body {
  margin: 0;
  font-family: 'Segoe UI', sans-serif;
  background: #f0f2f5;
}

nav {
  background: #333;
  padding: 10px;
  text-align: center;
}

nav a {
  color: white;
  margin: 0 15px;
  text-decoration: none;
  font-weight: bold;
}

header {
  text-align: center;
  padding: 30px;
  background: #4CAF50;
  color: white;
}

.centered-box {
  max-width: 400px;
  margin: 50px auto;
  background: white;
  padding: 30px;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
  text-align: center;
}

input {
  width: 100%;
  padding: 10px;
  margin: 10px 0;
  font-size: 16px;
}

button {
  padding: 10px 20px;
  background: #4CAF50;
  color: white;
  border: none;
  cursor: pointer;
}

.slider {
  max-width: 800px;
  margin: 30px auto;
  position: relative;
  overflow: hidden;
  border-radius: 10px;
}

.slide {
  display: none;
}

.slide.active {
  display: block;
  animation: fade 1s ease-in-out;
}

.slide img {
  width: 100%;
  height: auto;
  display: block;
}

@keyframes fade {
  from { opacity: 0.4; }
  to { opacity: 1; }
}