* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Arial, sans-serif;
}

body {
  background: #0d1117;
  color: white;
  overflow-x: hidden;
}

/* 🔥 Animated Blue-Green Gradient Background */
#hero {
  position: relative;
  height: 60vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;

  background: linear-gradient(-45deg, #0044ff, #00c853, #0088ff, #00e676);
  background-size: 400% 400%;
  animation: gradientAnimation 12s ease infinite;
}

@keyframes gradientAnimation {
  0% { background-position: 0% 50%; }
  25% { background-position: 50% 100%; }
  50% { background-position: 100% 50%; }
  75% { background-position: 50% 0%; }
  100% { background-position: 0% 50%; }
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 30px;
  background: rgba(0,0,0,0.85);
  position: sticky;
  top: 0;
  z-index: 1000;
}

header h1 {
  font-size: 20px;
}

nav a {
  color: white;
  margin-left: 15px;
  text-decoration: none;
  font-weight: bold;
}

nav a:hover {
  color: #00e676;
}

section {
  padding: 60px 20px;
  text-align: center;
}

#welcome-msg {
  position: absolute;
  top: 50%;
  left: 0;
  transform: translateY(-50%);
  font-size: 28px;
  font-weight: bold;
  white-space: nowrap;
}

.ebook-card {
  background: #1e1e1e;
  padding: 30px;
  margin: 20px auto;
  max-width: 400px;
  border-radius: 12px;
  box-shadow: 0 5px 20px rgba(0,0,0,0.4);
}

.btn {
  display: inline-block;
  padding: 12px 25px;
  background: #00c853;
  color: white;
  text-decoration: none;
  border-radius: 6px;
  margin-top: 15px;
  font-weight: bold;
}

.btn:hover {
  background: #00e676;
}

footer {
  background: black;
  padding: 20px;
  text-align: center;
}

/* 📱 Mobile Responsive */
@media (max-width: 768px) {

  header {
    flex-direction: column;
    text-align: center;
  }

  nav {
    margin-top: 10px;
  }

  nav a {
    display: block;
    margin: 8px 0;
  }

  #welcome-msg {
    font-size: 18px;
  }

  #hero {
    height: 45vh;
  }
}