* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  body {
    font-family: 'Roboto', sans-serif;
    background-color: #f5f7fa;
    color: #333;
    line-height: 1.6;
  }

  header {
    background-color: #fff;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 15px 20px;
    position: relative;
  }

  header h1 a {
    text-decoration: none;
    color: #333;
    font-size: 24px;
    font-weight: 500;
    transition: color 0.3s;
  }
  
  header h1 a:hover {
    color: #007BFF;
  }

  .nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: relative;
  }
  
.calculator-section {
    max-width: 1200px;
    margin: 20px auto;
    padding: 20px;
}

.calculator {
    background: #fff;
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
    max-width: 500px;
    margin: 0 auto;
}

.calculator h2 {
    text-align: center;
    font-size: 24px;
    margin-bottom: 20px;
    color: #2c3e50;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    font-size: 16px;
    margin-bottom: 5px;
    display: block;
    color: #333;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px;
    font-size: 16px;
    border: 1px solid #ddd;
    border-radius: 4px;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #007BFF;
    box-shadow: 0 0 0 2px rgba(0,123,255,0.25);
}

button {
    background-color: #007BFF;
    color: #fff;
    padding: 12px 15px;
    font-size: 16px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    width: 100%;
    margin-top: 15px;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #0056b3;
}

.result {
    margin-top: 20px;
    font-size: 18px;
    font-weight: 500;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 4px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

footer {
  text-align: center;
  padding: 30px 20px;
  background: #fff;
  box-shadow: 0 -2px 4px rgba(0, 0, 0, 0.1);
  margin-top: 40px;
  font-size: 14px;
  color: #333;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  text-align: left;
  gap: 30px;
}

.footer-section {
  flex: 1;
  min-width: 200px;
}

.footer-section h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 15px;
  color: #2c3e50;
}

.footer-section ul {
  list-style-type: none;
  padding: 0;
}

.footer-section ul li {
  margin-bottom: 10px;
}

.footer-section ul li a {
  text-decoration: none;
  color: #007BFF;
  font-weight: 500;
  transition: color 0.3s;
}

.footer-section ul li a:hover {
  color: #0056b3;
}

.footer-socials {
  display: flex;
  align-items: center;
  gap: 15px;
  margin-top: 10px;
}

.footer-socials a {
  text-decoration: none;
  color: #333;
  font-size: 20px;
  transition: color 0.3s;
}

.footer-socials a:hover {
  color: #007BFF;
}

.footer-bottom {
  margin-top: 30px;
  font-size: 12px;
  color: #777;
}

  .hamburger {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  color: #333;
  padding: 5px;
  z-index: 100;
}

.main-nav {
  display: flex;
  transition: all 0.3s ease-in-out;
}

.main-nav ul {
  list-style: none;
  display: flex;
  gap: 20px;
  margin: 0;
  padding: 0;
}

.main-nav ul li a {
  text-decoration: none;
  color: #007BFF;
  font-weight: 500;
  padding: 5px 10px;
  border-radius: 4px;
  transition: all 0.3s;
}

.main-nav ul li a:hover,
.main-nav ul li a.active {
  color: #0056b3;
  background-color: #f0f4ff;
}

@media (max-width: 768px) {
  .hamburger {
    display: block;
  }
  .main-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: #fff;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-in-out;
  }

  .main-nav.active {
    max-height: 500px;
  }

  .main-nav ul {
    flex-direction: column;
    gap: 0;
    padding: 10px 20px;
    width: 100%;
  }

  .main-nav ul li {
    margin: 5px 0;
  }

  .main-nav ul li a {
    display: block;
    padding: 12px 15px;
  }

  .footer-container {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .footer-section {
    text-align: center;
  }

  .footer-socials {
    justify-content: center;
  }
}