a1a;
    --text-color: #ffffff;
    --card-bg: #2d2d2d;
    --border-color: #404040;
    --shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 1rem 3rem rgba(0, 0, 0, 0.4);
}

/* Base Styles */
body {
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--text-color);
    background-color: var(--bg-color);
    transition: var(--transition-base);
    overflow-x: hidden;
}

/* Background Gradient Animation */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-card);
    z-index: -1;
    animation: gradientShift 10s ease infinite;
}

@keyframes gradientShift {
    0%, 100% {
        background: var(--gradient-card);
    }
    50% {
        background: linear-gradient(135deg, rgba(53, 92, 125, 0.1) 0%, rgba(248, 177, 149, 0.1) 100%);
    }
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 0.5rem;
}

.display-4 {
    font-weight: 700;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

/* Gradient Backgrounds */
.bg-primary-gradient {
    background: var(--gradient-primary) !important;
}

.bg-secondary-gradient {
    background: var(--gradient-secondary) !important;
}

.bg-success-gradient {
    background: var(--gradient-success) !important;
}

.bg-warning-gradient {
    background: var(--gradient-warning) !important;
}

.bg-info-gradient {
    background: var(--gradient-info) !important;
}

.bg-gradient-card {
    background: var(--gradient-card) !important;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

/* Card Styles */
.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow);
    transition: var(--transition-base);
    overflow: hidden;
}

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

.card-header {
    border-bottom: 1px solid var(--border-color);
    background-color: rgba(0, 0, 0, 0.03);
}

[data-theme="dark"] .card-header {
    background-color: rgba(255, 255, 255, 0.05);
}

/* Form Styles */
.form-control {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    transition: var(--transition-base);
}

.form-control:focus {
    background-color: var(--card-bg);
    border-color: var(--color-primary);
    box-shadow: 0 0 0 0.2rem rgba(53, 92, 125, 0.25);
    color: var(--text-color);
}

.form-control::placeholder {
    color: rgba(var(--text-color), 0.6);
}

.input-group-text {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
}

.form-label {
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.form-text {
    color: rgba(var(--text-color), 0.7);
}

/* Button Styles */
.btn {
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: var(--transition-base);
    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 0.5s;
}

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

.btn-primary {
    background: var(--gradient-primary);
    border: none;
    color: white;
}

.btn-primary:hover {
    background: var(--gradient-secondary);
    transform: translateY(-1px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.btn-success {
    background: var(--gradient-success);
    border: none;
    color: white;
}

.btn-success:hover {
    background: linear-gradient(135deg, #20c997 0%, #28a745 100%);
    transform: translateY(-1px);
}

.btn-outline-primary {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.btn-outline-primary:hover {
    background: var(--gradient-primary);
    border-color: var(--color-primary);
}

/* Navigation Styles */
.navbar {
    box-shadow: var(--shadow);
    backdrop-filter: blur(10px);
}

.navbar-brand {
    font-size: 1.5rem;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

/* Alert Styles */
.alert {
    border-radius: var(--border-radius);
    border: none;
    box-shadow: var(--shadow);
}

.alert-success {
    background: linear-gradient(135deg, rgba(40, 167, 69, 0.1) 0%, rgba(32, 201, 151, 0.1) 100%);
    color: #155724;
    border-left: 4px solid #28a745;
}

.alert-danger {
    background: linear-gradient(135deg, rgba(220, 53, 69, 0.1) 0%, rgba(255, 107, 107, 0.1) 100%);
    color: #721c24;
    border-left: 4px solid #dc3545;
}

.alert-warning {
    background: linear-gradient(135deg, rgba(255, 193, 7, 0.1) 0%, rgba(253, 126, 20, 0.1) 100%);
    color: #856404;
    border-left: 4px solid #ffc107;
}

.alert-info {
    background: linear-gradient(135deg, rgba(23, 162, 184, 0.1) 0%, rgba(111, 66, 193, 0.1) 100%);
    color: #0c5460;
    border-left: 4px solid #17a2b8;
}

/* Results Styles */
.result-item {
    padding: 1rem;
    margin-bottom: 0.5rem;
    border-radius: var(--border-radius);
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: var(--transition-base);
}

.result-item:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateX(5px);
}

.result-value {
    font-size: 1.25rem;
    font-weight: 700;
    color: #28a745;
}

.result-negative {
    color: #dc3545;
}

/* Table Styles */
.table {
    background-color: var(--card-bg);
    color: var(--text-color);
}

.table th {
    background: var(--gradient-primary);
    color: white;
    border: none;
    font-weight: 600;
}

.table td {
    border-color: var(--border-color);
    vertical-align: middle;
}

.table-striped tbody tr:nth-of-type(odd) {
    background-color: rgba(0, 0, 0, 0.05);
}

[data-theme="dark"] .table-striped tbody tr:nth-of-type(odd) {
    background-color: rgba(255, 255, 255, 0.05);
}

/* History Item Styles */
.history-item {
    padding: 1rem;
    margin-bottom: 0.5rem;
    border-radius: var(--border-radius);
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    transition: var(--transition-base);
    cursor: pointer;
}

.history-item:hover {
    background: rgba(53, 92, 125, 0.1);
    transform: translateX(5px);
    box-shadow: var(--shadow);
}

.history-item-title {
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 0.25rem;
}

.history-item-price {
    font-size: 1.1rem;
    font-weight: 700;
    color: #28a745;
}

.history-item-date {
    font-size: 0.875rem;
    color: rgba(var(--text-color), 0.7);
}

.history-item-actions {
    margin-top: 0.5rem;
}

/* Modal Styles */
.modal-content {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
}

.modal-header {
    border-bottom: 1px solid var(--border-color);
}

.modal-footer {
    border-top: 1px solid var(--border-color);
}
.footer_link {
    color: white;
    text-decoration: none;
}

/* Offcanvas Styles */
.offcanvas {
    background-color: var(--card-bg);
    color: var(--text-color);
}

.offcanvas-header {
    border-bottom: 1px solid var(--border-color);
}

/* Accordion Styles */
.accordion-item {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
}

.accordion-button {
    background-color: var(--card-bg);
    color: var(--text-color);
    border: none;
}

.accordion-button:not(.collapsed) {
    background: var(--gradient-primary);
    color: white;
}

.accordion-button:focus {
    box-shadow: 0 0 0 0.2rem rgba(53, 92, 125, 0.25);
}

/* Tooltip Styles */
.tooltip {
    font-size: 0.875rem;
}

.tooltip-inner {
    background-color: var(--color-primary);
    border-radius: var(--border-radius);
    padding: 0.5rem 0.75rem;
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: #fff;
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding-left: 15px;
        padding-right: 15px;
    }
    
    .card {
        margin-bottom: 1rem;
    }
    
    .display-4 {
        font-size: 2.5rem;
    }
    
    .btn {
        width: 100%;
        margin-bottom: 0.5rem;
    }
    
    .btn-group .btn {
        width: auto;
        margin-bottom: 0;
    }
    
    .result-item {
        text-align: center;
    }
    
    .history-item {
        padding: 0.75rem;
    }
    
    .table-responsive {
        font-size: 0.875rem;
    }
}

@media (max-width: 576px) {
    .display-4 {
        font-size: 2rem;
    }
    
    .card-header h2,
    .card-header h3 {
        font-size: 1.25rem;
    }
    
    .btn-group {
        flex-direction: column;
    }
    
    .btn-group .btn {
        width: 100%;
        margin-bottom: 0.5rem;
    }
    
    .input-group {
        flex-direction: column;
    }
    
    .input-group .form-control,
    .input-group .input-group-text {
        width: 100%;
        border-radius: var(--border-radius);
    }
    
    .input-group .input-group-text {
        margin-bottom: -1px;
        border-bottom-left-radius: 0;
        border-bottom-right-radius: 0;
    }
    
    .input-group .form-control {
        border-top-left-radius: 0;
        border-top-right-radius: 0;
    }
}

/* Print Styles */
@media print {
    .navbar,
    .btn,
    .modal,
    .offcanvas,
    footer {
        display: none !important;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #000;
    }
    
    .card-header {
        background: #f8f9fa !important;
        color: #000 !important;
    }
    
    body {
        background: white !important;
        color: black !important;
    }
}

/* Accessibility Improvements */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Focus Styles */
.btn:focus,
.form-control:focus,
.form-select:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
    :root {
        --shadow: 0 0 0 1px #000;
        --shadow-lg: 0 0 0 2px #000;
    }
    
    .card {
        border: 2px solid #000;
    }
    
    .btn {
        border: 2px solid #000;
    }
}

/* Reduced Motion Support */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    body::before {
        animation: none;
    }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-color);
}

::-webkit-scrollbar-thumb {
    background: var(--gradient-primary);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gradient-secondary);
}

/* Selection Styles */
::selection {
    background: var(--color-primary);
    color: white;
}

::-moz-selection {
    background: var(--color-primary);
    color: white;
}