/* Sorting Efficiency Calculator Styles */

:root {
    /* Sorting Efficiency Theme Colors */
    --sorting-primary: #f59e0b;
    --sorting-secondary: #d97706;
    --sorting-accent: #f97316;
    --sorting-light: #fef3c7;
    --sorting-dark: #92400e;
    
    /* Base Colors - Enhanced for better contrast */
    --white: #ffffff;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #374151; /* Darkened for better contrast */
    --gray-700: #1f2937; /* Darkened for better contrast */
    --gray-800: #111827;
    --gray-900: #000000; /* Pure black for maximum contrast */
    
    /* Status Colors */
    --success: #10b981;
    --warning: #f59e0b;
    --error: #ef4444;
    --info: #3b82f6;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    
    /* Transitions */
    --transition: all 0.3s ease;
    --transition-fast: all 0.15s ease;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--gray-900);
    background: linear-gradient(135deg, var(--gray-50) 0%, var(--sorting-light) 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header Styles */
.header {
    background: var(--white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo h1 {
    color: var(--sorting-primary);
    font-size: 1.5rem;
    font-weight: 700;
}

.logo i {
    margin-right: 0.5rem;
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--gray-700);
    font-weight: 500;
    transition: var(--transition-fast);
}

.nav-link:hover {
    color: var(--sorting-primary);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--gray-700);
    cursor: pointer;
}

.mobile-menu {
    display: none;
    position: fixed;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--white);
    box-shadow: var(--shadow-lg);
    z-index: 99;
    transform: translateY(-100%);
    transition: var(--transition);
}

.mobile-menu.active {
    display: block;
    transform: translateY(0);
}

.mobile-menu-link {
    display: block;
    padding: 1rem;
    text-decoration: none;
    color: var(--gray-700);
    border-bottom: 1px solid var(--gray-200);
    transition: var(--transition-fast);
}

.mobile-menu-link:hover {
    background: var(--gray-50);
    color: var(--sorting-primary);
}

/* Breadcrumb */
.breadcrumb {
    background: var(--white);
    border-bottom: 1px solid var(--gray-200);
    padding: 0.75rem 0;
}

.breadcrumb a {
    color: var(--sorting-primary);
    text-decoration: none;
}

.breadcrumb .separator {
    margin: 0 0.5rem;
    color: var(--gray-400);
}

.breadcrumb .current {
    color: var(--gray-600);
}

/* Hero Section */
.hero {
    padding: 4rem 0;
    text-align: center;
}

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    color: var(--gray-900);
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--sorting-primary), var(--sorting-accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--gray-700); /* Improved contrast */
    max-width: 800px;
    margin: 0 auto 3rem;
    line-height: 1.7;
}

/* Statistics Cards */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.stat-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: 1rem;
    transition: var(--transition);
}

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

.stat-icon {
    width: 4rem;
    height: 4rem;
    background: linear-gradient(135deg, var(--sorting-primary), var(--sorting-accent));
    border-radius: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 1.5rem;
}

.stat-number {
    font-size: 2rem;
    font-weight: 800;
    color: var(--gray-900);
    line-height: 1;
}

.stat-label {
    color: var(--gray-700); /* Improved contrast */
    font-size: 0.875rem;
    font-weight: 500;
}

/* Calculator Section */
.calculator-section {
    padding: 4rem 0;
}

.calculator-container {
    background: var(--white);
    border-radius: 1rem;
    box-shadow: var(--shadow-lg);
    overflow: hidden;
}

/* Tab Navigation */
.tab-navigation {
    display: flex;
    background: var(--gray-100);
    padding: 0.5rem;
    gap: 0.25rem;
    overflow-x: auto;
}

.tab-btn {
    flex: 1;
    min-width: 120px;
    padding: 1rem;
    background: none;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    font-weight: 500;
    color: var(--gray-600);
}

.tab-btn:hover {
    background: var(--gray-200);
    color: var(--gray-800);
}

.tab-btn.active {
    background: var(--sorting-primary);
    color: var(--white);
    box-shadow: var(--shadow-sm);
}

.tab-text {
    display: block;
}

/* Tab Content */
.tab-content {
    padding: 2rem;
}

.tab-pane {
    display: none;
}

.tab-pane.active {
    display: block;
}

/* Form Styles */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

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

.form-group label {
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
}

.form-control {
    padding: 0.75rem;
    border: 2px solid var(--gray-300);
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: var(--transition-fast);
    background: var(--white);
}

.form-control:focus {
    outline: none;
    border-color: var(--sorting-primary);
    box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.1);
}

.form-control:hover {
    border-color: var(--gray-400);
}

/* Slider Styles */
.slider-container {
    position: relative;
}

.slider {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: var(--gray-300);
    outline: none;
    -webkit-appearance: none;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--sorting-primary);
    cursor: pointer;
    box-shadow: var(--shadow-sm);
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--sorting-primary);
    cursor: pointer;
    border: none;
    box-shadow: var(--shadow-sm);
}

.slider-labels {
    display: flex;
    justify-content: space-between;
    margin-top: 0.5rem;
    font-size: 0.75rem;
    color: var(--gray-500);
}

/* Quick Calculate Section */
.quick-calculate-section {
    margin-top: 2rem;
    padding: 1.5rem;
    background: var(--gray-50);
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
}

.quick-calculate-section h4 {
    color: var(--gray-900);
    margin-bottom: 1rem;
    font-weight: 600;
}

.quick-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
}

/* Live Preview */
.live-preview {
    border-top: 1px solid var(--gray-300);
    padding-top: 1.5rem;
}

.live-preview h5 {
    color: var(--gray-900);
    margin-bottom: 1rem;
    font-weight: 600;
    font-size: 1rem;
}

.preview-metrics {
    display: grid;
    gap: 0.75rem;
}

.preview-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem;
    background: var(--white);
    border-radius: 0.375rem;
    border: 1px solid var(--gray-200);
}

.preview-label {
    color: var(--gray-600);
    font-size: 0.875rem;
    font-weight: 500;
}

.preview-value {
    color: var(--gray-900);
    font-weight: 600;
    font-size: 0.875rem;
}

/* Button Styles */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.5rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    font-size: 0.875rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--sorting-primary), var(--sorting-secondary));
    color: var(--white);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--gray-200);
    color: var(--gray-700);
}

.btn-secondary:hover {
    background: var(--gray-300);
}

.btn-export {
    background: var(--white);
    color: var(--sorting-primary);
    border: 2px solid var(--sorting-primary);
}

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

.btn-template {
    background: var(--sorting-light);
    color: var(--sorting-dark);
    width: 100%;
    justify-content: center;
}

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

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

.btn-danger:hover {
    background: #dc2626;
}

.btn-accept {
    background: var(--sorting-primary);
    color: var(--white);
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 0.375rem;
    cursor: pointer;
    font-weight: 500;
}

/* Results Section */
.results-container {
    max-width: none;
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.results-header h3 {
    color: var(--gray-900);
    font-size: 1.5rem;
    font-weight: 700;
}

.results-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Charts Header */
.charts-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--gray-200);
}

.charts-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Processing Actions */
.processing-actions {
    margin-top: 2rem;
    padding: 1.5rem;
    background: var(--gray-50);
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
}

.processing-actions h4 {
    color: var(--gray-900);
    margin-bottom: 1rem;
    font-weight: 600;
}

.action-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.result-card {
    background: var(--gray-50);
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
    padding: 1.5rem;
    transition: var(--transition);
}

.result-card:hover {
    border-color: var(--sorting-primary);
    box-shadow: var(--shadow-md);
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--gray-200);
}

.result-header h4 {
    color: var(--gray-900);
    font-weight: 600;
}

.result-header i {
    color: var(--sorting-primary);
    font-size: 1.25rem;
}

.result-content {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0;
}

.result-label {
    color: var(--gray-600);
    font-weight: 500;
    font-size: 0.875rem;
}

.result-value {
    color: var(--gray-900);
    font-weight: 700;
    font-size: 1rem;
}

/* Export Section */
.export-section {
    background: var(--gray-50);
    padding: 1.5rem;
    border-radius: 0.75rem;
    border: 2px solid var(--gray-200);
}

.export-section h4 {
    margin-bottom: 1rem;
    color: var(--gray-900);
}

.export-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Charts Section */
.charts-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}

.chart-card {
    background: var(--gray-50);
    padding: 1.5rem;
    border-radius: 0.75rem;
    border: 2px solid var(--gray-200);
}

.chart-card h4 {
    margin-bottom: 1rem;
    color: var(--gray-900);
    text-align: center;
}

.chart-card canvas {
    max-height: 300px;
}

/* Templates Section */
.templates-container h3 {
    margin-bottom: 2rem;
    color: var(--gray-900);
    font-size: 1.5rem;
    font-weight: 700;
}

.templates-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
}

.template-card {
    background: var(--white);
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
    padding: 1.5rem;
    transition: var(--transition);
}

.template-card:hover {
    border-color: var(--sorting-primary);
    box-shadow: var(--shadow-md);
}

.template-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--gray-200);
}

.template-header h4 {
    color: var(--gray-900);
    font-weight: 600;
}

.template-header i {
    color: var(--sorting-primary);
    font-size: 1.5rem;
}

.template-content p {
    color: var(--gray-600);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.template-content ul {
    list-style: none;
    margin-bottom: 1.5rem;
}

.template-content li {
    color: var(--gray-600);
    padding: 0.25rem 0;
    position: relative;
    padding-left: 1.5rem;
}

.template-content li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success);
    font-weight: bold;
}

/* History Section */
.history-container h3 {
    margin-bottom: 2rem;
    color: var(--gray-900);
    font-size: 1.5rem;
    font-weight: 700;
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.history-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.history-empty {
    text-align: center;
    padding: 3rem;
    color: var(--gray-500);
}

.history-empty i {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--gray-400);
}

.history-item {
    background: var(--white);
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
    padding: 1.5rem;
    transition: var(--transition);
}

.history-item:hover {
    border-color: var(--sorting-primary);
    box-shadow: var(--shadow-sm);
}

.history-header-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.history-date {
    color: var(--gray-500);
    font-size: 0.875rem;
}

.history-actions {
    display: flex;
    gap: 0.5rem;
}

.history-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    color: var(--gray-600);
    font-size: 0.875rem;
}

/* Section Styles */
.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--gray-900);
    margin-bottom: 3rem;
}

/* How It Works Section */
.how-it-works {
    padding: 4rem 0;
    background: var(--white);
}

.steps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.step-card {
    text-align: center;
    padding: 2rem;
    border-radius: 1rem;
    background: var(--gray-50);
    border: 2px solid var(--gray-200);
    transition: var(--transition);
}

.step-card:hover {
    border-color: var(--sorting-primary);
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.step-number {
    width: 4rem;
    height: 4rem;
    background: linear-gradient(135deg, var(--sorting-primary), var(--sorting-accent));
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 800;
    margin: 0 auto 1.5rem;
}

.step-content h3 {
    color: var(--gray-900);
    margin-bottom: 1rem;
    font-weight: 600;
}

.step-content p {
    color: var(--gray-600);
    line-height: 1.6;
}

/* Use Cases Section */
.use-cases {
    padding: 4rem 0;
    background: var(--gray-50);
}

.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.use-case-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow-md);
    text-align: center;
    transition: var(--transition);
}

.use-case-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.use-case-icon {
    width: 4rem;
    height: 4rem;
    background: linear-gradient(135deg, var(--sorting-primary), var(--sorting-accent));
    color: var(--white);
    border-radius: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin: 0 auto 1.5rem;
}

.use-case-card h3 {
    color: var(--gray-900);
    margin-bottom: 1rem;
    font-weight: 600;
}

.use-case-card p {
    color: var(--gray-600);
    line-height: 1.6;
}

/* Related Calculators Section */
.related-calculators {
    padding: 4rem 0;
    background: var(--white);
}

.calculators-header {
    text-align: center;
    margin-bottom: 3rem;
}

.calculators-subtitle {
    font-size: 1.125rem;
    color: var(--gray-700);
    max-width: 800px;
    margin: 0 auto;
    line-height: 1.6;
}

.calculators-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.calculator-category {
    background: var(--gray-50);
    border: 2px solid var(--gray-200);
    border-radius: 1rem;
    padding: 2rem;
    transition: var(--transition);
}

.calculator-category:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--sorting-primary);
}

.calculator-category[data-category="filling"]:hover {
    border-color: #3b82f6;
    background: linear-gradient(135deg, #eff6ff, #dbeafe);
}

.calculator-category[data-category="cartoning"]:hover {
    border-color: #10b981;
    background: linear-gradient(135deg, #ecfdf5, #d1fae5);
}

.calculator-category[data-category="wrapping"]:hover {
    border-color: #8b5cf6;
    background: linear-gradient(135deg, #f5f3ff, #ede9fe);
}

.calculator-category[data-category="labeling"]:hover {
    border-color: #f59e0b;
    background: linear-gradient(135deg, #fffbeb, #fef3c7);
}

.calculator-category[data-category="quality"]:hover {
    border-color: #ef4444;
    background: linear-gradient(135deg, #fef2f2, #fecaca);
}

.calculator-category[data-category="material"]:hover {
    border-color: #6366f1;
    background: linear-gradient(135deg, #eef2ff, #e0e7ff);
}

.category-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--gray-900);
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.category-icon {
    font-size: 2rem;
}

.category-links {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.calculator-link {
    display: block;
    padding: 0.5rem;
    border-radius: 0.5rem;
    text-decoration: none;
    color: var(--gray-700);
    font-weight: 500;
    transition: var(--transition-fast);
}

.calculator-link:hover {
    background: var(--sorting-light);
    color: var(--sorting-dark);
    transform: translateX(4px);
}

/* FAQ Section */
.faq {
    padding: 4rem 0 2rem 0; /* Reduced bottom padding */
    background: var(--gray-50);
}

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

.faq-item {
    background: var(--white);
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
    margin-bottom: 1rem;
    overflow: hidden;
    transition: var(--transition);
}

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

.faq-question {
    padding: 1.5rem;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--white);
    transition: var(--transition-fast);
}

.faq-question:hover {
    background: var(--gray-50);
}

.faq-question h3 {
    color: var(--gray-900);
    font-weight: 600;
    font-size: 1.125rem;
    margin: 0;
}

.faq-question i {
    color: var(--sorting-primary);
    transition: var(--transition-fast);
}

.faq-item.active .faq-question i {
    transform: rotate(180deg);
}

.faq-answer {
    padding: 0 1.5rem;
    max-height: 0;
    overflow: hidden;
    transition: var(--transition);
}

.faq-item.active .faq-answer {
    padding: 0 1.5rem 1.5rem;
    max-height: 200px;
}

.faq-answer p {
    color: var(--gray-600);
    line-height: 1.6;
    margin: 0;
}

/* Footer */
.footer {
    background: var(--gray-900);
    color: var(--white);
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: var(--white);
}

.footer-section h3 {
    color: var(--sorting-primary);
    font-size: 1.5rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: var(--gray-400);
    text-decoration: none;
    transition: var(--transition-fast);
}

.footer-section a:hover {
    color: var(--sorting-primary);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid var(--gray-700);
    color: var(--gray-400);
}

/* Notification */
.notification {
    position: fixed;
    top: 2rem;
    right: 2rem;
    background: var(--white);
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
    padding: 1rem 1.5rem;
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    transform: translateX(400px);
    transition: var(--transition);
    max-width: 400px;
}

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

.notification.success {
    border-color: var(--success);
    background: #f0fdf4;
}

.notification.error {
    border-color: var(--error);
    background: #fef2f2;
}

.notification.warning {
    border-color: var(--warning);
    background: #fffbeb;
}

.notification-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

.notification-message {
    color: var(--gray-900);
    font-weight: 500;
}

.notification-close {
    background: none;
    border: none;
    font-size: 1.25rem;
    cursor: pointer;
    color: var(--gray-500);
    padding: 0;
    width: 1.5rem;
    height: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Privacy Banner */
.privacy-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--gray-900);
    color: var(--white);
    padding: 1rem;
    z-index: 1000;
    transform: translateY(100%);
    transition: var(--transition);
}

.privacy-banner.show {
    transform: translateY(0);
}

.privacy-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    gap: 2rem;
    flex-wrap: wrap;
}

.privacy-actions {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.privacy-link {
    color: var(--gray-300);
    text-decoration: underline;
}

/* Loading States */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 2rem;
    height: 2rem;
    margin: -1rem 0 0 -1rem;
    border: 3px solid var(--gray-300);
    border-top-color: var(--sorting-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 0.75rem;
    }
    
    .nav {
        display: none;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .stat-card {
        padding: 1.5rem;
    }
    
    .tab-navigation {
        flex-wrap: wrap;
    }
    
    .tab-btn {
        min-width: 100px;
        padding: 0.75rem 0.5rem;
    }
    
    .tab-text {
        display: none;
    }
    
    .tab-content {
        padding: 1rem;
    }
    
    .form-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .results-header {
        flex-direction: column;
        align-items: stretch;
    }
    
    .results-actions {
        justify-content: center;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .charts-container {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .templates-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .steps-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .use-cases-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
    
    .calculators-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .export-buttons {
        flex-direction: column;
    }
    
    .privacy-content {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
    }
    
    .notification {
        top: 1rem;
        right: 1rem;
        left: 1rem;
        max-width: none;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 2rem 0;
    }
    
    .calculator-section {
        padding: 2rem 0;
    }
    
    .how-it-works,
    .use-cases,
    .related-calculators,
    .faq {
        padding: 2rem 0;
    }
    
    .section-title {
        font-size: 1.75rem;
        margin-bottom: 2rem;
    }
    
    .result-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.25rem;
    }
    
    .step-card,
    .use-case-card {
        padding: 1.5rem;
    }
    
    .template-card {
        padding: 1rem;
    }

    .navigation-buttons {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-btn {
        max-width: none;
    }

    .nav-btn-next {
        text-align: left;
        justify-content: flex-start;
    }
}

/* Extra small screens */
@media (max-width: 640px) {
    .use-cases-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
}

/* Print Styles */
@media print {
    .header,
    .mobile-menu,
    .breadcrumb,
    .tab-navigation,
    .export-section,
    .footer,
    .notification,
    .privacy-banner {
        display: none !important;
    }
    
    .calculator-container {
        box-shadow: none;
        border: 1px solid var(--gray-300);
    }
    
    .tab-pane {
        display: block !important;
    }
    
    .results-grid {
        break-inside: avoid;
    }
    
    .result-card {
        break-inside: avoid;
        margin-bottom: 1rem;
    }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    :root {
        --gray-300: #000000;
        --gray-600: #000000;
        --gray-700: #000000;
        --gray-900: #000000;
    }
    
    .form-control {
        border-width: 3px;
    }
    
    .btn {
        border-width: 2px;
        border-style: solid;
    }
}

/* Navigation Section */
.navigation-section {
    padding: 2rem 0;
    background: var(--gray-50);
    border-top: 1px solid var(--gray-200);
}

.navigation-buttons {
    display: flex;
    justify-content: space-between;
    gap: 2rem;
    max-width: 800px;
    margin: 0 auto;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    background: var(--white);
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
    text-decoration: none;
    color: var(--gray-700);
    transition: var(--transition);
    flex: 1;
    max-width: 300px;
}

.nav-btn:hover {
    border-color: var(--sorting-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.nav-btn-prev {
    justify-content: flex-start;
}

.nav-btn-next {
    justify-content: flex-end;
    text-align: right;
}

.nav-btn-content {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.nav-btn-label {
    font-size: 0.75rem;
    color: var(--gray-500);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.nav-btn-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--gray-900);
}

.nav-btn i {
    font-size: 1.25rem;
    color: var(--sorting-primary);
}

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