/* CalcDrop - Modern AI-Powered Calculator Platform */
:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --primary-light: #e0e7ff;
  --secondary: #10b981;
  --secondary-light: #d1fae5;
  --accent: #f59e0b;
  --accent-light: #fef3c7;
  --danger: #ef4444;
  --bg: #f8fafc;
  --bg-secondary: #f1f5f9;
  --card: #ffffff;
  --text: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --border: #e2e8f0;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --radius: 16px;
  --radius-sm: 8px;
  --radius-lg: 24px;
  --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode */
[data-theme="dark"] {
  --primary: #818cf8;
  --primary-dark: #6366f1;
  --primary-light: #312e81;
  --secondary: #34d399;
  --secondary-light: #064e3b;
  --bg: #0f172a;
  --bg-secondary: #1e293b;
  --card: #1e293b;
  --text: #f1f5f9;
  --text-secondary: #cbd5e1;
  --text-muted: #64748b;
  --border: #334155;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  transition: background 0.3s, color 0.3s;
}

/* ==================== HEADER ==================== */
.header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  padding: 0.75rem 1rem;
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  background: rgba(255, 255, 255, 0.9);
}

[data-theme="dark"] .header {
  background: rgba(30, 41, 59, 0.9);
}

.header-content {
  max-width: 1400px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.25rem;
}

.logo span {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav {
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

.nav a {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  font-size: 0.95rem;
}

.nav a:hover {
  color: var(--primary);
  background: var(--primary-light);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

/* Theme Toggle */
.theme-toggle {
  background: var(--bg-secondary);
  border: none;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  transition: var(--transition);
  color: var(--text);
}

.theme-toggle:hover {
  background: var(--primary-light);
  color: var(--primary);
}

/* ==================== HERO SECTION ==================== */
.hero {
  background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #06b6d4 100%);
  color: white;
  padding: 4rem 1rem 5rem;
  margin: 0;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.5;
}

.hero-content {
  max-width: 900px;
  margin: 0 auto;
  text-align: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
  padding: 0.5rem 1rem;
  border-radius: 50px;
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.3);
}

.hero-badge .pulse {
  width: 8px;
  height: 8px;
  background: #10b981;
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.5); }
}

.hero h1 {
  font-size: 3.5rem;
  font-weight: 800;
  margin-bottom: 1rem;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.hero h1 .gradient-text {
  background: linear-gradient(135deg, #fef08a, #fbbf24);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.25rem;
  opacity: 0.9;
  max-width: 600px;
  margin: 0 auto 2rem;
  line-height: 1.6;
}

/* Trust Badges */
.trust-badges {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-top: 2rem;
  flex-wrap: wrap;
}

.trust-badge {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  opacity: 0.9;
}

.trust-badge svg {
  width: 20px;
  height: 20px;
}

/* ==================== AI SEARCH ==================== */
.ai-search-container {
  max-width: 700px;
  margin: -2rem auto 0;
  padding: 0 1rem;
  position: relative;
  z-index: 10;
}

.ai-search-box {
  background: var(--card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  padding: 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  border: 2px solid transparent;
  transition: var(--transition);
}

.ai-search-box:focus-within {
  border-color: var(--primary);
  box-shadow: var(--shadow-xl), 0 0 0 4px var(--primary-light);
}

.ai-search-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.25rem;
  flex-shrink: 0;
}

.ai-search-input {
  flex: 1;
  border: none;
  background: transparent;
  font-size: 1.1rem;
  padding: 0.75rem;
  color: var(--text);
  outline: none;
}

.ai-search-input::placeholder {
  color: var(--text-muted);
}

.ai-search-btn {
  background: var(--primary);
  color: white;
  border: none;
  padding: 0.875rem 1.5rem;
  border-radius: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.ai-search-btn:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
}

/* AI Search Suggestions */
.ai-suggestions {
  position: absolute;
  top: 100%;
  left: 1rem;
  right: 1rem;
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow-xl);
  margin-top: 0.5rem;
  max-height: 400px;
  overflow-y: auto;
  display: none;
  z-index: 100;
}

.ai-suggestions.show {
  display: block;
  animation: slideDown 0.2s ease;
}

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

.ai-suggestion-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.25rem;
  cursor: pointer;
  transition: var(--transition);
  border-bottom: 1px solid var(--border);
  text-decoration: none;
  color: var(--text);
}

.ai-suggestion-item:last-child {
  border-bottom: none;
}

.ai-suggestion-item:hover {
  background: var(--bg-secondary);
}

.ai-suggestion-icon {
  width: 44px;
  height: 44px;
  background: var(--primary-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  flex-shrink: 0;
}

.ai-suggestion-content h4 {
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.ai-suggestion-content p {
  font-size: 0.875rem;
  color: var(--text-muted);
}

.ai-suggestion-tag {
  margin-left: auto;
  background: var(--secondary-light);
  color: var(--secondary);
  padding: 0.25rem 0.75rem;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 600;
}

/* Quick Examples */
.quick-examples {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  margin-top: 1rem;
  flex-wrap: wrap;
}

.quick-example {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  padding: 0.5rem 1rem;
  border-radius: 50px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: var(--transition);
}

.quick-example:hover {
  background: var(--primary-light);
  color: var(--primary);
  border-color: var(--primary);
}

/* ==================== MAIN CONTAINER ==================== */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 3rem 1rem;
}

/* ==================== POPULAR CALCULATORS ==================== */
.popular-section {
  margin-bottom: 4rem;
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.section-title-icon {
  width: 40px;
  height: 40px;
  background: var(--accent-light);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
}

.view-all-link {
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  transition: var(--transition);
}

.view-all-link:hover {
  gap: 0.5rem;
}

/* Popular Cards Grid */
.popular-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.popular-card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-decoration: none;
  color: var(--text);
  box-shadow: var(--shadow);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  border: 2px solid transparent;
  position: relative;
  overflow: hidden;
}

.popular-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s ease;
}

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

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

.popular-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.popular-card-icon {
  width: 56px;
  height: 56px;
  background: var(--primary-light);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
}

.popular-badge {
  background: linear-gradient(135deg, #f59e0b, #ef4444);
  color: white;
  padding: 0.25rem 0.75rem;
  border-radius: 50px;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.popular-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--text);
}

.popular-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 1rem;
  flex-grow: 1;
}

.popular-card-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.popular-card-meta span {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

/* ==================== CATEGORY SECTIONS ==================== */
.category-section {
  margin-bottom: 4rem;
}

.category-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid var(--border);
}

.category-icon {
  width: 48px;
  height: 48px;
  background: var(--primary-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.category-title {
  font-size: 1.5rem;
  font-weight: 700;
}

.category-count {
  background: var(--bg-secondary);
  padding: 0.25rem 0.75rem;
  border-radius: 50px;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-left: auto;
}

/* Calculator Grid */
.calc-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}

.calc-link {
  background: var(--card);
  border-radius: var(--radius);
  padding: 1.25rem;
  text-decoration: none;
  color: var(--text);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  border: 1px solid var(--border);
}

.calc-link:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
  border-color: var(--primary);
  background: var(--primary-light);
}

.calc-icon {
  width: 44px;
  height: 44px;
  background: var(--bg-secondary);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  flex-shrink: 0;
  transition: var(--transition);
}

.calc-link:hover .calc-icon {
  background: var(--primary);
  transform: scale(1.1);
}

.calc-link:hover .calc-icon::after {
  filter: brightness(0) invert(1);
}

.calc-link-content h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
  color: var(--text);
}

.calc-link-content p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.4;
}

/* ==================== CALCULATOR PAGE ==================== */
.calc-page {
  max-width: 700px;
  margin: 0 auto;
  padding: 2rem 1rem;
}

.calc-card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 2rem;
  margin-bottom: 1.5rem;
}

.calc-page-header {
  margin-bottom: 2rem;
}

.calc-title {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  color: var(--text);
}

.calc-description {
  color: var(--text-secondary);
  font-size: 1.1rem;
}

/* Form Elements */
.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text);
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 0.875rem 1rem;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 1rem;
  transition: var(--transition);
  background: var(--card);
  color: var(--text);
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--primary-light);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.form-hint {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 1rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  width: 100%;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text);
  border: 2px solid var(--border);
}

.btn-secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
}

/* Results */
.result {
  background: linear-gradient(135deg, var(--primary) 0%, #8b5cf6 100%);
  color: white;
  padding: 2rem;
  border-radius: var(--radius);
  margin-top: 2rem;
  display: none;
  position: relative;
  overflow: hidden;
}

.result::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -50%;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
}

.result.show {
  display: block;
  animation: slideIn 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateY(-20px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.result-label {
  font-size: 0.9rem;
  opacity: 0.9;
  margin-bottom: 0.25rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  font-weight: 600;
}

.result-value {
  font-size: 2.5rem;
  font-weight: 800;
  position: relative;
  z-index: 1;
}

.result-details {
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255,255,255,0.2);
  font-size: 0.95rem;
}

.result-row {
  display: flex;
  justify-content: space-between;
  margin-bottom: 0.75rem;
}

.result-row:last-child {
  margin-bottom: 0;
}

/* AI Insight Box */
.ai-insight {
  background: var(--card);
  border: 2px solid var(--secondary);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-top: 1.5rem;
  display: none;
}

.ai-insight.show {
  display: block;
  animation: slideIn 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.ai-insight-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.ai-insight-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--secondary), #06b6d4);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.25rem;
}

.ai-insight-header h4 {
  font-weight: 700;
  color: var(--secondary);
}

.ai-insight-content {
  color: var(--text-secondary);
  line-height: 1.7;
}

.ai-insight-content strong {
  color: var(--text);
}

/* Secondary Results */
.result-secondary {
  background: var(--bg-secondary);
  border: 2px solid var(--border);
  color: var(--text);
  padding: 1.5rem;
  border-radius: var(--radius);
  margin-top: 1rem;
  display: none;
}

.result-secondary.show {
  display: block;
  animation: slideIn 0.3s ease;
}

.result-secondary .result-value {
  color: var(--primary);
  font-size: 1.75rem;
}

/* Action Buttons */
.result-actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.result-action-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: var(--transition);
}

.result-action-btn:hover {
  background: var(--primary-light);
  color: var(--primary);
  border-color: var(--primary);
}

/* ==================== FOOTER ==================== */
.footer {
  background: var(--card);
  border-top: 1px solid var(--border);
  padding: 3rem 1rem;
  margin-top: 4rem;
}

.footer-content {
  max-width: 1400px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
}

.footer-brand p {
  color: var(--text-muted);
  margin-top: 1rem;
  max-width: 300px;
}

.footer-links h4 {
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--text);
}

.footer-links a {
  display: block;
  color: var(--text-muted);
  text-decoration: none;
  margin-bottom: 0.5rem;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--primary);
}

.footer-bottom {
  max-width: 1400px;
  margin: 2rem auto 0;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* ==================== BREADCRUMB ==================== */
.breadcrumb {
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

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

.breadcrumb a:hover {
  text-decoration: underline;
}

.breadcrumb span {
  color: var(--text-muted);
}

/* ==================== RELATED CALCULATORS ==================== */
.related {
  margin-top: 2rem;
}

.related h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 0.75rem;
}

.related-link {
  background: var(--card);
  padding: 1rem;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--text);
  border: 1px solid var(--border);
  transition: var(--transition);
  font-size: 0.95rem;
  font-weight: 500;
  text-align: center;
}

.related-link:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: var(--primary-light);
}

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

.faq-section h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  margin-bottom: 0.75rem;
  overflow: hidden;
}

.faq-question {
  width: 100%;
  padding: 1rem 1.25rem;
  background: var(--card);
  border: none;
  text-align: left;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}

.faq-question:hover {
  background: var(--bg-secondary);
}

.faq-question .icon {
  transition: transform 0.3s ease;
}

.faq-item.open .faq-question .icon {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 1.25rem;
  max-height: 0;
  overflow: hidden;
  transition: all 0.3s ease;
  background: var(--bg-secondary);
}

.faq-item.open .faq-answer {
  padding: 1rem 1.25rem;
  max-height: 500px;
}

.faq-answer p {
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ==================== INFO SECTION ==================== */
.info-section {
  background: var(--card);
  border-radius: var(--radius);
  padding: 2rem;
  margin-top: 2rem;
  border: 1px solid var(--border);
}

.info-section h2 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.info-section h3 {
  font-size: 1.1rem;
  margin: 1.5rem 0 0.75rem;
  color: var(--text);
}

.info-section p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.info-section ul {
  color: var(--text-secondary);
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

.info-section li {
  margin-bottom: 0.5rem;
}

/* ==================== AD SPACE ==================== */
.ad-space {
  background: var(--bg-secondary);
  border: 2px dashed var(--border);
  padding: 2rem;
  text-align: center;
  color: var(--text-muted);
  border-radius: var(--radius);
  margin: 2rem 0;
  font-size: 0.9rem;
}

/* ==================== CALCULATION HISTORY ==================== */
.history-section {
  background: var(--card);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-top: 1.5rem;
  border: 1px solid var(--border);
}

.history-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.history-header h4 {
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.history-clear {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 0.85rem;
  transition: var(--transition);
}

.history-clear:hover {
  color: var(--danger);
}

.history-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
}

.history-item:last-child {
  border-bottom: none;
}

.history-item-result {
  font-weight: 600;
  color: var(--primary);
}

/* ==================== COMPARISON MODE ==================== */
.comparison-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.comparison-card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 1.5rem;
  border: 2px solid var(--border);
}

.comparison-card.active {
  border-color: var(--primary);
}

.comparison-card h4 {
  font-weight: 700;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.comparison-badge {
  width: 24px;
  height: 24px;
  background: var(--primary);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
}

/* ==================== UTILITIES ==================== */
.text-center { text-align: center; }
.text-primary { color: var(--primary); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }
.text-success { color: var(--secondary); }
.text-warning { color: var(--accent); }
.text-danger { color: var(--danger); }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

/* ==================== RESPONSIVE ==================== */
@media (max-width: 1024px) {
  .footer-content {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
}

@media (max-width: 768px) {
  .header-content {
    flex-wrap: wrap;
  }

  .nav {
    display: none;
  }

  .hero {
    padding: 3rem 1rem 4rem;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .hero p {
    font-size: 1rem;
  }

  .trust-badges {
    gap: 1rem;
  }

  .ai-search-box {
    flex-wrap: wrap;
  }

  .ai-search-btn {
    width: 100%;
    margin-top: 0.5rem;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .calc-grid {
    grid-template-columns: 1fr;
  }

  .popular-grid {
    grid-template-columns: 1fr;
  }

  .footer-content {
    grid-template-columns: 1fr;
    gap: 2rem;
    text-align: center;
  }

  .footer-brand p {
    margin: 1rem auto;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
  }

  .comparison-container {
    grid-template-columns: 1fr;
  }

  .result-value {
    font-size: 2rem;
  }
}

/* ==================== ANIMATIONS ==================== */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.9); }
  to { opacity: 1; transform: scale(1); }
}

.animate-fade-in {
  animation: fadeIn 0.3s ease;
}

.animate-scale-in {
  animation: scaleIn 0.3s ease;
}

/* Loading Spinner */
.spinner {
  width: 20px;
  height: 20px;
  border: 2px solid rgba(255,255,255,0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Tooltip */
.tooltip {
  position: relative;
}

.tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  background: var(--text);
  color: var(--bg);
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  font-size: 0.85rem;
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}

.tooltip:hover::after {
  opacity: 1;
  visibility: visible;
}

/* Print Styles */
@media print {
  .header, .footer, .ad-space, .result-actions, .ai-search-container {
    display: none !important;
  }

  body {
    background: white;
    color: black;
  }

  .calc-card, .result, .result-secondary {
    box-shadow: none;
    border: 1px solid #ddd;
  }

  .result {
    background: #f5f5f5 !important;
    color: black !important;
  }
}

/* Range Slider */
input[type="range"] {
  -webkit-appearance: none;
  width: 100%;
  height: 8px;
  background: var(--border);
  border-radius: 4px;
  outline: none;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 24px;
  height: 24px;
  background: var(--primary);
  border-radius: 50%;
  cursor: pointer;
  box-shadow: var(--shadow);
}

.range-value {
  text-align: center;
  font-weight: 700;
  color: var(--primary);
  margin-top: 0.5rem;
  font-size: 1.25rem;
}

/* Tabs */
.tabs {
  display: flex;
  border-bottom: 2px solid var(--border);
  margin-bottom: 1.5rem;
  gap: 0.25rem;
}

.tab {
  padding: 0.875rem 1.5rem;
  background: none;
  border: none;
  cursor: pointer;
  font-weight: 600;
  color: var(--text-muted);
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: var(--transition);
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
}

.tab:hover {
  color: var(--primary);
  background: var(--primary-light);
}

.tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
  background: var(--primary-light);
}

/* Table */
.result-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}

.result-table th,
.result-table td {
  padding: 0.875rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.result-table th {
  font-weight: 600;
  background: var(--bg-secondary);
  color: var(--text);
}

.result-table tr:hover {
  background: var(--bg-secondary);
}

/* Toggle Switch */
.toggle-group {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.toggle {
  position: relative;
  width: 52px;
  height: 28px;
}

.toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--border);
  border-radius: 28px;
  transition: 0.3s;
}

.toggle-slider:before {
  position: absolute;
  content: "";
  height: 22px;
  width: 22px;
  left: 3px;
  bottom: 3px;
  background: white;
  border-radius: 50%;
  transition: 0.3s;
  box-shadow: var(--shadow-sm);
}

.toggle input:checked + .toggle-slider {
  background: var(--primary);
}

.toggle input:checked + .toggle-slider:before {
  transform: translateX(24px);
}

/* Chart placeholder */
.chart-container {
  height: 250px;
  background: var(--bg-secondary);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 1rem;
  border: 1px solid var(--border);
}

/* Mobile Menu */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text);
}

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

/* ==================== PWA INSTALL BANNER ==================== */
.install-banner {
  position: fixed;
  bottom: -120px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.15);
  z-index: 9999;
  transition: bottom 0.4s ease;
  max-width: 500px;
  width: calc(100% - 2rem);
  display: none;
}

.install-banner.show {
  display: block;
  bottom: 1.5rem;
}

.install-banner-content {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.5rem;
}

.install-banner-icon {
  font-size: 2rem;
  flex-shrink: 0;
}

.install-banner-text {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.install-banner-text strong {
  font-weight: 700;
  color: var(--text);
}

.install-banner-text span {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.install-banner .btn {
  flex-shrink: 0;
  padding: 0.625rem 1.25rem;
}

.install-banner-close {
  background: none;
  border: none;
  font-size: 1.25rem;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.5rem;
  line-height: 1;
  transition: var(--transition);
}

.install-banner-close:hover {
  color: var(--text);
}

@media (max-width: 480px) {
  .install-banner-content {
    flex-wrap: wrap;
    gap: 0.75rem;
  }

  .install-banner .btn {
    width: 100%;
    order: 3;
  }

  .install-banner-close {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
  }

  .install-banner {
    position: relative;
    padding-top: 0.5rem;
  }
}

/* ==================== ACTION BUTTONS ==================== */
.action-buttons {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.5rem;
  flex-wrap: wrap;
  display: none;
}

.action-buttons.show {
  display: flex;
}

.action-buttons .btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex: 1;
  min-width: 100px;
  justify-content: center;
}

/* ==================== HISTORY SECTION IMPROVED ==================== */
.history-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.btn-clear {
  margin-left: auto;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.85rem;
  cursor: pointer;
  transition: var(--transition);
}

.btn-clear:hover {
  color: var(--danger);
}

.history-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.history-item {
  display: flex;
  flex-direction: column;
  padding: 0.875rem;
  background: var(--bg-secondary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
}

.history-item:hover {
  background: var(--primary-light);
}

.history-item-main {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.25rem;
}

.history-service {
  font-weight: 600;
  color: var(--primary);
}

.history-amount {
  font-weight: 700;
}

.history-item-details {
  display: flex;
  gap: 1rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ==================== AI INSIGHTS BOX ==================== */
.ai-insights {
  background: linear-gradient(135deg, var(--primary-light), #dbeafe);
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-top: 1.5rem;
  display: none;
}

[data-theme="dark"] .ai-insights {
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.15), rgba(59, 130, 246, 0.1));
}

.ai-insights.show {
  display: block;
  animation: slideIn 0.3s ease;
}

.ai-insights-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 1rem;
  font-size: 1.1rem;
}

.ai-icon {
  font-size: 1.25rem;
}

.ai-insights-content {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.insight-item {
  display: flex;
  gap: 0.875rem;
  padding: 1rem;
  background: var(--card);
  border-radius: var(--radius-sm);
  border-left: 4px solid var(--border);
}

.insight-item.insight-success {
  border-left-color: var(--secondary);
}

.insight-item.insight-warning {
  border-left-color: var(--accent);
}

.insight-item.insight-info {
  border-left-color: var(--primary);
}

.insight-item.insight-tip {
  border-left-color: #8b5cf6;
}

.insight-icon {
  font-size: 1.25rem;
  flex-shrink: 0;
}

.insight-content {
  flex: 1;
}

.insight-title {
  font-weight: 700;
  color: var(--text);
  margin-bottom: 0.25rem;
}

.insight-text {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ==================== FAQ IMPROVEMENTS ==================== */
.faq-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 1.25rem;
}

.faq-icon {
  font-size: 1.25rem;
  font-weight: 400;
  color: var(--primary);
  transition: transform 0.3s ease;
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}