body {
  margin: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: #f8f9fa;
  color: #333;
}
.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
}
header {
  background-color: #002b45;
  display: flex;
  align-items: center;
  color: white;
  padding: 1rem 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.logo {
  height: 80px;
  margin-right: 20px;
  display: block;
}
nav ul {
  list-style: none;
  display: flex;
  gap: 20px;
  padding: 0;
}
nav a {
  color: white;
  text-decoration: none;
  font-weight: bold;
}
.hero {
  background: linear-gradient(rgba(0,43,69,0.8), rgba(0,43,69,0.8)), url('banner.jpg') center/cover no-repeat;
  color: white;
  text-align: center;
  padding: 100px 20px;
}
.hero h1 {
  font-size: 2.5rem;
}
.hero .btn {
  background-color: #ffc107;
  color: #002b45;
  padding: 10px 20px;
  text-decoration: none;
  font-weight: bold;
  border-radius: 5px;
  margin-top: 20px;
  display: inline-block;
}
section {
  padding: 60px 0;
}
h2 {
  color: #002b45;
  font-size: 2rem;
  margin-bottom: 20px;
}
.gases ul {
  list-style: disc;
  padding-left: 20px;
}
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}
form input, form textarea {
  width: 100%;
  padding: 10px;
  margin-bottom: 10px;
  border: 1px solid #ccc;
  border-radius: 4px;
}
form button {
  background-color: #002b45;
  color: white;
  padding: 10px 20px;
  border: none;
  border-radius: 4px;
  cursor: pointer;
}
footer {
  background-color: #002b45;
  color: white;
  text-align: center;
  padding: 20px 0;
}