/* ==========================================================================
   CalcCompare - Calculadora PayPal Design System (design.md & Rules.md aligned)
   High-contrast, dark-mode fintech styling (#0B1120 / #111827 / #1E293B)
   ========================================================================== */

:root {
  --bg-main: #0B1120;
  --bg-card: #111827;
  --bg-surface: #1E293B;
  --bg-surface-hover: #334155;
  --header-bg: #0B1120;
  --footer-bg: #070B14;
  --border-light: #1E293B;
  --border-strong: #334155;
  --text-heading: #FFFFFF;
  --text-body: #CBD5E1;
  --text-muted: #94A3B8;
  --text-light: #FFFFFF;
  --accent-emerald: #10B981;
  --accent-emerald-glow: rgba(16, 185, 129, 0.15);
  --accent-blue: #2563eb;
  --accent-blue-hover: #1d4ed8;
  --accent-cyan: #06b6d4;
  --badge-bg: rgba(37, 99, 235, 0.15);
  --badge-border: rgba(59, 130, 246, 0.3);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-full: 9999px;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  --shadow-card: 0 10px 25px -5px rgba(0, 0, 0, 0.5), 0 8px 10px -6px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 20px -3px rgba(37, 99, 235, 0.25);
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-main);
  color: var(--text-body);
  line-height: 1.625;
  font-size: 1rem;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Accessibility Skip Link */
.skip-link {
  position: absolute;
  top: -60px;
  left: 1rem;
  background: var(--accent-blue);
  color: #ffffff;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-sm);
  z-index: 1000;
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.2s ease;
}
.skip-link:focus {
  top: 1rem;
  transform: translateY(0);
}

/* Header & Navigation */
header {
  background-color: rgba(11, 17, 32, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  position: sticky;
  top: 0;
  z-index: 50;
  padding: 0.875rem 1.25rem;
}

.header-container {
  max-width: 1180px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  text-decoration: none;
  color: var(--text-heading);
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.025em;
  transition: opacity 0.2s ease;
}
.brand:hover {
  opacity: 0.9;
}

.brand-icon {
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, #2563eb, #10B981);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: #fff;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.4);
}

.site-badge-header {
  background: rgba(37, 99, 235, 0.15);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: #60a5fa;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-full);
  margin-left: 0.25rem;
}

/* Breadcrumbs */
nav.breadcrumbs {
  max-width: 1180px;
  margin: 1.25rem auto 0;
  padding: 0 1.25rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
}

nav.breadcrumbs a {
  color: var(--text-body);
  text-decoration: none;
  transition: color 0.15s ease;
}
nav.breadcrumbs a:hover {
  color: #60a5fa;
  text-decoration: underline;
}
nav.breadcrumbs span {
  color: var(--border-strong);
}
nav.breadcrumbs strong {
  color: var(--text-light);
  font-weight: 600;
}

/* Main Container */
main {
  max-width: 1180px;
  width: 100%;
  margin: 1.5rem auto;
  padding: 0 1.25rem 3rem;
  flex: 1;
}

/* Typography Hierarchy */
h1 {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.03em;
  color: var(--text-heading);
  margin-bottom: 0.75rem;
}

@media (max-width: 640px) {
  h1 { font-size: 1.75rem; }
}

.intro {
  font-size: 1.125rem;
  color: #cbd5e1;
  line-height: 1.7;
  max-width: 840px;
  margin-bottom: 2rem;
}

.intro strong {
  color: #ffffff;
}

h2 {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-heading);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-heading);
  margin-bottom: 0.75rem;
}

p {
  margin-bottom: 1.25rem;
  color: var(--text-body);
  font-size: 1rem;
  line-height: 1.7;
}

p strong {
  color: var(--text-light);
}

ul, ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
  color: var(--text-body);
}

li {
  margin-bottom: 0.5rem;
  line-height: 1.65;
}

li strong {
  color: var(--text-light);
}

a {
  color: #60a5fa;
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.15s ease;
}
a:hover {
  color: #93c5fd;
}

/* Modern Fintech Calculator Card */
.calculator-card-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-card);
  margin-bottom: 2.5rem;
  position: relative;
  overflow: hidden;
}

.calculator-card-wrapper::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #2563eb, #10B981, #06b6d4);
}

.calc-header-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border-light);
  margin-bottom: 1.5rem;
}

.calc-title-badge {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text-heading);
}

.live-indicator {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--accent-emerald);
  background: var(--accent-emerald-glow);
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-full);
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.live-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent-emerald);
  box-shadow: 0 0 8px var(--accent-emerald);
  animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.85); }
}

/* Quick Currency Chips */
.currency-chips-label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}

.currency-chips-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.currency-chip {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  color: var(--text-body);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  transition: all 0.15s ease;
}

.currency-chip:hover {
  background: var(--bg-surface-hover);
  border-color: var(--accent-blue);
  color: var(--text-heading);
  transform: translateY(-1px);
}

.currency-chip.active,
.currency-chip[aria-pressed="true"] {
  background: #2563eb;
  border-color: #60a5fa;
  color: #ffffff;
  font-weight: 700;
  box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.4), 0 2px 8px rgba(0, 0, 0, 0.4);
}

/* 2-Column Calculator Layout */
.calc-interactive-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.75rem;
}

@media (max-width: 820px) {
  .calc-interactive-grid {
    grid-template-columns: 1fr;
  }
}

.calc-panel {
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 1.35rem;
  display: flex;
  flex-direction: column;
  gap: 1.15rem;
}

.calc-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-light);
  padding-bottom: 0.75rem;
}

.calc-panel-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-heading);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.form-label {
  font-size: 0.825rem;
  font-weight: 600;
  color: #cbd5e1;
  display: flex;
  justify-content: space-between;
}

.form-label-hint {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: normal;
}

.input-with-symbol {
  position: relative;
  display: flex;
  align-items: center;
}

.input-currency-symbol {
  position: absolute;
  left: 0.875rem;
  color: var(--text-muted);
  font-weight: 700;
  font-size: 1rem;
  pointer-events: none;
}

.calc-input {
  width: 100%;
  background: var(--bg-main);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 0.75rem 0.875rem 0.75rem 2.25rem;
  font-size: 1.15rem;
  font-weight: 700;
  color: #ffffff;
  font-family: var(--font-sans);
  transition: all 0.15s ease;
}

.calc-input:focus {
  outline: none;
  border-color: #3b82f6;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.25);
  background: #0d1527;
}

.calc-select {
  width: 100%;
  background: var(--bg-main);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 0.65rem 0.875rem;
  font-size: 0.95rem;
  font-weight: 600;
  color: #ffffff;
  cursor: pointer;
  transition: border-color 0.15s ease;
}
.calc-select:focus {
  outline: none;
  border-color: #3b82f6;
}

/* Preset Buttons (Unified with currency chips) */
.preset-buttons-row {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.preset-btn {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  color: var(--text-body);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  transition: all 0.15s ease;
}
.preset-btn:hover {
  background: var(--bg-surface-hover);
  color: var(--text-heading);
  border-color: var(--accent-blue);
}
.preset-btn.active,
.preset-btn[aria-pressed="true"] {
  background: #2563eb;
  border-color: #60a5fa;
  color: #ffffff;
  font-weight: 700;
}

/* Results Display Box */
.calc-result-card {
  background: linear-gradient(145deg, rgba(30, 41, 59, 0.8), rgba(15, 23, 42, 0.95));
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.result-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 0.75rem;
  position: relative;
}

.result-row::before {
  content: "";
  flex: 1;
  order: 2;
  border-bottom: 1px dotted var(--border-strong);
  margin: 0 0.5rem;
  opacity: 0.6;
  align-self: center;
}

.result-row.main-result {
  padding-bottom: 0.75rem;
  border-bottom: 1px dashed var(--border-light);
}

.result-caption {
  order: 1;
  font-size: 0.875rem;
  color: var(--text-body);
  display: flex;
  align-items: center;
  gap: 0.35rem;
  white-space: nowrap;
}

.result-big-value {
  order: 3;
  font-size: 1.5rem;
  font-weight: 800;
  color: #ffffff;
  letter-spacing: -0.02em;
  white-space: nowrap;
}
.result-big-value.green {
  color: #34d399;
}
.result-big-value.blue {
  color: #60a5fa;
}

.result-fee-value {
  order: 3;
  font-size: 1rem;
  font-weight: 700;
  color: #f87171;
  white-space: nowrap;
}

.result-percentage-bar {
  width: 100%;
  height: 6px;
  background: #1e293b;
  border-radius: 3px;
  overflow: hidden;
  margin-top: 0.25rem;
  display: flex;
}
.bar-net {
  background: #10B981;
  height: 100%;
}
.bar-fee {
  background: #ef4444;
  height: 100%;
}

.copy-action-btn {
  background: var(--accent-blue);
  color: #ffffff;
  border: none;
  padding: 0.6rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 700;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  transition: all 0.15s ease;
  width: 100%;
}
.copy-action-btn:hover {
  background: var(--accent-blue-hover);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.4);
}
.copy-action-btn:active {
  transform: scale(0.98);
}

/* Fee Formula Display Box - Collapsible to reduce visual noise */
.formula-accordion {
  background: rgba(15, 23, 42, 0.5);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 0.5rem 0.75rem;
  margin-top: 0.75rem;
  font-size: 0.75rem;
  color: var(--text-muted);
}
.formula-accordion-toggle {
  cursor: pointer;
  font-weight: 600;
  color: var(--accent-blue);
  user-select: none;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.formula-accordion-toggle::-webkit-details-marker {
  display: none;
}
.formula-accordion-toggle::after {
  content: "▾";
  font-size: 0.75rem;
  color: var(--text-muted);
}
.formula-content {
  margin-top: 0.5rem;
  padding-top: 0.5rem;
  border-top: 1px solid var(--border-light);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}
.formula-display-box {
  background: rgba(15, 23, 42, 0.5);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.85rem;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.75rem;
}
.formula-code {
  font-family: var(--font-mono);
  background: #090e1a;
  padding: 0.2rem 0.4rem;
  border-radius: var(--radius-sm);
  color: #38bdf8;
  font-weight: 600;
  display: inline-block;
  margin: 0.15rem 0;
  font-size: 0.75rem;
}

/* Tables (Contrast Compliant) */
.fee-table-wrapper {
  overflow-x: auto;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  margin: 1.5rem 0;
  background: var(--bg-card);
}

.fee-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

.fee-table th {
  background: #1e293b;
  color: #ffffff;
  font-weight: 700;
  padding: 0.875rem 1rem;
  border-bottom: 2px solid var(--border-strong);
  white-space: nowrap;
}

.fee-table td {
  padding: 0.875rem 1rem;
  border-bottom: 1px solid var(--border-light);
  color: #e2e8f0;
}

.fee-table tbody tr:hover {
  background: rgba(30, 41, 59, 0.5);
}

.fee-table td strong {
  color: #ffffff;
}

/* FAQ Accordion */
.faq-section {
  margin-top: 3rem;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-top: 1.25rem;
}

details.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  transition: all 0.2s ease;
}

details.faq-item[open] {
  border-color: #3b82f6;
  background: #131c31;
}

summary.faq-question {
  font-weight: 700;
  font-size: 1rem;
  color: #f1f5f9;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  list-style: none;
  user-select: none;
}

summary.faq-question::-webkit-details-marker {
  display: none;
}

summary.faq-question::after {
  content: "+";
  font-size: 1.25rem;
  color: #60a5fa;
  font-weight: 400;
  transition: transform 0.2s ease;
}

details[open] summary.faq-question::after {
  content: "−";
  transform: rotate(180deg);
}

.faq-answer {
  margin-top: 0.875rem;
  padding-top: 0.875rem;
  border-top: 1px solid var(--border-light);
  color: #cbd5e1;
  font-size: 0.95rem;
  line-height: 1.7;
}

.faq-answer code {
  background: #0f172a;
  padding: 0.2rem 0.4rem;
  border-radius: var(--radius-sm);
  color: var(--accent-blue);
  font-family: var(--font-mono);
}

/* Author Bio Section (EEAT) */
.author-bio-card {
  margin-top: 3.5rem;
  padding: 1.5rem;
  background: linear-gradient(145deg, #111827, #0b1120);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

@media (max-width: 640px) {
  .author-bio-card {
    flex-direction: column;
    text-align: center;
  }
}

.author-avatar {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: linear-gradient(135deg, #2563eb, #10B981);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
  color: #fff;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.author-name {
  color: #ffffff;
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.author-desc {
  color: var(--text-body);
  font-size: 0.875rem;
  margin-bottom: 0.4rem;
  line-height: 1.5;
}

.author-dates {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent-emerald);
}

/* Related Calculators Grid (Rules.md: 4-6 links) */
.related-section {
  margin-top: 3rem;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1rem;
  margin-top: 1.25rem;
}

.related-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 1.15rem;
  text-decoration: none;
  color: var(--text-light);
  display: flex;
  align-items: center;
  gap: 0.75rem;
  transition: all 0.2s ease;
}

.related-card:hover {
  background: #172033;
  border-color: #3b82f6;
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.related-card-icon {
  font-size: 1.5rem;
  flex-shrink: 0;
}

.related-card-title {
  font-weight: 700;
  font-size: 0.925rem;
  color: #ffffff;
  line-height: 1.3;
}

.related-card-sub {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.15rem;
}

/* CTA Block */
.cta-banner {
  margin-top: 3.5rem;
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.2), rgba(16, 185, 129, 0.15));
  border: 1px solid rgba(59, 130, 246, 0.3);
  border-radius: var(--radius-lg);
  padding: 2.25rem 1.5rem;
  text-align: center;
}

.cta-banner h3 {
  font-size: 1.35rem;
  color: #ffffff;
  margin-bottom: 0.5rem;
}

.cta-banner p {
  color: #cbd5e1;
  max-width: 600px;
  margin: 0 auto 1.25rem;
}

.cta-button {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: #2563eb;
  color: #ffffff;
  font-weight: 700;
  padding: 0.85rem 1.75rem;
  border-radius: var(--radius-full);
  text-decoration: none;
  font-size: 0.95rem;
  transition: all 0.2s ease;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.4);
}
.cta-button:hover {
  background: #1d4ed8;
  transform: scale(1.02);
  color: #ffffff;
}

/* Footer */
footer {
  background-color: var(--footer-bg);
  border-top: 1px solid var(--border-light);
  color: var(--text-muted);
  padding: 3rem 1.25rem 2rem;
  margin-top: auto;
  contain: layout;
  min-height: 320px;
}

.footer-container {
  max-width: 1180px;
  margin: 0 auto;
}

.footer-columns {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border-light);
}

@media (max-width: 768px) {
  .footer-columns {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

.footer-brand-title {
  color: #ffffff;
  font-weight: 800;
  font-size: 1.15rem;
  margin-bottom: 0.5rem;
}

.footer-col-title {
  color: #ffffff;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.75rem;
}

.footer-links-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-links-list a {
  color: #94a3b8;
  text-decoration: none;
  font-size: 0.85rem;
  transition: color 0.15s ease;
}
.footer-links-list a:hover {
  color: #ffffff;
  text-decoration: underline;
}

.footer-bottom-bar {
  padding-top: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer-legal-links {
  display: flex;
  gap: 1rem;
}
.footer-legal-links a {
  color: var(--text-muted);
  text-decoration: none;
}
.footer-legal-links a:hover {
  color: #ffffff;
}

/* ==========================================================================
   PayPal Articles & Guides Section Styles (PRD.md & design.md aligned)
   ========================================================================== */

.article-content-wrapper, .hub-container {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1rem 4rem;
  width: 100%;
}

.article-category-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #38bdf8;
  margin-bottom: 0.75rem;
}

.article-meta-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.article-banner-wrapper {
  width: 100%;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-light);
  margin-bottom: 2rem;
  background-color: var(--bg-card);
}

.article-featured-img {
  width: 100%;
  height: auto;
  aspect-ratio: 1200 / 630;
  display: block;
  object-fit: cover;
}

.quick-answer-card {
  background: rgba(37, 99, 235, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.3);
  border-left: 4px solid var(--accent-blue);
  border-radius: var(--radius-sm);
  padding: 1.25rem;
  margin-bottom: 2rem;
}

.quick-answer-title {
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  color: #60a5fa;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}

.article-body {
  font-size: 1.05rem;
  line-height: 1.75;
  color: var(--text-light);
}

.article-body h2 {
  font-size: 1.5rem;
  font-weight: 800;
  color: #ffffff;
  margin-top: 2rem;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.article-body p {
  margin-bottom: 1.25rem;
}

.formula-box {
  background: var(--bg-card);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--accent-blue);
  margin: 1.5rem 0;
  text-align: center;
}

.table-container {
  overflow-x: auto;
  margin: 1.5rem 0 2rem;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
}

.table-container table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.9rem;
}

.table-container th, .table-container td {
  padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--border-light);
}

.table-container th {
  background: var(--bg-surface);
  color: #ffffff;
  font-weight: 700;
}

.table-container tr:last-child td {
  border-bottom: none;
}

.calculator-cta-card {
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.15) 0%, rgba(16, 185, 129, 0.1) 100%);
  border: 1.5px solid rgba(59, 130, 246, 0.4);
  border-radius: var(--radius-md);
  padding: 2rem;
  margin: 3rem 0;
  text-align: center;
}

.calculator-cta-card h3 {
  font-size: 1.35rem;
  color: #ffffff;
  margin-bottom: 0.5rem;
}

.calculator-cta-card p {
  color: var(--text-body);
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.cta-buttons {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.cta-primary-btn {
  background: var(--accent-blue);
  color: #ffffff;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 700;
  text-decoration: none;
  transition: opacity 0.15s ease;
  display: inline-block;
}
.cta-primary-btn:hover {
  opacity: 0.9;
}

.cta-secondary-btn {
  background: var(--bg-surface);
  color: #ffffff;
  border: 1px solid var(--border-strong);
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 700;
  text-decoration: none;
  transition: opacity 0.15s ease;
  display: inline-block;
}
.cta-secondary-btn:hover {
  opacity: 0.9;
}

.related-calcs-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.75rem;
  margin: 1.25rem 0 2.5rem;
}

.related-calc-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  color: var(--text-light);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  transition: border-color 0.15s ease;
}
.related-calc-btn:hover {
  border-color: var(--accent-blue);
  color: #ffffff;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 1.25rem;
  margin-bottom: 0.75rem;
}

.faq-item h3 {
  font-size: 1.05rem;
  color: #ffffff;
  margin-bottom: 0.5rem;
}

.faq-item p {
  font-size: 0.9rem;
  color: var(--text-body);
  line-height: 1.6;
}

.related-articles-list {
  list-style: none;
  padding: 0;
  margin: 1rem 0 2.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.related-articles-list a {
  color: #38bdf8;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
}
.related-articles-list a:hover {
  text-decoration: underline;
}

/* Hub Grid Styles */
.hub-header {
  text-align: center;
  margin-bottom: 3rem;
}

.tag-badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: none;
  letter-spacing: 0.02em;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  background: rgba(37, 99, 235, 0.15);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: var(--accent-blue);
  margin-bottom: 0.75rem;
}

.calculator-hero-action {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(270px, 1fr));
  gap: 1.5rem;
}

.article-hub-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease, border-color 0.2s ease;
}
.article-hub-card:hover {
  transform: translateY(-2px);
  border-color: rgba(59, 130, 246, 0.5);
}

.card-img-link {
  display: block;
  width: 100%;
  aspect-ratio: 1200 / 630;
  overflow: hidden;
  background: #070B14;
}

.card-thumb {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.card-content {
  padding: 1.25rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.card-cat {
  font-size: 0.7rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #38bdf8;
  margin-bottom: 0.5rem;
}

.card-content h2 {
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 0.5rem;
}

.card-content h2 a {
  color: #ffffff;
  text-decoration: none;
}
.card-content h2 a:hover {
  color: #60a5fa;
}

.card-content p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 1rem;
  flex: 1;
}

.card-meta {
  font-size: 0.75rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-light);
  padding-top: 0.75rem;
}