/* Modern Clean Design */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --border-color: #e5e7eb;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --success-color: #10b981;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-light);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
header {
    background: linear-gradient(135deg, #1e40af 0%, #2563eb 100%);
    color: white;
    padding: 48px 0;
    box-shadow: var(--shadow-md);
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 8px;
    letter-spacing: -0.02em;
}

.tagline {
    font-size: 1.125rem;
    opacity: 0.9;
    font-weight: 400;
}

/* Main Content */
.main-content {
    padding: 48px 24px;
    max-width: 1200px;
    margin: 0 auto;
}

/* Intro Section */
.intro-section {
    background: var(--bg-white);
    padding: 48px;
    border-radius: 16px;
    box-shadow: var(--shadow-sm);
    margin-bottom: 32px;
    border: 1px solid var(--border-color);
}

.intro-section h2 {
    font-size: 1.875rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.intro-section > p {
    font-size: 1.125rem;
    line-height: 1.75;
    color: var(--text-light);
    margin-bottom: 32px;
}

/* Use Cases */
.use-cases {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
    margin-top: 32px;
}

.use-case {
    padding: 24px;
    background: var(--bg-light);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

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

.use-case .icon {
    font-size: 2rem;
    margin-bottom: 12px;
}

.use-case h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.use-case p {
    color: var(--text-light);
    font-size: 0.9375rem;
    line-height: 1.6;
}

/* Calculator Section */
.calculator-section, .holiday-section {
    background: var(--bg-white);
    padding: 48px;
    border-radius: 16px;
    box-shadow: var(--shadow-sm);
    margin-bottom: 32px;
    border: 1px solid var(--border-color);
}

.calculator-section h2, .holiday-section h2 {
    font-size: 1.875rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

/* Tabs */
.calculator-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 32px;
    border-bottom: 1px solid var(--border-color);
}

.tab-btn {
    padding: 12px 24px;
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-light);
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
}

.tab-btn:hover {
    color: var(--text-dark);
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.tab-content {
    display: none;
}

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

.tab-description {
    color: var(--text-light);
    margin-bottom: 24px;
    font-size: 0.9375rem;
}

/* Forms */
.calc-form, .search-form {
    margin-bottom: 24px;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    align-items: end;
}

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

.form-group label {
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--text-dark);
    font-size: 0.875rem;
}

.form-control {
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.2s ease;
    background: var(--bg-white);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.checkbox-group {
    display: flex;
    align-items: center;
}

.checkbox-group label {
    flex-direction: row;
    align-items: center;
    cursor: pointer;
    margin-bottom: 0;
}

.checkbox-group input[type="checkbox"] {
    width: 18px;
    height: 18px;
    margin-right: 8px;
    cursor: pointer;
    accent-color: var(--primary-color);
}

.checkbox-group span {
    font-weight: 400;
    font-size: 0.9375rem;
}

/* Buttons */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
    display: inline-block;
}

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

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

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--bg-white);
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

.btn-secondary:hover {
    background: var(--bg-light);
}

/* Loading */
.loading {
    text-align: center;
    padding: 40px;
}

.spinner {
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--primary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 0.8s linear infinite;
    margin: 0 auto 16px;
}

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

/* Results */
.calc-results, .results-section {
    margin-top: 32px;
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 24px;
    flex-wrap: wrap;
    gap: 16px;
}

.results-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-dark);
}

.result-card {
    background: var(--bg-light);
    padding: 24px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    margin-bottom: 16px;
}

.result-primary {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 16px;
}

.result-metrics {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 16px;
    margin-bottom: 16px;
}

.metric {
    background: var(--bg-white);
    padding: 16px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.metric-label {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-bottom: 4px;
}

.metric-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
}

.result-note {
    background: #dbeafe;
    padding: 16px;
    border-radius: 8px;
    color: #1e40af;
    font-size: 0.9375rem;
    line-height: 1.6;
}

.holiday-list {
    margin-top: 16px;
}

.holiday-item {
    padding: 8px 0;
    border-bottom: 1px solid var(--border-color);
    font-size: 0.9375rem;
    color: var(--text-light);
}

.holiday-item:last-child {
    border-bottom: none;
}

/* Tables */
.table-container {
    overflow-x: auto;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-white);
}

thead {
    background: var(--bg-light);
    border-bottom: 1px solid var(--border-color);
}

thead th {
    padding: 16px;
    text-align: left;
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-dark);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

tbody tr {
    border-bottom: 1px solid var(--border-color);
    transition: background-color 0.15s ease;
}

tbody tr:hover {
    background-color: var(--bg-light);
}

tbody td {
    padding: 16px;
    color: var(--text-dark);
    font-size: 0.9375rem;
}

tbody tr:last-child {
    border-bottom: none;
}

/* Content Section */
.content-section {
    background: var(--bg-white);
    padding: 48px;
    border-radius: 16px;
    box-shadow: var(--shadow-sm);
    margin-bottom: 32px;
    border: 1px solid var(--border-color);
}

.content-section h2 {
    font-size: 1.875rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

.content-section h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-top: 32px;
    margin-bottom: 16px;
}

.content-section h4 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-top: 24px;
    margin-bottom: 12px;
}

.content-section p {
    line-height: 1.75;
    color: var(--text-light);
    margin-bottom: 16px;
}

.content-section ul {
    margin: 16px 0 24px 24px;
    line-height: 1.75;
}

.content-section li {
    margin-bottom: 8px;
    color: var(--text-light);
}

.content-section li strong {
    color: var(--text-dark);
    font-weight: 600;
}

/* Advertisements - Optimized for Maximum Revenue */
.ad-container {
    margin: 32px 0;
    display: flex;
    justify-content: center;
}

.ad-container ins {
    display: block !important;
    margin: 0 auto;
}

/* In-Content Ads (336x280 and 300x250) - High CTR Placements */
.ad-in-content {
    margin: 40px auto;
    display: flex;
    justify-content: center;
    padding: 24px 0;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

/* Sidebar Ads - Fixed Position for High Visibility */
.ad-sidebar {
    position: fixed;
    top: 50%;
    transform: translateY(-50%);
    z-index: 100;
}

.ad-sidebar-right {
    right: 20px;
}

/* Mobile Sticky Bottom Ad - Top Mobile Revenue Generator */
.ad-mobile-sticky {
    display: none; /* Hidden on desktop */
}

@media (max-width: 768px) {
    .ad-mobile-sticky {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        background: white;
        padding: 8px 0;
        box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
        z-index: 1000;
        display: flex;
        justify-content: center;
    }
    
    /* Add padding to body to prevent content being hidden */
    body {
        padding-bottom: 66px;
    }
}

/* Footer */
footer {
    background: var(--text-dark);
    color: white;
    padding: 48px 0 24px;
    margin-top: 64px;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.disclaimer {
    background: rgba(255, 255, 255, 0.05);
    padding: 24px;
    border-radius: 12px;
    margin-bottom: 24px;
    line-height: 1.75;
    font-size: 0.875rem;
}

.disclaimer strong {
    color: #fbbf24;
    font-weight: 600;
}

.copyright {
    text-align: center;
    opacity: 0.6;
    font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 1600px) {
    /* Hide sidebar on smaller screens to maintain clean layout */
    .ad-sidebar {
        display: none;
    }
}

@media (min-width: 1601px) {
    /* Show right sidebar only on very large screens (300x600 needs space) */
    .ad-sidebar-right {
        display: block;
    }
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

    .tagline {
        font-size: 1rem;
    }

    .intro-section, .calculator-section, .holiday-section, .content-section {
        padding: 32px 24px;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .use-cases {
        grid-template-columns: 1fr;
    }

    .results-header {
        flex-direction: column;
        align-items: stretch;
    }

    .calculator-tabs {
        flex-direction: column;
    }

    .tab-btn {
        border-bottom: 1px solid var(--border-color);
        border-left: 2px solid transparent;
    }

    .tab-btn.active {
        border-left-color: var(--primary-color);
        border-bottom-color: var(--border-color);
    }
}

@media (max-width: 480px) {
    .main-content {
        padding: 24px 16px;
    }

    .container {
        padding: 0 16px;
    }

    header h1 {
        font-size: 1.75rem;
    }

    .intro-section h2, .calculator-section h2, .holiday-section h2, .content-section h2 {
        font-size: 1.5rem;
    }
}