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

:root {
  --primary-color: #4f46e5;
  --primary-hover: #4338ca;
  --secondary-color: #06b6d4;
  --bg-color: #f8fafc;
  --card-bg: #ffffff;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --border-color: #e2e8f0;
  --success-color: #10b981;
  --warning-color: #f59e0b;
  --error-color: #ef4444;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
}

/* Navigation Styles */
.navbar {
  background: var(--card-bg);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 5px;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: block;
  padding: 15px 20px;
  color: var(--text-primary);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
  cursor: pointer;
}

.nav-link:hover {
  color: var(--primary-color);
  background: var(--bg-color);
}

/* Dropdown Menu */
.dropdown-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--card-bg);
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  border-radius: 8px;
  min-width: 250px;
  list-style: none;
  padding: 10px 0;
  z-index: 1001;
}

.nav-item:hover .dropdown-menu {
  display: block;
}

.dropdown-item a {
  display: block;
  padding: 10px 20px;
  color: var(--text-primary);
  text-decoration: none;
  transition: background 0.3s;
}

.dropdown-item a:hover {
  background: var(--bg-color);
  color: var(--primary-color);
}

/* Mobile Menu */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  padding: 15px;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 20px;
}

/* Search Box */
.search-container {
  max-width: 600px;
  margin: 40px auto;
}

.search-box {
  width: 100%;
  padding: 20px 30px;
  font-size: 18px;
  border: 2px solid var(--border-color);
  border-radius: 12px;
  outline: none;
  transition: border-color 0.3s;
}

.search-box:focus {
  border-color: var(--primary-color);
}

/* Tool Cards */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
  margin-top: 40px;
}

.tool-card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s, box-shadow 0.3s;
  text-decoration: none;
  color: inherit;
  display: block;
}

.tool-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

.tool-card h3 {
  color: var(--primary-color);
  margin-bottom: 12px;
  font-size: 18px;
}

.tool-card p {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.6;
}

.tool-icon {
  font-size: 32px;
  margin-bottom: 16px;
}

/* Category Section */
.category-section {
  margin: 60px 0;
}

.category-title {
  font-size: 28px;
  margin-bottom: 24px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 12px;
}

.category-icon {
  font-size: 32px;
}

/* Tool Page Styles */
.tool-page {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 40px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.tool-header {
  margin-bottom: 30px;
}

.tool-header h1 {
  font-size: 32px;
  color: var(--primary-color);
  margin-bottom: 10px;
}

.tool-header p {
  color: var(--text-secondary);
  font-size: 16px;
}

.tool-content {
  margin-bottom: 40px;
}

.input-group {
  margin-bottom: 20px;
}

.input-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 600;
  color: var(--text-primary);
}

.input-group textarea,
.input-group input,
.input-group select {
  width: 100%;
  padding: 12px;
  border: 2px solid var(--border-color);
  border-radius: 8px;
  font-size: 14px;
  font-family: 'Courier New', monospace;
  outline: none;
  transition: border-color 0.3s;
}

.input-group textarea:focus,
.input-group input:focus,
.input-group select:focus {
  border-color: var(--primary-color);
}

.input-group textarea {
  min-height: 200px;
  resize: vertical;
}

.btn {
  padding: 12px 24px;
  border: none;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.3s;
}

.btn-primary {
  background: var(--primary-color);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-hover);
}

.btn-secondary {
  background: var(--secondary-color);
  color: white;
}

.btn-secondary:hover {
  background: #0891b2;
}

.btn-group {
  display: flex;
  gap: 12px;
  margin-top: 20px;
}

.output-area {
  margin-top: 30px;
}

.output-area label {
  display: block;
  margin-bottom: 8px;
  font-weight: 600;
  color: var(--text-primary);
}

.output-box {
  background: var(--bg-color);
  border: 2px solid var(--border-color);
  border-radius: 8px;
  padding: 16px;
  min-height: 150px;
  font-family: 'Courier New', monospace;
  font-size: 14px;
  overflow-x: auto;
  white-space: pre-wrap;
  word-wrap: break-word;
}

/* Related Tools */
.related-tools {
  margin-top: 60px;
  padding-top: 40px;
  border-top: 2px solid var(--border-color);
}

.related-tools h3 {
  font-size: 24px;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.related-tools ul {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 12px;
}

.related-tools li a {
  display: block;
  padding: 12px 16px;
  background: var(--bg-color);
  border-radius: 8px;
  color: var(--primary-color);
  text-decoration: none;
  transition: background 0.3s;
}

.related-tools li a:hover {
  background: var(--border-color);
}

/* Footer */
.footer {
  background: var(--card-bg);
  padding: 40px 20px;
  margin-top: 60px;
  text-align: center;
  color: var(--text-secondary);
}

/* Utility Classes */
.hidden {
  display: none;
}

.error-message {
  color: var(--error-color);
  padding: 12px;
  background: #fef2f2;
  border-radius: 8px;
  margin-top: 12px;
}

.success-message {
  color: var(--success-color);
  padding: 12px;
  background: #f0fdf4;
  border-radius: 8px;
  margin-top: 12px;
}

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

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

  .nav-menu.active {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--card-bg);
    padding: 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  }

  .dropdown-menu {
    position: static;
    box-shadow: none;
    padding-left: 20px;
  }

  .tool-page {
    padding: 20px;
  }

  .btn-group {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }

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

/* Copy Button */
.copy-btn {
  position: absolute;
  right: 12px;
  top: 12px;
  padding: 6px 12px;
  font-size: 12px;
  background: var(--primary-color);
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  transition: background 0.3s;
}

.copy-btn:hover {
  background: var(--primary-hover);
}

.output-wrapper {
  position: relative;
}

/* Loading State */
.loading {
  opacity: 0.6;
  pointer-events: none;
  position: relative;
}

.loading::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 24px;
  height: 24px;
  margin: -12px 0 0 -12px;
  border: 3px solid var(--border-color);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

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