/* ============================================
   VOLTAGE DROP CALCULATOR - MAIN STYLESHEET
   Tech/Science Category - Cyan Theme
   ============================================ */

:root {
  --primary: #06b6d4;
  --primary-dark: #0891b2;
  --primary-light: #22d3ee;
  --primary-bg: #ecfeff;
  --secondary: #0e7490;
  --accent: #f59e0b;
  --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);
  --shadow-xl: 0 20px 25px -5px 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, h5, h6 { 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; padding-bottom: 0.5rem; border-bottom: 2px solid var(--primary-bg); }
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; }
strong { font-weight: 600; }

.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 1rem; }
.content-narrow { max-width: 900px; 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; } }

/* Calculator Page Title & Intro */
.calc-page-title { text-align: center; margin-bottom: 0.75rem; }
.intro-text { font-size: 1rem; color: var(--gray-600); margin-bottom: 2rem; max-width: 900px; margin-left: auto; margin-right: auto; text-align: center; }

/* Calculator Card */
.calculator-card {
  background: white;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  padding: 1.5rem;
  margin-bottom: 2rem;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}
@media (max-width: 940px) {
  .calculator-card {
    max-width: 100%;
    padding: 1.25rem;
    border-radius: var(--radius-lg);
  }
}

/* Calculator Settings Bar */
.calc-settings-bar { display: flex; justify-content: space-between; align-items: flex-end; gap: 1.25rem; padding-bottom: 1.25rem; margin-bottom: 1.5rem; border-bottom: 1px solid var(--gray-200); flex-wrap: wrap; }
.calc-setting-group { display: flex; flex-direction: column; gap: 0.5rem; }
.calc-setting-label { display: flex; align-items: center; gap: 0.5rem; font-size: 0.8125rem; font-weight: 600; color: var(--gray-500); text-transform: uppercase; letter-spacing: 0.03em; }
.calc-setting-label svg { color: var(--primary); }
.calc-setting-select { min-width: 200px; height: 44px; padding: 0 2.5rem 0 1rem; font-size: 0.9375rem; font-weight: 500; font-family: var(--font-sans); color: var(--gray-800); background: var(--gray-50); border: 2px solid var(--gray-200); border-radius: var(--radius-lg); cursor: pointer; appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 12px center; transition: all 0.15s ease; }
.calc-setting-select:focus { outline: none; border-color: var(--primary); background-color: white; box-shadow: 0 0 0 3px var(--primary-bg); }
.calc-setting-select:hover { border-color: var(--gray-300); background-color: white; }

/* Unit Toggle */
.unit-toggle-switch { position: relative; width: 140px; height: 44px; background: var(--gray-100); border: 2px solid var(--gray-200); border-radius: var(--radius-lg); padding: 3px; cursor: pointer; transition: all 0.15s ease; }
.unit-toggle-switch:hover { border-color: var(--gray-300); }
.unit-toggle-slider { position: absolute; width: calc(50% - 3px); height: calc(100% - 6px); background: white; border-radius: var(--radius-md); box-shadow: var(--shadow-sm); transition: transform 0.2s ease; }
.unit-toggle-switch[data-unit="metric"] .unit-toggle-slider { transform: translateX(100%); }
.unit-toggle-labels { position: relative; display: flex; height: 100%; }
.unit-toggle-label { flex: 1; display: flex; align-items: center; justify-content: center; font-size: 0.8125rem; font-weight: 600; color: var(--gray-400); z-index: 1; transition: color 0.15s ease; }
.unit-toggle-label.active { color: var(--gray-800); }

/* Calculator Form */
.calc-form { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; }
@media (max-width: 640px) {
  .calc-form { grid-template-columns: 1fr; gap: 1.25rem; }
}
@media (max-width: 480px) {
  .calc-settings-bar { flex-direction: column; align-items: stretch; gap: 0.75rem; }
  .calc-setting-select { width: 100%; min-width: auto; }
  .unit-toggle-switch { width: 100%; }
  .calc-material-toggle { grid-template-columns: 1fr; }
}

.calc-section { display: flex; flex-direction: column; gap: 1.25rem; }
.calc-section-header { display: flex; align-items: center; gap: 0.5rem; padding-bottom: 0.625rem; border-bottom: 2px solid var(--primary-bg); font-size: 0.8125rem; font-weight: 600; color: var(--gray-700); text-transform: uppercase; letter-spacing: 0.03em; }
.calc-section-header svg { width: 18px; height: 18px; color: var(--primary); }

/* Calculator Fields */
.calc-field { display: flex; flex-direction: column; gap: 0.5rem; }
.calc-field-header { display: flex; justify-content: space-between; align-items: center; }
.calc-field-label { font-size: 0.9375rem; font-weight: 500; color: var(--gray-700); }
.calc-field-hint { font-weight: 400; color: var(--gray-400); font-size: 0.8125rem; }
.calc-field-value { display: flex; align-items: center; gap: 0.375rem; }
.calc-number-input { width: 80px; height: 36px; padding: 0 0.5rem; font-size: 1rem; font-weight: 600; font-family: var(--font-mono); text-align: right; color: var(--primary-dark); background: var(--primary-bg); border: 2px solid transparent; border-radius: var(--radius-md); transition: all 0.15s ease; }
.calc-number-input:focus { outline: none; border-color: var(--primary); background: white; }
.calc-field-unit { font-size: 0.875rem; font-weight: 600; color: var(--gray-500); min-width: 24px; }

/* Calculator Slider */
.calc-slider { width: 100%; height: 8px; background: var(--gray-200); border-radius: var(--radius-full); appearance: none; cursor: pointer; margin-top: 0.375rem; }
.calc-slider::-webkit-slider-runnable-track { height: 8px; background: var(--gray-200); border-radius: var(--radius-full); }
.calc-slider::-webkit-slider-thumb { appearance: none; width: 22px; height: 22px; background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%); border-radius: 50%; cursor: pointer; box-shadow: 0 2px 8px rgba(6, 182, 212, 0.4); transition: transform 0.1s ease, box-shadow 0.1s ease; margin-top: -7px; border: 3px solid white; }
.calc-slider::-webkit-slider-thumb:hover { transform: scale(1.15); box-shadow: 0 3px 12px rgba(6, 182, 212, 0.5); }
.calc-slider::-moz-range-track { height: 8px; background: var(--gray-200); border-radius: var(--radius-full); }
.calc-slider::-moz-range-thumb { width: 20px; height: 20px; background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%); border: 3px solid white; border-radius: 50%; cursor: pointer; }
.calc-slider:focus { outline: none; }
.calc-slider:focus::-webkit-slider-thumb { box-shadow: 0 0 0 4px var(--primary-bg), 0 2px 8px rgba(6, 182, 212, 0.4); }
.calc-slider-hints { display: flex; justify-content: space-between; font-size: 0.75rem; color: var(--gray-400); margin-top: 0.375rem; }

/* Calculator Select */
.calc-select { width: 100%; height: 48px; padding: 0 2.5rem 0 1rem; font-size: 0.9375rem; font-family: var(--font-sans); color: var(--gray-800); background: var(--gray-50); border: 2px solid var(--gray-200); border-radius: var(--radius-md); cursor: pointer; appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 12px center; transition: all 0.15s ease; }
.calc-select:focus { outline: none; border-color: var(--primary); background-color: white; box-shadow: 0 0 0 3px var(--primary-bg); }
.calc-select:hover { border-color: var(--gray-300); background-color: white; }

/* Material Toggle Cards */
.calc-material-toggle { display: grid; grid-template-columns: 1fr 1fr; gap: 0.75rem; }
.calc-material-option { cursor: pointer; }
.calc-material-option input { position: absolute; opacity: 0; pointer-events: none; }
.calc-material-card { display: flex; align-items: center; gap: 0.75rem; padding: 0.875rem 1rem; background: var(--gray-50); border: 2px solid var(--gray-200); border-radius: var(--radius-lg); transition: all 0.15s ease; }
.calc-material-option input:checked + .calc-material-card { background: var(--primary-bg); border-color: var(--primary); }
.calc-material-option:hover .calc-material-card { border-color: var(--gray-300); }
.calc-material-option input:checked + .calc-material-card:hover { border-color: var(--primary); }
.calc-material-icon { width: 32px; height: 32px; border-radius: 50%; flex-shrink: 0; }
.calc-material-icon.copper { background: linear-gradient(135deg, #b87333 0%, #da8a67 100%); }
.calc-material-icon.aluminum { background: linear-gradient(135deg, #a8a9ad 0%, #d4d5d9 100%); }
.calc-material-info { display: flex; flex-direction: column; gap: 0.125rem; min-width: 0; }
.calc-material-name { font-size: 0.9375rem; font-weight: 600; color: var(--gray-800); }
.calc-material-desc { font-size: 0.75rem; color: var(--gray-500); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
@media (max-width: 480px) {
  .calc-material-toggle { grid-template-columns: 1fr; }
}

/* AC-only */
.ac-only { display: none; }
.ac-only.visible { display: flex; }

/* Legacy Form Styles (for compatibility) */
.form-grid { display: grid; gap: 1rem; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 0.75rem; }
@media (max-width: 600px) { .form-row { grid-template-columns: 1fr; } }
.form-group { display: flex; flex-direction: column; gap: 0.25rem; }
.form-label { font-size: 0.875rem; font-weight: 500; color: var(--gray-700); }
.form-label-hint { font-weight: 400; color: var(--gray-500); }
.form-input { width: 100%; height: 44px; padding: 0 0.875rem; 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; cursor: text; }
.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); }
.form-select { width: 100%; height: 44px; padding: 0 2.5rem 0 0.875rem; 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); cursor: pointer; appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 10px center; transition: all 0.15s ease; }
.form-select:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-bg); }
.radio-group { display: flex; gap: 1rem; }
.radio-option { display: flex; align-items: center; gap: 0.5rem; cursor: pointer; }
.radio-option input { width: 18px; height: 18px; accent-color: var(--primary); cursor: pointer; }
.radio-option span { font-size: 0.875rem; color: var(--gray-700); }

/* Calculate Button */
.calculate-btn { width: 100%; height: 52px; margin-top: 1.5rem; font-size: 1.0625rem; font-weight: 600; color: white; background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%); border: none; border-radius: var(--radius-lg); cursor: pointer; display: flex; align-items: center; justify-content: center; gap: 0.625rem; transition: all 0.15s ease; box-shadow: 0 4px 14px 0 rgba(6, 182, 212, 0.4); }
.calculate-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 20px 0 rgba(6, 182, 212, 0.5); }
.calculate-btn:active { transform: translateY(0); }
.calculate-btn svg { width: 22px; height: 22px; }
@media (max-width: 640px) {
  .calculate-btn { height: 48px; font-size: 1rem; }
  .calculate-btn svg { width: 20px; height: 20px; }
}

/* Results */
.results-section { display: none; margin-bottom: 2rem; max-width: 900px; margin-left: auto; margin-right: auto; }
.results-section.visible { display: block; animation: fadeIn 0.3s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
.results-card { background: white; border-radius: var(--radius-xl); border: 1px solid var(--gray-200); box-shadow: var(--shadow-md); padding: 1.5rem; }
@media (max-width: 768px) {
  .results-section { max-width: 100%; }
  .results-card { border-radius: var(--radius-lg); padding: 1.25rem; }
}
.results-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 1rem; flex-wrap: wrap; gap: 0.75rem; }
.results-title { font-size: 1.125rem; font-weight: 600; color: var(--gray-800); margin: 0; }
.results-actions { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.action-btn { display: flex; align-items: center; gap: 0.375rem; padding: 0.5rem 0.875rem; font-size: 0.8125rem; font-weight: 500; color: var(--gray-600); background: var(--gray-100); border: none; border-radius: var(--radius-md); cursor: pointer; transition: all 0.15s ease; }
.action-btn:hover { background: var(--gray-200); color: var(--gray-800); }
.action-btn svg { width: 16px; height: 16px; }

/* Primary Result */
.result-primary { text-align: center; padding: 1.5rem; margin-bottom: 0; background: var(--gray-50); border-radius: var(--radius-lg); }
.result-primary.success { background: var(--success-bg); }
.result-primary.warning { background: var(--warning-bg); }
.result-primary.error { background: var(--error-bg); }
.result-label { font-size: 0.8125rem; font-weight: 500; color: var(--gray-500); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 0.5rem; }
.result-value { font-size: 3rem; font-weight: 700; font-family: var(--font-mono); color: var(--gray-900); line-height: 1.2; }
.result-primary.success .result-value { color: var(--success); }
.result-primary.warning .result-value { color: var(--warning); }
.result-primary.error .result-value { color: var(--error); }
.result-percentage { font-size: 1.5rem; font-weight: 600; color: var(--gray-600); margin-top: 0.25rem; }
.result-status { display: inline-flex; align-items: center; gap: 0.375rem; margin-top: 0.75rem; padding: 0.375rem 1rem; font-size: 0.875rem; font-weight: 600; border-radius: var(--radius-full); }
.result-status.success { color: var(--success); background: white; }
.result-status.warning { color: #b45309; background: white; }
.result-status.error { color: var(--error); background: white; }
.result-status svg { width: 16px; height: 16px; }
@media (max-width: 480px) {
  .result-value { font-size: 2.25rem; }
  .result-percentage { font-size: 1.25rem; }
}

/* Results Grid */
.results-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.75rem; margin-bottom: 1.5rem; }
@media (max-width: 500px) { .results-grid { grid-template-columns: 1fr 1fr; } }
.result-item { padding: 1rem; background: var(--gray-50); border-radius: var(--radius-md); text-align: center; }
.result-item-label { font-size: 0.75rem; color: var(--gray-500); margin-bottom: 0.25rem; text-transform: uppercase; letter-spacing: 0.03em; }
.result-item-value { font-size: 1.25rem; font-weight: 600; font-family: var(--font-mono); color: var(--gray-800); }

/* Recommendation */
.result-recommendation { padding: 1rem 1.25rem; background: var(--primary-bg); border-radius: var(--radius-md); border-left: 4px solid var(--primary); }
.result-recommendation p { margin: 0; font-size: 0.9375rem; color: var(--gray-700); line-height: 1.6; }
.result-recommendation strong { color: var(--gray-900); font-weight: 600; }

/* Visualization */
.visualization-section { display: none; margin-bottom: 2rem; max-width: 900px; margin-left: auto; margin-right: auto; }
.visualization-section.visible { display: block; }
.visualization-card { background: white; border-radius: var(--radius-xl); border: 1px solid var(--gray-200); box-shadow: var(--shadow-md); padding: 1.5rem; }
.visualization-title { font-size: 1rem; font-weight: 600; color: var(--gray-700); margin-bottom: 1rem; }
@media (max-width: 768px) {
  .visualization-section { max-width: 100%; }
  .visualization-card { border-radius: var(--radius-lg); padding: 1.25rem; }
}

/* Circuit Diagram */
.circuit-diagram { display: flex; align-items: center; justify-content: space-between; padding: 1rem; margin-bottom: 1rem; background: var(--gray-50); border-radius: var(--radius-lg); }
.circuit-node { display: flex; flex-direction: column; align-items: center; gap: 0.125rem; }
.circuit-node-icon { width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; background: white; border: 2px solid var(--gray-300); border-radius: 50%; }
.circuit-node-icon svg { width: 20px; height: 20px; color: var(--gray-600); }
.circuit-node-label { font-size: 0.6875rem; font-weight: 500; color: var(--gray-500); text-transform: uppercase; }
.circuit-node-value { font-size: 1rem; font-weight: 600; font-family: var(--font-mono); color: var(--gray-800); }
.circuit-wire { flex: 1; height: 4px; margin: 0 0.75rem; background: var(--gray-300); position: relative; }
.circuit-wire::after { content: attr(data-resistance); position: absolute; top: -20px; left: 50%; transform: translateX(-50%); font-size: 0.6875rem; color: var(--gray-500); white-space: nowrap; }
.circuit-wire.low-drop { background: var(--success); }
.circuit-wire.medium-drop { background: var(--warning); }
.circuit-wire.high-drop { background: var(--error); }

/* Voltage Bar */
.voltage-bar-container { margin-bottom: 0.75rem; }
.voltage-bar-label { display: flex; justify-content: space-between; margin-bottom: 0.25rem; font-size: 0.75rem; color: var(--gray-500); }
.voltage-bar { height: 20px; background: var(--gray-200); border-radius: var(--radius-md); position: relative; overflow: hidden; }
.voltage-bar-fill { height: 100%; border-radius: var(--radius-md); transition: width 0.25s ease; }
.voltage-bar-fill.success { background: linear-gradient(90deg, var(--success) 0%, #34d399 100%); }
.voltage-bar-fill.warning { background: linear-gradient(90deg, var(--warning) 0%, #fbbf24 100%); }
.voltage-bar-fill.error { background: linear-gradient(90deg, var(--error) 0%, #f87171 100%); }
.voltage-bar-markers { position: absolute; top: 0; left: 0; right: 0; bottom: 0; }
.voltage-bar-marker { position: absolute; top: 0; bottom: 0; width: 2px; background: var(--gray-400); }
.voltage-bar-marker::after { content: attr(data-label); position: absolute; bottom: -18px; left: 50%; transform: translateX(-50%); font-size: 0.625rem; color: var(--gray-500); white-space: nowrap; }
.voltage-bar-marker[data-percent="3"] { left: 30%; }
.voltage-bar-marker[data-percent="5"] { left: 50%; }

/* Chart */
.chart-container { height: 200px; margin-top: 1rem; }

/* Content Sections */
.content-section { background: white; border-radius: var(--radius-xl); border: 1px solid var(--gray-200); box-shadow: var(--shadow-sm); padding: 1.5rem; margin-bottom: 1.5rem; max-width: 900px; margin-left: auto; margin-right: auto; }
.content-section h2 { margin-top: 0; border-bottom: none; padding-bottom: 0; }
.content-section h2::after { content: ''; display: block; width: 60px; height: 3px; background: var(--primary); margin-top: 0.5rem; border-radius: var(--radius-full); }
@media (max-width: 768px) {
  .content-section { padding: 1.25rem; border-radius: var(--radius-lg); }
}

/* Meta */
.meta-info { display: flex; align-items: center; gap: 1.5rem; margin-bottom: 1.5rem; padding-bottom: 1rem; border-bottom: 1px solid var(--gray-200); font-size: 0.875rem; color: var(--gray-500); max-width: 900px; margin-left: auto; margin-right: auto; }
.meta-info span { display: flex; align-items: center; gap: 0.25rem; }
.meta-info svg { width: 16px; height: 16px; }

/* Tables */
.table-responsive { overflow-x: auto; margin: 1rem 0; -webkit-overflow-scrolling: touch; }
.data-table { width: 100%; border-collapse: collapse; font-size: 0.9375rem; }
.data-table th, .data-table td { padding: 0.5rem 1rem; text-align: left; border-bottom: 1px solid var(--gray-200); }
.data-table th { font-weight: 600; color: var(--gray-700); background: var(--gray-50); white-space: nowrap; }
.data-table td { color: var(--gray-600); font-family: var(--font-mono); font-size: 0.875rem; }
.data-table tbody tr:hover { background: var(--gray-50); }
.data-table .highlight { background: var(--primary-bg); }

/* Z-index fixes */
.calc-select, .calc-setting-select, .form-select { position: relative; z-index: 10; }
.calc-select:focus, .calc-setting-select:focus, .form-select:focus { z-index: 20; }

/* Formula */
.formula-box { padding: 1.5rem; margin: 1.5rem 0; background: var(--gray-900); border-radius: var(--radius-lg); overflow-x: auto; }
.formula { font-family: var(--font-mono); font-size: 1.125rem; color: var(--primary-light); text-align: center; white-space: nowrap; }
.formula-variables { margin-top: 1.5rem; padding: 1rem; background: var(--gray-50); border-radius: var(--radius-md); }
.formula-variables dt { font-weight: 600; color: var(--gray-700); }
.formula-variables dd { margin-left: 1.5rem; margin-bottom: 0.5rem; color: var(--gray-600); }

/* Example Box */
.example-box { padding: 1.5rem; margin: 1.5rem 0; background: var(--primary-bg); border-radius: var(--radius-lg); border-left: 4px solid var(--primary); }
.example-box h4 { margin-top: 0; margin-bottom: 1rem; color: var(--primary-dark); }
.example-box .load-example-btn { margin-top: 1rem; padding: 0.5rem 1rem; font-size: 0.875rem; font-weight: 500; color: var(--primary-dark); background: white; border: 1px solid var(--primary); border-radius: var(--radius-md); cursor: pointer; transition: all 0.15s ease; }
.example-box .load-example-btn:hover { background: var(--primary); color: white; }
.example-specs { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: 0.5rem; margin: 1rem 0; }
.example-spec { display: flex; align-items: center; gap: 0.25rem; font-size: 0.875rem; }
.example-spec-label { color: var(--gray-500); }
.example-spec-value { font-weight: 600; color: var(--gray-800); font-family: var(--font-mono); }
.example-result { display: flex; align-items: center; gap: 0.5rem; margin-top: 0.5rem; font-weight: 600; }
.example-result.success { color: var(--success); }
.example-result.warning { color: #b45309; }
.example-result.error { color: var(--error); }

/* Step by Step */
.step-by-step { counter-reset: step; }
.step { position: relative; padding-left: 3rem; padding-bottom: 1.5rem; border-left: 2px solid var(--gray-200); margin-left: 1rem; }
.step:last-child { border-left: none; padding-bottom: 0; }
.step::before { counter-increment: step; content: counter(step); position: absolute; left: -15px; top: 0; width: 28px; height: 28px; display: flex; align-items: center; justify-content: center; font-size: 0.875rem; font-weight: 600; color: white; background: var(--primary); border-radius: 50%; }
.step h4 { margin-top: 0; margin-bottom: 0.5rem; }
.step-formula { font-family: var(--font-mono); font-size: 0.9375rem; padding: 0.5rem 1rem; background: var(--gray-100); border-radius: var(--radius-md); display: inline-block; }

/* FAQ */
.faq-list { display: flex; flex-direction: column; gap: 1rem; }
.faq-item { border: 1px solid var(--gray-200); border-radius: var(--radius-lg); overflow: hidden; }
.faq-question { width: 100%; padding: 1rem 1.5rem; display: flex; align-items: center; justify-content: space-between; gap: 1rem; font-size: 1rem; font-weight: 500; text-align: left; color: var(--gray-800); background: var(--gray-50); border: none; cursor: pointer; transition: all 0.15s ease; }
.faq-question:hover { background: var(--gray-100); }
.faq-question svg { width: 20px; height: 20px; 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 1.5rem 1.5rem; background: white; }
.faq-item.open .faq-answer { display: block; }
.faq-answer p:last-child { margin-bottom: 0; }

/* CTA Box */
.cta-box { padding: 2rem; margin: 2rem 0; background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%); border-radius: var(--radius-xl); text-align: center; }
.cta-box h3 { color: white; margin-top: 0; margin-bottom: 0.5rem; }
.cta-box p { color: rgba(255, 255, 255, 0.9); margin-bottom: 1.5rem; }
.cta-btn { display: inline-flex; align-items: center; gap: 0.5rem; padding: 1rem 2rem; font-size: 1rem; font-weight: 600; color: var(--primary-dark); background: white; border-radius: var(--radius-lg); text-decoration: none; transition: all 0.15s ease; box-shadow: var(--shadow-md); }
.cta-btn:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); text-decoration: none; }

/* Sources */
.sources-list { list-style: none; padding: 0; }
.sources-list li { padding: 0.5rem 0; border-bottom: 1px solid var(--gray-100); font-size: 0.9375rem; }
.sources-list li:last-child { border-bottom: none; }
.sources-list a { display: flex; align-items: center; gap: 0.5rem; }
.sources-list svg { width: 16px; height: 16px; color: var(--gray-400); }

/* Blog */
.blog-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 1.5rem; margin-top: 2rem; }
.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: 1.5rem; }
.blog-card-meta { font-size: 0.8125rem; color: var(--gray-500); margin-bottom: 0.5rem; }
.blog-card h3 { margin-top: 0; margin-bottom: 0.5rem; font-size: 1.125rem; }
.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: 0.9375rem; color: var(--gray-600); margin-bottom: 1rem; }
.blog-card-link { font-size: 0.875rem; font-weight: 500; display: inline-flex; align-items: center; gap: 0.25rem; }
.blog-card-link svg { width: 16px; height: 16px; transition: transform 0.15s ease; }
.blog-card-link:hover svg { transform: translateX(4px); }

/* Article */
.article-header { margin-bottom: 2rem; }
.article-header h1 { margin-bottom: 1rem; }
.breadcrumb { display: flex; align-items: center; gap: 0.5rem; margin-bottom: 1.5rem; font-size: 0.875rem; color: var(--gray-500); }
.breadcrumb a { color: var(--gray-500); }
.breadcrumb a:hover { color: var(--primary-dark); }
.breadcrumb svg { width: 16px; height: 16px; }
.article-meta { display: flex; align-items: center; gap: 1.5rem; font-size: 0.875rem; color: var(--gray-500); }

/* TOC */
.toc { padding: 1.5rem; margin: 1.5rem 0; background: var(--gray-50); border-radius: var(--radius-lg); }
.toc h2 { margin-top: 0; font-size: 1rem; border-bottom: none; }
.toc h2::after { display: none; }
.toc ol { margin: 0; padding-left: 1.5rem; }
.toc li { padding: 0.25rem 0; }
.toc a { color: var(--gray-600); font-size: 0.9375rem; }
.toc a:hover { color: var(--primary-dark); }

/* Related */
.related-articles { margin-top: 3rem; padding-top: 2rem; border-top: 1px solid var(--gray-200); }
.related-articles h2 { margin-top: 0; }

/* Footer */
.footer { background: var(--gray-900); color: var(--gray-400); padding: 3rem 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); }
.footer-brand p { font-size: 0.875rem; line-height: 1.7; }
.footer-nav h4 { color: white; font-size: 0.875rem; 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); transition: color 0.15s ease; }
.footer-nav a:hover { color: white; text-decoration: none; }
.footer-bottom { padding-top: 1.5rem; border-top: 1px solid var(--gray-800); display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 1rem; font-size: 0.8125rem; }
.footer-disclaimer { max-width: 600px; font-size: 0.75rem; color: var(--gray-500); line-height: 1.6; }

/* Utilities */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.text-center { text-align: center; }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-error { color: var(--error); }

/* Callout Boxes */
.callout-box { padding: 1.5rem; margin: 1.5rem auto; border-radius: var(--radius-lg); max-width: 900px; }
.callout-box h3, .callout-box h4 { margin-top: 0; margin-bottom: 1rem; }
.callout-box ul { margin-bottom: 0; padding-left: 1.5rem; }
.callout-box li { margin-bottom: 0.5rem; }
.callout-box li:last-child { margin-bottom: 0; }
.callout-box.primary { background: var(--primary-bg); border-left: 4px solid var(--primary); }
.callout-box.primary h3, .callout-box.primary h4 { color: var(--primary-dark); }
.callout-box.tip { background: var(--gray-50); border-left: 4px solid var(--gray-400); }
.callout-box.tip h4 { color: var(--gray-700); }
.callout-box.success { background: var(--success-bg); border-left: 4px solid var(--success); }
.callout-box.success h4 { color: var(--success); }
.callout-box.warning { background: var(--warning-bg); border-left: 4px solid var(--warning); }
.callout-box.warning h4 { color: #b45309; }
.callout-box.error { background: var(--error-bg); border-left: 4px solid var(--error); }
.callout-box.error h4 { color: var(--error); }

/* Badges */
.badge { display: inline-block; padding: 0.25rem 0.75rem; font-size: 0.75rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.03em; border-radius: var(--radius-full); }
.badge.success { background: var(--success-bg); color: var(--success); }
.badge.warning { background: var(--warning-bg); color: #b45309; }
.badge.error { background: var(--error-bg); color: var(--error); }

/* Enhanced Example Box */
.example-scenario { font-style: italic; color: var(--gray-600); margin-bottom: 1rem; font-size: 0.9375rem; }
.example-calculation { padding: 0.75rem 1rem; background: white; border-radius: var(--radius-md); margin: 1rem 0; font-family: var(--font-mono); font-size: 0.875rem; }
.example-analysis { font-size: 0.9375rem; margin-top: 0.75rem; }
.example-solution { font-size: 0.9375rem; margin-top: 0.5rem; padding: 0.75rem 1rem; background: white; border-radius: var(--radius-md); }

/* Data Table Status Colors */
.data-table .status-excellent td:first-child { border-left: 4px solid var(--success); }
.data-table .status-good td:first-child { border-left: 4px solid var(--success); }
.data-table .status-marginal td:first-child { border-left: 4px solid var(--warning); }
.data-table .status-poor td:first-child { border-left: 4px solid var(--error); }
.data-table .status-critical td:first-child { border-left: 4px solid var(--error); }

/* Form Input Styles (Contact Page) */
.contact-form .form-group { margin-bottom: 1rem; }
.contact-form .form-input { width: 100%; height: 44px; padding: 0 0.875rem; 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; cursor: text; }
.contact-form .form-input:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-bg); }
.contact-form .form-input::placeholder { color: var(--gray-400); }
.contact-form textarea.form-input { height: auto; min-height: 120px; padding: 0.75rem 0.875rem; resize: vertical; }
.contact-form .form-select { width: 100%; height: 44px; padding: 0 2.5rem 0 0.875rem; 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); cursor: pointer; appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 10px center; transition: all 0.15s ease; }
.contact-form .form-select:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-bg); }

/* Date and Time Inputs - Make fully clickable */
input[type="date"],
input[type="time"],
input[type="datetime-local"] {
  cursor: pointer;
  position: relative;
}
input[type="date"]::-webkit-calendar-picker-indicator,
input[type="time"]::-webkit-calendar-picker-indicator,
input[type="datetime-local"]::-webkit-calendar-picker-indicator {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
}

/* General Input Improvements */
input:not([type="checkbox"]):not([type="radio"]),
select,
textarea {
  -webkit-appearance: none;
  -moz-appearance: none;
}

/* Ensure all clickable elements have pointer cursor */
select,
button,
[type="submit"],
[type="button"],
[type="reset"],
.calc-material-option,
.unit-toggle-switch,
.faq-question {
  cursor: pointer;
}

/* ============================================
   ENHANCED RESULTS SECTION STYLES
   ============================================ */

/* Results Sub-Sections */
.results-subsection { margin-top: 1.5rem; padding-top: 1.5rem; border-top: 1px solid var(--gray-200); }
.results-subsection:first-of-type { margin-top: 1rem; padding-top: 0; border-top: none; }
.results-subsection-title { font-size: 0.9375rem; font-weight: 600; color: var(--gray-800); margin-bottom: 1rem; display: flex; align-items: center; gap: 0.5rem; }
.results-subsection-title svg { width: 18px; height: 18px; color: var(--primary); }

/* NEC Compliance Gauge */
.nec-gauge { margin: 1.5rem 0; }
.nec-gauge-bar { position: relative; height: 44px; background: var(--gray-100); border-radius: var(--radius-lg); overflow: visible; display: flex; }
.nec-gauge-segment { height: 100%; display: flex; align-items: center; justify-content: center; font-size: 0.6875rem; font-weight: 600; color: white; transition: all 0.3s ease; position: relative; }
.nec-gauge-segment.good { background: var(--success); flex: 3; border-radius: var(--radius-lg) 0 0 var(--radius-lg); }
.nec-gauge-segment.caution { background: var(--warning); flex: 2; }
.nec-gauge-segment.poor { background: var(--error); flex: 5; border-radius: 0 var(--radius-lg) var(--radius-lg) 0; }
.nec-gauge-marker { position: absolute; top: -8px; width: 4px; height: 60px; background: var(--gray-800); border-radius: 2px; transform: translateX(-50%); z-index: 10; box-shadow: 0 2px 8px rgba(0,0,0,0.3); }
.nec-gauge-marker::after { content: attr(data-value); position: absolute; top: -24px; left: 50%; transform: translateX(-50%); font-size: 0.875rem; font-weight: 700; color: var(--gray-800); white-space: nowrap; background: white; padding: 2px 8px; border-radius: var(--radius-sm); box-shadow: var(--shadow-sm); }
.nec-gauge-labels { display: flex; justify-content: space-between; margin-top: 0.5rem; font-size: 0.6875rem; color: var(--gray-500); }
.nec-gauge-labels span { display: flex; flex-direction: column; align-items: center; gap: 0.125rem; }
.nec-gauge-labels .label-value { font-weight: 600; color: var(--gray-700); }

/* Summary Tables */
.summary-table { width: 100%; border-collapse: collapse; font-size: 0.875rem; }
.summary-table th, .summary-table td { padding: 0.75rem 1rem; text-align: left; border-bottom: 1px solid var(--gray-100); }
.summary-table th { font-size: 0.75rem; font-weight: 600; color: var(--gray-500); text-transform: uppercase; letter-spacing: 0.03em; background: var(--gray-50); }
.summary-table td { color: var(--gray-700); }
.summary-table td:first-child { font-weight: 500; color: var(--gray-800); }
.summary-table .value-cell { font-family: var(--font-mono); font-weight: 600; }
.summary-table .value-cell.success { color: var(--success); }
.summary-table .value-cell.warning { color: var(--warning); }
.summary-table .value-cell.error { color: var(--error); }
.summary-table .reference-cell { font-size: 0.8125rem; color: var(--gray-500); }
.summary-table tbody tr:hover { background: var(--gray-50); }
.summary-table-compact th, .summary-table-compact td { padding: 0.5rem 0.75rem; }

/* Input Summary Grid */
.input-summary-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 0.75rem; }
.input-summary-item { padding: 0.75rem; background: var(--gray-50); border-radius: var(--radius-md); text-align: center; }
.input-summary-label { font-size: 0.6875rem; font-weight: 500; color: var(--gray-500); text-transform: uppercase; letter-spacing: 0.03em; margin-bottom: 0.25rem; }
.input-summary-value { font-size: 1rem; font-weight: 600; font-family: var(--font-mono); color: var(--gray-800); }

/* Tips Grid */
.tips-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1rem; }
@media (max-width: 600px) { .tips-grid { grid-template-columns: 1fr; } }
.tip-card { display: flex; gap: 0.75rem; padding: 1rem; background: var(--gray-50); border-radius: var(--radius-md); border: 1px solid var(--gray-100); }
.tip-icon { width: 36px; height: 36px; border-radius: var(--radius-md); background: var(--primary-bg); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.tip-icon svg { width: 18px; height: 18px; color: var(--primary); }
.tip-content { flex: 1; min-width: 0; }
.tip-title { font-size: 0.875rem; font-weight: 600; color: var(--gray-800); margin-bottom: 0.25rem; }
.tip-description { font-size: 0.8125rem; color: var(--gray-600); line-height: 1.5; }

/* What This Means Section */
.interpretation-box { padding: 1.25rem; background: linear-gradient(135deg, var(--gray-50) 0%, white 100%); border-radius: var(--radius-lg); border: 1px solid var(--gray-200); }
.interpretation-box.success { background: linear-gradient(135deg, var(--success-bg) 0%, white 100%); border-color: rgba(16, 185, 129, 0.2); }
.interpretation-box.warning { background: linear-gradient(135deg, var(--warning-bg) 0%, white 100%); border-color: rgba(245, 158, 11, 0.2); }
.interpretation-box.error { background: linear-gradient(135deg, var(--error-bg) 0%, white 100%); border-color: rgba(239, 68, 68, 0.2); }
.interpretation-title { font-size: 1rem; font-weight: 600; color: var(--gray-800); margin-bottom: 0.75rem; display: flex; align-items: center; gap: 0.5rem; }
.interpretation-title svg { width: 20px; height: 20px; }
.interpretation-box.success .interpretation-title svg { color: var(--success); }
.interpretation-box.warning .interpretation-title svg { color: var(--warning); }
.interpretation-box.error .interpretation-title svg { color: var(--error); }
.interpretation-text { font-size: 0.9375rem; color: var(--gray-700); line-height: 1.6; margin-bottom: 0.75rem; }
.interpretation-text:last-child { margin-bottom: 0; }
.interpretation-action { font-size: 0.875rem; font-weight: 500; color: var(--gray-600); padding-left: 1rem; border-left: 3px solid var(--gray-300); margin-top: 0.75rem; }
.interpretation-box.success .interpretation-action { border-color: var(--success); }
.interpretation-box.warning .interpretation-action { border-color: var(--warning); }
.interpretation-box.error .interpretation-action { border-color: var(--error); }

/* Formula Display */
.formula-display { margin-top: 1rem; padding: 1rem; background: var(--gray-900); border-radius: var(--radius-md); }
.formula-display-title { font-size: 0.6875rem; font-weight: 600; 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); }
.formula-display-breakdown { margin-top: 0.75rem; padding-top: 0.75rem; border-top: 1px solid var(--gray-700); font-size: 0.8125rem; color: var(--gray-400); }

/* Print Button */
.print-btn { display: inline-flex; align-items: center; gap: 0.5rem; padding: 0.625rem 1rem; 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; }

/* Wire Comparison Mini Chart */
.wire-comparison { margin-top: 1rem; }
.wire-comparison-item { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 0.5rem; }
.wire-comparison-item:last-child { margin-bottom: 0; }
.wire-comparison-label { width: 80px; font-size: 0.75rem; font-weight: 500; color: var(--gray-600); flex-shrink: 0; }
.wire-comparison-bar { flex: 1; height: 24px; background: var(--gray-100); border-radius: var(--radius-sm); overflow: hidden; position: relative; }
.wire-comparison-fill { height: 100%; border-radius: var(--radius-sm); transition: width 0.3s ease; display: flex; align-items: center; justify-content: flex-end; padding-right: 0.5rem; }
.wire-comparison-fill span { font-size: 0.6875rem; font-weight: 600; color: white; }
.wire-comparison-fill.current { background: var(--gray-400); }
.wire-comparison-fill.recommended { background: var(--success); }

/* Collapsible Sections */
.collapsible-trigger { display: flex; align-items: center; justify-content: space-between; width: 100%; padding: 0.75rem 0; font-size: 0.875rem; font-weight: 500; color: var(--gray-600); background: none; border: none; cursor: pointer; text-align: left; }
.collapsible-trigger:hover { color: var(--gray-800); }
.collapsible-trigger svg { width: 16px; height: 16px; transition: transform 0.2s ease; }
.collapsible-trigger.open svg { transform: rotate(180deg); }
.collapsible-content { display: none; padding-bottom: 1rem; }
.collapsible-content.open { display: block; }

/* Blog Grid & FAQ consistency */
.blog-grid { max-width: 900px; margin-left: auto; margin-right: auto; }
.faq-list { max-width: 900px; margin-left: auto; margin-right: auto; }

/* ============================================
   ENHANCED CONTENT ELEMENTS
   ============================================ */

/* Related Articles Grid */
.related-articles { margin-top: 2rem; }
.related-articles h3 { margin-bottom: 1rem; }
.related-articles-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1rem; }
.related-article-card { display: flex; flex-direction: column; padding: 1.25rem; background: var(--gray-50); border: 1px solid var(--gray-200); border-radius: var(--radius-lg); transition: all 0.15s ease; }
.related-article-card:hover { border-color: var(--primary); background: var(--primary-bg); transform: translateY(-2px); box-shadow: var(--shadow-md); text-decoration: none; }
.related-article-card .related-label { font-size: 0.75rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; color: var(--primary-dark); margin-bottom: 0.5rem; }
.related-article-card .related-title { font-size: 0.9375rem; font-weight: 600; color: var(--gray-900); margin-bottom: 0.5rem; line-height: 1.4; }
.related-article-card:hover .related-title { color: var(--primary-dark); }
.related-article-card .related-desc { font-size: 0.8125rem; color: var(--gray-500); line-height: 1.5; flex: 1; }

/* Stat / Feature Grid */
.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 1rem; margin: 1.5rem 0; }
.stat-card { background: var(--gray-50); border: 1px solid var(--gray-200); border-radius: var(--radius-lg); padding: 1.25rem; text-align: center; }
.stat-card .stat-value { font-size: 1.75rem; font-weight: 700; color: var(--primary-dark); font-family: var(--font-mono); }
.stat-card .stat-label { font-size: 0.8125rem; color: var(--gray-500); margin-top: 0.25rem; }

/* CSS Bar Charts */
.bar-chart { margin: 1.5rem 0; }
.bar-chart-item { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 0.75rem; }
.bar-chart-item:last-child { margin-bottom: 0; }
.bar-chart-label { width: 100px; font-size: 0.8125rem; font-weight: 500; color: var(--gray-700); flex-shrink: 0; text-align: right; }
.bar-chart-track { flex: 1; height: 28px; background: var(--gray-100); border-radius: var(--radius-sm); overflow: hidden; position: relative; }
.bar-chart-fill { height: 100%; border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: flex-end; padding-right: 0.5rem; transition: width 0.4s ease; min-width: 40px; }
.bar-chart-fill span { font-size: 0.75rem; font-weight: 600; color: white; white-space: nowrap; }
.bar-chart-fill.fill-primary { background: var(--primary); }
.bar-chart-fill.fill-secondary { background: var(--secondary); }
.bar-chart-fill.fill-success { background: var(--success); }
.bar-chart-fill.fill-warning { background: var(--warning); }
.bar-chart-fill.fill-error { background: var(--error); }
.bar-chart-fill.fill-copper { background: #d97706; }
.bar-chart-fill.fill-aluminum { background: #9ca3af; }

/* Interlink Box */
.interlink-box { display: flex; align-items: center; gap: 1rem; padding: 1rem 1.25rem; margin: 1.5rem 0; background: var(--primary-bg); border: 1px solid rgba(6, 182, 212, 0.2); border-radius: var(--radius-lg); transition: all 0.15s ease; }
.interlink-box:hover { border-color: var(--primary); box-shadow: var(--shadow-sm); text-decoration: none; }
.interlink-box .interlink-icon { width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; background: var(--primary); border-radius: var(--radius-md); flex-shrink: 0; }
.interlink-box .interlink-icon svg { width: 20px; height: 20px; color: white; }
.interlink-box .interlink-content { flex: 1; }
.interlink-box .interlink-label { font-size: 0.75rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; color: var(--primary-dark); }
.interlink-box .interlink-title { font-size: 0.9375rem; font-weight: 600; color: var(--gray-900); }
.interlink-box:hover .interlink-title { color: var(--primary-dark); }
.interlink-box .interlink-arrow { color: var(--primary); flex-shrink: 0; transition: transform 0.15s ease; }
.interlink-box:hover .interlink-arrow { transform: translateX(4px); }

/* Feature Cards Grid */
.feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; margin: 1.5rem 0; }
.feature-card { padding: 1.25rem; border: 1px solid var(--gray-200); border-radius: var(--radius-lg); background: white; }
.feature-card .feature-icon { width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; background: var(--primary-bg); border-radius: var(--radius-md); margin-bottom: 0.75rem; }
.feature-card .feature-icon svg { width: 20px; height: 20px; color: var(--primary); }
.feature-card h4 { font-size: 0.9375rem; margin-bottom: 0.5rem; }
.feature-card p { font-size: 0.8125rem; color: var(--gray-500); margin-bottom: 0; line-height: 1.5; }

/* Quick Links Section */
.quick-links { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 0.75rem; margin: 1rem 0; }
.quick-link { display: flex; align-items: center; gap: 0.75rem; padding: 0.75rem 1rem; background: white; border: 1px solid var(--gray-200); border-radius: var(--radius-md); transition: all 0.15s ease; }
.quick-link:hover { border-color: var(--primary); background: var(--primary-bg); text-decoration: none; }
.quick-link svg { width: 18px; height: 18px; color: var(--primary); flex-shrink: 0; }
.quick-link span { font-size: 0.875rem; font-weight: 500; color: var(--gray-700); }
.quick-link:hover span { color: var(--primary-dark); }

/* Comparison Table Enhancement */
.comparison-table { width: 100%; border-collapse: collapse; margin: 1rem 0; }
.comparison-table th, .comparison-table td { padding: 0.75rem 1rem; text-align: left; border-bottom: 1px solid var(--gray-200); }
.comparison-table th { background: var(--gray-800); color: white; font-weight: 600; font-size: 0.875rem; }
.comparison-table th:first-child { border-radius: var(--radius-md) 0 0 0; }
.comparison-table th:last-child { border-radius: 0 var(--radius-md) 0 0; }
.comparison-table td { font-size: 0.875rem; color: var(--gray-600); }
.comparison-table tbody tr:nth-child(even) { background: var(--gray-50); }
.comparison-table tbody tr:hover { background: var(--primary-bg); }
.comparison-table .check { color: var(--success); font-weight: 700; }
.comparison-table .cross { color: var(--error); }

/* Blog Category Tags */
.blog-categories { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 1.5rem; }
.blog-category-tag { padding: 0.375rem 1rem; font-size: 0.8125rem; font-weight: 500; border: 1px solid var(--gray-300); border-radius: var(--radius-full); color: var(--gray-600); background: white; cursor: pointer; transition: all 0.15s ease; }
.blog-category-tag:hover, .blog-category-tag.active { background: var(--primary); color: white; border-color: var(--primary); }

/* Featured Article Card */
.featured-article { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; padding: 1.5rem; background: linear-gradient(135deg, var(--primary-bg), white); border: 1px solid rgba(6, 182, 212, 0.2); border-radius: var(--radius-xl); margin-bottom: 2rem; }
.featured-article-content { display: flex; flex-direction: column; justify-content: center; }
.featured-article-badge { display: inline-block; padding: 0.25rem 0.75rem; font-size: 0.75rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; color: white; background: var(--primary); border-radius: var(--radius-full); margin-bottom: 0.75rem; width: fit-content; }
.featured-article h3 { font-size: 1.375rem; margin-bottom: 0.75rem; }
.featured-article h3 a { color: var(--gray-900); }
.featured-article h3 a:hover { color: var(--primary-dark); text-decoration: none; }
.featured-article p { color: var(--gray-600); margin-bottom: 1rem; }
.featured-article-stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(100px, 1fr)); gap: 1rem; padding: 1.25rem; background: white; border-radius: var(--radius-lg); border: 1px solid var(--gray-200); }
.featured-article-stat { text-align: center; }
.featured-article-stat .stat-num { font-size: 1.25rem; font-weight: 700; color: var(--primary-dark); font-family: var(--font-mono); }
.featured-article-stat .stat-desc { font-size: 0.6875rem; color: var(--gray-500); text-transform: uppercase; letter-spacing: 0.05em; }
@media (max-width: 640px) {
  .featured-article { grid-template-columns: 1fr; }
}

/* Breadcrumb enhancement for blog */
.breadcrumb-nav { display: flex; align-items: center; gap: 0.5rem; font-size: 0.8125rem; color: var(--gray-500); margin-bottom: 1.5rem; flex-wrap: wrap; }
.breadcrumb-nav a { color: var(--gray-500); }
.breadcrumb-nav a:hover { color: var(--primary-dark); }
.breadcrumb-nav .sep { color: var(--gray-300); }

/* "Read More" inline links */
.read-more-inline { display: inline-flex; align-items: center; gap: 0.25rem; font-weight: 500; font-size: 0.875rem; }
.read-more-inline::after { content: ' \2192'; transition: transform 0.15s ease; display: inline-block; }
.read-more-inline:hover::after { transform: translateX(4px); }

/* Voltage drop by distance chart */
.vd-distance-chart { margin: 1.5rem 0; padding: 1.25rem; background: var(--gray-50); border-radius: var(--radius-lg); border: 1px solid var(--gray-200); }
.vd-distance-chart h4 { margin-bottom: 1rem; font-size: 0.9375rem; }
.vd-distance-row { display: flex; align-items: center; gap: 0.5rem; margin-bottom: 0.5rem; font-size: 0.8125rem; }
.vd-distance-row:last-child { margin-bottom: 0; }
.vd-distance-label { width: 60px; text-align: right; font-weight: 500; color: var(--gray-600); flex-shrink: 0; font-family: var(--font-mono); }
.vd-distance-bar { flex: 1; height: 22px; background: var(--gray-200); border-radius: var(--radius-sm); overflow: hidden; }
.vd-distance-fill { height: 100%; border-radius: var(--radius-sm); display: flex; align-items: center; padding-left: 0.5rem; }
.vd-distance-fill span { font-size: 0.6875rem; font-weight: 600; color: white; }
.vd-distance-fill.good { background: var(--success); }
.vd-distance-fill.caution { background: var(--warning); }
.vd-distance-fill.poor { background: var(--error); }
.vd-legend { display: flex; gap: 1rem; margin-top: 0.75rem; font-size: 0.75rem; color: var(--gray-500); }
.vd-legend span { display: flex; align-items: center; gap: 0.25rem; }
.vd-legend .dot { width: 10px; height: 10px; border-radius: var(--radius-full); display: inline-block; }
.vd-legend .dot.good { background: var(--success); }
.vd-legend .dot.caution { background: var(--warning); }
.vd-legend .dot.poor { background: var(--error); }

/* Article TOC (Table of Contents) Enhancement */
.toc-box { padding: 1.25rem; background: var(--gray-50); border: 1px solid var(--gray-200); border-radius: var(--radius-lg); margin-bottom: 1.5rem; }
.toc-box h4 { font-size: 0.875rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--gray-500); margin-bottom: 0.75rem; }
.toc-box ol { padding-left: 1.25rem; margin-bottom: 0; }
.toc-box li { margin-bottom: 0.375rem; font-size: 0.875rem; }
.toc-box a { color: var(--gray-700); }
.toc-box a:hover { color: var(--primary-dark); }

/* Print */
@media print {
  .header, .footer, .calculate-btn, .action-btn, .load-example-btn, .cta-box, .nav-toggle, .print-btn { display: none !important; }
  body { background: white; font-size: 11pt; }
  .calculator-card, .results-card, .visualization-card, .content-section { box-shadow: none; border: 1px solid #ddd; max-width: 100%; }
  .results-section { display: block !important; max-width: 100%; }
  .results-subsection { page-break-inside: avoid; }
  .nec-gauge-bar { print-color-adjust: exact; -webkit-print-color-adjust: exact; }
  .tip-card, .interpretation-box { print-color-adjust: exact; -webkit-print-color-adjust: exact; }
}