/* ============================================
   AI ROI Chart — Global Stylesheet
   Mobile-first responsive, CSS variables
   ============================================ */

/* --- Web Font --- */
@import url('https://cdn.jsdelivr.net/gh/orioncactus/pretendard@v1.3.9/dist/web/variable/pretendardvariable-dynamic-subset.min.css');

/* --- Tokens --- */
:root {
  /* Brand / Chart */
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-positive: #16a34a;
  --color-positive-bg: rgba(22, 163, 74, 0.12);
  --color-negative: #dc2626;
  --color-negative-bg: rgba(220, 38, 38, 0.12);
  --color-neutral: #6b7280;
  --color-axis: #d1d5db;

  /* Surface */
  --color-bg: #f8fafc;
  --color-card: #ffffff;
  --color-card-border: #e5e7eb;
  --color-text: #111827;
  --color-text-muted: #6b7280;
  --color-hero-bg: #eff6ff;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Typography */
  --font-sans: 'Pretendard', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 2rem;
  --text-4xl: 2.5rem;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Shadow */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);

  /* Scenario (sensitivity chart) */
  --color-scenario-low: #f59e0b;
  --color-scenario-base: #2563eb;
  --color-scenario-high: #16a34a;

  /* Layout */
  --max-width: 1200px;
  --header-height: 64px;

  /* Enhanced Design Tokens */
  --color-primary-light: #dbeafe;
  --color-accent: #7c3aed;
  --color-accent-light: #ede9fe;
  --gradient-hero: linear-gradient(135deg, #eff6ff 0%, #f0fdf4 50%, #faf5ff 100%);
  --gradient-card-hover: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
  --shadow-colored: 0 4px 14px -3px rgba(37, 99, 235, 0.15);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.08), 0 8px 10px -6px rgba(0,0,0,0.04);
}

/* --- Dark Mode --- */
@media (prefers-color-scheme: dark) {
  :root {
    --color-primary: #60a5fa;
    --color-primary-hover: #93bbfd;
    --color-positive: #4ade80;
    --color-positive-bg: rgba(74, 222, 128, 0.15);
    --color-negative: #f87171;
    --color-negative-bg: rgba(248, 113, 113, 0.15);
    --color-neutral: #9ca3af;
    --color-axis: #4b5563;

    --color-bg: #0f172a;
    --color-card: #1e293b;
    --color-card-border: #334155;
    --color-text: #f1f5f9;
    --color-text-muted: #94a3b8;
    --color-hero-bg: #1e293b;

    --color-scenario-low: #fbbf24;
    --color-scenario-base: #60a5fa;
    --color-scenario-high: #4ade80;

    --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.4), 0 2px 4px -2px rgba(0,0,0,0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.5), 0 4px 6px -4px rgba(0,0,0,0.3);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.4), 0 8px 10px -6px rgba(0,0,0,0.3);
    --shadow-colored: 0 4px 14px -3px rgba(96, 165, 250, 0.25);

    --gradient-hero: linear-gradient(135deg, #0f172a 0%, #1a2744 50%, #0f172a 100%);
    --gradient-card-hover: linear-gradient(135deg, #60a5fa, #a78bfa);
    --color-primary-light: #1e3a5f;
    --color-accent: #a78bfa;
    --color-accent-light: #2e1065;
  }
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--color-primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

img, svg {
  max-width: 100%;
  height: auto;
}

ul, ol {
  list-style: none;
}

/* --- Layout --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.main {
  flex: 1;
}

/* --- Header --- */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-card);
  border-bottom: 1px solid var(--color-card-border);
  height: var(--header-height);
  backdrop-filter: blur(8px);
}

.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.header-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
}

.header-logo:hover {
  text-decoration: none;
}

.header-logo svg {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.header-nav a {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  font-weight: 500;
  transition: color 0.2s;
}

.header-nav a:hover {
  color: var(--color-text);
  text-decoration: none;
}

.lang-switch {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  background: var(--color-bg);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-full);
  padding: 2px;
  font-size: var(--text-sm);
}

.lang-switch a {
  padding: 4px 12px;
  border-radius: var(--radius-full);
  color: var(--color-text-muted);
  font-weight: 500;
  transition: all 0.2s;
}

.lang-switch a:hover {
  text-decoration: none;
  color: var(--color-text);
}

.lang-switch a.active {
  background: var(--color-primary);
  color: #fff;
}

/* Mobile menu toggle */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
  color: var(--color-text);
}

.menu-toggle svg {
  width: 24px;
  height: 24px;
}

@media (max-width: 768px) {
  .menu-toggle {
    display: block;
  }

  .header-nav {
    display: none;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-card);
    border-bottom: 1px solid var(--color-card-border);
    flex-direction: column;
    padding: var(--space-md);
    gap: var(--space-md);
    box-shadow: var(--shadow-md);
  }

  .header-nav.open {
    display: flex;
  }
}

/* --- Hero --- */
.hero {
  background: var(--color-hero-bg);
  padding: var(--space-3xl) 0;
  text-align: center;
}

.hero h1 {
  font-size: var(--text-3xl);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: var(--space-md);
  color: var(--color-text);
}

.hero p {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 600px;
  margin: 0 auto var(--space-xl);
}

@media (min-width: 768px) {
  .hero {
    padding: var(--space-3xl) 0 var(--space-3xl);
  }
  .hero h1 {
    font-size: var(--text-4xl);
  }
}

/* --- Buttons --- */
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 10px 20px;
  font-size: var(--text-sm);
  font-weight: 600;
  font-family: var(--font-sans);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-md);
  background: var(--color-card);
  color: var(--color-text);
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  line-height: 1.4;
}

.button:hover {
  background: var(--color-bg);
  text-decoration: none;
}

.button-primary {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}

.button-primary:hover {
  background: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
}

.button-lg {
  padding: 14px 28px;
  font-size: var(--text-base);
  border-radius: var(--radius-lg);
}

/* --- Form Elements --- */
.form-group {
  margin-bottom: var(--space-lg);
}

.form-label {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-sm);
}

.form-label .unit {
  font-weight: 400;
  color: var(--color-text-muted);
}

.form-help {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-top: var(--space-xs);
}

.input {
  width: 100%;
  padding: 10px 14px;
  font-size: var(--text-base);
  font-family: var(--font-sans);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-md);
  background: var(--color-card);
  color: var(--color-text);
  transition: border-color 0.2s, box-shadow 0.2s;
}

.input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.input-row {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.input-row .input {
  flex: 0 0 140px;
  text-align: right;
  min-width: 0;
}

.input-row .slider {
  flex: 1;
  min-width: 0;
}

@media (max-width: 480px) {
  .input-row {
    flex-wrap: wrap;
  }
  .input-row .slider {
    flex: 1 1 100%;
    order: 2;
  }
  .input-row .input {
    flex: 1 1 100%;
    order: 1;
    text-align: left;
  }
}

/* Slider */
.slider {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  border-radius: 3px;
  background: var(--color-axis);
  outline: none;
  cursor: pointer;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--color-primary);
  cursor: pointer;
  border: 2px solid #fff;
  box-shadow: var(--shadow-sm);
}

.slider::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--color-primary);
  cursor: pointer;
  border: 2px solid #fff;
  box-shadow: var(--shadow-sm);
}

/* Select */
.select {
  width: 100%;
  padding: 10px 14px;
  font-size: var(--text-base);
  font-family: var(--font-sans);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-md);
  background: var(--color-card);
  color: var(--color-text);
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%236b7280' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 36px;
}

/* --- Cards --- */
.card {
  background: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s, transform 0.2s;
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card-link {
  display: block;
  text-decoration: none;
  color: inherit;
}

.card-link:hover {
  text-decoration: none;
}

.card-link:hover .card {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

/* Calculator card grid */
.calc-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-lg);
  margin: var(--space-2xl) 0;
}

@media (min-width: 768px) {
  .calc-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .calc-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.calc-card-icon {
  width: 48px;
  height: 48px;
  margin-bottom: var(--space-md);
}

.calc-card h3 {
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-sm);
  color: var(--color-text);
}

.calc-card p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-md);
}

.calc-card-chart {
  width: 100%;
  height: 80px;
  margin-top: var(--space-sm);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

/* --- Result KPI --- */
.result-card {
  background: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  box-shadow: var(--shadow-sm);
}

.result-main {
  text-align: center;
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-card-border);
}

.result-main .label {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xs);
}

.result-main .value {
  font-size: var(--text-3xl);
  font-weight: 800;
  line-height: 1.1;
}

.result-main .value.positive {
  color: var(--color-positive);
}

.result-main .value.negative {
  color: var(--color-negative);
}

.result-kpi-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
}

.result-kpi {
  text-align: center;
  padding: var(--space-sm);
}

.result-kpi .label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  font-weight: 500;
  margin-bottom: 2px;
}

.result-kpi .value {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
}

.result-assumptions {
  margin-top: var(--space-lg);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-card-border);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-align: center;
}

/* --- Calculator Layout --- */
.calc-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-xl);
  margin: var(--space-2xl) 0;
}

@media (min-width: 1024px) {
  .calc-layout {
    grid-template-columns: 1fr 380px;
  }
}

.calc-layout .result-card {
  align-self: start;
}

.calc-form {
  background: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  box-shadow: var(--shadow-sm);
}

/* --- Chart Container --- */
.chart-container {
  background: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
  margin: var(--space-xl) 0;
}

.chart-container svg {
  width: 100%;
  height: auto;
}

.chart-area {
  aspect-ratio: 16 / 9;
  width: 100%;
  overflow: visible;
}

.chart-area svg {
  overflow: visible;
}

@media (max-width: 768px) {
  .chart-area {
    aspect-ratio: 4 / 3;
  }
}

.chart-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
  margin-top: var(--space-lg);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-card-border);
  flex-wrap: wrap;
}

.chart-meta {
  text-align: right;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text-muted);
  margin-bottom: var(--space-sm);
}

/* --- Ad Slot --- */
.ad-slot {
  background: var(--color-bg);
  border: 1px dashed var(--color-card-border);
  border-radius: var(--radius-md);
  padding: var(--space-xl);
  text-align: center;
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  margin: var(--space-xl) 0;
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* --- Toast --- */
.toast {
  position: fixed;
  bottom: var(--space-xl);
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: var(--color-text);
  color: var(--color-bg);
  padding: 10px 24px;
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: 500;
  box-shadow: var(--shadow-lg);
  z-index: 1000;
  opacity: 0;
  transition: transform 0.3s ease, opacity 0.3s ease;
  pointer-events: none;
}

.toast.visible {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

/* --- Footer --- */
.footer {
  background: var(--color-card);
  border-top: 1px solid var(--color-card-border);
  padding: var(--space-2xl) 0;
  margin-top: auto;
}

.footer .container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-md);
  text-align: center;
}

.footer-links {
  display: flex;
  gap: var(--space-lg);
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

.footer-copy {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

/* --- Section --- */
.section {
  padding: var(--space-2xl) 0;
}

.section-title {
  font-size: var(--text-2xl);
  font-weight: 700;
  text-align: center;
  margin-bottom: var(--space-sm);
}

.section-subtitle {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  text-align: center;
  margin-bottom: var(--space-2xl);
}

/* --- Utility --- */
.text-center { text-align: center; }
.text-positive { color: var(--color-positive); }
.text-negative { color: var(--color-negative); }
.text-muted { color: var(--color-text-muted); }
.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;
}

/* --- Compare Cards (3-way) --- */
.compare-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-lg);
}

@media (min-width: 768px) {
  .compare-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .compare-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.compare-card {
  background: var(--color-card);
  border: 2px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  text-align: center;
  transition: border-color 0.2s;
}

.compare-card.recommended {
  border-color: var(--color-primary);
  position: relative;
}

.compare-card.recommended::before {
  content: attr(data-badge);
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-primary);
  color: #fff;
  font-size: var(--text-xs);
  font-weight: 700;
  padding: 4px 16px;
  border-radius: var(--radius-full);
}

/* --- Page Title --- */
.page-title {
  padding: var(--space-xl) 0 var(--space-md);
}

.page-title h1 {
  font-size: var(--text-2xl);
  font-weight: 800;
  margin-bottom: var(--space-sm);
}

@media (min-width: 768px) {
  .page-title h1 {
    font-size: var(--text-3xl);
  }
}

.page-title p {
  color: var(--color-text-muted);
  font-size: var(--text-base);
  max-width: 700px;
}

/* --- Related Calculators --- */
.related-section {
  padding: var(--space-2xl) 0;
}

.related-section h2 {
  font-size: var(--text-xl);
  font-weight: 700;
  margin-bottom: var(--space-lg);
}

/* ============================================
   v3 Layout — Sticky Chart + Tabs
   ============================================ */

/* Main 2-column layout: input left, chart right */
.calculator-main {
  display: flex;
  flex-direction: column-reverse;
  gap: var(--space-lg);
  margin: var(--space-xl) 0;
}

@media (min-width: 1024px) {
  .calculator-main {
    display: grid;
    grid-template-columns: minmax(320px, 380px) 1fr;
    flex-direction: unset;
  }
}

/* Input panel (left side on desktop, below on mobile) */
.input-panel {
  background: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  box-shadow: var(--shadow-sm);
}

/* Chart panel (right side on desktop, sticky top on mobile) */
.chart-panel {
  background: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
  position: relative;
}

@media (max-width: 1023px) {
  .chart-panel {
    position: sticky;
    top: var(--header-height);
    z-index: 50;
    max-height: 420px;
    overflow: visible;
  }
  .chart-panel .chart-actions {
    display: none;
  }
}

@media (min-width: 1024px) {
  .chart-panel {
    align-self: start;
    position: sticky;
    top: calc(var(--header-height) + var(--space-md));
  }
}

/* --- Chart Tabs --- */
.chart-tabs {
  display: flex;
  gap: 2px;
  background: var(--color-bg);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-md);
  padding: 2px;
  margin-bottom: var(--space-md);
}

.chart-tab {
  flex: 1;
  padding: 8px 16px;
  font-size: var(--text-sm);
  font-weight: 600;
  font-family: var(--font-sans);
  border: none;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-text-muted);
  cursor: pointer;
  transition: all 0.2s;
  text-align: center;
}

.chart-tab:hover {
  color: var(--color-text);
  background: var(--color-card);
}

.chart-tab.active {
  background: var(--color-card);
  color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}

/* --- KPI Overlay (on chart) --- */
.chart-kpi-overlay {
  position: absolute;
  top: var(--space-lg);
  right: var(--space-lg);
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-radius: var(--radius-md);
  padding: var(--space-sm) var(--space-md);
  z-index: 5;
  text-align: right;
  pointer-events: none;
}

@media (prefers-color-scheme: dark) {
  .chart-kpi-overlay {
    background: rgba(30, 41, 59, 0.85);
  }
}

.chart-kpi-overlay .kpi-main-value {
  font-size: var(--text-xl);
  font-weight: 800;
  line-height: 1.2;
}

.chart-kpi-overlay .kpi-main-label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  font-weight: 500;
}

.chart-kpi-overlay .kpi-sub {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-top: 2px;
}

@media (max-width: 1023px) {
  .chart-kpi-overlay {
    position: static;
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    background: var(--color-bg);
    border: 1px solid var(--color-card-border);
    border-radius: var(--radius-md);
    padding: 6px 12px;
    margin-bottom: var(--space-sm);
    text-align: left;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
  .chart-kpi-overlay .kpi-main-value {
    font-size: var(--text-lg);
    white-space: nowrap;
  }
  .chart-kpi-overlay .kpi-main-label {
    white-space: nowrap;
  }
  .chart-kpi-overlay .kpi-sub {
    margin-top: 0;
    margin-left: auto;
    white-space: nowrap;
  }
}

/* --- Secondary KPIs (below chart panel) --- */
.secondary-kpis {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
  margin: var(--space-lg) 0;
}

@media (min-width: 1024px) {
  .secondary-kpis {
    grid-template-columns: repeat(4, 1fr);
  }
}

.secondary-kpi {
  background: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
  text-align: center;
}

.secondary-kpi .label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  font-weight: 500;
  margin-bottom: 2px;
}

.secondary-kpi .value {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
}

/* Mobile chart actions (visible only on small screens) */
.chart-actions-mobile {
  display: none;
}

@media (max-width: 1023px) {
  .chart-actions-mobile {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-md);
    margin: var(--space-md) 0;
    flex-wrap: wrap;
  }
}

/* --- Assumption Summary --- */
.assumption-summary {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-align: center;
  margin: var(--space-sm) 0 var(--space-xl);
}

/* --- SEO Content Section --- */
.seo-content {
  max-width: 800px;
  margin: var(--space-2xl) auto;
  padding: var(--space-2xl);
  background: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  line-height: 1.8;
}

.seo-content h2 {
  font-size: var(--text-xl);
  font-weight: 700;
  margin-bottom: var(--space-lg);
  letter-spacing: -0.01em;
  color: var(--color-text);
}

.seo-content h3 {
  font-size: var(--text-base);
  font-weight: 700;
  margin: var(--space-xl) 0 var(--space-sm);
  color: var(--color-text);
}

.seo-content p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-md);
}

.seo-content ul {
  margin: var(--space-sm) 0 var(--space-md) var(--space-lg);
  list-style: disc;
}

.seo-content li {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-xs);
  line-height: 1.7;
}

/* ============================================
   Design Enhancement Layer
   ============================================ */

/* --- Keyframe Animations --- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideInLeft {
  from { opacity: 0; transform: translateX(-20px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.92); }
  to { opacity: 1; transform: scale(1); }
}

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

@keyframes pulse-ring {
  0% { box-shadow: 0 0 0 0 rgba(37, 99, 235, 0.3); }
  70% { box-shadow: 0 0 0 8px rgba(37, 99, 235, 0); }
  100% { box-shadow: 0 0 0 0 rgba(37, 99, 235, 0); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}

/* --- Entrance Animations --- */
.page-title { animation: fadeInUp 0.6s var(--transition-base) both; }
.input-panel { animation: slideInLeft 0.5s var(--transition-base) 0.1s both; }
.chart-panel { animation: scaleIn 0.5s var(--transition-base) 0.2s both; }
.secondary-kpis { animation: fadeInUp 0.5s var(--transition-base) 0.3s both; }
.related-section { animation: fadeIn 0.6s var(--transition-base) 0.4s both; }

.hero h1 { animation: fadeInUp 0.7s var(--transition-base) both; }
.hero p { animation: fadeInUp 0.7s var(--transition-base) 0.15s both; }
.hero .button { animation: fadeInUp 0.7s var(--transition-base) 0.3s both; }

/* Stagger cards in grid */
.calc-grid .card-link { animation: fadeInUp 0.5s var(--transition-base) both; }
.calc-grid .card-link:nth-child(1) { animation-delay: 0.05s; }
.calc-grid .card-link:nth-child(2) { animation-delay: 0.1s; }
.calc-grid .card-link:nth-child(3) { animation-delay: 0.15s; }
.calc-grid .card-link:nth-child(4) { animation-delay: 0.2s; }
.calc-grid .card-link:nth-child(5) { animation-delay: 0.25s; }
.calc-grid .card-link:nth-child(6) { animation-delay: 0.3s; }
.calc-grid .card-link:nth-child(7) { animation-delay: 0.35s; }
.calc-grid .card-link:nth-child(8) { animation-delay: 0.4s; }
.calc-grid .card-link:nth-child(9) { animation-delay: 0.45s; }
.calc-grid .card-link:nth-child(10) { animation-delay: 0.5s; }

/* --- Enhanced Header --- */
.header {
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(12px) saturate(180%);
  -webkit-backdrop-filter: blur(12px) saturate(180%);
  transition: box-shadow var(--transition-base);
}

@media (prefers-color-scheme: dark) {
  .header {
    background: rgba(15, 23, 42, 0.82);
  }
}

.header-logo {
  transition: opacity var(--transition-fast);
  letter-spacing: -0.02em;
}

.header-logo:hover {
  opacity: 0.8;
}

/* --- Enhanced Hero --- */
.hero {
  background: var(--gradient-hero);
  position: relative;
  overflow: hidden;
  padding: var(--space-3xl) 0 calc(var(--space-3xl) + 1rem);
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 600px 300px at 20% 50%, rgba(37, 99, 235, 0.06) 0%, transparent 70%),
    radial-gradient(ellipse 500px 250px at 80% 50%, rgba(22, 163, 74, 0.05) 0%, transparent 70%);
  pointer-events: none;
}

.hero h1 {
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-primary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

@media (prefers-color-scheme: dark) {
  .hero h1 {
    background: linear-gradient(135deg, #f1f5f9 0%, #93bbfd 100%);
    -webkit-background-clip: text;
    background-clip: text;
  }
}

.hero p {
  font-size: var(--text-lg);
  line-height: 1.7;
}

/* --- Enhanced Buttons --- */
.button {
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.button::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(rgba(255,255,255,0.12), transparent);
  opacity: 0;
  transition: opacity var(--transition-fast);
  pointer-events: none;
}

.button:hover::after {
  opacity: 1;
}

.button:active {
  transform: scale(0.97);
}

.button-primary {
  box-shadow: 0 2px 8px -2px rgba(37, 99, 235, 0.4);
}

.button-primary:hover {
  box-shadow: 0 4px 16px -2px rgba(37, 99, 235, 0.5);
  transform: translateY(-1px);
}

.button-primary:active {
  transform: translateY(0) scale(0.98);
  box-shadow: 0 1px 4px -1px rgba(37, 99, 235, 0.4);
}

.button-lg {
  font-size: var(--text-base);
  letter-spacing: 0.01em;
}

@media (prefers-color-scheme: dark) {
  .button-primary {
    box-shadow: 0 2px 8px -2px rgba(96, 165, 250, 0.35);
  }
  .button-primary:hover {
    box-shadow: 0 4px 16px -2px rgba(96, 165, 250, 0.45);
  }
}

/* --- Enhanced Form Inputs --- */
.form-group {
  position: relative;
}

.form-label {
  letter-spacing: 0.01em;
  transition: color var(--transition-fast);
}

.input {
  transition: border-color var(--transition-base), box-shadow var(--transition-base), background var(--transition-base);
}

.input:hover {
  border-color: var(--color-neutral);
}

.input:focus {
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12), 0 1px 2px rgba(0,0,0,0.04);
}

@media (prefers-color-scheme: dark) {
  .input:focus {
    box-shadow: 0 0 0 3px rgba(96, 165, 250, 0.2), 0 1px 2px rgba(0,0,0,0.2);
  }
}

/* Enhanced Slider */
.slider {
  height: 6px;
  background: linear-gradient(90deg, var(--color-axis) 0%, var(--color-axis) 100%);
  transition: opacity var(--transition-fast);
}

.slider:hover {
  opacity: 0.9;
}

.slider::-webkit-slider-thumb {
  width: 22px;
  height: 22px;
  border: 2.5px solid #fff;
  box-shadow: 0 1px 4px rgba(0,0,0,0.15), 0 0 0 1px rgba(37, 99, 235, 0.1);
  transition: box-shadow var(--transition-fast), transform var(--transition-fast);
}

.slider::-webkit-slider-thumb:hover {
  transform: scale(1.15);
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3), 0 0 0 2px rgba(37, 99, 235, 0.15);
}

.slider::-webkit-slider-thumb:active {
  transform: scale(1.05);
}

.slider::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border: 2.5px solid #fff;
  box-shadow: 0 1px 4px rgba(0,0,0,0.15), 0 0 0 1px rgba(37, 99, 235, 0.1);
  transition: box-shadow var(--transition-fast), transform var(--transition-fast);
}

.slider::-moz-range-thumb:hover {
  transform: scale(1.15);
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3), 0 0 0 2px rgba(37, 99, 235, 0.15);
}

@media (prefers-color-scheme: dark) {
  .slider::-webkit-slider-thumb {
    border-color: var(--color-card);
    box-shadow: 0 1px 4px rgba(0,0,0,0.4), 0 0 0 1px rgba(96, 165, 250, 0.2);
  }
  .slider::-moz-range-thumb {
    border-color: var(--color-card);
    box-shadow: 0 1px 4px rgba(0,0,0,0.4), 0 0 0 1px rgba(96, 165, 250, 0.2);
  }
}

/* --- Enhanced Cards --- */
.card {
  transition: box-shadow var(--transition-base), transform var(--transition-base), border-color var(--transition-base);
  position: relative;
}

.card-link:hover .card {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
  border-color: var(--color-primary);
}

.card-link:active .card {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* Gradient top accent on hover */
.calc-card {
  position: relative;
  overflow: hidden;
}

.calc-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-card-hover);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-base);
}

.card-link:hover .calc-card::before {
  transform: scaleX(1);
}

.calc-card h3 {
  letter-spacing: -0.01em;
  transition: color var(--transition-fast);
}

.card-link:hover .calc-card h3 {
  color: var(--color-primary);
}

/* Icon float on hover */
.calc-card-icon {
  transition: transform var(--transition-base);
}

.card-link:hover .calc-card-icon {
  transform: scale(1.08) translateY(-2px);
}

/* Mini chart shimmer on hover */
.calc-card-chart {
  position: relative;
  overflow: hidden;
}

.calc-card-chart::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.2) 50%, transparent 100%);
  transform: translateX(-100%);
  transition: none;
}

.card-link:hover .calc-card-chart::after {
  animation: shimmer 1.2s ease-in-out;
}

@media (prefers-color-scheme: dark) {
  .calc-card-chart::after {
    background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.06) 50%, transparent 100%);
  }
}

/* --- Enhanced Input Panel --- */
.input-panel {
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-base);
}

.input-panel:hover {
  box-shadow: var(--shadow-md);
}

/* Subtle separator between form groups */
.input-panel .form-group + .form-group {
  padding-top: var(--space-md);
  border-top: 1px solid rgba(0, 0, 0, 0.04);
  margin-top: var(--space-xs);
}

@media (prefers-color-scheme: dark) {
  .input-panel .form-group + .form-group {
    border-top-color: rgba(255, 255, 255, 0.04);
  }
}

/* --- Enhanced Chart Panel --- */
.chart-panel {
  box-shadow: var(--shadow-md);
  transition: box-shadow var(--transition-base);
  overflow: hidden;
}

@media (min-width: 1024px) {
  .chart-panel:hover {
    box-shadow: var(--shadow-lg);
  }
}

/* --- Enhanced KPI Overlay --- */
.chart-kpi-overlay {
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: var(--radius-lg);
  padding: var(--space-md) var(--space-lg);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
}

@media (prefers-color-scheme: dark) {
  .chart-kpi-overlay {
    background: rgba(30, 41, 59, 0.72);
    border-color: rgba(255, 255, 255, 0.08);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
  }
}

.chart-kpi-overlay .kpi-main-value {
  font-size: var(--text-2xl);
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}

@media (max-width: 1023px) {
  .chart-kpi-overlay {
    background: var(--color-bg);
    border: 1px solid var(--color-card-border);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    box-shadow: var(--shadow-sm);
  }
}

/* --- Enhanced Secondary KPIs --- */
.secondary-kpi {
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.secondary-kpi::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-primary);
  opacity: 0.5;
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

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

.secondary-kpi:hover::before {
  transform: scaleX(1);
}

.secondary-kpi .value {
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}

/* Different accent colors for each KPI */
.secondary-kpi:nth-child(1)::before { background: var(--color-primary); }
.secondary-kpi:nth-child(2)::before { background: var(--color-positive); }
.secondary-kpi:nth-child(3)::before { background: var(--color-accent); }
.secondary-kpi:nth-child(4)::before { background: var(--color-positive); }

/* --- Enhanced Chart Tabs --- */
.chart-tabs {
  border-radius: var(--radius-lg);
  padding: 3px;
  gap: 3px;
}

.chart-tab {
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
  font-size: var(--text-sm);
  padding: 10px 16px;
  position: relative;
}

.chart-tab.active {
  box-shadow: var(--shadow-sm);
  font-weight: 700;
}

.chart-tab:not(.active):hover {
  background: rgba(0,0,0,0.03);
}

@media (prefers-color-scheme: dark) {
  .chart-tab:not(.active):hover {
    background: rgba(255,255,255,0.05);
  }
}

/* --- Enhanced Chart Actions --- */
.chart-actions .button {
  font-size: var(--text-xs);
  padding: 8px 14px;
  border-radius: var(--radius-md);
}

.chart-actions .button svg {
  transition: transform var(--transition-fast);
}

.chart-actions .button:hover svg {
  transform: translateY(-1px);
}

/* --- Enhanced Footer --- */
.footer {
  position: relative;
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 10%;
  right: 10%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-card-border), transparent);
}

.footer-links a {
  transition: color var(--transition-fast);
  position: relative;
}

.footer-links a:hover {
  color: var(--color-primary);
  text-decoration: none;
}

.footer-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100%;
  height: 1px;
  background: var(--color-primary);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--transition-base);
}

.footer-links a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

/* --- Enhanced Page Title --- */
.page-title h1 {
  letter-spacing: -0.02em;
}

.page-title p {
  line-height: 1.7;
}

/* --- Enhanced Related Section --- */
.related-section h2 {
  letter-spacing: -0.01em;
}

.related-section .calc-grid {
  margin: var(--space-lg) 0 0;
}

.related-section .card {
  padding: var(--space-lg);
}

.related-section .card h3 {
  font-size: var(--text-base);
  margin-bottom: var(--space-xs);
}

.related-section .card p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.5;
}

/* --- Enhanced Ad Slot --- */
.ad-slot {
  border-radius: var(--radius-lg);
  transition: border-color var(--transition-base);
}

.ad-slot:hover {
  border-color: var(--color-neutral);
}

/* --- Enhanced Toast --- */
.toast {
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  font-weight: 600;
  letter-spacing: 0.01em;
}

/* --- Enhanced Language Switch --- */
.lang-switch {
  transition: box-shadow var(--transition-fast);
}

.lang-switch:hover {
  box-shadow: var(--shadow-sm);
}

.lang-switch a.active {
  box-shadow: inset 0 1px 2px rgba(0,0,0,0.1);
  transition: all var(--transition-base);
}

/* --- Compare Card Enhancement --- */
.compare-card {
  transition: all var(--transition-base);
}

.compare-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.compare-card.recommended {
  box-shadow: var(--shadow-colored);
}

.compare-card.recommended:hover {
  box-shadow: 0 8px 24px -4px rgba(37, 99, 235, 0.25);
}

/* --- Section Title Enhancement --- */
.section-title {
  letter-spacing: -0.02em;
  font-weight: 800;
}

/* --- Mobile Optimizations --- */
@media (max-width: 768px) {
  /* Better touch targets */
  .slider::-webkit-slider-thumb {
    width: 26px;
    height: 26px;
  }
  .slider::-moz-range-thumb {
    width: 26px;
    height: 26px;
  }

  /* Smoother mobile menu */
  .header-nav {
    transition: none;
    animation: fadeIn 0.2s ease both;
  }

  /* Card grid spacing on mobile */
  .calc-grid {
    gap: var(--space-md);
  }

  /* Compact KPI on mobile */
  .secondary-kpi {
    padding: var(--space-sm) var(--space-md);
  }
}

/* --- Reduced Motion --- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .card-link:hover .card {
    transform: none;
  }
  .secondary-kpi:hover {
    transform: none;
  }
  .button:active {
    transform: none;
  }
  .button-primary:hover {
    transform: none;
  }
}

/* --- Focus Visible (keyboard nav) --- */
.button:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.chart-tab:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: -2px;
}

.card-link:focus-visible .card {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  box-shadow: var(--shadow-md);
}

.input:focus-visible {
  outline: none;
}

.slider:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 4px;
}

/* --- Scrollbar Styling --- */
@supports (scrollbar-width: thin) {
  * {
    scrollbar-width: thin;
    scrollbar-color: var(--color-axis) transparent;
  }
}

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--color-axis);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-neutral);
}

/* --- Selection Color --- */
::selection {
  background: rgba(37, 99, 235, 0.2);
  color: var(--color-text);
}

@media (prefers-color-scheme: dark) {
  ::selection {
    background: rgba(96, 165, 250, 0.3);
  }
}

/* ============================================
   Guide Pages
   ============================================ */

/* Guide Article */
.guide-article { max-width: 800px; margin: 0 auto; padding: var(--space-xl) var(--space-md); }
.guide-header { margin-bottom: var(--space-2xl); }
.guide-category { display: inline-block; font-size: 0.8rem; color: var(--color-primary); font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: var(--space-sm); }
.guide-meta { font-size: 0.85rem; color: var(--color-text-muted); margin-top: var(--space-sm); }
.guide-intro { font-size: 1.1rem; line-height: 1.7; color: var(--color-text); border-left: 3px solid var(--color-primary); padding-left: var(--space-md); margin: var(--space-lg) 0; }
.guide-body h2 { font-size: var(--text-xl); font-weight: 700; margin: var(--space-2xl) 0 var(--space-md); color: var(--color-text); letter-spacing: -0.01em; }
.guide-body h3 { font-size: var(--text-lg); font-weight: 600; margin: var(--space-xl) 0 var(--space-sm); color: var(--color-text); }
.guide-body p { font-size: var(--text-base); color: var(--color-text-muted); margin-bottom: var(--space-md); line-height: 1.8; }
.guide-body ul, .guide-body ol { margin: var(--space-sm) 0 var(--space-md) var(--space-lg); }
.guide-body ul { list-style: disc; }
.guide-body ol { list-style: decimal; }
.guide-body li { font-size: var(--text-base); color: var(--color-text-muted); margin-bottom: var(--space-xs); line-height: 1.7; }
.guide-body a { color: var(--color-primary); text-decoration: underline; }
.guide-body a:hover { color: var(--color-primary-hover); }
.guide-body strong { color: var(--color-text); font-weight: 600; }

/* Guide Index */
.guide-index-header { text-align: center; padding: var(--space-2xl) 0 var(--space-xl); }
.guide-index-header h1 { font-size: var(--text-3xl); font-weight: 800; margin-bottom: var(--space-sm); letter-spacing: -0.02em; }
.guide-index-header p { color: var(--color-text-muted); font-size: var(--text-lg); max-width: 600px; margin: 0 auto; }
.guide-grid { display: grid; grid-template-columns: 1fr; gap: var(--space-lg); margin: var(--space-xl) 0; }
.guide-card { background: var(--color-card); border: 1px solid var(--color-card-border); border-radius: var(--radius-lg); padding: var(--space-lg); box-shadow: var(--shadow-sm); transition: box-shadow var(--transition-base), transform var(--transition-base), border-color var(--transition-base); }
.guide-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-4px); border-color: var(--color-primary); }
.guide-card-category { font-size: 0.75rem; color: var(--color-primary); font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: var(--space-xs); }
.guide-card h3 { font-size: var(--text-lg); font-weight: 700; color: var(--color-text); margin-bottom: var(--space-xs); letter-spacing: -0.01em; transition: color var(--transition-fast); }
.guide-card:hover h3 { color: var(--color-primary); }
.guide-card p { font-size: var(--text-sm); color: var(--color-text-muted); line-height: 1.6; }
.guide-card-meta { font-size: var(--text-xs); color: var(--color-text-muted); margin-top: var(--space-sm); }

@media (min-width: 768px) { .guide-grid { grid-template-columns: repeat(2, 1fr); } }

/* Guide category section */
.guide-category-section { margin: var(--space-2xl) 0 var(--space-lg); }
.guide-category-title { font-size: var(--text-xl); font-weight: 700; color: var(--color-text); margin-bottom: var(--space-sm); letter-spacing: -0.01em; }