body {
  margin: 0;
  font-family: "Inter", Arial, sans-serif;
  background: #0f172a;
  color: #e2e8f0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

header {
  position: sticky;
  top: 0;
  background: rgba(2, 6, 23, 0.8);
  backdrop-filter: blur(10px);
  padding: 15px 40px;
}

footer {
  text-align: center;
  padding: 20px;
  background: #020617;
  width: 100%;
  box-sizing: border-box;
}

section, .container, .preview {
  flex: none;
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-weight: bold;
  font-size: 18px;
}

.nav-links {
  display: flex;
  gap: 20px;
}

.nav-links a {
  color: #e2e8f0;
  text-decoration: none;
  position: relative;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -5px;
  width: 0;
  height: 2px;
  background: #38bdf8;
  transition: 0.3s;
}

.nav-links a:hover::after,
.nav-links .active::after {
  width: 100%;
}

.hero {
  height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 20px;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 20px;
}

.hero p {
  font-size: 1.2rem;
  margin-bottom: 30px;
  color: #94a3b8;
}

.hero-buttons {
  display: flex;
  justify-content: center;
  gap: 15px;
}

.btn {
  padding: 12px 20px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: bold;
  display: inline-block;
}

.primary {
  background: #38bdf8;
  color: #020617;
}

.secondary {
  border: 1px solid #38bdf8;
  color: #38bdf8;
}

.preview {
  padding: 60px 40px;
  max-width: 1100px;
  margin: auto;
}

.preview h2 {
  margin-bottom: 30px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}

.container {
  padding: 60px 40px;
  max-width: 1000px;
  margin: auto;
}

.card {
  background: #020617;
  padding: 20px;
  border-radius: 12px;
  margin-bottom: 20px;
  transition: 0.3s;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}