/* BU ProTool SEO Pages - Professional Design */
/* Clean, modern, minimalist, business-oriented */

/* ===== CSS Variables ===== */
:root {
  --primary-color: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #3b82f6;
  --text-color: #1f2937;
  --text-light: #6b7280;
  --text-lighter: #9ca3af;
  --bg-color: #ffffff;
  --bg-secondary: #f9fafb;
  --border-color: #e5e7eb;
  --success-color: #10b981;
  --warning-color: #f59e0b;
  --danger-color: #ef4444;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --line-height: 1.6;
  --max-width: 1100px;
  --spacing-unit: 1rem;
}

/* ===== Reset & Base ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-family);
  font-size: 16px;
  line-height: var(--line-height);
  color: var(--text-color);
  background-color: var(--bg-color);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ===== Header ===== */
.seo-header {
  background-color: var(--bg-color);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.seo-header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.seo-logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.seo-logo:hover {
  color: var(--primary-dark);
}

.seo-tagline {
  font-size: 0.875rem;
  color: var(--text-light);
  font-weight: 400;
  margin-left: 0.5rem;
}

/* ===== Breadcrumb ===== */
.breadcrumb {
  max-width: var(--max-width);
  margin: 1.5rem auto 1rem;
  padding: 0 1.5rem;
  font-size: 0.875rem;
  color: var(--text-light);
}

.breadcrumb a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color 0.2s ease;
}

.breadcrumb a:hover {
  color: var(--primary-dark);
  text-decoration: underline;
}

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

.breadcrumb .current {
  color: var(--text-color);
  font-weight: 500;
}

/* ===== Main Content ===== */
.seo-content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem 3rem;
}

/* ===== Article ===== */
article {
  background-color: var(--bg-color);
}

/* ===== Headings ===== */
h1 {
  font-size: 2.25rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-color);
  margin-bottom: 1.5rem;
  letter-spacing: -0.025em;
}

h2 {
  font-size: 1.75rem;
  font-weight: 600;
  line-height: 1.3;
  color: var(--text-color);
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  letter-spacing: -0.025em;
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 0.5rem;
}

h3 {
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text-color);
  margin-top: 1.5rem;
  margin-bottom: 0.75rem;
  letter-spacing: -0.025em;
}

/* ===== Paragraphs ===== */
p {
  margin-bottom: 1rem;
  color: var(--text-color);
}

/* ===== Links ===== */
a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color 0.2s ease, text-decoration 0.2s ease;
}

a:hover {
  color: var(--primary-dark);
  text-decoration: underline;
}

/* ===== Lists ===== */
ul, ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.5rem;
  line-height: 1.6;
}

/* ===== CTA Card ===== */
.cta-card {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  border-radius: 12px;
  padding: 2rem;
  margin: 2rem 0;
  text-align: center;
  box-shadow: var(--shadow-lg);
  color: white;
}

.cta-card h3 {
  color: white;
  font-size: 1.5rem;
  margin-top: 0;
  margin-bottom: 1rem;
  border-bottom: none;
  padding-bottom: 0;
}

.cta-card p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.125rem;
  margin-bottom: 1.5rem;
}

.cta-button {
  display: inline-block;
  background-color: white;
  color: var(--primary-color);
  padding: 0.875rem 2rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  transition: all 0.2s ease;
  box-shadow: var(--shadow-md);
}

.cta-button:hover {
  background-color: var(--bg-secondary);
  color: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  text-decoration: none;
}

/* ===== Formula Card ===== */
.formula-card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--primary-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin: 1.5rem 0;
  font-family: 'Courier New', monospace;
  font-size: 1.125rem;
  line-height: 1.8;
  box-shadow: var(--shadow-sm);
}

.formula-card .formula-label {
  font-weight: 600;
  color: var(--primary-color);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
  display: block;
  font-family: var(--font-family);
}

/* ===== Example Card ===== */
.example-card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin: 1.5rem 0;
  box-shadow: var(--shadow-sm);
}

.example-card .example-label {
  font-weight: 600;
  color: var(--text-color);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
  display: block;
}

/* ===== Tables ===== */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  background-color: var(--bg-color);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

thead {
  background-color: var(--bg-secondary);
  border-bottom: 2px solid var(--border-color);
}

th {
  padding: 1rem;
  text-align: left;
  font-weight: 600;
  color: var(--text-color);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

td {
  padding: 1rem;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-color);
}

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

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

/* ===== FAQ Section ===== */
.faq-section {
  margin-top: 2rem;
}

.faq-section h2 {
  margin-top: 0;
}

.faq-item {
  margin-bottom: 1rem;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  overflow: hidden;
  background-color: var(--bg-color);
  box-shadow: var(--shadow-sm);
}

.faq-question {
  padding: 1rem 1.5rem;
  background-color: var(--bg-secondary);
  font-weight: 600;
  color: var(--text-color);
  margin: 0;
  border-bottom: 1px solid var(--border-color);
}

.faq-answer {
  padding: 1rem 1.5rem;
  margin: 0;
  color: var(--text-color);
}

/* ===== Related Links ===== */
.related-links {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin: 2rem 0;
  box-shadow: var(--shadow-sm);
}

.related-links h3 {
  margin-top: 0;
  margin-bottom: 1rem;
  font-size: 1.125rem;
}

.related-links ul {
  margin-bottom: 0;
  padding-left: 1.25rem;
}

.related-links li {
  margin-bottom: 0.75rem;
}

.related-links a {
  color: var(--primary-color);
  font-weight: 500;
}

/* ===== Footer ===== */
.seo-footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 2rem 0;
  margin-top: 3rem;
}

.seo-footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  text-align: center;
}

.seo-footer small {
  color: var(--text-light);
  font-size: 0.875rem;
  line-height: 1.5;
}

/* ===== Disclaimer ===== */
.disclaimer {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1rem 1.5rem;
  margin: 2rem 0;
  font-size: 0.875rem;
  color: var(--text-light);
  box-shadow: var(--shadow-sm);
}

/* ===== Strong/Emphasis ===== */
strong {
  font-weight: 600;
  color: var(--text-color);
}

/* ===== Code/Inline ===== */
code {
  background-color: var(--bg-secondary);
  padding: 0.125rem 0.375rem;
  border-radius: 4px;
  font-family: 'Courier New', monospace;
  font-size: 0.875rem;
  color: var(--primary-color);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  :root {
    --max-width: 100%;
  }

  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  h3 {
    font-size: 1.125rem;
  }

  .seo-header-inner {
    flex-direction: column;
    gap: 0.5rem;
    text-align: center;
  }

  .seo-tagline {
    margin-left: 0;
  }

  .breadcrumb {
    font-size: 0.8125rem;
  }

  .seo-content {
    padding: 0 1rem 2rem;
  }

  .cta-card {
    padding: 1.5rem;
  }

  .cta-card h3 {
    font-size: 1.25rem;
  }

  .cta-card p {
    font-size: 1rem;
  }

  table {
    font-size: 0.875rem;
  }

  th, td {
    padding: 0.75rem 0.5rem;
  }

  /* Horizontal scroll for tables on mobile */
  table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: 1.5rem;
  }

  h2 {
    font-size: 1.25rem;
  }

  .cta-button {
    width: 100%;
    text-align: center;
  }
}

/* ===== Print Styles ===== */
@media print {
  .seo-header,
  .breadcrumb,
  .cta-card,
  .seo-footer {
    display: none;
  }

  body {
    background-color: white;
    color: black;
  }

  a {
    color: black;
    text-decoration: underline;
  }
}

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

/* Focus styles for keyboard navigation */
a:focus,
button:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* ===== Skip Link ===== */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--primary-color);
  color: white;
  padding: 8px;
  z-index: 100;
  transition: top 0.3s;
}

.skip-link:focus {
  top: 0;
}