:root {
  --primary-color: #2c3e50;
  --secondary-color: #3498db;
  --accent-color: #e67e22;
  --background: #f8f9fa;
  --text-color: #333;
  --border-color: #e5e7eb;
}

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--background);
  color: var(--text-color);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  line-height: 1.6;
}

.header {
  background: var(--primary-color);
  padding: 1rem;
  position: sticky;
  top: 0;
  z-index: 1000;
}

.nav {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  color: white;
  font-size: 1.5rem;
  text-decoration: none;
  font-weight: bold;
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-links a {
  color: white;
  text-decoration: none;
  font-size: 1rem;
  transition: color 0.3s;
}

.nav-links a:hover {
  color: var(--secondary-color);
}

.wrapper {
  display: flex;
  max-width: 1200px;
  margin: 1rem auto;
  padding: 0 15px;
  gap: 20px;
  flex: 1;
}

.calculator-container {
  flex: 2;
  padding: 1rem;
  background: white;
  border-radius: 8px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.sidebar {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.calculator-tool {
  text-align: center;
  padding: 1rem;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: #fff;
}

.calculate-btn {
  background: var(--primary-color);
  color: white;
  padding: 0.5rem 1rem;
  border: none;
  border-radius: 5px;
  font-size: 0.9rem;
  cursor: pointer;
  width: 100%;
  max-width: 200px;
  margin: 1rem auto 0;
  transition: background 0.3s;
}

.calculate-btn:hover {
  background: #1f2a44;
}

.result-card {
  background: var(--accent-color);
  padding: 1rem;
  border-radius: 8px;
  text-align: center;
  margin: 1rem 0;
}

.result-label {
  font-size: 1rem;
  color: white;
  margin-bottom: 0.5rem;
}

.result-card p {
  font-size: 1rem;
  color: white;
  margin: 0.5rem 0;
}

.why-use-section {
  margin-top: 2rem;
}

.why-use-section h2 {
  font-size: 1.2rem;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

.why-use-section ul {
  list-style-type: disc;
  padding-left: 20px;
}

.why-use-section li {
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
}

.content-section {
  margin: 1rem 0;
}

.content-section h2 {
  font-size: 1.2rem;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

.content-section p {
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

.content-section ul {
  list-style-type: disc;
  padding-left: 20px;
}

.content-section li {
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
}

.dog-image img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.dog-image figcaption {
  font-size: 0.8rem;
  color: #666;
  text-align: center;
  margin-top: 0.5rem;
}

.related-links p {
  font-size: 0.9rem;
}

.related-links a {
  color: var(--secondary-color);
  text-decoration: none;
}

.related-links a:hover {
  text-decoration: underline;
}

.footer {
  background: var(--primary-color);
  color: white;
  padding: 1rem;
  text-align: center;
  margin-top: auto;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 0.5rem;
  flex-wrap: wrap;
}

.footer-links a {
  color: white;
  text-decoration: none;
  font-size: 0.9rem;
}

.footer-links a:hover {
  text-decoration: underline;
}

/* Code Styles for Commands */
code {
  background: #e5e7eb;
  padding: 0.2rem 0.4rem;
  border-radius: 3px;
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  color: var(--primary-color);
}

@media (max-width: 768px) {
  .wrapper {
    flex-direction: column;
    padding: 0 10px;
  }
  .calculator-container,
  .sidebar {
    flex: none;
    width: 100%;
  }
  .nav-links {
    display: none;
  }
  .calculate-btn {
    max-width: 100%;
  }
  .result-card p {
    font-size: 0.9rem;
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: 1.2rem;
  }
  .calculator-tool {
    padding: 0.5rem;
  }
  .result-card {
    padding: 0.5rem;
  }
  .why-use-section h2,
  .content-section h2 {
    font-size: 1rem;
  }
  .why-use-section li,
  .content-section li {
    font-size: 0.8rem;
  }
  .dog-image figcaption {
    font-size: 0.7rem;
  }
  .related-links p {
    font-size: 0.8rem;
  }
  code {
    font-size: 0.8rem;
  }
}