body {
    margin: 0;
    font-family: Arial, sans-serif;
    scroll-behavior: smooth;
}

header {
    position: fixed;
    width: 100%;
    background: #111;
    color: white;
    z-index: 1000;
}

header .container {
    display: flex;
    justify-content: space-between;
    padding: 15px;
}

nav a {
    color: white;
    margin: 0 10px;
    text-decoration: none;
}

.hero {
    height: 100vh;
    background: linear-gradient(to right, #111, #333);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.btn {
    background: #00aaff;
    padding: 10px 20px;
    color: white;
    text-decoration: none;
}

.section {
    padding: 100px 20px;
}

.dark {
    background: #f4f4f4;
}

.grid {
    display: flex;
    gap: 20px;
}

.card {
    background: white;
    padding: 20px;
    transition: transform 0.3s;
}

.card:hover {
    transform: translateY(-10px);
}

iframe {
    width: 100%;
    height: 300px;
    border: none;
}

footer {
    text-align: center;
    padding: 20px;
    background: #111;
    color: white;
}

/* animation */
.fade-in {
    opacity: 0;
    transform: translateY(40px);
    transition: 1s;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}