/* Reset & base */

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

body,
html {
  height: 100%;
  font-family: 'Roboto', sans-serif;
  background: url('background.jpg') no-repeat center center fixed;
  background-size: cover;
  color: #f0f4f8;
  line-height: 1.6;
}

/* Overlay for better contrast */

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background: rgba(10, 25, 41, 0.75);
  z-index: -1;
}

/* Header */

header {
  background: rgba(15, 35, 60, 0.85);
  padding: 20px 40px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.4);
  position: sticky;
  top: 0;
  z-index: 100;
}

nav {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-weight: 700;
  font-size: 1.8rem;
  color: #00aaff;
  letter-spacing: 2px;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 30px;
}

.nav-links li a {
  color: #d0e6f8;
  font-weight: 600;
  text-decoration: none;
  transition: color 0.3s ease;
  padding: 8px 12px;
  border-radius: 6px;
}

.nav-links li a:hover,
.nav-links li a:focus {
  background: #00aaff;
  color: #0a1929;
  outline: none;
}

/* Buttons */

.btn-primary {
  background: #00aaff;
  color: #0a1929;
  border: none;
  padding: 10px 20px;
  border-radius: 30px;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.3s ease;
}

.btn-primary:hover,
.btn-primary:focus {
  background: #008fcc;
  outline: none;
}

.btn-large {
  font-size: 1.3rem;
  padding: 14px 40px;
  margin-top: 20px;
  display: inline-block;
}

/* Main */

main {
  max-width: 900px;
  margin: 80px auto 60px auto;
  padding: 0 20px;
}

/* Hero Section */

.hero {
  text-align: center;
  padding: 80px 20px 60px 20px;
}

.hero h1 {
  font-size: 3.2rem;
  margin-bottom: 20px;
  font-weight: 700;
  color: #00aaff;
  text-shadow: 0 2px 6px rgba(0, 0, 0, 0.7);
}

.hero p {
  font-size: 1.3rem;
  max-width: 600px;
  margin: 0 auto 30px auto;
  color: #c5d9eb;
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.6);
}

/* Features Section */

.feature {
  background: rgba(0, 170, 255, 0.15);
  border-left: 6px solid #00aaff;
  margin-bottom: 40px;
  padding: 25px 30px;
  border-radius: 8px;
  box-shadow: 0 4px 14px rgba(0, 170, 255, 0.12);
  transition: background 0.3s ease;
}

.feature:hover {
  background: rgba(0, 170, 255, 0.3);
}

.feature h2 {
  font-size: 1.8rem;
  margin-bottom: 10px;
  font-weight: 700;
}

.feature p {
  font-size: 1.1rem;
  color: #d1e6ff;
}

/* Footer */

footer {
  text-align: center;
  padding: 20px 0;
  font-size: 0.9rem;
  opacity: 0.7;
  background: rgba(15, 35, 60, 0.85);
  box-shadow: inset 0 1px 4px rgba(255, 255, 255, 0.1);
  color: #a0b8d7;
}

/* Responsive */

@media (max-width: 768px) {
  nav {
    flex-wrap: wrap;
    gap: 15px;
  }
  .nav-links {
    justify-content: center;
    width: 100%;
  }
  .hero h1 {
    font-size: 2.3rem;
  }
  .hero p {
    font-size: 1rem;
  }
  main {
    margin: 40px auto 40px auto;
  }
}