/* ============================================
   WAVELENGTH CALCULATOR - MAIN STYLESHEET
   Science/Physics - Indigo Theme
   ============================================ */

:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --primary-light: #818cf8;
  --primary-bg: #eef2ff;
  --secondary: #4338ca;
  --accent: #8b5cf6;
  --success: #10b981;
  --success-bg: #d1fae5;
  --warning: #f59e0b;
  --warning-bg: #fef3c7;
  --error: #ef4444;
  --error-bg: #fee2e2;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", Monaco, "Cascadia Code", "Roboto Mono", monospace;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: var(--font-sans); font-size: 16px; line-height: 1.6; color: var(--gray-800); background: var(--gray-50); min-height: 100vh; display: flex; flex-direction: column; }

h1, h2, h3, h4 { font-weight: 600; line-height: 1.3; color: var(--gray-900); }
h1 { font-size: 2.25rem; margin-bottom: 1rem; }
h2 { font-size: 1.5rem; margin-top: 2rem; margin-bottom: 1rem; }
h3 { font-size: 1.25rem; margin-top: 1.5rem; margin-bottom: 0.5rem; }
p { margin-bottom: 1rem; }
a { color: var(--primary-dark); text-decoration: none; transition: color 0.15s ease; }
a:hover { color: var(--primary); text-decoration: underline; }
ul, ol { margin-bottom: 1rem; padding-left: 1.5rem; }
li { margin-bottom: 0.5rem; }

.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 1rem; }
.content-narrow { max-width: 800px; margin: 0 auto; }
main { flex: 1; padding: 2rem 0 3rem; }

/* Header */
.header { background: white; border-bottom: 1px solid var(--gray-200); position: sticky; top: 0; z-index: 100; }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { display: flex; align-items: center; gap: 0.5rem; font-weight: 700; font-size: 1.125rem; color: var(--gray-900); text-decoration: none; }
.logo:hover { text-decoration: none; color: var(--primary-dark); }
.logo-icon { width: 32px; height: 32px; color: var(--primary); }
.nav-desktop { display: flex; align-items: center; gap: 1.5rem; }
.nav-desktop a { font-size: 0.9375rem; font-weight: 500; color: var(--gray-600); padding: 0.5rem 0; border-bottom: 2px solid transparent; transition: all 0.15s ease; }
.nav-desktop a:hover, .nav-desktop a.active { color: var(--primary-dark); text-decoration: none; border-bottom-color: var(--primary); }
.nav-toggle { display: none; background: none; border: none; padding: 0.5rem; cursor: pointer; color: var(--gray-700); }
.nav-toggle svg { width: 24px; height: 24px; }
.nav-mobile { display: none; position: absolute; top: 100%; left: 0; right: 0; background: white; border-bottom: 1px solid var(--gray-200); padding: 1rem; box-shadow: var(--shadow-lg); }
.nav-mobile.active { display: block; }
.nav-mobile a { display: block; padding: 0.5rem 1rem; color: var(--gray-700); font-weight: 500; border-radius: var(--radius-md); }
.nav-mobile a:hover { background: var(--gray-100); text-decoration: none; }
@media (max-width: 768px) { .nav-desktop { display: none; } .nav-toggle { display: block; } }

.intro-text { font-size: 1.125rem; color: var(--gray-600); margin-bottom: 1.5rem; max-width: 700px; }

/* Calculator Card */
.calculator-card {
  background: white;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  padding: 0;
  margin-bottom: 1.5rem;
  overflow: hidden;
  max-width: 720px;
  margin-left: auto;
  margin-right: auto;
}

/* Tabs */
.calc-tabs {
  display: flex;
  background: var(--gray-100);
  border-bottom: 1px solid var(--gray-200);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}
.calc-tabs::-webkit-scrollbar { display: none; }
.calc-tab {
  flex: 1;
  min-width: 0;
  padding: 0.75rem 0.25rem;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--gray-600);
  background: transparent;
  border: none;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  transition: all 0.15s ease;
  border-bottom: 3px solid transparent;
}
.calc-tab:hover { color: var(--gray-800); background: var(--gray-50); }
.calc-tab.active { color: var(--primary-dark); background: white; border-bottom-color: var(--primary); }
.calc-tab svg { width: 18px; height: 18px; flex-shrink: 0; }
.calc-tab-label { white-space: nowrap; font-size: 0.6875rem; }
@media (min-width: 480px) {
  .calc-tab { padding: 0.75rem 0.5rem; }
  .calc-tab-label { font-size: 0.75rem; }
  .calc-tab svg { width: 20px; height: 20px; }
}

.calc-panel { display: none; padding: 1.25rem; }
.calc-panel.active { display: block; }
@media (max-width: 480px) {
  .calc-panel { padding: 1rem; }
}

/* Form */
.form-grid { display: grid; gap: 1rem; }
.form-row { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0.75rem; }
.form-row-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.75rem; }
@media (max-width: 500px) { .form-row, .form-row-3 { grid-template-columns: 1fr; } }
.form-group { display: flex; flex-direction: column; gap: 0.25rem; }
.form-label { font-size: 0.8125rem; font-weight: 500; color: var(--gray-700); }
.form-hint { font-size: 0.6875rem; color: var(--gray-500); }

.form-input {
  width: 100%;
  height: 44px;
  padding: 0 0.75rem;
  font-size: 0.9375rem;
  font-family: var(--font-sans);
  color: var(--gray-800);
  background: white;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius-md);
  transition: all 0.15s ease;
  -webkit-appearance: none;
  appearance: none;
}
.form-input:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-bg); }
.form-input::placeholder { color: var(--gray-400); }

/* Make date inputs fully clickable */
.form-input[type="date"],
.form-input[type="time"],
.form-input[type="datetime-local"] {
  cursor: pointer;
  position: relative;
}
.form-input[type="date"]::-webkit-calendar-picker-indicator,
.form-input[type="time"]::-webkit-calendar-picker-indicator,
.form-input[type="datetime-local"]::-webkit-calendar-picker-indicator {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  width: auto;
  height: auto;
  color: transparent;
  background: transparent;
  cursor: pointer;
}

.form-select {
  height: 44px;
  padding: 0 2rem 0 0.75rem;
  font-size: 0.875rem;
  color: var(--gray-800);
  background: white url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3e%3c/svg%3e") no-repeat right 0.5rem center;
  background-size: 1.25rem;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius-md);
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}
.form-select:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-bg); }

.input-group { display: flex; gap: 0.5rem; }
.input-group .form-input { flex: 1; min-width: 0; }
.input-group .form-select { width: 90px; flex-shrink: 0; }
@media (max-width: 400px) {
  .input-group .form-select { width: 80px; font-size: 0.8125rem; }
}

/* Radio */
.radio-group { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.radio-option {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  cursor: pointer;
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius-md);
  transition: all 0.15s ease;
  font-size: 0.8125rem;
}
.radio-option:hover { border-color: var(--primary-light); background: var(--primary-bg); }
.radio-option:has(input:checked) { border-color: var(--primary); background: var(--primary-bg); }
.radio-option input[type="radio"] {
  width: 14px;
  height: 14px;
  accent-color: var(--primary);
  cursor: pointer;
  margin: 0;
}
@media (max-width: 480px) {
  .radio-group { gap: 0.375rem; }
  .radio-option { padding: 0.375rem 0.625rem; font-size: 0.75rem; }
}

/* Checkbox */
.checkbox-wrapper { display: flex; align-items: center; gap: 0.5rem; cursor: pointer; }
.checkbox-wrapper input { width: 16px; height: 16px; accent-color: var(--primary); cursor: pointer; margin: 0; }
.checkbox-label { font-size: 0.8125rem; color: var(--gray-700); }

/* Calculate Button */
.calculate-btn {
  width: 100%;
  height: 48px;
  margin-top: 1rem;
  font-size: 0.9375rem;
  font-weight: 600;
  color: white;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: all 0.15s ease;
  box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.35);
}
.calculate-btn:hover { transform: translateY(-1px); box-shadow: 0 6px 20px 0 rgba(99, 102, 241, 0.45); }
.calculate-btn:active { transform: translateY(0); }
.calculate-btn svg { width: 18px; height: 18px; }

/* Results */
.results-section {
  display: none;
  margin-top: 1.25rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--gray-200);
}
.results-section.visible { display: block; animation: fadeIn 0.25s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

/* Enhanced Results Report */
.results-report {
  max-width: 800px;
  margin: 1.5rem auto 0;
  background: white;
  border-radius: var(--radius-xl);
  border: 1px solid var(--gray-200);
  overflow: hidden;
}
.results-report-header {
  padding: 1rem 1.25rem;
  background: var(--gray-50);
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.results-report-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--gray-800);
  margin: 0;
}
.results-report-actions {
  display: flex;
  gap: 0.5rem;
}
.print-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.5rem 0.75rem;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--gray-600);
  background: white;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.15s ease;
}
.print-btn:hover { background: var(--gray-50); border-color: var(--gray-400); color: var(--gray-800); }
.print-btn svg { width: 16px; height: 16px; }
.results-report-body { padding: 1.25rem; }

/* Results Tables */
.results-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
  margin-bottom: 1rem;
}
.results-table th,
.results-table td {
  padding: 0.625rem 0.875rem;
  text-align: left;
  border-bottom: 1px solid var(--gray-200);
}
.results-table th {
  font-weight: 600;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--gray-500);
  background: var(--gray-50);
}
.results-table td { color: var(--gray-700); }
.results-table tbody tr:last-child td { border-bottom: none; }
.results-table .value-col { font-family: var(--font-mono); font-weight: 500; color: var(--gray-900); }
.results-table .highlight-row { background: var(--primary-bg); }
.results-table .highlight-row td { color: var(--primary-dark); font-weight: 600; }

/* Visual Bar Chart */
.result-bar-container {
  margin: 1rem 0;
  padding: 1rem;
  background: var(--gray-50);
  border-radius: var(--radius-lg);
}
.result-bar-label {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--gray-600);
  margin-bottom: 0.5rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}
.result-bar {
  height: 40px;
  background: var(--gray-200);
  border-radius: var(--radius-md);
  overflow: hidden;
  position: relative;
}
.result-bar-fill {
  height: 100%;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: flex-end;
  padding-right: 0.75rem;
  font-size: 0.8125rem;
  font-weight: 600;
  color: white;
  min-width: 60px;
  transition: width 0.5s ease;
}
.result-bar-fill.gradient-em { background: linear-gradient(90deg, #7c3aed, #6366f1, #3b82f6, #10b981, #eab308, #f97316, #ef4444); }
.result-bar-fill.gradient-sound { background: linear-gradient(90deg, var(--primary), var(--primary-dark)); }
.result-bar-fill.gradient-antenna { background: linear-gradient(90deg, var(--accent), var(--primary)); }
.result-bar-markers {
  display: flex;
  justify-content: space-between;
  margin-top: 0.25rem;
  font-size: 0.6875rem;
  color: var(--gray-500);
}

/* Tips Grid */
.tips-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
  margin-top: 1rem;
}
@media (max-width: 600px) { .tips-grid { grid-template-columns: 1fr; } }
.tip-item {
  display: flex;
  gap: 0.75rem;
  padding: 0.875rem;
  background: var(--gray-50);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--primary-light);
}
.tip-icon {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-bg);
  border-radius: var(--radius-md);
  color: var(--primary);
}
.tip-icon svg { width: 18px; height: 18px; }
.tip-content { flex: 1; min-width: 0; }
.tip-title { font-size: 0.8125rem; font-weight: 600; color: var(--gray-800); margin-bottom: 0.125rem; }
.tip-text { font-size: 0.75rem; color: var(--gray-600); line-height: 1.4; }

/* What This Means Section */
.meaning-section {
  margin-top: 1rem;
  padding: 1rem;
  background: linear-gradient(135deg, var(--success-bg) 0%, #a7f3d0 100%);
  border-radius: var(--radius-lg);
  border-left: 4px solid var(--success);
}
.meaning-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: #065f46;
  margin: 0 0 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.meaning-title svg { width: 18px; height: 18px; }
.meaning-text { font-size: 0.8125rem; color: #047857; line-height: 1.5; margin: 0; }
.meaning-text p { margin: 0 0 0.5rem; }
.meaning-text p:last-child { margin: 0; }

/* Formula Display */
.formula-display {
  margin-top: 1rem;
  padding: 0.875rem 1rem;
  background: var(--gray-900);
  border-radius: var(--radius-md);
}
.formula-display-title {
  font-size: 0.6875rem;
  font-weight: 500;
  color: var(--gray-400);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}
.formula-display-content {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--primary-light);
  line-height: 1.6;
}

/* Status Indicators */
.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.25rem 0.5rem;
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  border-radius: var(--radius-full);
}
.status-badge.status-info { background: var(--primary-bg); color: var(--primary-dark); }
.status-badge.status-success { background: var(--success-bg); color: #047857; }
.status-badge.status-warning { background: var(--warning-bg); color: #b45309; }
.status-badge.status-error { background: var(--error-bg); color: #dc2626; }

/* Section Divider */
.results-divider {
  margin: 1.25rem 0;
  border: none;
  border-top: 1px solid var(--gray-200);
}
.results-section-title {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--gray-700);
  margin: 1rem 0 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

/* Print Styles */
@media print {
  .header, .footer, .calc-tabs, .calculate-btn, .print-btn, .nav-desktop, .nav-mobile { display: none !important; }
  .calculator-card { box-shadow: none; border: 1px solid var(--gray-300); max-width: 100%; }
  .results-section, .results-report { display: block !important; }
  .calc-panel { display: none !important; }
  .calc-panel.active { display: block !important; }
  body { background: white; }
  .results-report { border: 1px solid var(--gray-300); box-shadow: none; }
}

.result-primary {
  text-align: center;
  padding: 1.25rem;
  margin-bottom: 0.75rem;
  background: linear-gradient(135deg, var(--primary-bg) 0%, #e0e7ff 100%);
  border-radius: var(--radius-lg);
  border: 2px solid var(--primary-light);
}
.result-label {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--gray-500);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.375rem;
}
.result-value {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--primary-dark);
  line-height: 1.2;
  font-family: var(--font-mono);
  word-break: break-word;
}
.result-sublabel {
  font-size: 0.8125rem;
  color: var(--gray-600);
  margin-top: 0.375rem;
  font-family: var(--font-mono);
}
.result-description { font-size: 0.875rem; color: var(--gray-700); margin-top: 0.5rem; }

/* Multi-unit Results */
.result-units { display: flex; flex-wrap: wrap; gap: 0.375rem; justify-content: center; margin-top: 0.5rem; }
.result-unit {
  padding: 0.25rem 0.5rem;
  background: white;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--gray-700);
  border: 1px solid var(--gray-200);
}

/* Color Swatch */
.color-swatch {
  width: 100%;
  height: 40px;
  border-radius: var(--radius-md);
  margin-top: 0.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.875rem;
  color: white;
  text-shadow: 0 1px 2px rgba(0,0,0,0.3);
}

/* EM Spectrum */
.em-spectrum { margin-top: 1.25rem; }
.em-spectrum-title { font-size: 0.75rem; font-weight: 500; color: var(--gray-600); margin-bottom: 0.375rem; text-align: center; }
.em-spectrum-bar { display: flex; height: 28px; border-radius: var(--radius-md); overflow: hidden; position: relative; }
.em-band { flex: 1; display: flex; align-items: center; justify-content: center; font-size: 0.5625rem; font-weight: 600; color: white; text-shadow: 0 1px 1px rgba(0,0,0,0.3); }
.em-band.gamma { background: #7c3aed; }
.em-band.xray { background: #6366f1; }
.em-band.uv { background: #8b5cf6; }
.em-band.visible { background: linear-gradient(90deg, #8b5cf6, #3b82f6, #10b981, #eab308, #f97316, #ef4444); }
.em-band.ir { background: #dc2626; }
.em-band.micro { background: #b91c1c; }
.em-band.radio { background: #7f1d1d; }
.em-marker { position: absolute; top: -8px; transform: translateX(-50%); font-size: 1rem; }
.em-marker-label { position: absolute; top: 34px; transform: translateX(-50%); font-size: 0.625rem; color: var(--gray-600); white-space: nowrap; }

/* Wave Visualizer */
.wave-visualizer { margin-top: 1.25rem; padding: 0.75rem; background: var(--gray-900); border-radius: var(--radius-md); }
.wave-canvas { width: 100%; height: 80px; }
.wave-labels { display: flex; justify-content: space-between; margin-top: 0.375rem; font-size: 0.6875rem; color: var(--gray-400); }

/* Formula Box (inside calculator) */
.calc-panel .formula-box { background: var(--gray-900); padding: 0.75rem 1rem; border-radius: var(--radius-md); margin: 0 0 1rem 0; text-align: center; }
.calc-panel .formula { font-family: var(--font-mono); font-size: 1rem; color: var(--primary-light); }
.calc-panel .formula-description { font-size: 0.75rem; color: var(--gray-400); margin-top: 0.25rem; }

/* Formula Box (in content sections) */
.content-section .formula-box { background: var(--gray-900); padding: 1rem 1.5rem; border-radius: var(--radius-lg); margin: 1rem 0; text-align: center; }
.content-section .formula { font-family: var(--font-mono); font-size: 1.125rem; color: var(--primary-light); }
.content-section .formula-description { font-size: 0.8125rem; color: var(--gray-400); margin-top: 0.5rem; }

/* Results Grid */
.results-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.5rem; margin-top: 0.75rem; }
@media (max-width: 480px) { .results-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 360px) { .results-grid { grid-template-columns: 1fr; } }
.result-item { padding: 0.625rem; background: var(--gray-50); border-radius: var(--radius-md); text-align: center; }
.result-item-label { font-size: 0.6875rem; color: var(--gray-500); margin-bottom: 0.125rem; }
.result-item-value { font-size: 0.875rem; font-weight: 600; color: var(--gray-800); font-family: var(--font-mono); word-break: break-word; }

/* Content Section */
.content-section { background: white; border-radius: var(--radius-xl); box-shadow: var(--shadow-md); padding: 1.5rem; margin-bottom: 1.5rem; max-width: 800px; margin-left: auto; margin-right: auto; }
.content-section h2 { margin-top: 0; }
.content-section h2::after { content: ''; display: block; width: 60px; height: 3px; background: var(--primary); margin-top: 0.5rem; border-radius: var(--radius-full); }

/* Tables */
.table-responsive { overflow-x: auto; margin: 1.5rem 0; }
.data-table { width: 100%; border-collapse: collapse; font-size: 0.875rem; }
.data-table th, .data-table td { padding: 0.625rem 0.875rem; text-align: left; border-bottom: 1px solid var(--gray-200); }
.data-table th { font-weight: 600; color: var(--gray-700); background: var(--gray-50); }
.data-table td { color: var(--gray-600); }
.data-table tbody tr:hover { background: var(--gray-50); }
.data-table code { font-family: var(--font-mono); background: var(--gray-100); padding: 0.125rem 0.375rem; border-radius: var(--radius-sm); font-size: 0.8125rem; }

/* FAQ */
.faq-list { display: flex; flex-direction: column; gap: 0.75rem; max-width: 800px; margin-left: auto; margin-right: auto; }
.faq-item { border: 1px solid var(--gray-200); border-radius: var(--radius-lg); overflow: hidden; }
.faq-question { width: 100%; padding: 1rem; display: flex; align-items: center; justify-content: space-between; gap: 1rem; font-size: 0.9375rem; font-weight: 500; text-align: left; color: var(--gray-800); background: var(--gray-50); border: none; cursor: pointer; }
.faq-question:hover { background: var(--gray-100); }
.faq-question svg { width: 18px; height: 18px; color: var(--gray-400); transition: transform 0.15s ease; flex-shrink: 0; }
.faq-item.open .faq-question svg { transform: rotate(180deg); }
.faq-answer { display: none; padding: 1rem; background: white; }
.faq-item.open .faq-answer { display: block; }
.faq-answer p:last-child { margin-bottom: 0; }

/* Blog */
.blog-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1.5rem; margin-top: 2rem; max-width: 800px; margin-left: auto; margin-right: auto; }
.blog-card { background: white; border-radius: var(--radius-lg); box-shadow: var(--shadow-md); overflow: hidden; transition: all 0.15s ease; }
.blog-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.blog-card-content { padding: 1.25rem; }
.blog-card-meta { font-size: 0.75rem; color: var(--gray-500); margin-bottom: 0.5rem; }
.blog-card h3 { margin: 0 0 0.5rem; font-size: 1.0625rem; }
.blog-card h3 a { color: var(--gray-900); }
.blog-card h3 a:hover { color: var(--primary-dark); text-decoration: none; }
.blog-card p { font-size: 0.875rem; color: var(--gray-600); margin-bottom: 0; }

/* Footer */
.footer { background: var(--gray-900); color: var(--gray-400); padding: 2.5rem 0 1.5rem; margin-top: auto; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 2rem; margin-bottom: 2rem; }
@media (max-width: 768px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 480px) { .footer-grid { grid-template-columns: 1fr; } }
.footer-brand .logo { color: white; margin-bottom: 1rem; }
.footer-brand .logo-icon { color: var(--primary-light); }
.footer-brand p { font-size: 0.875rem; line-height: 1.6; }
.footer-nav h4 { color: white; font-size: 0.8125rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 1rem; }
.footer-nav ul { list-style: none; }
.footer-nav li { margin-bottom: 0.5rem; }
.footer-nav a { font-size: 0.875rem; color: var(--gray-400); }
.footer-nav a:hover { color: white; text-decoration: none; }
.footer-bottom { padding-top: 1.5rem; border-top: 1px solid var(--gray-800); font-size: 0.8125rem; }

/* Callout Box */
.callout-box { max-width: 800px; margin-left: auto; margin-right: auto; }

/* Utilities */
.text-center { text-align: center; }
.mt-1 { margin-top: 1rem; }
.font-mono { font-family: var(--font-mono); }

/* Responsive adjustments for enhanced results */
@media (max-width: 600px) {
  .results-report-header { flex-direction: column; align-items: flex-start; gap: 0.75rem; }
  .results-table th, .results-table td { padding: 0.5rem; font-size: 0.8125rem; }
  .result-bar-markers { font-size: 0.625rem; }
  .meaning-section { padding: 0.875rem; }
  .formula-display { padding: 0.75rem; }
  .formula-display-content { font-size: 0.8125rem; }
}