body {
  box-sizing: border-box;
  font-family: 'Inter', sans-serif;
  margin: 0;
  padding: 0;
  background: #f7fafc;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  height: 100%;
}

body {
  height: 100%;
}

/* Header */
.header {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 4px 20px rgba(5, 150, 105, 0.15);
}

.logo-section {
  display: flex;
  align-items: center;
  gap: 15px;
}

.logo {
  width: 50px;
  height: 50px;
  border-radius: 12px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.site-name {
  color: #ffffff;
  font-size: 1.1rem;
  font-weight: 700;
  text-decoration: none;
}

/* Desktop navigation */
.nav-link {
  color: #ffffff;
  text-decoration: none;
  transition: all 0.3s ease;
  font-weight: 500;
  display: inline-block;
}

.nav-link:hover {
  color: #e5e7eb;
  transform: scale(1.08);
}

.nav-link.active {
  text-decoration: underline;
}

/* Dropdown */
.dropdown {
  position: relative;
}

.dropdown-toggle {
  background: none;
  border: none;
  color: #ffffff;
  font-weight: 500;
  cursor: pointer;
  transition: color 0.3s ease;
}

.dropdown-toggle:hover {
  color: #e5e7eb;
}

.dropdown-content {
  display: none;
  position: absolute;
  top: 100%;
  right: 0;
  background: #ffffff;
  min-width: 220px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
  border-radius: 12px;
  margin-top: 8px;
  overflow: hidden;
}

.dropdown-content a {
  color: #4a5568;
  padding: 12px 20px;
  text-decoration: none;
  display: block;
  transition: all 0.3s ease;
  font-size: 14px;
}

.dropdown-content a:hover {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  color: #ffffff;
  padding-left: 28px;
}

.dropdown.open .dropdown-content {
  display: block;
}

/* Mobile menu button */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: #ffffff;
  font-size: 24px;
  cursor: pointer;
}

/* Mobile menu */
.mobile-menu {
  display: none;
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  padding: 12px 20px 20px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}

.mobile-menu.open {
  display: block;
}

.mobile-nav-links a {
  display: block;
  padding: 10px 4px;
  color: #ecfdf5;
  text-decoration: none;
  font-weight: 500;
  border-radius: 4px;
}

.mobile-nav-links a:hover {
  background: rgba(16, 185, 129, 0.25);
}

.mobile-nav-links hr {
  border: 0;
  border-top: 1px solid rgba(16, 185, 129, 0.5);
  margin: 8px 0 4px;
}

/* Page header */
.page-header {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  color: white;
  padding: 60px 20px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.page-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1200 120"><path d="M0,0 Q300,60 600,30 T1200,0 L1200,120 L0,120 Z" fill="rgba(255,255,255,0.05)"/></svg>') repeat-x bottom;
  background-size: 1200px 120px;
  opacity: 0.3;
}

.page-header h1 {
  font-size: 48px;
  font-weight: 800;
  margin-bottom: 16px;
  position: relative;
  z-index: 1;
}

.page-header p {
  font-size: 20px;
  opacity: 0.95;
  position: relative;
  z-index: 1;
}

/* Search Box */
.search-container {
  max-width: 700px;
  margin: -30px auto 40px;
  padding: 0 20px;
  position: relative;
  z-index: 10;
}

.search-box {
  width: 100%;
  padding: 18px 24px 18px 56px;
  font-size: 16px;
  border: 3px solid #059669;
  border-radius: 50px;
  background: white;
  box-shadow: 0 10px 40px rgba(5, 150, 105, 0.2);
  transition: all 0.3s ease;
  font-family: 'Inter', sans-serif;
}

.search-box:focus {
  outline: none;
  box-shadow: 0 15px 50px rgba(5, 150, 105, 0.3);
  border-color: #047857;
}

.search-icon {
  position: absolute;
  left: 44px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 24px;
  color: #059669;
}

/* Stats Bar */
.stats-bar {
  background: white;
  padding: 30px;
  border-radius: 16px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  margin-bottom: 40px;
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  gap: 20px;
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-size: 36px;
  font-weight: 800;
  color: #059669;
  display: block;
}

.stat-label {
  font-size: 14px;
  color: #6b7280;
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* Category sections */
.category-section {
  background: white;
  border-radius: 20px;
  padding: 40px;
  margin-bottom: 40px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
  border-left: 6px solid #059669;
  transition: all 0.3s ease;
}

.category-section:hover {
  box-shadow: 0 12px 40px rgba(5, 150, 105, 0.15);
  transform: translateY(-5px);
}

.category-header {
  display: flex;
  align-items: center;
  margin-bottom: 30px;
  gap: 16px;
  cursor: pointer;
  user-select: none;
}

.category-icon {
  font-size: 48px;
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.1));
}

.category-title {
  font-size: 32px;
  font-weight: 800;
  color: #1a202c;
  margin: 0;
}

.category-count {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  color: white;
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 600;
  margin-left: auto;
}

.toggle-btn {
  background: #e2e8f0;
  border: none;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  cursor: pointer;
  transition: all 0.3s ease;
  color: #059669;
  font-weight: bold;
}

.toggle-btn:hover {
  background: #059669;
  color: white;
  transform: scale(1.1);
}

.toggle-btn.collapsed {
  transform: rotate(180deg);
}

.toggle-btn.collapsed:hover {
  transform: rotate(180deg) scale(1.1);
}

/* Calculator cards */
.calculator-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}

.calculator-card {
  background: linear-gradient(135deg, #f6f8fb 0%, #ffffff 100%);
  padding: 20px;
  border-radius: 12px;
  border: 2px solid #e2e8f0;
  transition: all 0.3s ease;
  text-decoration: none;
  color: #2d3748;
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
}

.calculator-card:hover {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  color: white;
  border-color: transparent;
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(5, 150, 105, 0.3);
}

.calculator-icon {
  font-size: 28px;
  flex-shrink: 0;
}

.calculator-name {
  font-weight: 600;
  font-size: 15px;
}

.hidden {
  display: none !important;
}

/* SEO Content */
.seo-content {
  background: white;
  border-radius: 20px;
  padding: 50px;
  margin: 60px 0;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
  line-height: 1.8;
}

.seo-content h2 {
  font-size: 36px;
  font-weight: 800;
  color: #1a202c;
  margin-bottom: 24px;
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.seo-content h3 {
  font-size: 24px;
  font-weight: 700;
  color: #2d3748;
  margin-top: 32px;
  margin-bottom: 16px;
}

.seo-content p {
  color: #4a5568;
  font-size: 16px;
  margin-bottom: 20px;
}

.seo-content a {
  color: #059669;
  text-decoration: none;
  font-weight: 500;
}

.seo-content a:hover {
  text-decoration: underline;
}

/* FAQ section */
.faq-section {
  background: #ffffff;
  border-radius: 20px;
  padding: 40px 30px;
  margin: 0 0 40px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.06);
}

.faq-title {
  font-size: 28px;
  font-weight: 800;
  margin-bottom: 20px;
  color: #1f2933;
}

.faq-item + .faq-item {
  margin-top: 18px;
}

.faq-item h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 6px;
  color: #111827;
}

.faq-item p {
  margin: 0;
  color: #4b5563;
  font-size: 15px;
}

/* Footer */
.footer {
  background: linear-gradient(135deg, #2d3748 0%, #1a202c 100%);
  color: white;
  padding: 60px 0 20px;
  margin-top: 40px;
}

.footer-column h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 20px;
  color: #a0aec0;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.footer-column ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-column ul li {
  margin-bottom: 12px;
}

.footer-column ul li a {
  color: #cbd5e0;
  text-decoration: none;
  transition: all 0.3s ease;
  display: inline-block;
}

.footer-column ul li a:hover {
  color: #667eea;
  transform: translateX(5px);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  margin-top: 40px;
  padding-top: 30px;
  text-align: center;
  color: #a0aec0;
}

/* No Results */
.no-results {
  text-align: center;
  padding: 60px 20px;
  color: #6b7280;
}

.no-results-icon {
  font-size: 80px;
  margin-bottom: 20px;
  opacity: 0.5;
}

.no-results h3 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 12px;
  color: #2d3748;
}

/* Responsive */
@media (max-width: 768px) {
  .desktop-nav {
    display: none !important;
  }

  .mobile-menu-btn {
    display: block;
  }

  .page-header h1 {
    font-size: 32px;
  }

  .page-header p {
    font-size: 16px;
  }

  .category-section {
    padding: 24px;
  }

  .category-title {
    font-size: 24px;
  }

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

  .seo-content {
    padding: 30px 20px;
  }

  .seo-content h2 {
    font-size: 28px;
  }

  .stats-bar {
    padding: 20px;
  }

  .stat-number {
    font-size: 28px;
  }
}